Risk Assessment at Hazardous Waste Sites 9780841207479, 9780841209893, 0-8412-0747-X

Table of contents :
Title Page......Page 1
Half Title Page......Page 3
Copyright......Page 4
ACS Symposium Series......Page 5
FOREWORD......Page 6
PdftkEmptyString......Page 0
PREFACE......Page 7
Legislative Background of Risk Assessment Under Superfund......Page 9
Description of Key Superfund Provisions......Page 10
Application of the NCP to Private Clean-Up......Page 12
Risk Assessment and Remedy Selection under the Proposed NCP......Page 13
Conclusion......Page 15
Literature Cited......Page 16
2 Case Studies of Hazardous Waste Problems in Louisiana......Page 17
The inherent complexity of such a regulatory program......Page 18
What is a hazardous waste -- and how do we test for it?......Page 19
How big should the 'universe' of hazardous wastes be?......Page 21
Setting regulatory standards and criteria......Page 22
Some mistakes of the past: "abandoned" sites......Page 24
Degree of hazard and level of control......Page 27
3 Determining the Impacts on Human Health Attributable to Hazardous Waste Sites......Page 29
Woburn, Massachusetts - An Example of Descriptive and Case-Control Studies......Page 36
Triana, Alabama - An Example of a Cross-sectional Study......Page 37
Bucks and Montgomery County, Pennsylvania - An Example of a Potential Cohort Study......Page 38
Literature Cited......Page 39
4 Analysis and Risk Assessment: Key to Effective Handling of Hazardous Waste Sites......Page 41
5 An Industry's Guidelines for Risk Assessment......Page 53
Shell Risk Assessment Procedure......Page 54
Hazard Identification......Page 55
Risk Evaluation......Page 56
Risk Response......Page 58
California Site Study......Page 59
Summary......Page 60
Literature Cited......Page 61
6 Methodology for Assessing Uncontrolled Site Problems at the County Level......Page 62
Rationale And Approach......Page 63
Site Identification......Page 64
Geologic Analysis......Page 65
Refinement of Site Information......Page 75
Site Prioritization......Page 76
Acknowledgments......Page 77
Literature Cited......Page 78
7 Monitoring to Support Risk Assessments at Hazardous Waste Sites......Page 79
Relating Monitoring Data to Risks......Page 82
The General Approach to Sampling and Analysis......Page 83
Improved Analytical Methods......Page 87
Monitoring in Animals and Plants......Page 90
Providing More Meaningful Monitoring Data for Health Assessments......Page 96
Literature Cited......Page 97
8 Currently Available Geophysical Methods for Use in Hazardous Waste Site Investigations......Page 98
Field Problems......Page 99
Available Geophysical Methodology......Page 100
Seismic Refraction......Page 114
Risk Assessment in Hazardous Waste Site Investigations......Page 116
Summary......Page 118
Literature Cited......Page 119
9 Incorporating Risk Assessment into the Resource Conservation and Recovery Act Regulatory Process......Page 121
E......Page 128
M......Page 129
T......Page 130
W......Page 131

Citation preview

Risk Assessment at Hazardous Waste Sites

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

Risk Assessment at Hazardous Waste Sites F. A. Long, EDITOR Cornell University

Glenn E. Schweitzer, EDITOR U.S.

Based on a symposium sponsored by the A C S Committee on Environmental Improvement at the 183rd Meeting of the American Chemical Society, Las Vegas, Nevada, March-April 1982.

204

ACS SYMPOSIUM SERIES

AMERICAN

CHEMICAL

W A S H I N G T O N , D. C.

SOCIETY 1982

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

Library of Congress Cataloging in Publication Data Risk assessment at hazardous waste sites. (ACS symposium series, ISSN 0097-6156; 204) Includes index. 1. Hazardous waste facilities—Congresses —Congresses. I. Long, Franklin Α., 1910. II. Schweitzer, Glenn E., 1930. III. American Chemical Society. Committee on Environmental Improvement. IV. Series. TD811.5.R57 1982 ISBN 0-8412-0747-X

363.7'28 82-16376 AACR2 ACSMC8 204 1-128 1982

Copyright © 1982 American Chemical Society All Rights Reserved. The appearance of the code at the bottom of the first page of each article in this volume indicates the copyright owner's consent that reprographic copies of the article may be made for personal or internal use or for the personal or internal use of specific clients. This consent is given on the condition, however, that the copier pay the stated per copy fee through the Copyright Clearance Center, Inc. for copying beyond that permitted by Sections 107 or 108 of the U.S. Copyright Law. This consent does not extend to copying or transmission by any means—graphic or electronic—for any other purpose, such as for general distribution, for advertising or promotional purposes, for creating new collective work, for resale, or for information storage and retrieval systems. The copying fee for each chapter is indicated in the code at the bottom of the first page of the chapter. The citation of trade names and/or names of manufacturers in this publication is not to be construed as an endorsement or as approval by ACS of the commercial products or services referenced herein; nor should the mere reference herein to any drawing, specification, chemical process, or other data be regarded as a license or as a conveyance of any right or permission, to the holder, reader, or any other person or corporation, to manufacture, repro­ duce, use, or sell any patented invention or copyrighted work that may in any way be related thereto. PRINTED I N T H E UNITED STATES O F AMERICA

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

ACS Symposium Series M. Joa

Advisory Board David L. Allara

Marvin Margoshes

Robert Baker

Robert Ory

Donald D. Dollberg

Leon Petrakis

Robert E. Feeney

Theodore Provder

Brian M . Harney

Charles N . Satterfield

W. Jeffrey Howe

Dennis Schuetzle

James D. Idol, Jr.

Davis L. Temple, Jr.

Herbert D. Kaesz

Gunter Zweig

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

FOREWORD The ACS SYMPOSIUM SERIES was founded in 1974 to provide

a medium for publishing symposia quickly in book form. The format of the Series parallels that of the continuing ADVANCES IN CHEMISTRY SERIES except that in order to save time the papers are not typeset but are reproduced as they are submitted by the authors in camera-ready form. Papers are reviewed under the supervision of the Editors with the assistance of the Series Advisory Board and are selected to maintain the integrity of the symposia; however, verbatim reproductions of previously published papers are not accepted. Both reviews and reports of research are acceptable since symposia may embrace both types of presentation.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

PREFACE (CHEMICAL W A S T E S resulting from the activities of U.S. industry and other groups have been dumped into waste sites around the country for many years. Typically the wastes are put into steel drums, not labeled, carried to an authorized dump site, and placed into a pit, which when filled is usually covered with earth. In some waste sites thefilledcontainers are deposited on the surface. Bulk chemicals have been dumped in a few. Wastes other than chemicals are often deposited at the same sites, and illegal dumping has occasionall occurred ther undoubtedl identified sites. Public concern over possible health and environmental impacts of chemical waste sites rose dramatically during the Love Canal episode and has continued to rise. Part of the reason for this concern is the growing awareness of the size and ubiquity of the problem of potentially hazardous waste sites. Another reason is increasing knowledge about the hazards that can arise from waste materials that once were viewed as virtually inert; a good example is PCBs (polychlorinated biphenyls). The extent of danger from older waste sites is particularly uncertain, partly because of the broadening list of potential hazards, and partly because of ignorance about the materials in most of the older sites. The current situation in the United States is that there appear to be many thousands of older dump sites that contain chemical wastes. Probably many, perhaps most, of these sites contain worrisome amounts of hazardous materials. From the start, the Environmental Protection Agency (EPA) has been inescapably involved in this problem through the Resource Conservation and Recovery Act and earlier legislation, but since 1979 it became evident that EPA's normal resources were quite inadequate to deal with the overall problem in a timely way. Therefore in late 1980 the Comprehensive Environmental Compensation and Liability Act of 1980 (the Superfund Act) was passed. The Act revises a more limited National Contingency Plan to permit response to hazardous substances and to provide extra funds for EPA to tackle the problem. A key difficulty in arriving at a rational approach to this many-faceted problem is establishing priorities, i.e., ranking waste sites in terms of potential hazards. This ranking presupposes a reasonably objective set of procedures to assess the risk offered by the sites, presuming that the most risky sites will be thefirstto be cleaned up (or rendered harmless). The question of risk is obviously a complex one, involving both health and

ix In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

environmental aspects, with the potential hazard depending on both the chemicals present and the ways hazardous chemicals might escape and impinge on people and the environment. In March 1982 the American Chemical Society sponsored a sympo­ sium on risk assessments of hazardous chemical waste sites, and the chapters of this volume are the final versions of the papers that were presented and discussed at this symposium. Thefirstchapters present the problem: the history of the development of Superfund legislation and the arguments about the most appropriate approaches to risk assessments, specific cases of hazardous waste problems in Louisiana, the problems of Love Canal and their bearing on risk assessment, and the impacts on human health that can result from hazardous waste sites. The next broad topic of the symposium was the central problem of methodology of risk assess­ ment. The practical problems that confront the field teams who examine specific chemical waste site how to have reasonable assurance of the reliability of the results of moni­ toring. A final chapter considers a problem of central importance to the Superfund effort: how to incorporate risk assessment into the regulatory process. The process of risk assessment for hazardous waste sites is still under development, and so necessarily is the development of regulations that build on risk assessment, but the commitment to utilize risk assessment appears firm. The overall conclusion from the chapters of this book is heartening. The seriousness of the problem is clearly recognized, as is the need for risk assessment. Techniques and methodologies for assessment are fairly well in hand, although improvements in their application will surely occur. The social and political need for risk assessment is clearly recognized, and the incorporation of risk assessment into the regulatory process is well under way. The problems from hazardous chemical wastes are far from solved, but on the evidence of the contributions of this book, they are being attacked with intelligence and vigor. FRANKLIN A. LONG

Cornell University Ithaca, New York August 3, 1982

χ

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

1 Risk Assessment Under the Revised National Contingency Plan of Superfund EDMUND B. FROST Kirkland & Ellis, Washington, DC 20006

The 1980 Congressional revision f th N a t i o n a l Contingency P l a n is effectively a compromise between s h a r p l y differing positions. I t calls f o r priority s e t t i n g t o i d e n t i f y the most hazardous sites, and this in t u r n r e q u i r e s explicit assessment o f the risks from the sites. Hence risk assessment criteria must be e s t a b l i s h e d so t h a t there can be developed a n a t i o n a l priority list of the hazardous sites t h a t r e q u i r e remedial a c t i o n . EPA has adopted the M i t r e Model f o r assess i n g the risks and r a n k i n g waste sites. There i s some criticism o f this model, and there are a number o f as y e t unanswered questions about its application. Formal c o s t / b e n e f i t a n a l y s i s will not be used, and risk assessment will be on a case-by-case b a s i s . EPA will thus be developing its knowledge base and procedures as it c a r r i e s out the program. L e g i s l a t i v e Background o f R i s k Assessment

Under S u p e r f u n d

The p u b l i c a n d l e g i s l a t i v e d e b a t e w h i c h l e d up t o t h e E n a c t ment o f t h e C o m p r e h e n s i v e E n v i r o n m e n t a l R e s p o n s e , C o m p e n s a t i o n , and L i a b i l i t y A c t o f 1980 ("Superfund") f o c u s e d e x t e n s i v e l y o n a s s e s s i n g t h e r i s k s f r o m o l d h a z a r d o u s w a s t e dump s i t e s . Indeed, much o f t h e c o n t r o v e r s y a n d d i f f i c u l t y i n e n a c t i n g t h e b i l l was a r e s u l t o f g r e a t l y d i f f e r i n g p e r c e p t i o n s about the r i s k s posed by o l d dump s i t e s a n d e x p o s u r e t o m i n i m a l l e v e l s o f h a z a r d o u s w a s t e . Those who t o o k a f e a r f u l v i e w o f t h e r i s k s t h o u g h t t h a t t h e c l e a n u p p r o g r a m s h o u l d e l i m i n a t e a l l r i s k . On t h i s p r e m i s e t h e y e s t i m a t e d 30,000 t o 50,000 o l d s i t e s r e q u i r i n g a c t i o n a n d c a l l e d f o r a massive c l e a n u p program. Those who t o o k a c a l m e r v i e w o f t h e r i s k s saw a s e r i o u s b u t manageable p r o b l e m a n d w a n t e d a r e a l i s t i c assessment o f t h e r i s k s i n o r d e r t o determine t h e r e q u i r e d e x t e n t o f c l e a n u p (_1) .

0097-615 6/82/0204-0001 $06.00/0 © 1982 American Chemical Society

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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S. 1480, t h e o r i g i n a l B i l l r e p o r t e d by t h e S e n a t e E n v i r o n ment and P u b l i c Works C o m m i t t e e (_2) was a z e r o - r e l e a s e , z e r o - r i s k bill. I t c o n t e m p l a t e d c l e a n - u p o f s p i l l s and o l d dump s i t e s down to a no-detectable-presence, zero-risk, level. No a l l o w a n c e was made f o r r i s k a n a l y s i s , c o m p a r a t i v e r i s k a n a l y s i s , o r b a l a n c e d d e c i s i o n - m a k i n g where r e s p o n s e a c t i o n and i t s c o s t w o u l d b e a r a reasonable r e l a t i o n s h i p to the r i s k . I n s t e a d , c o s t f a c t o r s were p u t a s i d e i n f a v o r o f a l i a b i l i t y scheme t o t a p deep c o r p o r a t e p o c k e t s f o r whatever expense would a r i s e . H. R. 7020, (3) t h e House b i l l , was d i f f e r e n t f r o m S. 1480. I t p r o v i d e d f o r p r i o r i t i z a t i o n o f c l e a n - u p a c t i v i t i e s , and i t p r o v i d e d f o r r i s k a n a l y s i s and c o s t - e f f e c t i v e c l e a n - u p . By O c t o b e r , 1980, S u p e r f u n d had bogged down i n t h e S e n a t e o v e r t h e e x t e n t o f c l e a n - u p i s s u e s and l i a b i l i t y i s s u e s . The W h i t e House a t t e m p t e d t o g e t t h e l e g i s l a t i o n m o v i n g a g a i n by h o l d i n g a s e r i e s of meeting the J u s t i c e Department Senate S t a f f . E x t e n t o f c l e a n - u p was a m a j o r s u b j e c t o f t h e s e discussions. I t emerged i n t h e W h i t e House d i s c u s s i o n s t h a t EPA was n o t r e a l l y i n t e r e s t e d i n z e r o - r i s k clean-up. EPA j u s t w a n t e d t o p r e s e r v e i t s d i s c r e t i o n r e g a r d i n g l e v e l o f c l e a n - u p and i t s l e v e r a g e o v e r o t h e r r e s p o n s i b l e c o m p a n i e s . I n d u s t r y , on t h e o t h e r h a n d , w a n t e d t o g e t on w i t h r e a s o n a b l e c l e a n - u p , b u t d i d n o t want t o l e a v e EPA and J u s t i c e w i t h t h e d i s c r e t i o n and l e v e r a g e o f S. 1480. The f e a r was t h a t t h e y w o u l d i n s i s t on m a s s i v e l y e x p e n s i v e and unnecessary clean-up. As t h e W h i t e House d i s c u s s i o n wore o n , an i d e a d e v e l o p e d t o b r i d g e b e t w e e n t h e p o l a r i z e d p o s i t i o n s . The i d e a was t h a t t h e N a t i o n a l C o n t i n g e n c y P l a n (NCP) f o r h a n d l i n g s p i l l s u n d e r S e c t i o n 311 o f t h e C l e a n W a t e r A c t c o u l d be e x p a n d e d and t a i l o r e d t o p r o v i d e a v e h i c l e f o r m a k i n g r e a s o n a b l e and p r i o r i t i z e d d e c i s i o n s a b o u t r e s p o n s e a c t i o n s and t h e l e v e l o f c l e a n - u p . The r e v i s e d NCP i d e a was w r i t t e n up i n s e v e r a l t e n t a t i v e d r a f t s , b u t t h e W h i t e House m e e t i n g s and t h e W h i t e House e f f o r t b r o k e up a f t e r Jimmy C a r t e r l o s t t h e 1980 election. When t h e Lame Duck s e s s i o n o f t h e 9 6 t h C o n g r e s s opened i n l a t e November, 1980, t h e S e n a t e s t a f f t r i e d o n c e more t o move a Superfund b i l l . T h i s t i m e t h e y o f f e r e d a compromise s u b s t i t u t e w h i c h u s e d a r e v i s e d N a t i o n a l C o n t i n g e n c y P l a n as t h e c e n t e r o f an i n t e g r a t e d scheme t o d e f i n e a r e a s o n a b l e l e v e l o f c l e a n - u p . This s u b s t i t u t e was u l t i m a t e l y e n a c t e d w i t h few amendments. D e s c r i p t i o n o f Key

Superfund P r o v i s i o n s

S i n c e i t was h a s t i l y p u t t o g e t h e r and r e c e i v e d l i t t l e a n a l y t i c a l c o n s i d e r a t i o n , t h e r e a r e many t e c h n i c a l f l a w s and t h e r e w i l l be much room f o r i n t e r p r e t a t i o n . N e v e r t h e l e s s , t h e b i l l as p a s s e d c o n t a i n s an i n t e g r a t e d s e t o f r e s p o n s e p r o v i s i o n s c e n t e r e d on a

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

1.

FROST

Revised National Contingency Plan

3

r e v i s e d N a t i o n a l Contingency P l a n which c a l l s f o r r i s k assessment and c o s t e f f e c t i v e n e s s . S e c t i o n 105 d i r e c t s t h e P r e s i d e n t t o r e v i s e t h e N a t i o n a l Cont i n g e n c y P l a n (NCP) ( f o r m e r l y l i m i t e d t o emergency r e s p o n s e u n d e r S e c t i o n 311 o f t h e C l e a n W a t e r A c t ) t o i n c l u d e a new " h a z a r d o u s substance response p l a n " s e t t i n g o u t p r o c e d u r e s and s t a n d a r d s f o r r e s p o n s e a c t i o n s . T h i s r e v i s i o n may b e a d o p t e d o n l y a f t e r n o t i c e and o p p o r t u n i t y f o r p u b l i c comment. Among t h e e l e m e n t s w h i c h must b e i n c l u d e d i n t h e r e v i s e d NCP u n d e r t h i s s e c t i o n a r e methods and c r i t e r i a f o r d e t e r m i n i n g t h e a p p r o p r i a t e e x t e n t o f e i t h e r removal o r r e m e d i a l measures ( S e c t i o n 105(3)). The NCP must a l s o c o n t a i n means f o r a s s u r i n g t h a t "remed i a l " a c t i o n measures, as d i s t i n c t from t h e s h o r t - t e r m "removal" measures, a r e " c o s t - e f f e c t i v e " ( S e c t i o n 105(7)). F i n a l l y , Section 105(8)(A) r e q u i r e criteri f o determinin prioritie which a r e " b a s e d upon r e l a t i v f a r e o r the environment, c r i t e r i a b e u s e d t o d e v e l o p a n a t i o n a l p r i o r i t y l i s t o f 400 s i t e s . I m p o r t a n t l y , t h e p e n u l t i m a t e s e n t e n c e o f S e c t i o n 105 r e q u i r e s t h a t , f o l l o w i n g p u b l i c a t i o n o f t h e r e v i s e d NCP, " t h e r e s p o n s e t o ... h a z a r d o u s s u b s t a n c e s r e l e a s e s s h a l l , t o t h e g r e a t e s t e x t e n t p o s s i b l e , be i n a c c o r d a n c e w i t h t h e p r o v i s i o n s o f t h e p l a n . " S e c t i o n 104 o f S u p e r f u n d a u t h o r i z e s t h e P r e s i d e n t t o remove o r remedy any r e l e a s e o r t h r e a t e n e d r e l e a s e t o t h e e n v i r o n m e n t o f any h a z a r d o u s s u b s t a n c e , a s d e f i n e d i n S e c t i o n 1 0 1 ( 1 4 ) o f t h e A c t , o r a n y o t h e r c o n t a i n m e n t w h i c h may p r e s e n t a n " i m m i n e n t a n d s u b s t a n t i a l d a n g e r " t o t h e p u b l i c h e a l t h o r t h e e n v i r o n m e n t . He may accomplish t h i s by removing t h e hazardous substance, o r by t a k i n g "any o t h e r r e s p o n s e m e a s u r e , " u n l e s s h e d e t e r m i n e d t h a t s u c h r e m o v a l o r remedy w i l l b e done b y some r e s p o n s i b l e p e r s o n . Regardl e s s o f which course the President chooses, S e c t i o n 104(a)(1) s t a t e s t h a t i t must b e " c o n s i s t e n t w i t h t h e n a t i o n a l c o n t i n g e n c y plan." S e c t i o n 111(a) d i r e c t s t h a t t h e c o s t s o f such f e d e r a l response be borne by t h e response fund c r e a t e d by t h e A c t . S e c t i o n 1 0 6 , e n t i t l e d "Abatement A c t i o n , " i s t h e e n f o r c e m e n t section. U n d e r s u b s e c t i o n ( a ) , when t h e P r e s i d e n t d e t e r m i n e s t h a t an a c t u a l o r t h r e a t e n e d r e l e a s e o f a h a z a r d o u s s u b s t a n c e p r e s e n t s "an i m m i n e n t a n d s u b s t a n t i a l endangerment t o t h e p u b l i c h e a l t h o r e n v i r o n m e n t , " he may d i r e c t t h e A t t o r n e y G e n e r a l t o b r i n g a n a c t i o n i n a f e d e r a l d i s t r i c t court (against u n s p e c i f i e d persons) t o o b t a i n "such r e l i e f a s t h e p u b l i c i n t e r e s t and e q u i t i e s o f t h e c a s e may r e q u i r e . " The P r e s i d e n t a l s o may t a k e o t h e r u n s p e c i f i e d a c t i o n , i n c l u d i n g i s s u i n g such orders ( t o u n s p e c i f i e d persons) as may b e " n e c e s s a r y t o p r o t e c t p u b l i c h e a l t h a n d w e l f a r e a n d t h e environment." S e c t i o n 1 0 6 ( c ) r e q u i r e s EPA, i n c o n s u l t a t i o n w i t h t h e A t t o r ney G e n e r a l , t o e s t a b l i s h a n d p u b l i s h g u i d e l i n e s f o r u s i n g t h e response a u t h o r i t i e s under s u b s e c t i o n ( a ) . U n l i k e t h e r e v i s i o n o f t h e NCP d i r e c t e d u n d e r S e c t i o n 105, t h e r e i s no e x p r e s s s t a t u t o r y r e q u i r e m e n t f o r p u b l i c n o t i c e a n d comment p r i o r t o a d o p t i o n o f t h e

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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guidelines. T h e s e g u i d e l i n e s a r e l i n k e d t o t h e NCP by t h e d i r e c t i o n i n S e c t i o n 106(c) t h a t the g u i d e l i n e s " t o the e x t e n t p r a c t i c a b l e be c o n s i s t e n t w i t h t h e n a t u r a l h a z a r d o u s s u b s t a n c e r e s p o n s e plan." A p p l i c a t i o n o f t h e NCP

t o P r i v a t e Clean-Up

The s t a t u t o r y p r o v i s i o n s h a v e f a i l e d t o end t h e controversy o v e r r i s k a s s e s s m e n t . From t h e o u t s e t some e n v i r o n m e n t a l g r o u p s have argued t h a t the r i s k assessment, c o s t - e f f e c t i v e n e s s p r o v i s i o n s o f t h e NCP a r e meant t o a p p l y o n l y t o g o v e r n m e n t - f i n a n c e d c l e a n - u p u n d e r S e c t i o n 104 and do n o t a p p l y t o p r i v a t e c l e a n - u p u n d e r S e c t i o n 106 o r t o v o l u n t a r y p r i v a t e c l e a n - u p ( 4 ) . Instead, t h e y a d v o c a t e d t h a t p r i v a t e c l e a n - u p be h a n d l e d on a s e p a r a t e t r a c k o r i e n t e d towards p l a i n t s w h i c h w o u l d be T h i s i n t e r p r e t a t i o n o f t h e NCP as b e i n g l i m i t e d t o g o v e r n m e n t f i n a n c e d c l e a n - u p i s c o m p l e t e l y a t odds w i t h t h e s t a t u t o r y f r a m e work. S e c t i o n 5 i t s e l f s t a t e s i t s u n q u a l i f i e d a p p l i c a b i l i t y t o " t h e r e s p o n s e t o ... h a z a r d o u s s u b s t a n c e r e l e a s e s . " Both Sections 104 and 106 i n v o l v e t h e NCP a s t h e r e f e r e n c e p o i n t f o r r e s p o n s e o r clean-up. S e c t i o n s 104, 105 and 106 a l l work t o g e t h e r , w i t h S e c t i o n 105 g i v i n g t h e f r a m e w o r k f o r d e t e r m i n i n g p r i o r i t i e s and extent of clean-up. F u r t h e r i n d i c a t i o n o f t h e c e n t r a l i t y o f S e c t i o n 105 o f t h e NCP i s f o u n d i n S e c t i o n 107. S e c t i o n 107 o u t l i n e s t h e o n l y p r i n c i p l e s of l i a b i l i t y i n c l u d e d i n Superfund. I t states, without d i s t i n g u i s h i n g b e t w e e n f u n d - and p r i v a t e l y - f i n a n c e d c l e a n - u p s , t h a t p a r t i e s w i l l be l i a b l e o n l y f o r c o s t s w h i c h a r e " c o n s i s t e n t w i t h " o r i n some c a s e s " n o t i n c o n s i s t e n t w i t h " t h e NCP (Section 107(a)(4)(A)-(B)). Although the l e g i s l a t i v e h i s t o r y i s sketchy, Senator S t a f f o r d , one o f t h e p r i n c i p a l s p o n s o r s o f t h e f i n a l s u b s t i t u t e , r e c o g n i z e d t h a t p r i v a t e c l e a n - u p and o r d e r s f o r p r i v a t e l y - f i n a n c e d c l e a n - u p u n d e r S e c t i o n 106 w o u l d be g o v e r n e d by t h e NCP. In f l o o r debate s h o r t l y b e f o r e CERCLA's e n a c t m e n t , he d e s c r i b e d c i r c u m s t a n c e s under which c o u r t s might r e v i e w such o r d e r s . He s t a t e d t h a t "we w o u l d e x p e c t t h e c o u r t s t o e x a m i n e t h e p a r t i c u l a r o r d e r s ... t o d e t e r m i n e w h e t h e r t h e y were p r o p e r , g i v e n t h e s t a n d a r d s o f t h e a c t and o f t h e N a t i o n a l C o n t i n g e n c y P l a n " (126 Cong. Rec. S. 15008 ( d a i l y e d . November 24, 1 9 8 0 ) , e m p h a s i s a d d e d ) . As i t s t a n d s now t h e EPA has made t h e NCP a p p l i c a b l e t o p r i v a t e c l e a n - u p as w e l l as g o v e r n m e n t a l c l e a n - u p i n i t s P r o p o s e d R e v i s i o n s t o t h e N a t i o n a l C o n t i n g e n c y P l a n (_5) . I f t h e NCP i s u l t i m a t e l y p r o m u l g a t e d s u b s t a n t i a l l y as p r o p o s e d , i t i s l i k e l y t h a t t h e U n i t e d S t a t e s C o u r t o f A p p e a l s f o r t h e D i s t r i c t o f Columb i a w i l l u p h o l d i t as w i t h i n E P A s d i s c r e t i o n . I n t h e meantime a t t e n t i o n o f b o t h i n d u s t r y and e n v i r o n m e n t a l g r o u p s has f o c u s e d on the d e t a i l s of the Proposed R e v i s i o n s . 1

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R i s k A s s e s s m e n t a n d Remedy S e l e c t i o n u n d e r t h e P r o p o s e d NCP The p r o p o s e d NCP r e c o g n i z e s t h e s t a t u t o r y mandate i n S e c t i o n 105(8) t o d e v e l o p r i s k a s s e s s m e n t c r i t e r i a and a N a t i o n a l P r i o r i t y L i s t by l i m i t i n g "remedial" a c t i o n s t o r e l e a s e s on t h e N a t i o n a l P r i o r i t y L i s t ( §300.67 ( a ) ) . T h i s w i l l p u t t e e t h i n t h e mandate o f S e c t i o n 105(8) and w i l l a s s u r e t h e i m p o r t a n c e o f t h e r i s k a n a l y s i s / p r i o r i t i z a t i o n process. EPA h a s n o t s p e c i f i e d , h o w e v e r , t h a t t h e N a t i o n a l P r i o r i t y L i s t w i l l be p a r t o f t h e N a t i o n a l C o n t i n g e n c y P l a n , a n d t h e r e i s s t i l l c o n t r o v e r s y o v e r t h e p r o c e d u r e f o r m a k i n g up t h e l i s t a n d the f u n c t i o n o f t h e l i s t . The M i t r e M o d e l . W i t h t h e a s s i s t a n c e o f t h e M i t r e C o r p o r a t i o n , EPA h a s d e v e l o p e superfund s i t e s by Sectio s t r a i g h t f o r w a r d model w h i c h w i l l rank s i t e s l a r g e l y on t h e b a s i s of e a s i l y obtainable information. F i v e pathways o f exposure (ground w a t e r , s u r f a c e w a t e r , a i r , d i r e c t c o n t a c t , a n d e x p l o s i o n ) w i l l be c o n s i d e r e d . The p r o b a b i l i t y a n d m a g n i t u d e o f a n a d v e r s e e v e n t w i l l be e s t i m a t e d f o r e a c h p a t h w a y t o a r r i v e a t a n o v e r a l l r i s k estimate. C r i t i c i s m s o f t h e M i t r e Model r u n from t h e f e a r t h a t i t w i l l n o t be s u f f i c i e n t l y p r e c i s e o r a n a l y t i c a l t o t h e c o n c e r n t h a t i t makes no p r o v i s i o n f o r u t i l i z i n g e x t r a i n f o r m a t i o n when i t i s r e a d i l y a v a i l a b l e and i s h i g h l y r e l e v a n t . I t i s b e y o n d t h e s c o p e o f t h i s p a p e r t o examine t h e M i t r e Model i n d e t a i l . Rather, i t i s s u f f i c i e n t t o note t h a t there i s m e r i t t o EPA s d e c i s i o n t o adopt a p r a c t i c a l r i s k assessment/prio r i t i z a t i o n a p p r o a c h . I f a f u l l r i s k a n a l y s i s h a d t o be c o n d u c t e d a t e v e r y s i t e , EPA w o u l d s p e n d a l l i t s r e s o u r c e s o n a s s e s s m e n t a n d w o u l d h a v e d i f f i c u l t y k n o w i n g where t o s t a r t t h e c l e a n - u p . On t h e o t h e r h a n d , t h e m o d e l must b e f l e x i b l e enough t o t a k e i n t o a c c o u n t t h e i n f o r m a t i o n w h i c h does e x i s t r e g a r d i n g a p a r t i c u l a r s i t e s o t h a t t h e r i s k assessment c a n be a s a c c u r a t e a s p r a c t i c a l l y p o s sible. A d d i t i o n a l r e f i n e m e n t o f t h e M i t r e M o d e l i s e x p e c t e d when t h e f i n a l NCP i s p u b l i s h e d . I n a d d i t i o n , EPA i s e x p e c t e d t o g i v e some g u i d a n c e i n t h e f i n a l NCP a s t o how t h e r a n k i n g w i l l work. Will EPA go s t r i c t l y a c c o r d i n g t o n u m e r i c a l p r i o r i t i e s o r work b y g r o u p s o r c l u s t e r s o f p r i o r i t y a s s u g g e s t e d i n t h e NCP? W i l l t h e s t a t e s have a s i g n i f i c a n t r o l e i n d e v e l o p i n g t h e p r i o r i t i e s ? What r i g h t s w i l l p r i v a t e p a r t i e s have t o c h a l l e n g e t h e placement o f t h e i r s i t e on the p r i o r i t y l i s t ? A l l o f t h e s e q u e s t i o n s w i l l have t o be a n s w e r e d a t some p o i n t . 1

S e l e c t i o n o f Remedy. R i s k a s s e s s m e n t u n d e r t h e S e c t i o n 105 scheme f o r t h e NCP i s e x p l i c i t l y r e q u i r e d o n l y i n c o n n e c t i o n w i t h the p r i o r i t i z a t i o n p r o c e s s under S e c t i o n 105(8). After p r i o r i t i z a t i o n o n t h e b a s i s o f r i s k , t h e k e y i s s u e i s s e l e c t i o n o f remedy.

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S e c t i o n 105(3) r e q u i r e s "methods and c r i t e r i a " f o r s e l e c t i o n o f remedy, and S e c t i o n 105(7) r e q u i r e s t h a t t h e NCP c o n t a i n means f o r a s s e s s i n g t h a t r e m e d i a l measures are " c o s t e f f e c t i v e . " T h e r e i s an a d d i t i o n a l r e q u i r e m e n t when t h e P r e s i d e n t u s e s S u p e r f u n d money f o r a r e m e d i a l r e s p o n s e . S e c t i o n 104(c)(4) r e q u i r e s t h a t the P r e s i d e n t "balance between the need f o r p r o t e c t i o n o f p u b l i c h e a l t h and w e l f a r e and t h e e n v i r o n m e n t a t t h e f a c i l i t y u n d e r c o n s i d e r a t i o n and t h e a v a i l a b i l i t y o f amounts f r o m the fund." The e x p l i c i t c o s t / b e n e f i t b a l a n c i n g r e q u i r e m e n t o f S e c t i o n 1 0 4 ( c ) (4) i s n o t a p p l i c a b l e t o p r i v a t e r e s p o n s e u n d e r t h e NCP. Thus, once r i s k i s t a k e n i n t o a c c o u n t i n the p r i o r i t i z a t i o n p r o c e s s , t h e EPA has c o n s i d e r a b l e l a t i t u d e i n d e v i s i n g methods and c r i t e r i a f o r remedy s e l e c t i o n , w i t h t h e m a j o r s u b s t a n t i v e r e q u i r e ment b e i n g c o s t e f f e c t i v e n e s i n many c a s e s t h e M i t r a d e q u a t e f o r remedy s e l e c t i o n , and a more d e t a i l e d a s s e s s m e n t w i l l be n e c e s s a r y . T h e r e has b e e n much d i f f e r e n c e o f o p i n i o n r e g a r d i n g a p p r o p r i a t e methods and c r i t e r i a f o r remedy s e l e c t i o n . Annex X I I I o f t h e May 8, 1981 s t a f f d r a f t o f t h e NCP c a l l e d f o r c l e a n - u p t o t h e l e v e l o f F e d e r a l and S t a t e w a t e r q u a l i t y s t a n d a r d s , F e d e r a l w a t e r q u a l i t y c r i t e r i a , F e d e r a l d r i n k i n g w a t e r s t a n d a r d s , and n a t i o n a l a m b i e n t a i r q u a l i t y s t a n d a r d s r e g a r d l e s s o f w h e t h e r t h e r e was any s u b s t a n t i a l e x p o s u r e o r r i s k f r o m t h e r e l e a s e t o be r e m e d i e d . The c o s t e f f e c t i v e n e s s r e q u i r e m e n t was a p p l i e d o n l y by c a l l i n g f o r c o s t e f f e c t i v e methods o f r e a c h i n g t h e s t a n d a r d s i m p o s e d . I n d u s t r y c r i t i c i z e d t h i s a p p r o a c h on a number o f g r o u n d s (6). W a t e r q u a l i t y c r i t e r i a and n a t i o n a l a m b i e n t a i r q u a l i t y s t a n d a r d s were n e v e r d e s i g n e d n o r c a n t h e y be s e n s i b l y u s e d t o s e t s t a n d a r d s f o r i n d i v i d u a l r e l e a s e s . W a t e r q u a l i t y s t a n d a r d s and F e d e r a l d r i n k i n g w a t e r s t a n d a r d s , a l t h o u g h more a p p r o p r i a t e f o r s u r f a c e w a t e r o r a t - t h e - t a p c o n s i d e r a t i o n , h a v e b e e n s e t f o r v e r y few o f t h e h a z a r d o u s compounds w h i c h may be e n c o u n t e r e d a t an o l d dumpsite. Use o f p r e - e x i s t i n g s t a n d a r d s and c r i t e r i a t o s e t m a n d a t o r y l e v e l s o f c l e a n - u p w o u l d p r e c l u d e any s i t e - b y - s i t e c o n s i d e r a t i o n o f e x p o s u r e and r i s k , and c o u l d r e s u l t i n huge c l e a n - u p c o s t s where t h e r i s k s were i n c o n s e q u e n t i a l . I n a d d i t i o n , as a f o r m a l m a t t e r , t h e F e d e r a l w a t e r q u a l i t y c r i t e r i a f o r many s u b s t a n c e s h a v e b e e n l e f t a t z e r o p e n d i n g f u l l s c i e n t i f i c and r i s k a s s e s s m e n t , and use o f t h e s e c r i t e r i a w o u l d r e q u i r e a z e r o - r e l e a s e c l e a n - u p i n a s i t u a t i o n w h i c h i m p o s e d no s i g n i f i c a n t r i s k i n t h e f i r s t p l a c e (7). The A d m i n i s t r a t o r o f EPA has t a k e n t h e p o s i t i o n t h a t " e a c h r e l e a s e p r e s e n t s a unique s i t u a t i o n because of i t s d i v e r s e chara c t e r i s t i c s ." {8) B a s e d on t h i s t h e o p t i o n o f r e q u i r i n g c l e a n - u p t o f e d e r a l and s t a t e s t a n d a r d s and c r i t e r i a was r e j e c t e d :

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"One o p t i o n was t o r e q u i r e c l e a n u p t o l e v e l s t h a t met F e d e r a l and S t a t e s t a n d a r d s o r w a t e r q u a l i t y c r i teria. The A g e n c y h a s d e c i d e d t h a t s u c h a r i g i d r e q u i r e ment w o u l d impose t h e u s e o f p o t e n t i a l l y i n a p p r o p r i a t e l e v e l s o f cleanup t h a t would not a l l o w c o n s i d e r a t i o n o f i n d i v i d u a l c i r c u m s t a n c e s a t each r e l e a s e . Any approp r i a t e s t a n d a r d o r c r i t e r i a w i l l be c o n s i d e r e d i n d e t e r mining the cleanup l e v e l o f a p a r t i c u l a r r e l e a s e , along w i t h o t h e r t e c h n o l o g i c a l and e n v i r o n m e n t a l f a c t o r s . " (9) EPA a l s o c o n s i d e r e d f o r m a l c o s t - b e n e f i t a n a l y s i s a s a d e c i s i o n m a k i n g t o o l and r e j e c t e d i t b e c a u s e i t w o u l d " m e r e l y r e s u l t i n r i g i d c a l c u l a t i o n s t h a t w o u l d f o r e c l o s e any f l e x i b i l i t y i n t h e u l t i m a t e d e c i s i o n m a k i n g . " (10) The d e c i s i o n m a k i n t o t h e NCP i s a c a s e - b y - c a s t i o n must b e g i v e n t o a r a n g e o f a l t e r n a t i v e s w h i c h have b e e n s e l e c t e d and a n a l y z e d . C o s t , f e a s i b i l i t y , a d e q u a c y , r e l i a b i l i t y , and p o t e n t i a l a d v e r s e i m p a c t s o n h e a l t h o r t h e e n v i r o n m e n t must be a n a l y z e d . A n y a p p r o p r i a t e F e d e r a l and S t a t e s t a n d a r d s and c r i t e r i a a r e t o be c o n s i d e r e d . F i n a l l y , under proposed S e c t i o n 300.67 ( j ) t h e l e a d a g e n c y i s " t o c h o o s e t h e most c o s t e f f e c t i v e r e m e d i a l a l t e r n a t i v e w h i c h e f f e c t i v e l y m i n i m i z e s and m i t i g a t e s t h e d a n g e r and p r o v i d e s a d e q u a t e p r o t e c t i o n o f p u b l i c h e a l t h , w e l f a r e , and t h e e n v i r o n m e n t . " (11) The E n v i r o n m e n t a l D e f e n s e Fund h a s o b j e c t e d t o t h e l a c k o f s t a n d a r d s c r i t e r i a o r g o a l s i n t h e P r o p o s e d NCP and c o n s i d e r s t h e p r o p o s e d c a s e - b y - c a s e a p p r o a c h t o o c o s t o r i e n t e d . (12) Nonethel e s s , the proposed approach p r o v i d e s f o r assessment o f the r i s k s t o t h e p u b l i c h e a l t h and t h e e n v i r o n m e n t , and c o n s i d e r a t i o n o f the impact o f such r i s k i s r e q u i r e d i n s e l e c t i n g the f i n a l a l t e r n a t i v e . A c c o r d i n g l y , r i s k a s s e s s m e n t s h o u l d b e most i m p o r t a n t i n decisionmaking on the major Superfund s i t e s . Professional experts i n t h i s a r e a w i l l have a g r e a t c h a l l e n g e t o d e v e l o p t h e i r r i s k a s s e s s m e n t c a p a c i t y and m e t h o d o l o g y o n a c a s e - b y - c a s e b a s i s s o t h a t i t can i n d e e d prove u s e f u l i n s e l e c t i n g r e m e d i a l a l t e r n a t i v e s u n d e r t h e NCP. Conclusion 1

I n S u p e r f u n d s S e c t i o n 105 r e q u i r e m e n t f o r a R e v i s e d NCP, C o n g r e s s mandated a scheme f o r r e s p o n d i n g t o r e l e a s e s o f h a z a r d o u s materials. F o r o l d dump s i t e s r e s p o n s e s t a r t s w i t h a s u r v e y and p r i o r i t i z a t i o n o f s i t e s based on r i s k assessment. After p r i o r i t i z a t i o n the focus turns t o s e l e c t i o n o f c o s t - e f f e c t i v e remedies w h i c h w i l l a d e q u a t e l y p r o t e c t t h e p u b l i c h e a l t h and w e l f a r e and the environment. I n r e v i s i n g t h e NCP, EPA i s engaged i n a p i o n e e r i n g e f f o r t t o d e v e l o p a p r a c t i c a l and e f f e c t i v e s i t e a s s e s s ment m o d e l . A f t e r p r i o r i t i z a t i o n a d d i t i o n a l assessment w i l l o f t e n

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be r e q u i r e d t o s e l e c t a remedy. F o r m a l c o s t - b e n e f i t a n a l y s i s w i l l n o t be u s e d , and t h e remedy s e l e c t i o n r i s k a s s e s s m e n t w i l l be done on a c a s e - b y - c a s e b a s i s . I n c a n be e x p e c t e d t h a t E P A s e x p e r i e n c e i n t h i s c a s e - b y - c a s e a p p r o a c h w i l l be i n v a l u a b l e i n d e v e l o p i n g f u t u r e r i s k assessment methodology. 1

Literature

Cited

1.

T e s t i m o n y o f D r . L o u i s F e r n a n d e z on behalf o f C h e m i c a l Manufacturers Association, H e a r i n g s on S. 1480 b e f o r e t h e S e n a t e F i n a n c e C o m m i t t e e , 9 6 t h C o n g r e s s , 2d Session, September 1 1 , 1980. 2. R e p o r t No. 96-848 3. H. R. R e p o r t 96-1016 4. T h i s d o u b l e track a p p r o a c h was reflected i n Annex XIII o f the first, May 8, 1981, informal EPA draft of t h e R e v i s e d NCP. S e c t i o n 300.2 o f that annex specifically provided that r e s p o n s e action w o u l d n o t be g o v e r n e d by t h e NCP. 5. 47 F e d . Reg. 10972-10995, M a r c h 12, 1982. 6. Chemical Manufacturers Association Comments on t h e Draft Revision t o t h e National C o n t i n g e n c y Plan, J u n e 30, 1981, p p . 40-46. 7. CMA Comments on t h e P r o p o s e d Revisions to the National Contingency Plan, April 28, 1982, pp. 3-5. 8. Preamble t o Proposed Revisions t o the National Contingency Plan, 47 F e d . Reg. 10972, 10977, M a r c h 12, 1982. 9. Id., a t 1078. 10. Ibid. 11. I d . , a t 10977. 12. H a z a r d o u s Waste News, May 17, 1982, 4, No. 20, p p . 154-155. RECEIVED July 27,

1982.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

2 Case Studies of Hazardous Waste Problems in Louisiana WILLIAM B. D E V I L L E Louisiana Department of Natural Resources, Baton Rouge, L A 70804

The S t a t e ' s experience i n d e a l i n g with hazardous w a s t e managemen complexity of i n t e r a c t i o n e c o n o m i c and political e l e m e n t s o f problems and actions. C u r r e n t f e d e r a l t e c h n i c a l foundations f o r regulatory or " S u p e r f u n d " decisions and actions provide only a rudimentary basis f o r program functions at the State level; t h i s r e s u l t s i n a tendency e i t h e r to exaggerate o r m i n i m i z e the l e v e l of a c t u a l problems, and requires additional technical information to i m p r o v e a n a l y s i s of s p e c i f i c cases before a c t i o n . This paper provides an a n a l y s i s of the State's approaches to filling i n gaps i n the scientific and technical foundations f o r hazardous waste d e c i s i o n s by means of s e l e c t e d case histories. These case histories include (1) the approach to regulatory definitions of hazardous wastes, with e m p h a s i s on toxic properties; (2) the r e g u l a t o r y a p p r o a c h t o s t a n d a r d s and criteria for facilities m a n a g i n g h a z a r d o u s w a s t e s ; and (3) development of cleanup r e s p o n s e s t o "abandoned" waste s i t e s (with comments on the use of the ' M i t r e Model' f o r ranking such sites). The paper supports the conclusions that (a) r a t i o n a l d e c i s i o n s can be made (though with some difficulty) in public p o l i c i e s r e l a t e d to the case histories, and (b) an a g e n d a f o r i m p r o v i n g the scientific and t e c h n i c a l components of hazardous waste and "Superfund" d e c i s i o n s i s now apparent and can be suggested i n broad o u t l i n e . T h i s p a p e r p r e s e n t s t h e a u t h o r ' s p e r s o n a l o b s e r v a t i o n s and c o n c l u s i o n s d e r i v e d f r o m e x p e r i e n c e i n h a z a r d o u s waste r e g u l a t o r y p r o g r a m development a t t h e s t a t e government l e v e l . Over t h e c o u r s e o f t h e p a s t s e v e r a l y e a r s t h e S t a t e o f L o u i s i a n a h a s been d e v e l o p i n g a v e r y complex and c o m p r e h e n s i v e h a z a r d o u s 0097-6156/82/0204-0009$06.00/0 © 1982 American Chemical Society

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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w a s t e r e g u l a t o r y p r o g r a m f o r p r o t e c t i o n of p u b l i c h e a l t h and the environment. T h e s e r e g u l a t o r y e f f o r t s were a l s o d e s i g n e d t o meet the g o a l s of the F e d e r a l R e s o u r c e C o n s e r v a t i o n and R e c o v e r y A c t f o r c o n t r o l of h a z a r d o u s w a s t e s ; i n d e e d , L o u i s i a n a was one of the f i r s t s t a t e s to r e c e i v e i n t e r i m a u t h o r i z a t i o n under the Federal Act. A m a j o r i m p e t u s t o t h e p a s s a g e i n 1978 o f the s t a t e l e g i s l a t i o n a u t h o r i z i n g t h e new h a z a r d o u s w a s t e p r o g r a m was the recognition that Louisiana, as one o f the c e n t e r s of p e t r o c h e m i c a l p r o d u c t i o n i n t h e n a t i o n , needed s t r i c t c o n t r o l s o v e r m a n a g e m e n t o f t h e i n e v i t a b l e w a s t e s p r o d u c e d by s u c h industry. T h e r e were a l s o p a s t p r o b l e m s t o be c l e a n e d up. So a t w o - f o l d e f f o r t was needed: (1) d e v e l o p m e n t of a new r e g u l a t o r y p r o g r a m f o r p r o s p e c t i v e c o n t r o l s o v e r f u t u r e management of h a z a r d o u s w a s t e s i n the s t a t e ; and (2) d e v e l o p m e n t of s t r a t e g i e s and p r o g r a m s to i d e n t i f management p r a c t i c e s i T h e s e e f f o r t s h a v e b e e n c o m p l i c a t e d , to a s i g n i f i c a n t d e g r e e , by t h e f a c t t h a t t h e y h a v e b e e n m o v i n g forward concurrently with — and o f t e n i n advance of — similar efforts a t the F e d e r a l l e v e l . The

inherent

complexity

of such a r e g u l a t o r y program

P a r t i c u l a r l y a t a m e e t i n g s u c h as t h i s , w h i c h f o c u s e s p r i n c i p a l l y on s c i e n t i f i c and t e c h n i c a l m a t t e r s , i t must be remembered t h a t a r e g u l a t o r y p r o g r a m i s a l e g a l device t o impose c e r t a i n c o n s t r a i n t s on a c t i v i t i e s i n a s p e c i f i e d segment of society. The r e g u l a t o r y p r o g r a m i s p e r m i s s i v e as r e g a r d s c e r t a i n a c t i v i t i e s w h i c h may be c o n d u c t e d w i t h i n approved b o u n d a r i e s , e.g., d i s p o s a l of a w a s t e i n a f a c i l i t y t h a t has been permitted i n a c c o r d a n c e w i t h t h e r e q u i r e m e n t s and p r o c e d u r e s of the p r o g r a m . The r e g u l a t o r y p r o g r a m a l s o f o r b i d s o t h e r a c t i o n s , e.g., " m i d n i g h t dumping" of h a z a r d o u s w a s t e s , and provides l e g a l mechanisms and p e n a l t i e s f o r e n f o r c i n g a g a i n s t those a c t i o n s that are p r o h i b i t e d . The ' f i t ' of s c i e n c e and t e c h n o l o g y i n t h e program. Science a n d t e c h n o l o g y p l a y i m p o r t a n t b u t , i n f a c t , somewhat s e c o n d a r y r o l e s i n t h e d e v e l o p m e n t of a r e g u l a t o r y p r o g r a m s u c h as t h a t d e a l i n g w i t h h a z a r d o u s w a s t e s . The f i r s t s u c h r o l e i s i n problem d e f i n i t i o n : what a r e the c h a r a c t e r i s t i c s t h a t may be used to i d e n t i f y those wastes f o r which r e g u l a t o r y c o n t r o l s are mandated? The second g e n e r a l r o l e calling for s c i e n t i f i c i n f o r m a t i o n and d e c i s i o n s i s , what a r e the l e v e l s of r i s k s b e l o w which the regulatory system is permissive, i.e., s t a n d a r d - s e t t i n g f o r a l l o w e d p r a c t i c e s s u c h as i n c i n e r a t i o n o r l a n d - f i l l i n g of hazardous w a s t e s . The t h i r d g e n e r a l r o l e i s i n m e a s u r e m e n t o f p a r a m e t e r s a s s t i p u l a t e d by the r e g u l a t o r y p r o g r a m t o a l l o w d e c i s i o n s t o be made as t o w h e t h e r o r not any

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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g i v e n h a z a r d o u s w a s t e management a c t i v i t y i s a l l o w e d . Finally, t h e r e must be a c h a i n o f t e c h n i c a l e v a l u a t i o n s and d e c i s i o n s as t o s u i t a b l e t e c h n o l o g y a n d o p e r a t i n g c o n d i t i o n s f o r management o f w a s t e s i n a n y g i v e n c a s e , t h a t w i l l meet t h e c o n s t r a i n t s i m p o s e d b y t h e s t a n d a r d s and c r i t e r i a o f t h e r e g u l a t o r y p r o g r a m . E a c h o f t h e s e r o l e s p l a c e s s t r i n g e n t demands on t h e a b i l i t y o f s c i e n c e and t e c h n o l o g y t o s u p p l y i n f o r m a t i o n and a n s w e r s . I have characterized t h e s c i e n t i f i c and t e c h n i c a l components o f t h e r e g u l a t o r y s y s t e m a s p l a y i n g a s e c o n d a r y r o l e i n t h e r e g u l a t o r y development, because i n f a c t they a r e not the d r i v i n g f o r c e i n development. Thus, i t i s e n t i r e l y p o s s i b l e f o r t h e s y s t e m t o move f o r w a r d i n t h e f a c e o f p a r t i a l s c i e n t i f i c and t e c h n i c a l i n p u t , o r e v e n , i n t h e w o r s t c a s e , i n a d e q u a t e and u n s a t i s f a c t o r y s c i e n t i f i c and t e c h n i c a l i n p u t and d e c i s i o n s . I n p r a c t i c e , th development f th regulator syste will t e n d t o move f o r w a r d r e g a r d l e s technology t o supply th D e c i s i o n s must be made a s t o what w a s t e m a t e r i a l s a r e i d e n t i f i e d f o r r e g u l a t o r y c o n t r o l , what p r a c t i c e s a r e a c c e p t a b l e , and what measurements a r e t o be u s e d f o r p u r p o s e s o f e n f o r c e m e n t o f t h e regulations. Perhaps the c h i e f d r i v i n g f o r c e r e s u l t i n g from the n a t u r e o f t h e r e g u l a t o r y p r o g r a m a s a l e g a l 'machine' i s t o w a r d l e g a l c l a r i t y and s i m p l i c i t y o f e n f o r c e m e n t ; t h i s d r i v i n g f o r c e c a n s e v e r e l y t e s t t h e a b i l i t y o f t h e s c i e n t i f i c and t e c h n i c a l community t o supply t h e i n f o r m a t i o n and answers needed t o p r o v i d e sound s u p p o r t t o t h e r e g u l a t o r y p r o g r a m . What i s a h a z a r d o u s w a s t e —

and how do we t e s t f o r i t ?

Louisiana's h a z a r d o u s w a s t e r e g u l a t i o n s were a d o p t e d and became e f f e c t i v e i n 1979, w e l l i n advance o f p r o m u l g a t i o n o f t h e Federal regulations. One o f t h e c r i t i c a l p r o b l e m s we f a c e d was d e f i n i n g j u s t what i t was t h a t t h e r e g u l a t i o n s were supposed t o c o n t r o l , w i t h t h e a d d i t i o n a l c o n c e r n t h a t t h e r e must be s t a n d a r d s o f measurement o r p r o o f t h a t c o u l d s u p p o r t e n f o r c e m e n t a c t i o n s a g a i n s t a n y v i o l a t o r s of the r e g u l a t i o n s . Several p o s s i b l e c o u r s e s o f a c t i o n were a v a i l a b l e . A l t h o u g h t h e a n a l o g o u s F e d e r a l r e g u l a t i o n s f o r l i s t i n g and i d e n t i f y i n g h a z a r d o u s w a s t e s were n o t y e t i n p l a c e , a s e t o f F e d e r a l r e g u l a t i o n s h a d been p r o p o s e d by EPA i n December, 1978. I n a d d i t i o n , s e v e r a l s t a t e h a z a r d o u s w a s t e programs t h e n i n e x i s t e n c e had l i s t s o f 'hazardous w a s t e s ' i n p l a c e ( e i t h e r by r e g u l a t i o n o r i n p r a c t i c a l u s e ) a s w e l l as o t h e r means f o r c h a r a c t e r i z i n g o r i d e n t i f y i n g w a s t e s f o r c o n t r o l . We a d o p t e d as S t a t e r e g u l a t i o n s t h e w a s t e s l i s t e d s p e c i f i c a l l y o r by s o u r c e i n t h e p r o p o s e d EPA r e g u l a t i o n s . I t was c l e a r , h o w e v e r , t h a t t h e s e l i s t e d w a s t e s c o n s t i t u t e d o n l y a subset o f the wastes that s h o u l d be p u t under r e g u l a t o r y c o n t r o l . EPA had also proposed i n D e c e m b e r , 1978 a s e t o f c h a r a c t e r i s t i c s , t o g e t h e r w i t h c r i t e r i a and t e s t p r o c e d u r e s , f o r

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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i d e n t i f y i n g w a s t e s as h a z a r d o u s . These were t h e c h a r a c t e r i s t i c s o f i g n i t a b i l i t y , c o r r o s i v i t y , r e a c t i v i t y , and t o x i c i t y . This scheme o f i d e n t i f y i n g h a z a r d o u s w a s t e s b a s e d on c h a r a c t e r i s t i c s was a d o p t e d i n t h e S t a t e r e g u l a t i o n s . We had l i t t l e d i f f i c u l t y i n s p e c i f y i n g p a r a m e t e r s o f t h e s e c h a r a c t e r i s t i c s , e.g., f l a s h p o i n t o r pH, t o g e t h e r w i t h t e s t p r o c e d u r e s , f o r t h e f i r s t t h r e e characteristics. But t h e f o u r t h , t o x i c i t y , was t i e d i n t h e EPA p r o p o s e d r e g u l a t i o n s t o an e x t r a c t i o n p r o c e d u r e w h i c h was, we c o n c l u d e d , n o t s a t i s f a c t o r y f o r g e n e r a l i d e n t i f i c a t i o n of t o x i c hazardous wastes. A c o n s e r v a t i v e approach to t o x i c i t y . We d i d not f i n d a s i m p l e t e c h n i c a l a p p r o a c h t o d e f i n e t h e c h a r a c t e r i s t i c of toxicity. I n d e e d , t o x i c i t y i s n o t a s i m p l e p r o p e r t y of m a t t e r , b u t i s a v e r y comple r e l a t i o n a l propert that i relativ t the living organis combination of substance exposur an o r g a n i s m , and t h e c o n c e n t r a t i o n o f t h e s u b s t a n c e . Adverse i m p a c t s o f a t o x i c s u b s t a n c e on an o r g a n i s m may be m a n i f e s t e d i n a s h o r t p e r i o d of t i m e ( a c u t e t o x i c i t y ) , o r o v e r a l o n g e r p e r i o d ( c h r o n i c t o x i c i t y ) t h a t may i n v o l v e many d i f f e r i n g forms of a d v e r s e i m p a c t , r a n g i n g f r o m m o d i f i c a t i o n of b e h a v i o r t o mutagenic or c a r c i n o g e n i c e f f e c t s i n a f f e c t e d organisms. B e c a u s e o f t h e d i f f i c u l t y we e x p e r i e n c e d i n f i n d i n g s i m p l e p r o c e d u r e s t o t e s t f o r m u t a g e n i c o r c a r c i n o g e n i c e f f e c t s of t o x i c s u b s t a n c e s i n w a s t e s , t h e a p p r o a c h i n the L o u i s i a n a r e g u l a t i o n s h a s b e e n t o a f i r s t - l i n e c r i t e r i o n of a c u t e t o x i c i t y , b a s e d e i t h e r on t h e p r e s e n c e of c e r t a i n d e s i g n a t e d m a t e r i a l s i n a w a s t e s t r e a m , e.g., m e r c u r y , o r on t h e l i s t i n g of c o m p o n e n t s o f t h e w a s t e s t r e a m i n s t a n d a r d and w i d e l y used t o x i c s r e g i s t r i e s or r e f e r e n c e works. Thus, the d e f i n i t i o n of t h e t o x i c c h a r a c t e r i s t i c was expanded f a r beyond t h e number o f s u b s t a n c e s s p e c i f i e d by t h e EPA e x t r a c t i o n p r o c e d u r e , and became l a r g e l y b a s e d on a c o m p a r i s o n t o l i t e r a t u r e r e f e r e n c e s of t h e c o n s t i t u e n t s l i s t e d by an a n a l y s i s o f a waste stream (or o t h e r w i s e known t o be p r e s e n t ) . Because the r e f e r e n c e s o u r c e s t o be used ( e . g . , Sax, NI0SH) t e n d t o be q u i t e c o n s e r v a t i v e i n r a n k i n g r e l a t i v e t o x i c i t i e s , t h e d i s t i n c t i o n s between ' a c u t e ' and ' c h r o n i c ' t o x i c i t y t e n d t o be b l u r r e d somewhat, so t h a t a g r e a t many s u b s t a n c e s w i t h low a c u t e t o x i c i t y b u t s i g n i f i c a n t c h r o n i c t o x i c i t y are included f o r r e g u l a t o r y c o n t r o l . T h e n e x t s t e p was a r e g u l a t o r y r e q u i r e m e n t on t h o s e who g e n e r a t e d , t r e a t e d , s t o r e d , o r d i s p o s e d of w a s t e s t o send i n t o t h e S t a t e n o t i f i c a t i o n s i d e n t i f y i n g the w a s t e s c o v e r e d as h a z a r d o u s w a s t e s by t h e S t a t e r e g u l a t i o n s . This n o t i f i c a t i o n p r o c e s s t e n d e d t o p r o d u c e r a t h e r c o n s e r v a t i v e i d e n t i f i c a t i o n s of w a s t e s ; t h a t i s , n o t i f i e r s t e n d e d t o i d e n t i f y as h a z a r d o u s w a s t e s a b r o a d e r s p e c t r u m o f w a s t e s t h a n have so f a r been i d e n t i f i e d a s h a z a r d o u s by EPA. The ' u n i v e r s e ' o f h a z a r d o u s w a s t e s r e g u l a t e d i n L o u i s i a n a has been l a r g e r t h a n t h a t under

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the Federal system from the beginning. However, a s e t o f p r o c e d u r e s i s a v a i l a b l e f o r d e l i s t i n g a t t h e S t a t e l e v e l any w a s t e n o t i d e n t i f i e d a s h a z a r d o u s u n d e r t h e F e d e r a l s y s t e m , by d e m o n s t r a t i o n t h a t t h e w a s t e (a) i s n o t , on t h e b a s i s o f f u r t h e r t e c h n i c a l c o n s i d e r a t i o n s , a h a z a r d o u s w a s t e under t h e S t a t e a p p r o a c h , and (b) c a n be p r o p e r l y managed o u t s i d e t h e h a z a r d o u s waste c o n t r o l system. As a c o n d i t i o n o f i n t e r i m a u t h o r i z a t i o n under t h e F e d e r a l h a z a r d o u s w a s t e r e g u l a t i o n s , L o u i s i a n a has f r o m t i m e t o t i m e f o r m a l l y a d o p t e d s u b s e q u e n t EPA l i s t i n g s o f h a z a r d o u s w a s t e s . I t has been o u r e x p e r i e n c e t h a t t h e s e w a s t e s t r e a m s have a l r e a d y b e e n c o v e r e d and were a l r e a d y b e i n g r e g u l a t e d under t h e S t a t e system. I n t u i t i v e l y , t h e S t a t e a p p r o a c h seems a l s o t o have drawn upon t h e common s e n s e o f t h e r e g u l a t e d i n d u s t r i e s . Many n o t i f i c a t i o n s o f wast meeting the toxic c h a r a c t e r i s t i j u d g m e n t s a s t o t h e k i n d s o f p r o b l e m s t h o s e w a s t e s m i g h t cause i f n o t p r o p e r l y managed. How b i g s h o u l d t h e ' u n i v e r s e ' o f h a z a r d o u s w a s t e s b e ? I must c o n f e s s t h a t , a t a v e r y e a r l y s t a g e o f r e g u l a t i o n d r a f t i n g , we s e r i o u s l y c o n s i d e r e d t h e a l t e r n a t i v e o f s i m p l y c a l l i n g a l l i n d u s t r i a l wastes 'hazardous wastes,' because o f the d i f f i c u l t i e s o f p r o v i d i n g t e c h n i c a l d e f i n i t i o n s o f t h e t e r m , and s p e c i f y i n g a n a l y t i c a l p r o c e d u r e s . We d i d n o t t a k e t h a t approach, f o l l o w i n g f u r t h e r consideration of the intent of the authorizing legislation: the approach t o s e t t i n g standards f o r management o f h a z a r d o u s w a s t e s c a l l e d f o r more s t r i n g e n t , h e n c e , g e n e r a l l y more e x p e n s i v e p r a c t i c e s t h a n w o u l d be r e q u i r e d f o r non-hazardous wastes. To r e g u l a t e e x c e s s i v e l y w a s t e s t h a t p r e s e n t l i t t l e h a z a r d would tend toward r e g u l a t o r y ' o v e r k i l l ; ' a t t h e same t i m e , f a i l u r e t o i d e n t i f y w a s t e s r e q u i r i n g s t r i n g e n t management w o u l d be r e g u l a t o r y ' u n d e r k i l l . ' Our e x p e r i e n c e i n L o u i s i a n a i s that the 'universe' o f h a z a r d o u s w a s t e s s h o u l d be somewhat l a r g e r t h a n t h a t p r e s e n t l y d e f i n e d b y E P A , s o a s t o accommodate c e r t a i n waste streams c o v e r e d i n t h e S t a t e p r o g r a m t h a t , we b e l i e v e , do need s t r i n g e n t m a n a g e m e n t , b u t a r e n o t c u r r e n t l y addressed a t the Federal level. The w a s t e s t h e m s e l v e s d o n o t h o l d t h e answer. A f u n d a m e n t a l p o i n t i s t h a t a h a z a r d o u s w a s t e s h o u l d be r e g a r d e d as o n l y a p o t e n t i a l hazard; i f p r o p e r l y managed, i t s h o u l d n o t c a u s e any a c t u a l , s i g n i f i c a n t a d v e r s e i m p a c t t o p u b l i c h e a l t h o r the environment. T h e a c t u a l r i s k s p r e s e n t e d by a h a z a r d o u s w a s t e a r e b e s t d e f i n e d i n t h e c o n t e x t o f how i t i s h a n d l e d and managed. T h e r e f o r e , t h e k e y t o t h e d e v e l o p m e n t o f the r e g u l a t o r y s y s t e m became the s e l e c t i o n of standards f o r the

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

14

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HAZARDOUS W A S T E SITES

m a n a g e m e n t o f h a z a r d o u s w a s t e s , d e s i g n e d to m i t i g a t e the h a z a r d o u s n a t u r e of the w a s t e . T h i s p e r s p e c t i v e i s employed i n a l l c a s e - b y - c a s e d e c i s i o n s o n p e t i t i o n s f o r e x e m p t i o n f r o m the r e g u l a t o r y r e q u i r e m e n t s , including petitions for delisting. The r e q u i r e d t e c h n i c a l i n f o r m a t i o n f o r e v a l u a t i o n of s u c h p e t i t i o n s i n c l u d e s not o n l y p h y s i c a l and c h e m i c a l d a t a on the w a s t e m a t e r i a l i t s e l f , but a l s o i n f o r m a t i o n on how t h e w a s t e w o u l d be managed i f a f a v o r a b l e d e c i s i o n were made on the p e t i t i o n . S e t t i n g r e g u l a t o r y s t a n d a r d s and

criteria

S t i l l m o r e d i f f i c u l t p r o b l e m s e m e r g e a t the l e v e l of e s t a b l i s h i n g the b o u n d a r i e s of a c c e p t a b l e p r a c t i c e s f o r managing hazardous wastes. Thes problem i t technical legal and p o l i t i c a l . Some t e c h n i c a l p r o b l e m s . I m p l i c i t i n t h e i d e a of a regulatory standard o r c r i t e r i o n i s some l e v e l o f r i s k assessment and r i s k e v a l u a t i o n , more o r l e s s f o r m a l l y , and w i t h more o r l e s s s o p h i s t i c a t i o n . By ' r i s k a s s e s s m e n t ' I mean t h a t some s o r t o f c a l c u l a t i o n o r e s t i m a t e i s made, however r o u g h l y , as t o the l i k e l i h o o d of an a d v e r s e i m p a c t of a h a z a r d o u s w a s t e on human h e a l t h o r the e n v i r o n m e n t . Then ' r i s k e v a l u a t i o n ' i s s o m e s o r t o f c a l c u l a t i o n o r e s t i m a t e , however r o u g h l y , as to whether t h a t l i k e l i h o o d or r i s k of adverse impact i s a c c e p t a b l e , or not. The C o n g r e s s d i r e c t e d EPA (as the L o u i s i a n a L e g i s l a t u r e d i r e c t e d t h e D e p a r t m e n t o f N a t u r a l Resources) to promulgate r e g u l a t i o n s t h a t e s t a b l i s h minimum s t a n d a r d s and c r i t e r i a f o r acceptable m a n a g e m e n t o f h a z a r d o u s w a s t e . The r e g u l a t i o n d r a f t e r s m u s t t h e n s e e k s c i e n t i f i c and t e c h n i c a l i n f o r m a t i o n t h a t enables r i s k assessments f o r v a r i o u s a l t e r n a t i v e p r a c t i c e s i n h a z a r d o u s w a s t e h a n d l i n g and management, p a r t i c u l a r l y f o r d e v e l o p m e n t o f any d e s i g n o r o p e r a t i o n s s t a n d a r d s o r c r i t e r i a f o r hazardous waste f a c i l i t i e s . B u t a t the same t i m e the r e g u l a t i o n d r a f t e r s a r e f a c e d w i t h t h e s t i l l more d i f f i c u l t j o b of d o i n g a r i s k e v a l u a t i o n . That i s , t h e y m u s t r e c o m m e n d p u b l i c p o l i c y d e c i s i o n s as to the acceptable l e v e l s o f r i s k s f o r a v a r i e t y of h a z a r d o u s w a s t e a c t i v i t i e s , e.g., a c c e p t a b l e minimums f o r the e f f i c i e n c y of d e s t r u c t i o n o f h a z a r d o u s w a s t e s by i n c i n e r a t i o n . I n p r i n c i p l e , t h i s p r o c e s s may be n o t u n l i k e the d e c i s i o n s made by a b a n k e r a b o u t a p o t e n t i a l l o a n , o r an i n s u r a n c e u n d e r w r i t e r i n s e t t i n g t h e r a t e f o r an i n s u r a n c e p o l i c y : a r i s k a s s e s s m e n t i s made, and an a p p r o p r i a t e ' s a f e t y m a r g i n ' i s f a c t o r e d i n t o the i n t e r e s t r a t e o r t h e p o l i c y premium t o a r r i v e a t an a c c e p t a b l e l e v e l of r i s k f o r t h e i n d i v i d u a l c a s e ( b u t b a s e d on e x p e r i e n c e and p r o j e c t i o n s f o r a l a r g e number of c a s e s ) .

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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But t h e r e g u l a t i o n d r a f t e r has much l e s s ' h a r d ' i n f o r m a t i o n and experience a v a i l a b l e on w h i c h t o base a r i s k e v a l u a t i o n , e.g., of acceptable l e v e l s of emissions o r releases of a carcinogen i n t o the environment. F o r r e a s o n s t h a t w i l l become a p p a r e n t , t h e r e f o r e , there i s a tendency to f a c t o r i n l a r g e r s a f e t y margins i n t o e n v i r o n m e n t a l r e g u l a t i o n s t h a n most b a n k e r s would r e q u i r e on l o a n s . There i s a r e l a t i v e l y s h o r t h i s t o r y o f engineering d a t a g a t h e r i n g a n d a n a l y s i s f o r many waste management p r a c t i c e s . B u t t h e r e a l l i m i t i n g p r o b l e m i s t h a t o f m a k i n g e v a l u a t i o n s b a s e d on p o t e n t i a l h e a l t h i m p a c t s o f t o x i c s a t low l e v e l s . I n the end, t h e r e f o r e , r i s k e v a l u a t i o n s — t h a t i s , s t a n d a r d s and c r i t e r i a — t e n d t o be l a r g e l y b a s e d on p o l i c y c o n s i d e r a t i o n s r a t h e r t h a n on s c i e n t i f i c a n d t e c h n i c a l i n f o r m a t i o n p e r s e . T h i s s i t u a t i o n w i l l , one h o p e s , e v o l v e t o a greater role f o r s c i e n t i f i accumulation of experienc A reasonable g o a l f o r e v o l u t i o n o f the r e g u l a t o r y program over t i m e , t h e r e f o r e , s h o u l d be i m p r o v e d e f f i c i e n c y o f t h e p r o g r a m , i.e., a l l o w a n c e o f l e a s t - c o s t p r a c t i c e s that achieve the r e q u i r e m e n t s o f p r o t e c t i o n o f p u b l i c h e a l t h and t h e e n v i r o n m e n t . I t i s a p p a r e n t t h a t s c i e n c e and t e c h n o l o g y s h o u l d p l a y a l e a d r o l e f o r improving the e f f i c i e n c y of the r e g u l a t o r y program over time. T h e r e s h o u l d be c o n t i n u i n g e v a l u a t i o n o f e x p e r i e n c e g a t h e r e d i n t h e o p e r a t i o n of the r e g u l a t o r y system, together with p r o v i s i o n s f o r i n c o r p o r a t i n g new i n f o r m a t i o n f r o m r e s e a r c h and d e v e l o p m e n t e f f o r t s . Some l e g a l p r o b l e m s . The p r i n c i p l e o f e n f o r c e a b i l i t y p l a y s a l a r g e r o l e i n t h e h a z a r d o u s w a s t e r e g u l a t o r y p r o g r a m . The r e g u l a t i o n d r a f t e r , t h e r e f o r e , must p a y a g r e a t deal of a t t e n t i o n t o measurement a t t h e t h r e s h o l d of c o m p l i a n c e / n o n - c o m p l i a n c e w i t h t h e r e g u l a t i o n s , and to mechanisms t h a t w i l l h e l p b u i l d c h a i n s o f e v i d e n c e i n c a s e s o f violation. A s m i g h t b e e x p e c t e d , a great d e a l o f paperwork i n e v i t a b l y enters the r e g u l a t o r y requirements f o r these reasons. B u t t h e r e a r e a l s o t e c h n i c a l r a m i f i c a t i o n s . The c o n c e p t o f e n f o r c e a b i l i t y tends t o r e q u i r e the s e t t i n g of specific q u a n t i t a t i v e m e a s u r e s f o r d e t e r m i n a t i o n of c o m p l i a n c e , as i n evaluating groundwater monitoring well data. Among t h e t e c h n i c a l c o m p l i c a t i o n s i n r e g u l a t o r y d e v e l o p m e n t i s t h e need t o s e t l e v e l s o f q u a n t i t a t i v e measurements f o r e n f o r c e m e n t p u r p o s e s that reflect as w e l l a s p o s s i b l e t h e needs o f p r o g r a m e n f o r c e m e n t , and a r e a l s o r e a s o n a b l y a c c u r a t e and r e p r o d u c i b l e . As t h e need t o m o n i t o r f o r l o w - l e v e l t o x i c s i s v e r y g r e a t f o r a h a z a r d o u s w a s t e p r o g r a m , t h i s has become a m a j o r t e c h n i c a l a r e a of d i f f i c u l t y . The p o l i t i c a l p r o b l e m . P a r a d o x i c a l l y , the focus o f p u b l i c a t t e n t i o n o n t h e n e e d t o c o n t r o l and i m p r o v e h a z a r d o u s w a s t e m a n a g e m e n t d e c i s i o n s o f t e n makes t h o s e d e c i s i o n s s t i l l more

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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A T HAZARDOUS W A S T E

SITES

d i f f i c u l t t h a n t e c h n i c a l c o n s i d e r a t i o n s alone might i n d i c a t e . W h i l e i n m a n y c a s e s i t m i g h t be a r g u e d f r o m a s c i e n t i f i c o r engineering p e r s p e c t i v e t h a t a h a z a r d o u s w a s t e management a c t i v i t y h a s met t h e r e q u i r e m e n t s o f t h e d e f i n e d s t a n d a r d s o r c r i t e r i a , l a r g e s e c t o r s o f t h e p u b l i c may d i s a g r e e . T h i s may w e l l be t r u e even i n c a s e s where a l l p a r t i e s a g r e e as t o t h e r i s k a s s e s s m e n t , i . e . , t h e l i k e l i h o o d o f an a d v e r s e e v e n t o r impact. I n the end, a r i s k e v a l u a t i o n i s to a g r e a t e r o r l e s s e r degree a s u b j e c t i v e d e c i s i o n . Perhaps the s i n g l e g r e a t e s t task f a c i n g government i n t h e i m p l e m e n t a t i o n o f t h e h a z a r d o u s w a s t e p r o g r a m i s t h e r e d u c t i o n o f u n c e r t a i n t y and s u b j e c t i v i t y a t t h e l e v e l o f r i s k e v a l u a t i o n f o r h a z a r d o u s w a s t e management. The

Louisiana experience

on s t a n d a r d s and c r i t e r i a

A heavy e m p h a s i s i n the L o u i s i a n a hazardou regulations t h e s e p e r f o r m a n c e s t a n d a r d s a r e a number o f d e s i g n s t a n d a r d s and o p e r a t i n g r e q u i r e m e n t s d e s i g n e d t o m i n i m i z e releases or emissions of hazardous wastes. To a c o n s i d e r a b l e d e g r e e , t h e s e r e g u l a t i o n s have s a t i s f i e d t h e t e c h n i c a l and l e g a l r e q u i r e m e n t s and g o a l s o f t h e p r o g r a m . D e m o n s t r a b l y , t h e p r o g r a m has r e s u l t e d i n g r e a t improvements o f w a s t e management p r a c t i c e s i n t h e s t a t e . C e r t a i n l y , no examples o f g r o s s mismanagement o f w a s t e s , s u c h as t h o s e w h i c h r e s u l t e d i n some o f t h e abandoned s i t e s i n t h e s t a t e , a r e now o p e r a t i n g . Whether t h e L o u i s i a n a p r o g r a m has y e t s a t i s f i e d t h e p o l i t i c a l requirement, that i s , s a t i s f a c t i o n of the p u b l i c ' s e x p e c t a t i o n s , r e m a i n s i n doubt — a s i t does a t t h e F e d e r a l l e v e l and i n t h e o t h e r s t a t e s , as w e l l . Some m i s t a k e s o f t h e p a s t :

"abandoned" s i t e s

I n e a r l y 1979, we had i d e n t i f i e d some 14 p r o b l e m s i t e s i n L o u i s i a n a t h a t w e r e t h e r e s u l t o f p o o r p a s t management practices. T y p i c a l l y , these s i t e s represented grossly u n a c c e p t a b l e p a s t p r a c t i c e s , and n o t m e r e l y m i n o r d e p a r t u r e s f r o m g o o d e n g i n e e r i n g and o p e r a t i n g c o n d i t i o n s . Substantial p r o g r e s s was made i n g e t t i n g s e v e r a l o f t h e s e s i t e s c l e a n e d up by r e s p o n s i b l e p a r t i e s . However, t h e e f f e c t i v e n e s s o f s t a t e government t o compel o r encourage p r i v a t e p a r t y cleanup of o l d problem s i t e s appears to h a v e d i m i n i s h e d a t t h e same t i m e p u b l i c a t t e n t i o n has been drawn to these problem s i t e s — p e r h a p s even b e c a u s e o f that attention. An a d d i t i o n a l f a c t o r w h i c h may be r e s p o n s i b l e f o r slowdown i n t h e r a t e o f s i t e c l e a n u p s seems t o be t h e p a s s a g e and s u b s e q u e n t s l o w r a t e o f i m p l e m e n t a t i o n o f S u p e r f u n d . L a s t y e a r , t h e S t a t e p r o p o s e d c l e a n u p o f an abandoned s i t e , f o l l o w i n g a f e a s i b i l i t y i n v e s t i g a t i o n of the s i t e that i n d i c a t e d t h a t o n - s i t e d i s p o s a l o f t h e w a s t e s w o u l d be e n v i r o n m e n t a l l y

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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a c c e p t a b l e , a s w e l l as t h e most c o s t - e f f e c t i v e a p p r o a c h . Strong p u b l i c r e a c t i o n t o t h e c l e a n u p p l a n emerged, and no a c t i o n h a s y e t been t a k e n . A s i d e f r o m o t h e r t e c h n i c a l p r o b l e m s and h i g h e r c o s t s t h a t w o u l d be associated with o f f - s i t e disposal of the w a s t e s f r o m t h i s s i t e , a n o t h e r p a t t e r n i s now v i s i b l e and p r e d i c t a b l e ; i f d i s p o s a l o f these m a t e r i a l s i s proposed a t any s u i t a b l e commercial f a c i l i t y , t h i s w i l l arouse o p p o s i t i o n i n the l o c a l area of the r e c i p i e n t f a c i l i t y . I t s e e m s u n l i k e l y t h a t t h e p u b l i c w i l l n o t demand and encourage p o s i t i v e approaches t o cleanup. R a t h e r , the d i f f i c u l t y o f b u i l d i n g a c o n s e n s u s f o r proposed actions i l l u s t r a t e s the complexity o f t h e s o c i a l and p o l i t i c a l i s s u e s that a l s o play a part i n governmental a c t i o n s . I suspect — a n d hope — t h a t t h e s l o w d o w n i s only temporary. I t appear those already discussed p r i v a t e p a r t i e s a b o u t p o t e n t i a l l i a b i l i t y following cleanup, r a i s e d by t h e p a s s a g e o f t h e C o m p r e h e n s i v e Emergency R e s p o n s e , Compensation and L i a b i l i t y A c t ( C E R C L A , a l s o known as Superfund). The q u e s t i o n as t o "how c l e a n i s c l e a n " has become a question with not only t e c h n i c a l but l e g a l r a m i f i c a t i o n s since t h e p a s s a g e o f CERCLA. As w i t h t h e h a z a r d o u s w a s t e r e g u l a t o r y p r o g r a m , a c o m b i n a t i o n o f t e c h n i c a l , l e g a l and p o l i c y answers may b e r e q u i r e d t o e x p e d i t e r e s o l u t i o n of e x i s t i n g o l d s i t e problems. The S t a t e h a s l i s t e d s e v e n s i t e s i n t h e s t a t e f o r p o s s i b l e S u p e r f u n d a c t i o n . A t o n e , s e v e r a l t h o u s a n d drums o f w a s t e were s t a c k e d above g r o u n d , a n d t h e n abandoned. A n o t h e r r e p r e s e n t s a c a s e o f good i n t e n t i o n s gone b a d ; a c o m m e r c i a l w a s t e s i t e t h a t lacked tight regulatory controls t o set i t s operating c o n d i t i o n s , and c o n s e q u e n t l y g o t i n t o t r o u b l e . A n o t h e r s t a r t e d o u t a s a m u n i c i p a l s o l i d w a s t e s i t e , and somehow ended up a s an u n c o n t r o l l e d dump f o r h a z a r d o u s w a s t e s . S t i l l a n o t h e r was a n o l d w a s t e o i l r e c o v e r y p l a n t t h a t was o p e r a t e d v e r y p o o r l y , i n a poor s i t e area. The 'Mitre Model' and s i t e ranking. EPA has d e v e l o p e d a h a z a r d a s s e s s m e n t m o d e l (commonly c a l l e d t h e M i t r e M o d e l ) t o h e l p rank problem hazardous waste s i t e s f o r p o t e n t i a l Superfund response. The model i s a r e l a t i v e l y s i m p l e o n e , w i t h m i n i m a l data requirements. The model i s d e s i g n e d t o p r o v i d e s c o r e s f o r a c t u a l o r p o t e n t i a l i m p a c t s on h e a l t h o r t h e e n v i r o n m e n t by three routes o f exposure — groundwater, surface water, o r a i r e m i s s i o n s — a s w e l l as b y d i r e c t c o n t a c t o r f i r e and e x p l o s i o n . P a r a m e t e r s i n c l u d e t o x i c i t y , q u a n t i t y , p h y s i c a l s t a t e and p e r s i s t e n c e o f t h e w a s t e a t a s i t e ; c h a r a c t e r i s t i c s of a p o t e n t i a l route ( t o g r o u n d w a t e r , surface water, o r a i r ) of r e l e a s e o f t h e w a s t e s , e . g . , s o i l p e r m e a b i l i t y ; t h e mode o f e x p o s u r e o r u s e o f t h e n a t u r a l r e s o u r c e , e . g . , an a q u i f e r o r s u r f a c e w a t e r s u s e d f o r d r i n k i n g w a t e r ; and t h e t a r g e t o f

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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e x p o s u r e , e.g., p o p u l a t i o n u s i n g the a q u i f e r w i t h i n a s p e c i f i e d r a d i u s of the s i t e . The L o u i s i a n a s i t e s so f a r r a n k e d u s i n g d r a f t g u i d a n c e f o r d a t a i n p u t t o t h e model have n o t s c o r e d h i g h , compared t o many other s i t e s i n the n a t i o n . I n g e n e r a l , two f a c t o r s a c c o u n t f o r the r e l a t i v e l y low s c o r e s : (1) l o w p o p u l a t i o n d e n s i t y ( e x c e p t i n o n e c a s e ) ; a n d (2) s u b s u r f a c e g e o l o g y and h y d r o l o g y t h a t tends to minimize p o t e n t i a l f o r groundwater c o n t a m i n a t i o n . Our e x p e r i e n c e has l e d us t o doubt t h e u t i l i t y o f t h e M i t r e M o d e l f o r s i t e r a n k i n g , b e y o n d i t s u s e as a ' f i r s t c u t ' screening device. The model s c o r e s f o r t h e L o u i s i a n a s i t e s do n o t a p p e a r t o c o r r e l a t e p a r t i c u l a r l y w e l l w i t h o t h e r means o f e v a l u a t i n g t h e r e l a t i v e r a n k i n g o f p r o b l e m s e r i o u s n e s s , n o r do t h e y g i v e a n y u s e f u l i n s i g h t a s t o t h e type o r extent of r e s p o n s e t h a t may be r e q u i r e d . In discussions wit does n o t a p p e a r t o p r o v i d t h e r e l a t i v e l e v e l s o f r i s k s posed by d i f f e r e n t s i t e s , n o r does i t p r o v i d e a b a s i s f o r management d e c i s i o n s once a r a n k e d l i s t has been g a t h e r e d . On t h e o t h e r h a n d , i t i s c l e a r — again b a s e d on o u r e x p e r i e n c e — t h a t t h e model w o u l d be t o o e x p e n s i v e t o use as a s c r e e n i n g d e v i c e a t any l e v e l , i f i t were made much more s o p h i s t i c a t e d t h a n i t i s now. F o r e x a m p l e , t h e c o l l e c t i o n and a n a l y s i s o f d a t a on t h e ' g r o u n d w a t e r r o u t e ' c a n c o s t more t h a n $100,000. L o u i s i a n a has done r a t h e r extensive s i t e i n v e s t i g a t i o n s f o r most o f t h e s i t e s l i s t e d w i t h EPA, and t h e investments o f r e s o u r c e s have been s u b s t a n t i a l . We b e l i e v e t h a t , because o f t h e s i m p l i c i t y o f t h e M i t r e Model, t h i s poses p r o b l e m s o f c o m p a r a b i l i t y w i t h o t h e r r a n k e d s i t e s , where much l e s s i n f o r m a t i o n may have been a v a i l a b l e . Among t h e more s e r i o u s p r o b l e m s i n a s s e s s i n g an o l d s i t e i s t h e d i f f i c u l t y and expense o f c h a r a c t e r i z i n g t h e w a s t e s . From a t e c h n i c a l p o i n t o f v i e w , i t r a r e l y makes s e n s e t o t a l k about a ' r e p r e s e n t a t i v e ' s a m p l e , p a r t i c u l a r l y i f t h o u s a n d s o f drums o f w a s t e s f r o m mixed s o u r c e s a r e p r e s e n t . RCRA and CERCLA p r e s e n t d i f f e r e n t t e c h n i c a l p r o b l e m s . At f i r s t g l a n c e , t h e t e c h n i c a l n e e d s f o r a h a z a r d o u s waste r e g u l a t o r y p r o g r a m , and f o r r e s p o n s e t o o l d p r o b l e m s i t e s m i g h t seem n e a r l y i d e n t i c a l . Our e x p e r i e n c e i n d i c a t e s t h a t t h i s i s n o t s o . The p r o t o c o l s f o r s a m p l i n g and a n a l y s i s a t an o p e r a t i n g s i t e c a n b e w e l l s p e c i f i e d b e c a u s e t h e t y p e s and s o u r c e s o f w a s t e s a r e known, t h e management t e c h n i q u e s and o p e r a t i o n s a r e s p e c i f i e d , a n d t h e r e g u l a t e d f a c i l i t y i s r e q u i r e d to develop e x t e n s i v e r e c o r d s a n d a n o p e r a t i n g l o g . The o b j e c t i v e o f sampling a n d w a s t e a n a l y s i s p l a n s a t an o p e r a t i n g s i t e i s , s i m p l y , q u a l i t y c o n t r o l on r i g i d l y s p e c i f i e d and w e l l documented operations. Q u i t e d i f f e r e n t s t r a t e g i e s f o r s a m p l i n g and a n a l y s i s a r e r e q u i r e d a t a n o l d p r o b l e m s i t e . I n t h i s c a s e , l i t t l e o r no

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

2.

DE VILLE

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documentation o f the o p e r a t i o n s a t the site — including c h e m i c a l a n a l y s e s o f t h e w a s t e s , management o f t h e w a s t e s , and d e t a i l s and l o c a t i o n o f d i s p o s a l areas — i s a v a i l a b l e . With r e l a t i v e l y l i m i t e d r e s o u r c e s , t h e r e s p o n d i n g g o v e r n m e n t a l agency m u s t t a r g e t i t s s a m p l i n g a n d a n a l y s i s e f f o r t s t o meet t h e o b j e c t i v e s o f p r o b l e m d e f i n i t i o n ( t h e hazardous m a t e r i a l s p r e s e n t , t h e e x t e n t and n a t u r e o f c o n t a m i n a t i o n o f t h e s i t e , and t h e s u r f a c e a n d s u b s u r f a c e c h a r a c t e r i s t i c s o f t h e s i t e ) ; and d e v e l o p m e n t o f a f e a s i b l e s t r a t e g y to address the problems ( i n c l u d i n g , f o r e x a m p l e , an a s s e s s m e n t o f t h e s u i t a b l i l t y o f t h e s i t e f o r o n - s i t e b u r i a l o f p a r t o r a l l o f the waste m a t e r i a l s ) . I n e v i t a b l y , t h e a v a i l a b l e d a t a w i l l be l i m i t e d by c o n t r a s t t o t h e d a t a t h a t s h o u l d now be a v a i l a b l e f r o m a p r o p e r l y o p e r a t e d h a z a r d o u s w a s t e m a n a g e m e n t f a c i l i t y t h a t i s s u b j e c t t o the current Louisiana or t h e abandoned s i t e i s t h e c o s t o f r e c o n t a i n e r i z a t i o n o r immediate d i s p o s a l o f the w a s t e s , a n d a n a v e r a g e a n a l y t i c a l c o s t t h a t may r a n g e w e l l upwards o f $500 p e r drum s a m p l e d . G i v e n a s i t e , f o r example, w h e r e c o n t a i n e r s h a v e a l r e a d y d e t e r i o r a t e d , the concerns f o r a n a l y s i s w i l l p r o b a b l y n o t c e n t e r on w h e t h e r t h e w a s t e s a r e i n c o m p a t i b l e ( t h e y h a v e a l r e a d y r e a c t e d , i f s o ) , b u t on t h e t e c h n i c a l f e a s i b i l i t y o f o n - s i t e v e r s u s o f f - s i t e ( o r some combination) d i s p o s a l o f the wastes p r e s e n t . D e g r e e o f h a z a r d and l e v e l o f c o n t r o l One o f t h e most promising t e c h n i c a l approaches t o r e g u l a t i o n o f h a z a r d o u s w a s t e s (and one t h a t a l r e a d y seems i n p r o g r e s s f o r e v a l u a t i o n and r e s p o n s e t o o l d p r o b l e m s i t e s ) i s t h e d e v e l o p m e n t o f a ' d e g r e e o f h a z a r d ' s y s t e m of waste classification. The c u r r e n t RCRA a p p r o a c h a n d , t o a s l i g h t l y l e s s e r d e g r e e , the L o u i s i a n a a p p r o a c h tend t o treat a l l hazardous wastes as about e q u a l . I n f a c t , however, i t i s a p p a r e n t t h a t w a s t e m a t e r i a l s d i f f e r v e r y g r e a t l y over a s p e c t r u m o f i n t e n s i t y o f t h e c h a r a c t e r i s t i c s t h a t make them hazardous. T h i s i s p a r t i c u l a r l y so f o r the c h a r a c t e r i s t i c o f toxicity. The d e g r e e o f h a z a r d a p p r o a c h , on t h e f a c e o f i t , may o f f e r a s i m i l a r b a s i s f o r p r e s c r i b i n g a s o r t o f i n t e n s i t y o f need f o r management. Beyond t h i s , i t i s a l s o a p p a r e n t t h a t , g i v e n t h e c h o i c e o f a v a i l a b l e management o p t i o n s f o r a g i v e n w a s t e s t r e a m ( s u c h a s l a n d t r e a t m e n t , land b u r i a l , i n c i n e r a t i o n , chemical f i x a t i o n , e t c . ) t h e r e c a n be t e c h n i c a l d e c i s i o n s r e n d e r e d as t o w h i c h o f t h e s e o p t i o n s a r e s u i t a b l e f o r the waste m a t e r i a l ( e . g . , a c h l o r i n a t e d h y d r o c a r b o n s o l v e n t w a s t e ) , and w h i c h a r e l e s s s u i t a b l e , o r even u n a c c e p t a b l e . The t e c h n i c a l c h a l l e n g e s t o t h e d e v e l o p m e n t o f a h a z a r d o u s w a s t e management scheme b a s e d on s u c h p r e m i s e s a r e g r e a t . F o r e x a m p l e , s t a n d a r d m e t h o d o l o g i e s f o r e v a l u a t i n g the p r o b a b l e

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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performance o f t e c h n i c a l o p t i o n s f o r treatment o r d i s p o s a l of a w a s t e m a t e r i a l , and i m p r o v e d and s i m p l i f i e d m e t h o d o l o g i e s f o r r i s k a s s e s s m e n t , need t o be d e v e l o p e d . B u t t h e p o t e n t i a l u s e f u l n e s s o f s i m p l i f i e d management t o o l s t o c h o o s e t h e o p t i m a l l e v e l o f c o n t r o l and t e c h n o l o g y f o r h a n d l i n g h a z a r d o u s w a s t e s may w e l l be a d r i v i n g f o r c e t o f u t u r e d e s i g n s , not o n l y of hazardous waste treatment f a c i l i t i e s , but a l s o of the r e g u l a t o r y system i t s e l f . R E C E I V E D July 7,

1982.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

3 Determining the Impacts on Human Health Attributable to Hazardous Waste Sites VERNON N. HOUK Center for Environmental Health, Centers for Disease Control, Atlanta, GA 30333

The Superfund Act and implementing E x e c u t i v e Order assign to the Departmen the responsibility waste s i t e s pose to the h e a l t h of workers and the general p u b l i c . Our working definition for such a h e a l t h risk assessment i s the determination of probabilities of v a r i o u s adverse h e a l t h outcomes that r e s u l t or would r e s u l t from exposure to s p e c i f i e d hazards. To fulfill our l e g a l mandate, we intend first to determine the nature and q u a n t i t y of t o x i c m a t e r i a l s present at Superfund sites, the s i z e and p r o x i m i t y of potentially exposed human p o p u l a t i o n s , and the existence of likely pathways for s i g n i f i c a n t human exposure. I f all three f a c t o r s are present, a d d i t i o n a l study through v a r i o u s approaches, such as exposure documentation s t u d i e s , d i s e a s e - r e l a t e d epidemiologic s t u d i e s , or disease registries, will be considered.

I n December 1980, P r e s i d e n t C a r t e r s i g n e d i n t o l a w a b i l l known as t h e C o m p r e h e n s i v e E n v i r o n m e n t a l R e s p o n s e , Compensation and L i a b i l i t y A c t — m o r e commonly known as t h e S u p e r f u n d A c t . I t i s d e s i g n e d t o d e a l w i t h t h e b u r g e o n i n g p r o b l e m o f c l e a n i n g up o l d and abandoned h a z a r d o u s w a s t e s i t e s . The A c t imposes a t a x on t h e c h e m i c a l i n d u s t r y and t h e n a l l o c a t e s t h a t money, a l o n g w i t h a F e d e r a l and S t a t e c o n t r i b u t i o n , t o s i t e s n e e d i n g emergency r e s p o n s e o r l o n g - t e r m c l e a n u p ; a s s e s s m e n t o f h e a l t h e f f e c t s w h i c h may r e s u l t f r o m e x p o s u r e ; and e n f o r c e m e n t a c t i o n against p a r t i e s r e s p o n s i b l e f o r these s i t e s , i n c l u d i n g generat o r s , t r a n s p o r t e r s , and s i t e owners. O f f i c i a l s o f the E n v i r o n m e n t a l P r o t e c t i o n Agency (EPA) t e s t i f i e d b e f o r e C o n g r e s s t h a t EPA h a d i d e n t i f i e d o v e r 9,600 u n c o n t r o l l e d h a z a r d o u s w a s t e s i t e s , h a d made p r e l i m i n a r y a s s e s s m e n t s o f 6,100 o f t h e s e , and, b y J u l y 1981, h a d c o m p l e t e d 0097-615 6/82/0204-0021 $06.00/0 © 1982 American Chemical Society

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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a l m o s t 2,800 o n - s i t e i n s p e c t i o n s , i n c l u d i n g some s a m p l i n g o f s i t e c o n t e n t s and g r o u n d and s u r f a c e w a t e r . The C e n t e r s f o r D i s e a s e C o n t r o l (CDC), an agency o f t h e P u b l i c H e a l t h S e r v i c e , h a s been a s s i g n e d t h e r e s p o n s i b i l i t y f o r implementing the h e a l t h - r e l a t e d portions of Superfund f o r the D e p a r t m e n t o f H e a l t h and Human S e r v i c e s . A l t h o u g h CDC h a s t h e p r i n c i p a l r o l e i n m e a s u r i n g t h e i m p a c t o r p o t e n t i a l i m p a c t on human h e a l t h w h i c h may be r e l a t e d t o e x p o s u r e , t h e N a t i o n a l T o x i c o l o g y P r o g r a m and t h e N a t i o n a l L i b r a r y o f M e d i c i n e h a v e a c t i v e r o l e s i n p r o v i d i n g u p - t o - t h e - m i n u t e i n f o r m a t i o n about t h e known h e a l t h e f f e c t s o f c h e m i c a l s o r c h e m i c a l c o m b i n a t i o n s f o u n d i n Superfund s i t e s . S i m i l a r l y , CDC s N a t i o n a l I n s t i t u t e f o r O c c u p a t i o n a l S a f e t y and H e a l t h w i l l h e l p e n s u r e t h a t t h e h e a l t h o f emergency p e r s o n n e l and c l e a n u p w o r k e r s i s p r o t e c t e d when they respond i n Superfund a c t i o n s The tremendous numbe c o u n t r y r e f l e c t s t h e growt syntheti organi i n d u s t r y ( F i g u r e 1 ) . I n 1940, a p p r o x i m a t e l y one b i l l i o n pounds o f s y n t h e t i c o r g a n i c c h e m i c a l s were p r o d u c e d i n t h e U n i t e d States. By 1965, t h i s q u a n t i t y had i n c r e a s e d n e a r l y a h u n d r e d f o l d and i t now e x c e e d s 300 b i l l i o n pounds a y e a r . T h i s e x p o n e n t i a l growth o f the i n d u s t r y has a worrisome byp r o d u c t i n t h e m a s s i v e p r o b l e m o f t o x i c w a s t e d i s p o s a l . To d e t e r m i n e i f s u c h w a s t e s c a u s e h e a l t h damage i n e x p o s e d human p o p u l a t i o n s , we must c o n d u c t e p i d e m i o l o g i c i n v e s t i g a t i o n s o f r e l a t i o n s h i p s b e t w e e n t o x i c e x p o s u r e and p o s s i b l e a d v e r s e h e a l t h outcome, c l i n i c a l o r s u b c l i n i c a l . I n c o n d u c t i n g human h e a l t h s t u d i e s b e f o r e S u p e r f u n d was e n a c t e d , we f o u n d t h a t s u c h i n v e s t i g a t i o n s a r e c o n c e p t u a l l y s i m p l e and i n v o l v e s t r a i g h t f o r w a r d c o n c e p t s o f c a u s e and e f f e c t . I m p l e m e n t i n g t h e s e s t u d i e s , however, i s " e a s i e r s a i d t h a n done." Because o f the e x t r e m e l y d i v e r s e s i t u a t i o n s i n which hazardous m a t e r i a l s a r e i n v o l v e d , each study presents unique problems. Table I i l l u s t r a t e s the d i v e r s i t y , both i n waste m a t e r i a l s and e x p o s u r e s e t t i n g s , o f e i g h t r e c e n t t o x i c w a s t e situations. D i f f e r e n c e s , i n f a c t , c a n be q u i t e l a r g e , r a n g i n g f r o m t h e common d r u m - f i l l e d dump s i t e t o t h e w i d e s p r e a d d i s p e r s a l o f waste m a t e r i a l . Some g e n e r a l i z a t i o n s , however, c a n be made about t h e s e k i n d s o f s t u d i e s . E p i d e m i o l o g i c s t u d i e s u s u a l l y c o n s i s t o f three fundamental phases: ( 1 ) D e t e r m i n i n g what t o x i c m a t e r i a l s a r e p r e s e n t , (2) e s t a b l i s h i n g how human e x p o s u r e t o t h e s e t o x i c m a t e r i a l s m i g h t o c c u r , and ( 3 ) m e a s u r i n g a c t u a l o r p o t e n t i a l b i o l o g i c effects. S u b s t a n t i v e i n f o r m a t i o n i n e a c h o f t h e s e phases i s e s s e n t i a l f o r s u c c e s s f u l l y c o m p l e t i n g any e p i d e m i o l o g i c s t u d y . The f i r s t s t e p i n any t o x i c w a s t e s t u d y i s t o d e t e r m i n e what t o x i c m a t e r i a l s a r e p r e s e n t and i n what amounts. Since most t o x i c w a s t e s i t u a t i o n s i n v o l v e t h e dumping o f d i v e r s e m a t e r i a l s , p r o b l e m s o f e x p e n s i v e t e c h n i c a l m e t h o d o l o g y c a n be formidable. However, w i t h o u t an a d e q u a t e i n v e n t o r y o f t h e 1

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

Ηουκ

Impacts on Human Health

1915

1925

1935

1945 Year

1955

1965

1975

Figure 1. Historical growth of the synthetic organic chemical industry. (Repro­ duced from Ref. 15.)

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

24

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A T HAZARDOUS W A S T E

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TABLE I R e c e n t S i t u a t i o n s I n v o l v i n g P o t e n t i a l Human Exposure t o P o t e n t i a l l y T o x i c Waste M a t e r i a l s Principal Routes of Potential Human E x p o s u r e

Location of S i t e

Toxic Materials

Physical Condition

L o v e C a n a l dump Niagara F a l l s , New Y o r k

Largely hydro­ carbon residues from p e s t i c i d e production

I n a c t i v e landf i l l i n resi­ d e n t i a l area

Direct, air­ b o r n e , and waterborne contacts

M e l v i n Wade dump, C h e s t e r , Pennsylvania

Diverse organic chemical

Surface c o l ­ lectio wast

Direct contact, explosion d g

Woburn, Massachusetts

A r s e n i c com­ pounds , h e a v y metals, organic chemicals

Abandoned waste lagoon with multiple s u r f a c e dumps

D i r e c t and waterborne contacts

Triana, Alabama

DDT and r e l a t e d compounds

Industrial w a s t e dumped in a rural stream

Food c h a i n (fish)

Βloomington, Indiana

Polychlorinated biphenyls (PCB s)

Direct contact Industrial waste contamiand p o s s i b l y nating municifood c h a i n p a l sewage u s e d f o r garden manure

T r i s t a t e Mining District, Oklahoma, K a n s a s , and Missouri

Heavy m e t a l s , acidic aquifer

Mine t a i l i n g s and a c i d i c aquifer recharge

Montgomery County, Pennsylvania

Trichlorethylene

Industrial D i r e c t and waste contamiwaterborne nating aquifer; contacts underground s t o r a g e tank rupture

Pittston, Pennsylvania

Chlorinated s o l v e n t s , HCN, and h e a v y metals

M i l l i o n s of g a l l o n s of w a s t e dumped i n t o abandoned mine s h a f t s

f

A i r b o r n e and irreparably contaminated aquifer

Food c h a i n and waterborne exposure

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

3.

HOUR

Impacts on

Human Health

25

c h e m i c a l s — t h e i r q u a l i t y and q u a n t i t y and t h e p h y s i c a l c o n d i t i o n s under which they are p r e s e n t — i t i s premature, i f not i m p o s s i b l e , t o d e s i g n adequate e p i d e m i o l o g i c s t u d i e s . I f o n l y low c o n c e n t r a t i o n s o r s m a l l amounts o f t o x i n s a r e p r e s e n t , t h e r e may not be s u f f i c i e n t r e a s o n t o p r o c e e d w i t h i n v e s t i g a t i o n s . The d e c i s i o n o f w h e t h e r t o p r o c e e d i s not a l w a y s s i m p l e , s i n c e p u b l i c c o n c e r n and p o l i t i c a l p r e s s u r e can be c o m p e l l i n g e v e n i n the absence o f a c o n f i r m e d t o x i c exposure. D e s p i t e such p r e s s u r e s , i t i s important to r e a l i z e t h a t c o n d u c t i n g even a simple survey o f h e a l t h e f f e c t s i s p e r i l o u s i f one l a c k s i n f o r m a t i o n about t o x i n s and e x p o s u r e , s i n c e few, i f any, m e a s u r a b l e h e a l t h e f f e c t s a r e s u f f i c i e n t l y s p e c i f i c f o r e x p o s u r e t o p a r t i c u l a r t o x i n s o r g r o u p s o f t o x i n s t o be s u r r o gates f o r d i r e c t l y measuring t o x i c exposure. A f t e r a s s e s s i n g th n a t u r d quantitie f toxin present one must e v a l u a t e t h e i m a t e r i a l s known t o be t o x i present exposur y h a v e o c c u r r e d o r may be o n l y r e m o t e l y p o s s i b l e . B e f o r e e x p o s u r e c a n be e v a l u a t e d , t h e means o f e x p o s u r e ( f o r e x a m p l e , d i r e c t c o n t a c t , c o n t a m i n a t e d w a t e r , o r c o n t a m i n a t e d a i r ) must be d e t e r m i n e d , and the s i z e o f human p o p u l a t i o n s p o t e n t i a l l y e x p o s e d and t h e i r d e g r e e o f p r o x i m i t y t o t h e t o x i c m a t e r i a l s must be defined. A n o t h e r r e a s o n one must c o n s i d e r the n a t u r e o f t h e c h e m i c a l s i n v o l v e d i s t h a t some c h e m i c a l s p a s s t h r o u g h t h e body q u i c k l y , whereas o t h e r s are s t o r e d i n t i s s u e . Exposure to c h e m i c a l s w h i c h p e r s i s t i n t i s s u e , s u c h as P o l y c h l o r i n a t e d B i p h e n y l s ( P C B ' s ) o r DDT, o f c o u r s e , p r o v i d e s much g r e a t e r o p p o r t u n i t y f o r p r o d u c t i v e epidemiologic study than exposure to t r a n s i e n t a g e n t s ( s u c h as t r i c h l o r o e t h y l e n e i n Montgomery C o u n t y ) . Many s t u d i e s a r e u n d e r t a k e n l o n g a f t e r a c t i v e e x p o s u r e has occurred. I n s u c h s t u d i e s , e x p o s u r e can be j u d g e d o b j e c t i v e l y by m e a s u r i n g l e v e l s of p e r s i s t e n t t o x i n s i n t i s s u e . The p r i m e o b j e c t i v e i n e p i d e m i o l o g i c s t u d i e s i s t o a s s o c i a t e p a r t i c u l a r e x p o s u r e s w i t h p o t e n t i a l h e a l t h e f f e c t s and t h u s t o d e f i n e c a u s e - e f f e c t r e l a t i o n s h i p s . S i n c e t h i s p r o c e s s i s an i n d i r e c t a s s e s s m e n t , i t i s h i g h l y d e p e n d e n t on t h e a c c u r a c y and s p e c i f i c i t y o f o b s e r v a t i o n s r e c o r d e d b o t h f o r e x p o s u r e and outcome. I t i s a more p o w e r f u l s t u d y i f d o s e - r e s p o n s e r e l a t i o n s h i p s c a n be shown, t h a t i s , i f i n c r e a s i n g l e v e l s o f e x p o s u r e are a s s o c i a t e d w i t h i n c r e a s i n g f r e q u e n c y of the h e a l t h e f f e c t s in individuals. To d e t e r m i n e t h i s c a u s e - e f f e c t r e l a t i o n s h i p , t h e e p i d e m i o l o g i s t must be aware o f f o u r d i f f i c u l t i e s w h i c h can l i m i t t h e power o f an e p i d e m i o l o g i c i n v e s t i g a t i o n ( T a b l e I I ) . The f i r s t i n v o l v e s t h e s i z e o f t h e p o p u l a t i o n needed f o r a s t u d y t o demons t r a t e a g i v e n h e a l t h e f f e c t w i t h a g i v e n d e g r e e o f power. This depends b o t h on t h e d e g r e e o f e x p o s u r e and on t h e e x p e c t e d b a s e l i n e frequency o f the p a r t i c u l a r h e a l t h e f f e c t . I f the

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

RISK ASSESSMENT A T HAZARDOUS W A S T E SITES

TABLE I I Epidemiologic Evaluating Potentia Epidemiologic

Issues

Issues

Fundamental t o

Impact on E p i d e m i o l o g i c

Study

Expected b a s e l i n e frequency of s p e c i f i c h e a l t h e f f e c t s

R e l a t i v e l y low expected f r e quency r e q u i r e s l a r g e p o p u l a t i o n f o r study, e s p e c i a l l y to detect small increases i n risk.

Latency

Long l a t e n c y may r e q u i r e p e r i odic or continuous long-term population followup.

period

Multiple causative factors (clinical nonspecificity)

Since p a r t i c u l a r health e f f e c t s are not o f t e n s p e c i f i c f o r p a r t i c u l a r t o x i c exposures, d a t a must b e c o l l e c t e d and evaluated.

A l t e r a t i o n of r o u t i n e l y c o l l e c t e d exposure and/or outcome i n f o r m a t i o n t o coincide

D i m i n i s h e s p r e c i s i o n o f exposure/outcome r e l a t i o n s h i p .

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

3.

HOUK

Impacts on

Human Health

27

h e a l t h outcome t o be measured i s r a r e , t h e p o p u l a t i o n t o be s t u d i e d needs t o be l a r g e . The s e c o n d d i f f i c u l t y i s t h a t o f l o n g o r v a r i a b l e l a t e n c y , t h e p e r i o d b e t w e e n e x p o s u r e and m e a s u r a b l e e f f e c t . At lower l e v e l s o f t o x i c e x p o s u r e , outcomes s u c h as c a n c e r may not o c c u r u n t i l years l a t e r . T h i s means t h a t t h e s t u d y d e s i g n must i n c l u d e long-term h e a l t h followup. The u s u a l r e c o m m e n d a t i o n i s t o e s t a b l i s h an e x p o s u r e r e g i s t r y , w i t h a 20- t o 2 5 - y e a r s t u d y . The a l t e r n a t i v e i s t o s t u d y c u r r e n t c a n c e r i n a p o p u l a t i o n known t o have been e x p o s e d o v e r a span o f y e a r s . Neither alternative i s e a s y s i n c e r e g i s t r i e s a r e e x p e n s i v e and c o m p l i c a t e d l o g i s t i c a l l y by t h e m o b i l i t y o f t h e U.S. population. The t h i r d d i f f i c u l t y i s t h a t o f c o m p e t i n g c a u s e s o r , expressed d i f f e r e n t l y , the c l i n i c a l n o n s p e c i f i c i t y o f the h e a l t h e f f e c t s under study. T f o r many p o t e n t i a l c o n f o u n d i n d e s i g n must i n c l u d e c o l l e c t i n g exposure might a l s o cause the h e a l t h e f f e c t . I n p r a c t i c a l terms, t h i s means c o l l e c t i n g d a t a on p a s t o c c u p a t i o n a l e x p o s u r e s , p e r s o n a l e x p o s u r e s , s u c h as c i g a r e t t e s m o k i n g o r t h e use o f a l c o h o l o r d r u g s , and p e r s o n a l c h a r a c t e r i s t i c s , s u c h as s e x , r a c e , age, and s o c i o e c o n o m i c s t a t u s , w h i c h may p r e d i c t l e v e l s o f r i s k f o r s p e c i f i c d i s e a s e s t a t e s . The more v a r i a b l e s a s t u d y addresses, o f c o u r s e , t h e more c o m p l e x i t s e v e n t u a l a n a l y s i s and the g r e a t e r t h e s i z e o f the p o p u l a t i o n needed f o r a d e q u a t e l y assessing health effects. The f o u r t h d i f f i c u l t y — o n e o f t e n e n c o u n t e r e d — i s t h a t a h e a l t h outcome r o u t i n e l y m e a s u r e d by p o l i t i c a l b o u n d a r i e s ( c a n c e r m o r t a l i t y , f o r i n s t a n c e ) has t o be r e s h a p e d t o e n v i r o n m e n t a l b o u n d a r i e s , s u c h as t h o s e imposed by an a q u i f e r o r w i n d p a t t e r n , to i n c l u d e the p o p u l a t i o n under study. U n l e s s the e x p o s u r e o r outcome b o r d e r s a r e d e f i n e d by p r o p e r l y e x t r a p o l a t i n g o r i n t e r p o l a t i n g them t o c o i n c i d e g e o g r a p h i c a l l y , any cause-and-effeet relationship i s useless. S e v e r a l methods the e p i d e m i o l o g i s t has f o r i n v e s t i g a t i n g r e l a t i o n s h i p s v a r y g r e a t l y i n c o s t , t i m e and e n e r g y expended, and a n a l y t i c and i n t e r p r e t i v e v a l u e . The d e s c r i p t i v e s t u d y i s s i m p l y , as t h e name i m p l i e s , a s e r i e s o f r a t e s , r a t i o s , and p r o p o r t i o n s which h e l p d e s c r i b e e i t h e r the exposure or the outcome i n d e t a i l . The c a s e - c o n t r o l s t u d y i s r e l a t i v e l y e a s y t o c a r r y o u t , and new a n a l y t i c t e c h n i q u e s have a l r e a d y i n c r e a s e d i t s interpretive value. An e x p o s u r e s t u d y , a l t h o u g h not s t r i c t l y i n the r e a l m o f e p i d e m i o l o g y , documents e x p o s u r e i n v a r i o u s substrata of a population. The f o l l o w i n g t h r e e a c c o u n t s o f w a s t e - s i t e i n v e s t i g a t i o n s demonstrate f o u r major approaches to a s s e s s i n g h e a l t h e f f e c t s at hazardous waste s i t e s : (1) D e s c r i p t i v e s t u d i e s , ( 2 ) c a s e - c o n t r o l s t u d i e s , ( 3 ) s t u d i e s , and (4) c o h o r t s t u d i e s .

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

28

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Woburn, M a s s a c h u s e t t s Control Studies

SITES

- A n E x a m p l e o f D e s c r i p t i v e and C a s e -

D u r i n g t h e summer o f 1979, r e s i d e n t s i n t h i s e a s t e r n M a s s a c h u s e t t s town became c o n c e r n e d an a p p a r e n t c l u s t e r o f s i x l e u k e m i a c a s e s , d i a g n o s e d s i n c e 1969 i n c h i l d r e n o f f a m i l i e s l i v i n g i n a 6-block area i n the southeastern p o r t i o n o f t h e town (1970 t o t a l p o p u l a t i o n : 3 7 , 0 6 7 ) . The c l u s t e r was r e p o r t e d t o t h e M a s s a c h u s e t t s D e p a r t m e n t o f P u b l i c H e a l t h (MDPH) a n d t o t h e C e n t e r s f o r D i s e a s e C o n t r o l (CDC) b o t h by l o c a l c i t i z e n s and a B o s t o n p h y s i c i a n . C o n c e r n was a l s o e x p r e s s e d r e g a r d i n g o t h e r cancers, e s p e c i a l l y kidney cancer. An a s s e s s m e n t o f t o w n - s p e c i f i c c a n c e r m o r t a l i t y r a t e s made i n d e p e n d e n t l y by MDPH a t a b o u t t h e same t i m e f o r t h e 1969-1978 d e c a d e i n M a s s a c h u s e t t s showed statistically significan e l e v a t i o n i Wobur f o a l l as w e l l as f o r s e v e r a The c o n c e r n about e x c e s s c a n c e r s f o c u s e d on p o s s i b l e c a u s e s r e l a t e d t o t o x i c w a s t e d i s p o s a l s i t e s i n t h e town. From t h e m i d - 1 9 t h c e n t u r y u n t i l t h e 1 9 2 0 s , Woburn h a d b e e n a m a j o r c e n t e r f i r s t f o r c o m m e r c i a l t a n n i n g o f h i d e s and l a t e r f o r chemical production o f lead a r s e n i c a l p e s t i c i d e s . Efforts i n t h e 1970 s t o d e v e l o p an i n d u s t r i a l p a r k i n t h e n o r t h e a s t e r n p a r t o f t h e town u n c o v e r e d s e v e r a l o l d abandoned w a s t e d i s p o s a l s i t e s containing hides or chemicals r e l a t e d to p r i o r i n d u s t r i a l activities. Among t h e t o x i c c h e m i c a l s f o u n d i n e x c e s s i v e amounts were a r s e n i c , l e a d , chromium, and cadmium. C o n c e r n about l e a c h i n g of waste chemicals i n t o d r i n k i n g water l e d t o e x t e n s i v e t e s t i n g o f w e l l s w h i c h s u p p l y t h e town's w a t e r . Two o f 11 s u c h w e l l s showed e x c e s s i v e l e v e l s o f v a r i o u s o r g a n i c c h e m i c a l s ( t r i c h l o r o e t h y l e n e , f o r example). These two w e l l s h a d s u p p l i e d w a t e r , p r i n c i p a l l y t o t h e e a s t e r n h a l f o f t h e town, s i n c e t h e m i d 1960 s and were l o c a t e d a s h o r t d i s t a n c e t o t h e n o r t h o f t h e leukemia c l u s t e r neighborhood. Because o f t h e demonstrated c h e m i c a l l e v e l s , t h e w e l l s were c l o s e d i n 1979. To e x p l o r e t h e p o s s i b l e c a u s e o f r e p o r t e d c a n c e r e x c e s s e s , and p a r t i c u l a r l y t o examine t h e p o s s i b l e r e l a t i o n s h i p between t h e town's t o x i c w a s t e s i t u a t i o n and t h e c h i l d h o o d l e u k e m i a c a s e c o n c e n t r a t i o n , MDPH and CDC, i n 1980, c o n d u c t e d a j o i n t s t u d y . I n c i d e n c e p a t t e r n s f o r s e l e c t e d t y p e s o f c a n c e r were s t u d i e d by u s i n g d a t a c o l l e c t e d from l o c a l and r e g i o n a l h o s p i t a l s o u r c e s . I n c r e a s e d f r e q u e n c i e s f o r c h i l d h o o d l e u k e m i a and f o r k i d n e y c a n c e r were c o n f i r m e d , w i t h t h e c h i l d h o o d l e u k e m i a e x c e s s b e i n g l o c a t e d i n one p a r t i c u l a r c e n s u s t r a c t . S h i f t i n g e p i d e m i o l o g i c g e a r s t o c a s e - c o n t r o l methods, i n v e s t i g a t o r s then obtained a d d i t i o n a l data r e g a r d i n g a wide range o f p o s s i b l e e n v i r o n m e n t a l causes through d e t a i l e d i n t e r views w i t h p a t i e n t s o r r e l a t i v e s o f p a t i e n t s . F o r a l l 12 c h i l d hood l e u k e m i a c a s e s i n t h e town, t h i s p r o c e s s i n c l u d e d i n t e r v i e w s w i t h two a g e - and s e x - m a t c h e d c o n t r o l s drawn from s c h o o l e n r o l l ment l i s t s — o n e f r o m t h e m a t c h e d c a s e n e i g h b o r h o o d , t h e o t h e r f

1

1

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

3.

Ηουκ

Impacts on Human Health

f r o m a n o t h e r p a r t o f t h e town. No c a u s a l f a c t o r s were f o u n d from t h e s e i n t e r v i e w d a t a f o r e i t h e r k i d n e y c a n c e r o r l e u k e m i a . F o r l e u k e m i a i n p a r t i c u l a r , no c l e a r - c u t d i f f e r e n c e s were s e e n i n r e s p o n s e s p r o v i d e d by c a s e and c o n t r o l f a m i l i e s . The l i m i t a t i o n s o f t h e s e o b s e r v a t i o n s c a n be d e s c r i b e d i n terms o f t h e g e n e r a l p r o b l e m s a s s o c i a t e d w i t h s u c h t o x i c w a s t e studies. The h e a l t h outcome o f c o n c e r n ( c a n c e r , s p e c i f i c a l l y c h i l d h o o d leukemia) i s a r e l a t i v e l y r a r e disease. The t o x i c chemical exposure of p a r t i c u l a r persons h a v i n g these d i s e a s e s c o u l d n o t be d i r e c t l y documented, s i n c e t h e o r g a n i c c h e m i c a l s f o u n d i n w e l l w a t e r were t r a n s i e n t . T h e r e f o r e , no means were a v a i l a b l e f o r l i n k i n g p a r t i c u l a r leukemia cases to p a r t i c u l a r t o x i c s u b s t a n c e s . F o r t h e p r e s e n t , t h e n , we a r e l e f t w i t h an apparent leukemia cas a s s o c i a t i n g cases w i t p r o b l e m s c l e a r l y p r e s e n t i n t h e town. T r i a n a , Alabama - An E x a m p l e o f a C r o s s - s e c t i o n a l

Study

T r i a n a , w i t h a p o p u l a t i o n o f 600, i s l o c a t e d a t t h e c o n f l u e n c e o f I n d i a n C r e e k and t h e T e n n e s s e e R i v e r . From 1947 u n t i l 1971 DDT was m a n u f a c t u r e d i n a p l a n t 10 k i l o m e t e r s f r o m Triana. S e v e r a l t h o u s a n d t o n s o f DDT i n d u s t r i a l w a s t e accumu­ l a t e d i n the sediments of a t r i b u t a r y o f I n d i a n Creek. Locally c a u g h t f i s h have had t o t a l DDT r e s i d u a l l e v e l s up t o 100 t i m e s t h e t o l e r a n c e o f 5 p a r t s p e r m i l l i o n (ppm) s e t by t h e Food and Drug A d m i n i s t r a t i o n . The h i g h l e v e l s o f DDT r e s i d u e s i n t h e 12 p e r s o n s s u r v e y e d w e r e s u s p e c t e d o f r e s u l t i n g f r o m t h e i r c o n s u m i n g f i s h w h i c h had a c c u m u l a t e d DDT f r o m s e d i m e n t s . The t a s k a t hand was t o measure r e s i d e n t s ' e x p o s u r e t o DDT and r e l a t e i t , i f p o s s i b l e , to h e a l t h e f f e c t s i n the p o p u l a t i o n — a n example o f a c r o s s - s e c t i o n a l s t u d y . Of t h e 518 p e r s o n s p a r t i c i p a t i n g i n t h e s t u d y , i n c l u d i n g 44 c o m m e r c i a l f i s h e r m e n and t h e i r f a m i l i e s , 96.3 p e r c e n t gave b l o o d specimens. The mean serum DDT l e v e l (76.2 p a r t s p e r b i l l i o n ( p p b ) ) o f 499 p e r s o n s l i v i n g downstream f r o m t h e DDT m a n u f a c t u r i n g p l a n t was about f o u r t i m e s t h e n a t i o n a l mean (16.7 p p b ) . The number o f p a r t i c i p a n t s w i t h h i g h serum l e v e l s o f DDT was s m a l l , and t h e r e f o r e no sound c o n c l u s i o n s c o u l d be drawn from the s t u d y , r e g a r d l e s s of the time i n v o l v e d . On t h e o t h e r h a n d , t h e p o p u l a t i o n was l a r g e enough f o r t h e s t u d y t o i n c r e a s e u n d e r s t a n d i n g on s e v e r a l p o i n t s — n a m e l y , t h a t DDT a p p e a r s t o a c c u m u l a t e w i t h age, t h a t t h e l i v e r i s a f f e c t e d , and t h a t serum t r i g l y c e r i d e s and c h o l e s t e r o l l e v e l s a r e r e l a t e d t o DDT l e v e l . F u r t h e r , i n t h e c i t i z e n s o f T r i a n a , l e v e l s o f PCB's i n serum were f o u n d t o c o r r e l a t e p o s i t i v e l y w i t h b l o o d p r e s s u r e c e r t a i n l i v e r f u n c t i o n t e s t s , and c h o l e s t e r o l , i n d e p e n d e n t l y o f age and s e x .

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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B u c k s and Montgomery C o u n t y , P e n n s y l v a n i a - An E x a m p l e o f a P o t e n t i a l Cohort Study I n May 1979, t h e P e n n s y l v a n i a D e p a r t m e n t o f H e a l t h r e p o r t e d t h a t s e v e r a l p u b l i c and p r i v a t e w a t e r s u p p l i e s i n Montgomery C o u n t y , P e n n s y l v a n i a ( p o p u l a t i o n 627,600) were c o n t a m i n a t e d w i t h t r i c h l o r o e t h y l e n e (TCE). TCE was f o u n d i n 70 o f 100 w e l l - w a t e r s u p p l i e s i n Rahns, P e n n s y l v a n i a . Ten o f t h e s e p o s i t i v e s a m p l e s showed l e v e l s o f TCE i n e x c e s s o f 500 ppb, and 5 s a m p l e s showed TCE i n e x c e s s o f 1,000 ppb. The s u s p e c t e d s o u r c e o f c o n t a m i n a t i o n was a s t e e l w i r e and r o d m i l l t h a t u s e d t h i s compound as a d e g r e a s i n g agent. I m p r o p e r d i s p o s a l r e s u l t e d i n s p i l l s on p l a n t p r o p e r t y , w h i c h l e a c h e d i n t o n e a r b y l a g o o n s and w e l l w a t e r s u p p l i e s . A t a n o t h e r t u b e company, a p i p e f e e d i n g a l a r g e s t o r a g e t a n k o f TCE r u p t u r e d and s p i l l e d o v e r 2,000 g a l l o n s o f TCE i n t o a s t o r m sewer s u r f a c e and g r o u n d w a t e r A p p a r e n t l y , h u n d r e d s o f p e o p l e were b e i n g e x p o s e d t o TCE through t h e i r d r i n k i n g water. No a c u t e i l l n e s s had been r e p o r t e d t o be r e l a t e d t o t h e c o n t a m i n a t e d w e l l w a t e r , b u t C o n g r e s s i o n a l r e q u e s t s and a h i g h d e g r e e o f c o n c e r n f r o m c i t i z e n s and l o c a l o f f i c i a l s led to f u r t h e r study. Seven ( 6 % ) o f 117 r e s i d e n t s s c r e e n e d f o r t r i c h l o r o metabol i t e s had d e t e c t a b l e l e v e l s o f t r i c h l o r o e t h a n o l and t r i c h l o r o a c e t i c a c i d i n t h e i r u r i n e . The a p p r o a c h u s e d i n t h i s i n v e s t i g a t i o n was t o s p e c i f i c a l l y compare d e a t h s f r o m l i v e r c a n c e r i n Montgomery C o u n t y w i t h s u c h d e a t h s i n u n e x p o s e d p o p u l a t i o n s w i t h i n t h e same c o u n t y as t h e p r i m a r y c o m p a r i s o n g r o u p and w i t h p o p u l a t i o n s r e p r e s e n t e d by S t a t e and n a t i o n a l d a t a as a l t e r n a t e comparison groups. To a c e r t a i n d e g r e e , t h i s s i t u a t i o n l e n d s i t s e l f t o a p r o s p e c t i v e c o h o r t s t u d y . Had t h i s e p i d e m i o l o g i c t o o l b e e n e m p l o y e d , a d i s c r e t e p o p u l a t i o n o f e x p o s e d , and p e r h a p s u n e x p o s e d , i n d i v i d u a l s w o u l d have been r e g i s t e r e d , w i t h a p p r o p r i a t e i d e n t i f i e r s , and a s s i g n e d a p a r t i c u l a r e x p o s u r e level. T h i s p o p u l a t i o n w o u l d t h e n be a c t i v e l y f o l l o w e d f o r a minimum o f 15 t o 20 y e a r s , and v i t a l s t a t u s and any d e s i g n a t e d a d v e r s e h e a l t h outcomes w o u l d be r e c o r d e d and compared w i t h t h e S t a t e o r n a t i o n a l r a t e s f o r t h e same e v e n t . Obviously, a very l o n g t i m e i s r e q u i r e d and f o l l o w u p i s v e r y e x p e n s i v e . However, i n f o r m a t i o n o b t a i n e d f r o m a p r o s p e c t i v e c o h o r t s t u d y w h i c h i s w e l l d e s i g n e d and m e t i c u l o u s l y c o n d u c t e d c a r r i e s tremendous w e i g h t when one i s b a l a n c i n g i n f o r m a t i o n f r o m l e s s powerful i n v e s t i g a t i v e t o o l s . These p r o s p e c t i v e c o h o r t s t u d i e s must be w e l l t h o u g h t o u t , and t h e r e s h o u l d be a r e a s o n a b l e p o s s i b i l i t y f o r f u n d i n g through the l i f e of the study. An a l t e r n a t i v e t o t h e p r o s p e c t i v e c o h o r t s t u d y i s t h e r e t r o s p e c t i v e cohort study, i n which a defined population w i t h a p a s t e x p o s u r e has an e x i s t i n g m e a s u r a b l e h e a l t h outcome. The p a s t e x p o s u r e needs t o be w e l l documented so t h a t a g i v e n l e v e l o f e x p o s u r e c a n be a s s i g n e d t o e a c h i n d i v i d u a l i n t h e p o p u l a t i o n .

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

3.

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31

T h i s , o f c o u r s e , r e q u i r e s a c c u r a t e and a c c e s s i b l e e x p o s u r e r e c o r d s w h i c h c a n be r e a d i l y c o u p l e d t o t h e p o p u l a t i o n b e i n g viewed r e t r o s p e c t i v e l y . Thus, we have t h r e e s i t u a t i o n s i n w h i c h f o u r d i f f e r e n t e p i d e m i o l o g i c a p p r o a c h e s c o u l d be u s e d t o i n v e s t i g a t e h e a l t h e f f e c t s a s s o c i a t e d w i t h h a z a r d o u s w a s t e s i t e s o r any e n v i r o n mental contamination. I n summary, w i t h t h e i n c r e a s i n g p u b l i c c o n c e r n about t o x i c w a s t e s g r o w i n g o u t o f s u c h i n c i d e n t s as L o v e C a n a l , i t i s incumbent upon t h e F e d e r a l Government t o t r y t o answer t h e public's question: "How i s my h e a l t h , and t h a t o f my f a m i l y , a f f e c t e d by e x p o s u r e t o t o x i c w a s t e s ? " I f I c a n l e a v e y o u w i t h o n l y one message, i t i s t h a t t h i s q u e s t i o n i s e x t r e m e l y d i f f i c u l t t o answer. As I have shown t h e p i d e m i o l o g i s t th i n v e s t i g a t o t a k e any one o r s e v e r a possible health effect exposur g i v e n dump s i t e o r c h e m i c a l s p i l l . Each approach has i t s s t r e n g t h s and w e a k n e s s e s . S i m i l a r l y , e a c h dump s i t e o r s p i l l has i t s p e c u l a r i t i e s . We a r e i n t h e p r o c e s s o f m a t c h i n g what i s known about t h e p r i o r i t y s i t e s t o be c l e a n e d up u n d e r t h e S u p e r f u n d l a w w i t h t h e b e s t a p p r o a c h t o l e a r n i n g about t h e p o s s i b l e h e a l t h e f f e c t s on exposed people l i v i n g around those sites. Once we have s o r t e d o u t t h e s i t e s most l i k e l y t o g i v e us a n s w e r s about h e a l t h e f f e c t s and have d e s i g n e d t h e b e s t r e s e a r c h s t r a t e g y f o r s t u d y i n g e a c h s i t e , we c a n b e g i n o u r work i n t h e field. T h i s work p r o m i s e s t o be d i f f i c u l t and c o m p l e x , b u t we hope i t w i l l r e s o l v e t h e s e p u b l i c h e a l t h c o n c e r n s . Literature 1.

2.

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American Conference o f Governmental Industrial Hygienists (ACGIH). " T h r e s h o l d limit v a l u e s for c h e m i c a l s u b s t a n c e s and physical a g e n t s in the workroom e n v i r o n m e n t with i n t e n d e d changes for 1980." Publication Office, ACGIH, PO Box 1 9 3 7 , Cincinnati, OH 45201. Cannon, S.B.; V e a z e y , J.M.; J a c k s o n , R.S.; Burse, V.W.; H a y e s , C.; S t r a u b , W.E.; L a n d r i g a n , P.J.; Liddle, J.A. E p i d e m i c kepone poisoning in chemical w o r k e r s . Am. J. Epid, 1978, 1 0 7 , 529-537. C h r i s t e n s e n , H.E.; Fairchild, E . J . "Suspected carcinogens," 2nd e d . , U.S.DHEW, NIOSH, Government Printing Office, Supt. of Doc., W a s h i n g t o n , DC 20402. Crump, K.S.; M a s t e r m a n , M.D. R e v i e w and evaluation o f methods of d e t e r m i n i n g risks f r o m chronic l o w level carcinogenic insult in " E n v i r o n m e n t a l c o n t a m i n a n t s in food," C o n g r e s s o f the U n i t e d States, 1979, Libr. C o n g r . C a t . No. 79-600207. S u p t . o f Doc., U.S. G o v t . Printing Office, W a s h i n g t o n , DC 20402. S t o c k No. 052-00300724-0.

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12.

13. 14. 15.

C a r t e r , C . D . ; Kimbrough, R . D . ; Liddle, J.Α.; C l i n e , R.E.; Zack, M . M . , J r . B a r t h e l , W.F.; K o e h l e r , R.E.; Phillips, P . E . T e t r a c h l o r o d i b e n z o - d i o x i n : An a c c i d e n t a l poisoning episode in horse arenas. S c i e n c e , 1975, 188, 738-740. Dunphy, J.H.; Hail, A. Waste d i s p o s a l : It's a dirty b u s i n e s s . Chemical Week, March 1, 1978, pp. 25-29. Brown, C . C . Mathematical aspects of dose response s t u d i e s i n carcinogenesis: The concept of t h r e s h o l d s . Oncology, 1976, 32, 62-65. Dunphy, J.H.; Hall, A . Waste d i s p o s a l : S e t t l i n g on safer solution for chemicals. Chemical Week, March 8, 1978, pp. 28-32. Guess, H.; Crump, K.; P e t o , R. U n c e r t a i n t y estimates f o r low-dose-rate e x t r a p o l a t i o n s of animal c a r c i n o g e n i c i t y d a t a . Cancer Research, 1977 37, 3475-3483 Hoel, D . G . ; Gaylor Schneiderman, M . A . ; delayed toxicity, J . Tox. & Env. H e a l t h , 1975, 1, 133-151. Johnson, C . J . Toxic s o l u b l e waste d i s p o s a l in a s a n i t a r y landfill site d r a i n i n g to an urban water s u p p l y . AJPH, 1977, 67, 468-469 K r e i s s , K.; Zack, M . M . ; Kimbrough, R . D . ; Needham, L.L.; Smrek, A.L.; Jones, B . T . C r o s s - s e c t i o n a l study of a community w i t h e x c e p t i o n a l exposure to DDT. JAMA, 1981, 245, 1926-1930. Schmahl, D. Combination e f f e c t s i n chemical carcinogenesis (experimental results). Oncology, 1976, 2 3 , 73-76. W o l f f , A.H.; Oehme, F.W. Carcinogenic chemicals in food as an environmental i s s u e . JAVMA, 1974, 164, 623-629. "Chemical and Health Report, 1973," United States I n t e r ­ n a t i o n a l Trade Commission Reports on P r o d u c t i o n and Sale of S y n t h e t i c Organic Chemicals, 1918-1976.

RECEIVED July 16,

1982.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

4 Analysis and Risk Assessment: Key to Effective Handling of Hazardous Waste Sites DONALD L. BAEDER Occidental Petroleum Corporation, Los Angeles, CA 90024

The real key to effective management of hazardous waste disposal site a responsibl measure levels of potential or actual human exposure, which includes comparison with other relevant areas a comparative base of toxicological and epidemiological information an assessment of risk based on these two fact bases an independent check by qualified experts separated from political and emotional factors Omitting one or more of these actions before releasing information d i r e c t l y to the public i s an unconscionable risk that should never be taken. In fact, it could well introduce an even greater r i s k of irreparable psychological harm. Love Canal, which i s discussed i n d e t a i l , i s the primary example where these actions were not taken by governmental agencies. The real key to effective management of hazardous waste disposal sites i s : a responsible a n a l y t i c a l base to accurately measure levels of potential or actual human exposure, which includes comparison with other relevant areas a comparative base of toxicological and epidemiol o g i c a l information an assessment of r i s k based on these two fact bases an independent check by qualified experts separated from political and emotional factors Omitting one or more of these actions before releasing information to the public regardless of what may be required to be reported to an agency, such as under Section 8(e) of the Toxic Substances Control Act, is an unconscionable r i s k that should never be taken. In fact, i t could well introduce an 0097-6156/82/0204-003 3$06.00/0 © 1982 American Chemical Society

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e v e n g r e a t e r r i s k o f i r r e p a r a b l e p s y c h o l o g i c a l harm. F o r t h e p a s t two y e a r s , t h e need f o r an i n d e p e n d e n t p e e r r e v i e w a s a n i n t e g r a l p a r t o f S u p e r f u n d h a s been f o r e m o s t i n my p r i o r i t y o f t h i n g s t o a c c o m p l i s h . The e v i d e n t i a r y need f o r s u c h a r e v i e w i s c o m p e l l i n g . U n l e s s i t i s done we c a n n o t e x p e c t e v e r t o e f f e c t i v e l y manage h a z a r d o u s w a s t e i n c i d e n t s . U n f o r t u n a t e l y , my e f f o r t s t o c o n v i n c e t h e c o m m i t t e e s w r i t i n g S u p e r f u n d f a i l e d . Today I have t h e o p p o r t u n i t y t o l a y b e f o r e y o u t h e e v i dence t h a t I f e e l i s c o m p e l l i n g t o f o r c e t h i s f o u r - p a r t a p p r o a c h t o d e f i n e human and e n v i r o n m e n t a l r i s k a s s o c i a t e d w i t h h a z a r d o u s w a s t e s i t e s — and t h a t i s what I i n t e n d t o do. I know some o f y o u w i l l s a y " A l l w e l l and good. When y o u h a v e p l e n t y o f t i m e . B u t what a b o u t t h e s i t u a t i o n s t h a t r e q u i r e immediate a c t i o n ? " I f y o u ' l l s t a y w i t h me, I ' l l a d d r e s s t h i s i s s u e l a t e r , b u t I w i l l s a y now t h a t t h e n e c e s s a r y r e v i e w c a n be done w i t h i t o make a d e c i s i o n . I w o u l d l i k e t o f l o o d y o u w i t h examples o f where p r o p e r a c t i o n s were t a k e n . U n f o r t u n a t e l y , t h e r e c o r d i s d i s m a l and s o we w i l l have t o p r o f i t f r o m o u r m i s t a k e s . I w i l l u s e L o v e C a n a l a s t h e p r i m a r y e x a m p l e , n o t o n l y b e c a u s e I am most f a m i l i a r w i t h i t , b u t b e c a u s e i t i s c l e a r l y t h e b e s t example. I f n o t h i n g e l s e , L o v e C a n a l has become a l m o s t a g e n e r i c t e r m . L e t ' s s t a r t w i t h t h e e v e n t s t h a t l e d t h e S t a t e Commissioner of Health to c a l l f o r a l i m i t e d evacuation of pregnant women and c h i l d r e n u n d e r two, w h i c h c a u s e d s u c h an u p r o a r among the r e s i d e n t s t h a t w i t h i n a few d a y s G o v e r n o r C a r e y was f o r c e d t o e v a c u a t e a l l t h e p e o p l e i n t h e f i r s t two r i n g s o f homes. On O c t o b e r 3, 1976, t h e f i r s t c o n f i r m e d r e p o r t s i s s u e d t h a t c h e m i c a l s had s e e p e d i n t o t h e basements o f some homes on the p e r i p h e r y o f t h e L o v e C a n a l p r o p e r t y . A government t a s k f o r c e comprised of the C i t y of Niagara F a l l s , the Niagara County H e a l t h D e p a r t m e n t a n d Hooker C h e m i c a l began t o s t u d y t h e situation. The C i t y a c t i n g a s t h e l e a d c o m m i s s i o n e d a c o n t r a c t o r t o p r e p a r e a r e p o r t w h i c h was r e c e i v e d by t h e C i t y i n A u g u s t , 1977. I n M a r c h 1978 t h e C i t y c o m m i s s i o n e d an o u t s i d e c o n t r a c t o r to d e s i g n a r e m e d i a l p r o g r a m . Hooker p a r t i c i p a t e d i n t h e s t u d y and o f f e r e d t o pay one t h i r d o f t h e t h e n - e x p e c t e d c o s t o f r e m e d i a l work w h i c h was e s t i m a t e d a t $840,000. On A u g u s t 2, 1978, t h e New Y o r k S t a t e H e a l t h D e p a r t m e n t o r d e r e d t h e temporary c l o s i n g o f t h e 99th S t r e e t S c h o o l and recommended t h e t e m p o r a r y e v a c u a t i o n o f p r e g n a n t women and c h i l d r e n u n d e r two l i v i n g i n t h e f i r s t two r i n g s o f homes around the Canal p r o p e r t y d u r i n g t h e c o m p l e t i o n of the r e m e d i a l program. A p p r o x i m a t e l y 20 f a m i l i e s c o u l d have been a f f e c t e d . On A u g u s t 9, 1978, G o v e r n o r C a r e y o f New Y o r k v i s i t e d t h e a r e a and announced t h a t a l l 236 f a m i l i e s l i v i n g on b o t h s i d e s of 9 7 t h and 9 9 t h S t r e e t ( t h e s t r e e t s b o r d e r i n g t h e C a n a l p r o p e r t y ) w o u l d be e v a c u a t e d and t h e i r homes p u r c h a s e d .

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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The d a t a b a s e f o r t h i s d e c i s i o n was two s t u d i e s . One c o v e r e d a i r s a m p l i n g i n t h e basements o f s e v e r a l h u n d r e d h o u s e s by t h e s t a t e and e l e v e n b y EPA, t h e o t h e r a l i m i t e d e p i d e m i o l o g i c a l s t u d y o f a d v e r s e p r e g n a n c y outcomes i n r e s i d e n t s o f t h e houses c l o s e s t t o the c a n a l . These d a t a c a n be u s e d t o s u p p o r t t h e need f o r t h e f i r s t two p o i n t s m e n t i o n e d a b o v e . That i s : a r e s p o n s i b l e a n a l y t i c a l b a s e t o a c c u r a t e l y measure l e v e l s o f p o t e n t i a l o r a c t u a l human e x p o s u r e , w h i c h i n c l u d e s comparison w i t h o t h e r r e l e v a n t areas a c o m p a r a t i v e b a s e o f t o x i c o l o g i c a l and e p i d e m i o logical information W h i l e a n a n a l y t i c a l d a t a b a s e was d e v e l o p e d , t h e d a t a was not e v a l u a t e d i n comparison w i t h o t h e r t y p i c a l l o c a t i o n s . I n a d d i t i o n , t h e epidemiology d i d not use an a p p r o p r i a t e c o n t r o l group. Rather than use an e q u i v a l e n t l o c a l p o p u l a t i o n not s u b j e c t t o t h e same e x p o s u r e n a t i o n a l averages. I v a r i a t i o n s i n r a t e s i n s m a l l groups w i t h i n a l a r g e p o p u l a t i o n . F o r t h i s r e a s o n , t h e c o n t r o l and t e s t p o p u l a t i o n s h o u l d have s i m i l a r s i z e as w e l l as background except f o r t h e t h e s i s b e i n g tested. Comparison o f t h e h i g h e s t v a l u e a i r samples from basements as t e s t e d by New Y o r k S t a t e and EPA and c o m p a r i n g t h e r e s u l t s w i t h U.S. w o r k p l a c e s t a n d a r d s ( w h i c h a r e b a s e d o n 8 h o u r e x p o s u r e , n o t l i v i n g a t home) shows t h a t t h e l e v e l s measured were o r d e r s o f m a g n i t u d e l o w e r t h a n t h e p u b l i s h e d w o r k p l a c e s t a n d a r d s f o r t h e s e v e r a l common s o l v e n t s d e t e c t e d . COMPARISON OF HIGHEST VALUE A I R SAMPLE CONCENTRATIONS INSIDE BASEMENTS WITH WORKPLACE (parts per b i l l i o n )

Compound Chloroform Trichloroethylene Tetrachloroethylene Chlorobenzene Chlorotoluene

N.Y. S t a t e Highest Value

EPA Highest Value

STANDARDS

Permissible U.S. Workplace Standards

5

3.0

10,000

13

2.7

100,000

170

7.0

100,000

52

0.8

75,000

40.0

50,000

1,300

These s t a n d a r d s a r e s e t by a n e x p e r t c o m m i t t e e o f t h e A m e r i c a n C o n f e r e n c e o f G o v e r n m e n t a l I n d u s t r i a l H y g i e n i s t s who

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e s t a b l i s h these v a l u e s based on t h e a v a i l a b l e m e d i c a l / t e c h n i c a l l i t e r a t u r e and t h e i r p r o f e s s i o n a l judgment. Please note that these a r e highest values. The mean l e v e l s a r e t y p i c a l l y 1/10 t o 1/1,000 o f t h e h i g h e s t v a l u e s . A l l s a m p l e s shown were f o r basement a i r . S e v e r a l r i n g 1 homes were a n a l y z e d f o r c h e m i c a l s o n t h e f i r s t f l o o r . O n l y i n t h e c a s e o f one home were m e a s u r a b l e l e v e l s f o u n d o n t h e f i r s t floor. C h e m i c a l l e v e l s d e t e c t e d i n b a s e m e n t s o f homes b e y o n d t h e f i r s t r i n g were s h a r p l y l o w e r t h a n f o r homes i n r i n g 1. The mean l e v e l s f o r r i n g 2 w e r e 5 p e r c e n t o f t h e mean f o r r i n g 1. I n a d d i t i o n , d a t a shows t h a t o u t d o o r a i r i n t h e L o v e C a n a l A r e a was c o m p a r a b l e o r b e t t e r t h a n i n o t h e r m a j o r c i t i e s . EPA CONTRACTOR DATA COMPARISO AT LOV (parts per b i l l i o n ) Compound

Love

Canal

Rahway

Phoenix

Chloroform

7.3

5.2

0.1

Trichloroethylene

0.02

9.9

0.5

Tetrachloroethylene

0.3

3.5

1.0

Chlorobenzene

0.003

0.1

0.2

Chlorotoluene

0.09

*

*

*

Not analyzed f o r

I t i s i n t e r e s t i n g t o note t h a t an a r t i c l e i n t h e B u f f a l o C o u r i e r E x p r e s s d a t e d September 2 3 , 1978 h e a d l i n e d " S t u d y Shows ' C a n a l A i r B e a t s L.A." t r i e d t o p u t e x p o s u r e l e v e l s i n p e r s p e c t i v e by c o m p a r i n g d a t a f o r basement benzene a n d t o l u e n e l e v e l s with atmospheric concentrations i n Los Angeles, as posted i n t h e o f f i c e o f a Dr. P h i l i p T a y l o r , then o n - s i t e d i r e c t o r f o r t h e s t a t e H e a l t h Department. The b e n z e n e l e v e l s m e a s u r e d i n b a s e m e n t s o f t h e f i r s t r i n g o f h o u s e s a v e r a g e d o n l y one f i f t h t h e o u t s i d e a t m o s p h e r e i n L o s Angeles. Toluene l e v e l s i n t h e f i r s t r i n g basements were 50% higher. I n t h e s e c o n d r i n g , b e n z e n e was one t e n t h t h e L o s A n g e l e s a v e r a g e and t o l u e n e one q u a r t e r . As f a r a s we know, t h i s a p p r o a c h was n o t u s e d a g a i n . When one l o o k s a t t h e l i m i t e d e p i d e m i o l o g i c a l s t u d y o f a d v e r s e p r e g n a n c y outcomes i n r e s i d e n t s o f t h e h o u s e s c l o s e s t t o t h e c a n a l one f i n d s t h e p o p u l a t i o n c o n s i d e r e d was v e r y s m a l l s i n c e a t o t a l o f o n l y 236 f a m i l i e s were i n v o l v e d . One segment o f t h e p o p u l a t i o n showed a h i g h e r t h a n a v e r a g e r a t e w h i l e t h e 1

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o t h e r showed a l o w e r t h a n a v e r a g e r a t e , n e i t h e r v e r y s i g n i f i cantly different. I f c o m b i n e d , t h e r a t e was l o w e r t h a n t h e n a t i o n a l average. Panic r a t h e r than reason p r e v a i l e d . The New York H e a l t h Department j u s t i f i e d i t s p o s i t i o n by i s s u i n g a b o o k l e t i n September 1978 e n t i t l e d , "Love C a n a l — P u b l i c H e a l t h Time Bomb," w h i c h d e s c r i b e d t h e L o v e C a n a l s i t u a t i o n a s an " e n v i r o n m e n t a l n i g h t m a r e " c a p a b l e o f c a u s i n g " p r o f o u n d a n d d e v a s t a t i n g e f f e c t s " c o n s t i t u t i n g a c o n d i t i o n o f " g r e a t and imminent p e r i l . " The i n f l a m m a t o r y n a t u r e o f t h i s p a m p h l e t a n d t h e c o n c e r n o f t h e l o c a l r e s i d e n t s was f u r t h e r e x a c e r b a t e d by a " s t u d y " b y Dr. B e v e r l y P a i g e n , o f R o s w e l l P a r k M e m o r i a l I n s t i t u t e (RPMI) i n F e b r u a r y 1979, u r g i n g t h e e v a c u a t i o n o f f a m i l i e s i n l i g h t o f her study suggesting a h i g h r a t e o f b i r t h d e f e c t s . The P a i g e n s t u d y was c o m p l e t e d a f t e r t h e e v a c u a t i o n o f t h e f i r s t and s e c o n d r i n g not concur w i t h h e r f i n d i n g w i t h c e r t a i n t y t h a t t h e h i g h e r r a t e s found i n each o f t h e c a t e g o r i e s a r e d i r e c t l y r e l a t e d t o chemical exposure b u t t h e d a t a do s u g g e s t a s m a l l b u t s i g n i f i c a n t i n c r e a s e i n t h e r i s k s o f m i s c a r r i a g e s and b i r t h d e f e c t s . A l t h o u g h t h e m a g n i t u d e o f t h e a d d i t i o n a l r i s k i s i n d e e d s m a l l , p r u d e n c e d i c t a t e s t h a t we t a k e a more c o n s e r v a t i v e p o s t u r e t o m i n i m i z e even t h a t s m a l l additional risk." B a s e d o n t h i s , h e recommended t e m p o r a r y r e l o c a t i o n o f c h i l d r e n u n d e r t h e age o f two and p r e g n a n t women f r o m t h e a r e a beyond t h e s e c o n d r i n g o f homes — a n o t h e r 700 families. N o t e t h a t D r . P a i g e n d i d n o t do t h i s " s t u d y " a t R o s w e l l P a r k and i t was o u t s i d e h e r a r e a o f e x p e r t i s e . She i s a b i o l o g i s t and n o t a t o x i c o l o g i s t . T h e r e was no p e e r r e v i e w and t h e " s t u d y " was t a k e n a t f a c e v a l u e , f u r t h e r a d d i n g t o t h e panic. I t i s c l e a r t h a t the key p o i n t s mentioned a t the o u t s e t were n o t f o l l o w e d h e r e s i n c e a c o m p a r a t i v e b a s e o f e x p o s u r e l e v e l s and e p i d e m i o l o g i c a l i n f o r m a t i o n was n o t u s e d , n o r was t h e r e a n i n d e p e n d e n t c h e c k by e x p e r t s s e p a r a t e d f r o m p o l i t i c a l and e m o t i o n a l f a c t o r s . I t was n o t u n t i l n i n e months l a t e r t h a t t h e s t a t e made a s t r o n g e f f o r t t o develop a peer review. On J u n e 4, 1980, New Y o r k G o v e r n o r Hugh L . C a r e y a p p o i n t e d a s p e c i a l b l u e r i b b o n p a n e l o f d i s t i n g u i s h e d p h y s i c i a n s , c h a i r e d b y L e w i s Thomas, M.D., C h a n c e l l o r o f M e m o r i a l S l o a n - K e t t e r i n g C a n c e r C e n t e r , t o "determine whether p r e v i o u s s t u d i e s v a l i d l y demonstrated a c u t e , c h r o n i c o r l o n g term h e a l t h e f f e c t s from exposure t o c h e m i c a l w a s t e s b u r i e d a t Love C a n a l . " On O c t o b e r 10, 1980 t h e P a n e l issued i t s report concluding that i t "...recognizes that there was a r e a s o n f o r t h e S t a t e H e a l t h D e p a r t m e n t ' s i n i t i a l announcement o f ' P u b l i c H e a l t h Time Bomb, b u t n o t a good enough r e a s o n . T h e r e o u g h t t o be a b e t t e r mechanism f o r c o n v i n c i n g t h e F e d e r a l government t h a t a c e r t i f i a b l e d i s a s t e r area e x i s t s , i n order t o o b t a i n F e d e r a l funds, than t o arouse 1

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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s u c h f e a r s o f i m m i n e n t p e r i l a s swept t h r o u g h t h e L o v e C a n a l area i n t h i s case." The G o v e r n o r ' s b l u e r i b b o n p a n e l , a y e a r and a h a l f l a t e r , l o n g a f t e r t h e p s y c h o l o g i c a l damage had been done by t h e r e p o r t , concluded that the Paigen report " . . . f a l l s f a r short of t h e mark a s an e x e r c i s e i n e p i d e m i o l o g y . She [ D r . P a i g e n ] b e l i e v e s f e r v e n t l y that her observations prove the e x i s t e n c e of m u l t i p l e , d i s e a s e states d i r e c t l y a t t r i b u t a b l e to chemical p o l l u t i o n , b u t h e r d a t a c a n n o t be t a k e n a s s c i e n t i f i c e v i d e n c e for her conclusions. The s t u d y i s b a s e d l a r g e l y on a n e c d o t a l i n f o r m a t i o n p r o v i d e d by q u e s t i o n n a i r e s s u b m i t t e d t o a n a r r o w l y s e l e c t e d group o f r e s i d e n t s . T h e r e a r e no a d e q u a t e c o n t r o l g r o u p s , t h e i l l n e s s e s c i t e d a s c a u s e d by c h e m i c a l p o l l u t i o n were n o t m e d i c a l l y v a l i d a t e d . . . The P a n e l f i n d s t h e P a i g e n r e p o r t l i t e r a l l y i m p o s s i b l e t o i n t e r p r e t . I t c a n n o t be t a k e n s e r i o u s l y as a p i e c e o does have t h e i m p a c t o A s t u d y w i t h t h i s many d e f e c t s c o u l d e a s i l y have b e e n i n i t i a l l y r e v i e w e d and s h o r t c o m i n g s n o t e d i n a f e w d a y s . The f a i l u r e o f t h e s t a t e t o a d e q u a t e l y r e v i e w s o - c a l l e d s t u d i e s was a l s o s h a r e d by t h e f e d e r a l government w h i c h added t o t h e c o n f u s i o n when on May 17, 1980, t h e EPA h e l d a p r e s s conference to release the r e s u l t s of a preliminary genetic s t u d y s h o w i n g chromosome damage o f 11 o f t h e 36 L o v e C a n a l r e s i d e n t s t e s t e d . The EPA r e c o g n i z e d t h a t t h e r e was no c o n t r o l group and t h a t " p r u d e n c e must be e x e r t e d i n t h e i n t e r p r e t a t i o n of such r e s u l t s . " The r e p o r t a l s o s t a t e d "we s t r o n g l y recommend t h e c y t o g e n e t i c a n a l y s i s o f a l a r g e r p o p u l a t i o n o f L o v e C a n a l r e s i d e n t s a l o n g w i t h a number o f u n e x p o s e d i n d i v i d u a l s ( c o n t r o l s ) b e f o r e s i g n i f i c a n c e c a n be p l a c e d upon t h e r e s u l t s . " H o o k e r i t s e l f c a l l e d f o r an i m m e d i a t e f o l l o w u p on t h e EPA study. The f e d e r a l government was a b l e t o o b t a i n i m m e d i a t e p e e r r e v i e w and on May 2 1 , 1980 a s p e c i a l p a n e l c o n v e n e d by t h e U.S. D e p a r t m e n t o f H e a l t h and Human S e r v i c e s i n e s s e n c e b l a s t e d t h e EPA g e n e t i c r e p o r t . The p a n e l s t a t e d t h a t " I t p r o v i d e s i n a d e q u a t e b a s i s f o r any s c i e n t i f i c o r m e d i c a l i n f e r e n c e s from t h e data (even o f a t e n t a t i v e o r p r e l i m i n a r y n a t u r e ) concerning exposure t o mutagenic substances because o f r e s i dence i n t h e L o v e C a n a l a r e a . " The p a n e l a l s o i n d i c a t e d t h a t "we do n o t b e l i e v e t h a t on t h e b a s i s o f t h i s r e p o r t i t s h o u l d be c o n c l u d e d t h a t t h e c h e m i c a l e x p o s u r e o f L o v e C a n a l may be r e s p o n s i b l e f o r much o f t h e a p p a r e n t i n c r e a s e n o r c a n we c o n c u r with the report's i m p l i c a t i o n that a cytogenic observation suggests t h a t t h e r e s i d e n t s a r e an i n c r e a s e d r i s k o f n e o p l a s t i c d i s e a s e , o f h a v i n g s p o n t a n e o u s a b o r t i o n s and o f h a v i n g c h i l d r e n w i t h b i r t h d e f e c t s b a s e d on t h e e v i d e n c e p r e s e n t e d . " The EPA s t u d y was i n a d e q u a t e , b u t a g a i n t h e r e l e a s e t h r e e d a y s e a r l i e r o f an i n a d e q u a t e r e p o r t had c r e a t e d o t h e r m a j o r problems.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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N o t e t h a t t h e EPA s t u d y was c o m m i s s i o n e d b y government a t t o r n e y s b u i l d i n g a l e g a l a c t i o n , and s e l e c t e d s u b j e c t s f o r the study not from a normal c r o s s - s e c t i o n o f the p u b l i c a t risk. "The EPA s t u d y , h o w e v e r , was n o t w e l l d e s i g n e d . I t was n o t even meant t o be s c i e n t i f i c , a c c o r d i n g t o S t e p h e n Gage, a s s i s t a n t a d m i n i s t r a t o r f o r r e s e a r c h and d e v e l o p m e n t a t EPA. T h i s [ t h e s t u d y ] was a s m a l l f i s h i n g e x p e d i t i o n . The J u s t i c e Department asked us t o u n d e r t a k e i t i n c o n n e c t i o n w i t h our s u i t a g a i n s t Hooker, he s a y s . " 208 S c i e n c e , J u n e 13, 1980, p . 1239. The EPA "chromosome" d e b a c l e s o i n f l a m e d t h e l o c a l r e s i d e n t s t h a t t h e y k e p t two EPA o f f i c i a l s h o s t a g e f o r s e v e r a l h o u r s . L o i s G i b b s , t h e p r e s i d e n t o f t h e Homeowner's A s s o c i a t i o n , i n d i c a t e d t h a t " t h i s a c t i o n was a ' d i r e c t r e s u l t ' o f t h e s t u d y b e i n g r e l e a s e d w i t h nobody t o t e l l u s what i t meant o r what t h e y were g o i n g t o do a b o u t i t ! I f t h e EPA o f f i c i a l s h a d been l e t o u t t h e f r o n apart. " Love C a n a l R e s i d e n t J u n e 13, 1980, a t p. 1242. f

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A " p o l i t i c a l " d e c i s i o n i s s u e d o n t h e same day a s t h e p e e r r e v i e w b l a s t e d t h e EPA s t u d y . A f t e r t h e EPA o f f i c i a l s had b e e n h e l d h o s t a g e , P r e s i d e n t C a r t e r d e c l a r e d a s t a t e o f emergency i n t h e L o v e C a n a l a r e a , p a v i n g the way f o r e v a c u a t i o n o f up t o 710 families. G o v e r n o r C a r e y c o n c l u d e d i n a newspaper i n t e r v i e w o n May 31, 1980 t h a t " a c o s t l y r e l o c a t i o n o f more t h a n 700 L o v e C a n a l homeowners i s m e d i c a l l y u n n e c e s s a r y b u t had t o b e c a r r i e d o u t t o a s s u a g e t h e p a n i c c a u s e d by t h e EPA r e p o r t . " The D i r e c t o r of the S t a t e ' s O f f i c e o f P u b l i c H e a l t h s a i d t h a t based on s t u d i e s g o i n g o n s i n c e 1978 t h e f r e q u e n c y o f b i r t h p r o b l e m s o f t h e r e s t o f t h e L o v e C a n a l ( o t h e r t h a n t h e f i r s t 230 r e l o c a t e d f a m i l i e s ) was c o m p a r a b l e t o t h a t o f N i a g a r a C o u n t y . " A g a i n we see a s i g n i f i c a n t community e f f e c t r e s u l t i n g f r o m a f a i l u r e t o p r o p e r l y manage t h e a s s e s s m e n t o f r i s k . Informat i o n was r e l e a s e d b a s e d o n a n i n a p p r o p r i a t e a n a l y t i c a l b a s e w i t h o u t adequate e p i d e m i o l o g i c a l i n f o r m a t i o n o r independent review. On J u n e 24, 1980, t h e New Y o r k D e p a r t m e n t o f H e a l t h Commissioner f i n a l l y i s s u e d the Department's e p i d e m i o l o g i c a l s t u d i e s o n A d v e r s e P r e g n a n c y Outcomes i n t h e L o v e C a n a l A r e a , c o n c l u d i n g t h a t "we have n o t y e t b e e n a b l e t o c o r r e l a t e t h e g e o g r a p h i c d i s t r i b u t i o n o f a d v e r s e p r e g n a n c y outcomes w i t h c h e m i c a l e v i d e n c e o f e x p o s u r e . A t p r e s e n t , t h e r e was no d i r e c t evidence o f c a u s e - e f f e c t r e l a t i o n s h i p s w i t h c h e m i c a l s from the Canal." The C o m m i s s i o n a l s o c o n c l u d e d t h a t " c o m p r e h e n s i v e s t u d i e s o f three households w i t h unusually adverse reproductive h i s t o r i e s d i d not produce e v i d e n c e o f u n u s u a l r i s k o f c h e m i c a l exposure." The s t u d i e s a l s o c o n c l u d e d t h a t : " B l o o d t e s t i n g , w h i c h was d e s i g n e d t o s c r e e n f o r l i v e r a n d k i d n e y a b n o r m a l i t i e s , l e u k e m i a and b l o o d d i s e a s e s , showed no patterns o fexcess abnormality."

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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"None had c l i n i c a l e v i d e n c e o f l i v e r d i s e a s e . " "Computer a n a l y s e s o f t h e 22-page h e a l t h q u e s t i o n n a i r e , w h i c h e l i c i t e d i n f o r m a t i o n on some 150 d i f f e r e n t d i s e a s e s o r symptoms, p r o d u c e d no e v i d e n c e o f u n u s u a l p a t t e r n s o f i l l n e s s or other disorders. C a n c e r i n c i d e n c e was w i t h i n n o r m a l l i m i t s for this population." A t t e m p t s t o d e t e r m i n e t h e b a s i s f o r EPA d e c i s i o n s t o r e l o c a t e t h i s m a s s i v e g r o u p was u n a v a i l i n g . Congressman J o h n J . L a F a l c e ( D e m o c r a t , 3 6 t h D i s t r i c t , New Y o r k ) r e p r e s e n t i n g t h e Love C a n a l a r e a , a s k e d f o r t h e d a t a b a s e j u s t i f y i n g t h e d e c i s i o n and was t o l d i t was p a r t o f m a t e r i a l b e i n g u s e d i n p e n d i n g litigation. I n a l e t t e r t o P r e s i d e n t C a r t e r d a t e d J u n e 20, 1980, Congressman L a F a l c e s t a t e d " I f i n d no j u s t i f i c a t i o n whatsoever f o r making broad p o l i c y judgments — s u c h as t h e one h e r e t o recommend t e m p o r a r y r e l o c a t i o n o f 2,000 p e o p l e — based on i n f o r m a t i o n d e v e l o p e t h e n r e f u s i n g t o make whose l i v e s a r e d e v a s t a t e d by i t , and t o p u b l i c o f f i c i a l s who must make p u b l i c p o l i c y j u d g m e n t s h o p e f u l l y b a s e d on f a c t r a t h e r than surmise." Congressman L a F a l c e a l s o s u m m a r i z e d c l e a r l y t h e p o l i c y i s s u e s i n v o l v e d w i t h Love C a n a l i n h i s l e t t e r to P r e s i d e n t C a r t e r o f J u n e 20, 1980: The L o v e C a n a l i s a u n i q u e s i t u a t i o n . No h e a l t h a u t h o r i t i e s a t any l e v e l o f government h a v e e v e r c o n d u c t e d comprehensive h e a l t h t e s t s i n accepta b l e s c i e n t i f i c manner, d e s p i t e my r e p e a t e d c a l l f o r them. Some r e s i dents of the neighborhood b e l i e v e t h a t they s u f f e r from very s e r i o u s h e a l t h p r o b l e m s and t h a t t h e c a u s e i s t h e i r exposure to t o x i c chemicals. O t h e r s b e l i e v e t h a t t h e r e i s no more r i s k i n t h e a r e a t h a n i n many o t h e r urban environments. S t i l l others who do n o t know what t o t h i n k and have been s u f f e r i n g t e r r i b l e m e n t a l a n g u i s h f o r the p a s t t h r e e y e a r s . The one t h i n g t h e s e t h r e e g r o u p s do h a v e i n common, h o w e v e r , i s a l a c k o f i n f o r m a t i o n thanks i n p a r t to the a t t i t u d e of the U n i t e d S t a t e s Department o f J u s t i c e . A w h o l e n e i g h b o r hood i s s t i g m a t i z e d t o t h e p o i n t t h a t the property there i s l i t e r a l l y valueless. The p e o p l e who l i v e t h e r e a r e f r i g h t e n e d beyond b e l i e f and an arrogant o f f i c i a l i n the J u s t i c e D e p a r t m e n t s a y s t h e y c a n n o t even be t o l d why t h i s has been done.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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The d a t a b a s e was n o t f o r t h c o m i n g t o Congressman L a F a l c e o r t o anyone e l s e . Some c y n i c s m i g h t a r g u e t h a t p e r h a p s t h i s c a m p a i g n was l i n k e d t o t h e n p e n d i n g A d m i n i s t r a t i o n e f f o r t s t o p a s s S u p e r f u n d . W h a t e v e r t h e b a s i s , a s t h e New Y o r k b l u e r i b b o n p a n e l c o n c l u d e d i n O c t o b e r , 1980, "much o f t h e a n x i e t y c a u s e d f o r t h e Love C a n a l r e s i d e n t s m i g h t w e l l h a v e been a v e r t e d i f a s i n g l e F e d e r a l - S t a t e g r o u p had e v o l v e d e a r l y i n the h i s t o r y o f t h e s i t u a t i o n and t h a t p u b l i c p r o n o u n c e m e n t s were made o n l y b y t h i s g r o u p and l i m i t e d t o t h e e x a c t i t u d e s p e r m i t t e d b y t h e c u r r e n t s t a t e o f s c i e n t i f i c k n o w l e d g e . The s c i e n t i f i c e v i d e n c e , i n c o m p l e t e t h o u g h i t i s , r e v e a l s no s t a t e o f p o p u l a t i o n damage j u s t i f y i n g t h e t e r m 'imminent p e r i l a n d p r o f o u n d and d e v a s t a t i n g e f f e c t s . " A f t e r a l e n g t h y r e v i e w o f how t h e Love C a n a l s i t u a t i o n was h a n d l e d b y t h e v a r i o u s g o v e r n m e n t a l a g e n c i e s , t h e P a n e l members concluded that: "...The r e c o r c l e a r l y that an a r t i c u l a t e d and c o o r d i n a t e d F e d e r a l and S t a t e a p p r o a c h was n o t a c h i e v e d and has n o t been a c h i e v e d t o d a t e . . . . There d i d n o t emerge a t any p o i n t i n the p a s t two y e a r s a n y t h i n g l i k e a m a s t e r p l a n f o r a s s e m b l i n g the k i n d s o f i n f o r m a t i o n r e q u i r e d f o r a n a l y s i n g and comprehending the problem...because o f t h i s a m b i g u i t y , t h e p e o p l e most d i r e c t l y a f f e c t e d by t h e c o n d i t i o n s a t L o v e C a n a l have been s u b j e c t e d t o more t h a n two y e a r s o f the most i n t e n s e a n x i e t y and f e a r . I n t h e absence o f c l e a n - c u t , a u t h o r i t a t i v e a n s w e r s , many o f t h e r e s i d e n t s have come t o b e l i e v e t h a t t h e i r h e a l t h i s i n f a c t i r r e v e r s i b l y damaged, t h a t they are a t f u t u r e r i s k o f cancer, congenital malformations i n t h e i r o f f s p r i n g , and a n i n c r e a s e d i n c i d e n c e o f m i s c a r r i a g e s and a b o r t i o n s . " As f o r t h e s t u d i e s t h e P a n e l r e p o r t i n d i c a t e d " . . . t h e p u b l i c a t i o n o f s t u d i e s o n h e a l t h e f f e c t s and s u b s e q u e n t c r i t i c i s m s o f t h e s e s t u d i e s i n t h e m e d i a have c r e a t e d more u n c e r t a i n t y than understanding on p o t e n t i a l h e a l t h problems f o r both t h e p u b l i c and government o f f i c i a l s . . . T h e i n a d e q u a t e c o o r d i n a t i o n o f s t u d y d e s i g n s and p r o c e d u r e s t o i n s u r e m e a n i n g f u l f i n d i n g s c o n c e r n i n g h e a l t h e f f e c t s has e x a c e r b a t e d the p r o b l e m s f a c e d by d e c i s i o n makers i n r e s p o n d i n g t o t h i s s i t u a t i o n . " 1

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F i n a l l y , a s t o w h e t h e r t h e r e were any a c u t e o r c h r o n i c h e a l t h problems from exposure t o the c h e m i c a l s i n the Love C a n a l , the R e p o r t c o n c l u d e d :

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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I t i s c l e a r enough f r o m t h e a v a i l a b l e d a t a t h a t no a c u t e c a s e s o f i n t o x i c a t i o n by c h e m i c a l p o l l u t a n t s have been o b s e r v e d w i t h i n any p a r t o f t h e L o v e C a n a l community, w e t o r 'dry. That i s , no c l u s t e r s o f c a s e s of acute l i v e r d i s e a s e , o r kidney d i s e a s e , o r pulmonary m a n i f e s t a t i o n s , o r h e m o l y t i c anemia o r a g r a n u l o c y t o s i s , and c e r t a i n l y no p e r i p h e r a l o r c e n t r a l n e r v o u s s y s t e m syndromes. W h a t e v e r e l s e may be g o i n g o n , t h e r e has n o t b e e n a s u f f i c i e n t c o n c e n t r a t i o n of t o x i c m a t e r i a l t o produce overt i l l n e s s a t t r i b u t a b l e to poisoning. T

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Thi outset. As a r e s u l t o f t h i s r e v i e w , t h e P a n e l has c o n c l u d e d t h a t t h e r e h a s b e e n no d e m o n s t r a t i o n o f a c u t e h e a l t h e f f e c t s l i n k e d t o exposure t o h a z a r d ous w a s t e s a t t h e L o v e C a n a l s i t e . The P a n e l h a s a l s o c o n c l u d e d t h a t c h r o n i c e f f e c t s of hazardous waste e x p o s u r e a t L o v e C a n a l have n e i t h e r been e s t a b l i s h e d o r r u l e d o u t y e t , i n a s c i e n t i f i c a l l y r i g o r o u s manner. The s t u d i e s c o n d u c t e d i n t h e p a s t two y e a r s have b e e n i n c o n c l u s i v e i n d e m o n s t r a t i n g l o n g term h e a l t h e f f e c t s due t o h a z a r d o u s w a s t e exposure. As t h i s t a l k i s w r i t t e n , we a r e s t i l l w a i t i n g f o r a f i n a l EPA r e p o r t on t h e h e a l t h i m p a c t s o f L o v e C a n a l . A f t e r r e v i e w o f t h e f a c t chronology i n Love C a n a l i t i s easy t o s e e t h a t t h e f a c t o r s f o r e f f e c t i v e management o f h a z a r d o u s w a s t e d i s p o s a l s i t e s were s i m p l y n o t u t i l i z e d o r a v a i l a b l e i n L o v e C a n a l . These f a c t o r s a g a i n a r e : a r e s p o n s i b l e a n a l y t i c a l b a s e t o a c c u r a t e l y measure l e v e l s o f p o t e n t i a l o r a c t u a l human e x p o s u r e w h i c h i n c l u d e s comparison w i t h other r e l e v a n t areas a c o m p a r a t i v e b a s e o f t o x i c o l o g i c a l and e p i d e m i o logical information an a s s e s s m e n t o f r i s k b a s e d on t h e s e two f a c t b a s e s an i n d e p e n d e n t c h e c k by q u a l i f i e d e x p e r t s s e p a r a t e d f r o m p o l i t i c a l and e m o t i o n a l f a c t o r s L o v e C a n a l i s t h e b e s t o r w o r s t example o f t h e f a i l u r e t o u s e common s e n s e i n d e a l i n g w i t h a p o t e n t i a l a l l e g e d r i s k t o human h e a l t h . But a n o t h e r e x a m p l e , p a r t i c u l a r l y o f p s y c h o -

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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l o g i c a l i m p a c t , i s d e t a i l e d i n a n a r t i c l e e n t i t l e d The Dump T h a t Wasn't T h e r e , " 215 S c i e n c e , F e b r u a r y 5, 1982, a t p. 6 4 5 , c i t e d a s a n example o f t h e p e r i l s o f r e l y i n g o n r e s i d e n t s r e p o r t i n g an i n c r e a s e d i n c i d e n c e o f h e a l t h e f f e c t s . The f a c t s as r e p o r t e d i n S c i e n c e a r e a s f o l l o w s : A resident i n a blue c o l l a r r e s i d e n t i a l n e i g h b o r h o o d i n Memphis c a l l e d t h e l o c a l h e a l t h d e p a r t m e n t i n 1976 t o c o m p l a i n o f r a s h e s and o t h e r m i n o r i l l n e s s e s , a l l e g i n g t h a t she and h e r f a m i l y were b e i n g p o i s o n e d by t o x i c c h e m i c a l s i n t h e e n v i r o n m e n t . I n v e s t i g a t i o n o f her home and y a r d d i s c l o s e d o n l y t r a c e c o n c e n t r a t i o n s o f c h l o r d a n e and o t h e r p e s t i c i d e s t h a t a r e u s e d i n Memphis t o c o n t r o l t e r m i t e s and m o s q u i t o s . The same woman c a l l e d a g a i n i n 1977 and 1978 w i t h t h e same c o m p l a i n t s a n d same r e s u l t s . By t h e summer o f 1979, o t h e r r e s i d e n t s i n t h e n e i g h b o r h o o d had begun t o c o m p l a i n o f i n c r e a s e d i n c i d e n c e o f r a s h e s , h e a d aches, u r i n a r y problems by t h e a l l e g a t i o n s o t h a t he "knew" t h e l o c a t i o n o f a c h e m i c a l w a s t e dump i n t h e area. By t h e f o l l o w i n g A p r i l , t h e D i r e c t o r o f t h e h e a l t h d e p a r t m e n t i n d i c a t e d t h a t t h e r e was a " h i g h l y c h a r g e d a t m o s phere, v i r t u a l l y i d e n t i c a l t o t h a t a t Love C a n a l . " The c i t i z e n s " p a n i c k e d " and t h e r e were p i c k e t i n g and emotional meetings. T h e r e was t a l k o f e v a c u a t i n g t h e a r e a a n d l o c a l p o l i t i c a l a c t i v i s t s pressed f o r immediate a c t i o n i n the area. T h e r e were even C o n g r e s s i o n a l h e a r i n g s . Extensive i n v e s t i g a t i o n b y EPA f o u n d " a b s o l u t e l y n o t h i n g h i g h e r t h a n t h e background l e v e l s o f p e s t i c i d e s . " A respected p r o f e s s o r a t J o h n s H o p k i n s U n i v e r s i t y went t h r o u g h o l d r e c o r d s and c o n d u c t e d o t h e r s t u d i e s w i t h no i n d i c a t i o n o f t h e s o u r c e . The U.S. C e n t e r f o r D i s e a s e C o n t r o l c o n d u c t e d a d o o r - t o d o o r s u r v e y o f some 300 homes a s k i n g a b o u t e f f e c t s and e x a m i n e d p h y s i c i a n s ' r e c o r d s . The s u r v e y " d i d n o t p r o d u c e any e v i d e n c e of t o x i c i l l n e s s o r severe h e a l t h e f f e c t s . " However, t h e s u r v e y d i d show a s l i g h t i n c r e a s e d i n c i d e n c e o f h e a d a c h e s a n d s k i n r a s h e s , b u t t h e c o n c l u s i o n was t h a t i t was " u n l i k e l y t h e y were c h e m i c a l l y c a u s e d . " One man f o u n d t o have heavy m e t a l p o i s o n i n g w o r k e d i n a f o u n d r y and one o f t h e c h i l d r e n o f t h e woman m a k i n g t h e o r i g i n a l c o m p l a i n t was f o u n d t o have h i v e s . I t t o o k 14 months f o r t h e C e n t e r f o r D i s e a s e C o n t r o l t o p u b l i s h a s t u d y and b y t h a t t i m e , a c c o r d i n g t o t h e head o f t h e l o c a l h e a l t h d e p a r t m e n t , "nobody b e l i e v e d any a g e n c y . " A b o u t t h e same t i m e t h e l o c a l a u t h o r i t i e s d i d become aware o f a l o c a l dump s i t e , b u t i t was some 3 t o 4 m i l e s away f r o m t h e n e i g h b o r hood and s e p a r a t e d b y s e v e r a l p h y s i c a l b a r r i e r s s o " t h a t t h e r e i s no c h a n c e o f a n y c h e m i c a l s f r o m i t h a v i n g r e a c h e d F r a y z e r [the l o c a l neighborhood]." T h e r e a r e s t i l l a s m a l l number o f p e o p l e i n t h e n e i g h b o r hood who b e l i e v e t h e y have u n u s u a l h e a l t h p r o b l e m s , b u t by now t h e u p r o a r has d i e d down. The a r t i c l e c o n c l u d e s w i t h t h e comment t h a t " t h e s p e c t e r o f t h i s g h o s t dump w i l l c o n t i n u e t o

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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haunt e p i d e m i o l o g i s t s c o n f r o n t e d w i t h o t h e r s e l f - r e p o r t e d increases i n i l l n e s s . " How c a n we p r e v e n t t h e c r y i n g o f " w o l f " and t h e u n n e c e s s a r y p s y c h o l o g i c a l d i s t r e s s c a u s e d by government a c t i o n s a t L o v e C a n a l and t h e "phantom dump?" These p r o b l e m s a r e r e a l and a r e d e s c r i b e d i n d e t a i l i n L o v e C a n a l R e s i d e n t s Under S t r e s s , 208 S c i e n c e , J u n e 13, 1980 a t p. 1242, w h i c h g r a p h i c a l l y d i s c u s s e s the p s y c h o l o g i c a l impacts of the u n c e r t a i n t y c r e a t e d by t h e muddled g o v e r n m e n t a l r e s p o n s e . P e r h a p s t h e b e s t way i s f o r f e d e r a l and s t a t e g o v e r n m e n t a l a g e n c i e s t o have a p e e r p a n e l a v a i l a b l e on c a l l when t h e r e i s an i n c i d e n t , t o r e v i e w d a t a b e f o r e i t i s r e l e a s e d . H a v i n g t h e p a n e l a v a i l a b l e w i l l save v a l u a b l e time i n t h e event t h a t t h e r e i s an i m m i n e n t d a n g e r . Such p a n e l s c a n a c t q u i c k l y , a s , f o r e x a m p l e , i n t h e r e v i e w o f t h e EPA chromosome s t u d y i n a t h r e e day p e r i o d . U n l e s s t h mandate i n r e g u l a t i o n a v a i l a b l e , we c a n n o t e v e r e x p e c t t o e f f e c t i v e l y manage h a z a r d ous w a s t e i n c i d e n t s . The d e c i s i o n s i n t h i s a r e a a r e t o o i m p o r t a n t t o a l l o w an a g e n c y u n d e r p o l i t i c a l and e m o t i o n a l s t r e s s t o make t h i s d e c i s i o n a l o n e . C o n f i d e n c e i n government i s s i g n i f i c a n t l y e r o d e d when t h e d a t a a r e n o t a v a i l a b l e o r l a c k a scientific basis. C o n f i d e n c e i n i n d u s t r y becomes n o n e x i s t e n t when s u c h a c t i o n i s t a k e n . L o v e C a n a l h a s become a g e n e r i c t e r m f o r h e a l t h e f f e c t s on i n d i v i d u a l s and i r r e s p o n s i b i l i t y o f c o r p o r a t i o n s , a l t h o u g h i r o n i c a l l y t h e T a s k F o r c e on RCRA o f t h e A m e r i c a n I n s t i t u t e o f C h e m i c a l E n g i n e e r s c o n c l u d e d t h a t " t h e d e s i g n o f t h e L o v e C a n a l s i t e was w e l l w i t h i n t h e s t a n d a r d s o f RCRA," l o n g b e f o r e t h a t s t a t u t e was p r o m u l g a t e d . The f a c t s i n d i c a t e t h a t t h e c h a r a c t e r i z a t i o n s a r e u n f a i r , b u t t h e p u b l i c remembers t h e c o n c e r n s r a i s e d by t h e a g e n c i e s and t h e p r e s s and n o t t h e s c i e n t i f i c b a s e . Unfair stigmatizat i o n o f companies i s wrong, b u t t r a u m a t i z a t i o n s o f whole l o c a l populations without a proper b a s i s i s r e p r e h e n s i b l e . R E C E I V E D June 16,

1982.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

5 An Industry's Guidelines for Risk Assessment RICHARD H . DREITH Shell Oil Company, Houston, T X 77210

In the absence of a consensus on a b s o l u t e limits of risk, it i s u s e f u assessment framewor response resource allocation. A f o u r - s t e p process is i n use at S h e l l to e v a l u a t e risks and d e f i n e a p p r o p r i a t e responses. The steps a r e : (1) Hazard Identification, (2) Hazard E v a l u a t i o n , (3) R i s k E v a l u a t i o n , and (4) R i s k Response. The first three steps amount to making a "risk assessment," and the f o u r t h step adds a response definition. A risk classification system s e t t i n g h i g h , low and insignificant categories for risk reflecting unacceptable, v a r i o u s l y a c c e p t a b l e and a c c e p t a b l e r e g i o n s r e s p e c tively are d e f i n e d , and companion l e v e l s of response a c t i o n are p r e s e n t e d . An overview of a site evaluation experience in California i s o u t l i n e d .

R i s k assessment i s a d i f f i c u l t problem area b e i n g addressed by i n d u s t r y and r e g u l a t o r y a g e n c i e s t o d a y . I h a v e f o u n d i n my p r o f e s s i o n a l e x p e r i e n c e i n t h e o i l and c h e m i c a l i n d u s t r y , t h a t when f a c e d w i t h s o l v i n g d i f f i c u l t p r o b l e m s , s o l u t i o n s g e n e r a l l y r e s u l t e d by t a k i n g l o g i c a l and d i s c i p l i n e d a p p r o a c h e s t o r e s o l v e u n c e r t a i n t i e s . We a t S h e l l h a v e d e v e l o p e d and a r e u s i n g g u i d e l i n e s f o r r i s k assessment which a r e a l l o w i n g us t o analyze r i s k s and i d e n t i f y r e a s o n a b l e r e s p o n s e s . The u s e o f t h e s e s y s t e m a t i c p r o c e d u r e s have i m p r o v e d o u r c o n f i d e n c e i n t h e d e c i s i o n s we must make. I n r e s p o n d i n g t o r i s k s i t u a t i o n s , o u r c o n f i d e n c e i s b u i l t on k n o w i n g t h a t t h e r e s p o n s e s a r e d i r e c t i o n a l l y c o r r e c t and a r e a c h i e v i n g our o v e r a l l goal t o reduce r i s k . Of l a t e , I have b e e n d i s a p p o i n t e d b y t h e c o n s e n s u s o p i n i o n which appears t o be growing r e g a r d i n g d e a l i n g w i t h r i s k assessments. From i n f o r m a t i o n i n t h e m e d i a and d i s c u s s i o n s w i t h c o n t e m p o r a r i e s and a g e n c y r e p r e s e n t a t i v e s , I d e t e c t a n o p i n i o n t h a t suggests s o c i e t y i s not ready t o deal s y s t e m a t i c a l l y w i t h 0097-6156/82/0204-0045 $06.00/0 © 1982 American Chemical Society

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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assessing risk. I n my v i e w , t h o s e who s u p p o r t t h i s c l a i m a r e a s r e m i s s a t t h a t e x t r e m e a s t h o s e who w o u l d now p l a c e t o t a l f a i t h i n s e e m i n g l y h i g h l y p r e c i s e m e t h o d o l o g i e s f o r e x t r a p o l a t i o n s and r i s k a s s e s s m e n t s . A d d i t i o n a l l y , t h e o p i n i o n f o l l o w s t h a t we a r e n o t ready t o t r a n s l a t e c u r r e n t r i s k assessment u n d e r s t a n d i n g i n t o r e g u l a t o r y programs b e i n g implemented. I d o n ' t t h i n k we a t S h e l l a g r e e w i t h e i t h e r o p i n i o n , o r a r e a p a r t o f any c o n s e n s u s e m b r a c i n g t h e s e o p i n i o n s . We w i l l b e d i s a p p o i n t e d , I'm s u r e , i f t h e i m p l e m e n t a t i o n o f e i t h e r t h e R e s o u r c e C o n s e r v a t i o n and R e c o v e r y A c t (RCRA) o r t h e C o m p r e h e n s i v e E n v i r o n m e n t a l R e s p o n s e C o m p e n s a t i o n and L i a b i l i t y A c t (CERCLA) p r o g r a m s p r o c e e d w i t h o u t t h e r e b e i n g i n c o r p o r a t e d a t l e a s t some r e g u l a t o r y allowances f o r assessing a c t u a l r i s k s . The r i s k s p o s e d b y v a r i o u s h a z a r d o u s w a s t e h a n d l i n g a c t i v i t i e s must be a s s e s s e d when j u d g ments on t h e i r a c c e p t a b i l i t made h durin th permit t i n g process. I am s u g g e s t i n r i s k s e x i s t s , and i t s h o u l t o r y r e q u i r e m e n t s , (2) when e s t a b l i s h i n g f a c i l i t y p e r f o r m a n c e s t a n d a r d s , o r ( 3 ) when d e f i n i n g r e m e d i a l a c t i v i t i e s . We f u l l y r e c o g n i z e t h a t many a r e a s o f u n c e r t a i n t y a r e c o n f r o n t e d when c o n d u c t i n g r i s k a s s e s s m e n t s . These i n c l u d e t h e l a c k of g e n e r a l l y accepted s p e c i f i c assessment techniques. Furthermore, e v e n when r i s k i s a s s e s s e d t h e r e i s a l a c k o f a c o n s e n s u s on the absolute l i m i t s of acceptable r i s k s . We do f e e l , h o w e v e r , t h a t t h e r e a r e s y s t e m a t i c a p p r o a c h e s t h a t c a n and a r e b e i n g u s e d and, a t t h e minimum, t h e y a r e d i r e c t i o n a l l y c o r r e c t and c a n s e r v e as a c o n c e p t u a l f r a m e w o r k f o r r e g u l a t o r y p r o g r a m d e v e l o p m e n t . S h e l l R i s k Assessment Procedure I w i l l o u t l i n e very b r i e f l y f o r you the g u i d e l i n e s , process and p r o c e d u r e s u s e d a t S h e l l f o r r i s k a s s e s s m e n t a n d r i s k r e s p o n s e ( 1 ) , ( 2 ) . I w i l l f o c u s my comments on how we a r e b e g i n n i n g to d e a l , f o r example, w i t h d e c i s i o n s c o n c e r n i n g t h e a c c e p t a b i l i t y o f o p e r a t i n g e x i s t i n g h a z a r d o u s w a s t e d i s p o s a l f a c i l i t i e s o r when c o n s i d e r i n g new w a s t e h a n d l i n g f a c i l i t i e s . The s t e p - w i s e e v a l u a t i o n and d e c i s i o n p r o c e s s c a n a l s o be u s e d i n a s s e s s i n g t h e e n v i r o n m e n t a l r i s k s p o s e d b y abandoned hazardous waste d i s p o s a l s i t e s . I w i l l a l s o b r i e f l y describe our e x p e r i e n c e w i t h a s i t e i n a s o u t h e r n C a l i f o r n i a community. Our R i s k A s s e s s m e n t P r o c e d u r e h a s grown o u t o f a c o n t i n u i n g n e e d t o d e a l w i t h b a l a n c i n g a l l t h e a s p e c t s o f h e a l t h and environmental r i s k s w i t h a l l other p e r t i n e n t elements i n our o i l and c h e m i c a l b u s i n e s s a c t i v i t i e s . The d e c i s i o n s we must make to d e a l a p p r o p r i a t e l y w i t h r i s k a r e n e c e s s a r i l y an i m p o r t a n t c o n s i d e r a t i o n i n pursuing our o v e r a l l business plan. I n many c a s e s , we must t a k e a c t i o n and make d e c i s i o n s p r i o r to r e g u l a t i o n s being issued which deal w i t h r i s k i n s p e c i f i c areas. By n e c e s s i t y t h e n , we need and u s e a s y s t e m t h a t r e f l e c t s o u r c o r p o r a t e e n v i r o n m e n t a l g o a l s and a l s o a l l o w s g u i d i n g t h e

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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a l l o c a t i o n of the l i m i t e d resources a v a i l a b l e t o reach those goals. In a s e n s e , we c a n s a y we have d e v e l o p e d a s y s t e m t o a s s e s s e n v i r o n m e n t a l r i s k s i t u a t i o n s and a r e r e s p o n d i n g t o t h o s e a s s e s s ments w i t h d e c i s i o n s r e a c h e d i n a d e l i b e r a t e and d i s c i p l i n e d manner. The c o n f i d e n c e we have i n t h e s y s t e m i s b u i l t on t h e p r e m i s e t h a t we know i t i s d i r e c t i o n a l l y c o r r e c t w i t h i t s o v e r a l l o b j e c t i v e being t o reduce r i s k s . Moreover, t h e response d e c i s i o n s c a l l e d f o r i n t h e process r e s u l t from e v a l u a t i n g a l l t h e a v a i l a b l e s c i e n t i f i c information along with a l l the pertinent v a l u e s and j u d g m e n t s t h a t c a n be b r o u g h t t o b e a r . O v e r a l l , t h e major premise f o r our approach i s a d i r e c t i o n a l o r i e n t a t i o n t o w a r d r i s k r e d u c t i o n . The e v a l u a t i o n p r o c e d u r e used f o l l o w s a f o u r - s t e p p r o c e s s w h i c h c o n s i d e r s f i r s t Hazard I d e n t i f i c a t i o n ; second Hazard E v a l u a t i o n ; t h i r d Risk E v a l u a t i o n ; and f o u r t h standing of terms, t h e s t e p s c a n be c o n s i d e r e d a s what i s commonly r e f e r r e d t o as m a k i n g a " R i s k A s s e s s m e n t . " The f o u r t h s t e p , R i s k R e s p o n s e , n e c e s s a r i l y must f o l l o w when t h e p r o c e s s i s used t o make p r a c t i c a l d e c i s i o n s . I w i l l now g i v e an o v e r v i e w d i s c u s s i o n i d e n t i f y i n g t h e g e n e r a l i n f o r m a t i o n needs and t h e s p e c i f i c d e c i s i o n s c a l l e d f o r a t e a c h s t e p . I w i l l u s e a s t h e example c a s e , e v a l u a t i n g a h a z a r d o u s waste d i s p o s a l s i t e . A l s o , I w i l l d i s c u s s the a p p l i c a t i o n of the p r o c e s s t o an a c t u a l s i t e b e i n g e v a l u a t e d i n C a l i f o r n i a . Hazard

Identification

As i s t y p i c a l i n r e g u l a t o r y m a t t e r s , u n d e r s t a n d i n g t h e d e f i n i t i o n s o f t h e terms used i s v e r y i m p o r t a n t . F i r s t , i n t h e b r o a d e s t s e n s e , h a z a r d means t h e p o t e n t i a l t o do harm, o r i n o t h e r w o r d s , t h e p o t e n t i a l t o c a u s e an a d v e r s e e f f e c t . In a waste d i s p o s a l s i t e e v a l u a t i o n , t h e hazard i d e n t i f i c a t i o n s t e p w i l l i n v o l v e c o l l e c t i n g and v a l i d a t i n g a l l r e c o r d e d and o t h e r i n f o r m a t i o n on t h e n a t u r e and p r o p e r t i e s o f t h e w a s t e s actually i n a site. The p u r p o s e i s t o d e t e r m i n e w h e t h e r a h a z a r d ous s i t u a t i o n a c t u a l l y e x i s t s . S t a t e d s i m p l y , jLs t h e r e a. p o t e n t i a l f o r harm t o h e a l t h and t h e e n v i r o n m e n t when c o n s i d e r i n g t h e materials present? The t y p e o f d a t a g a t h e r e d w i l l i n c l u d e a l l p e r t i n e n t i n f o r m a t i o n on (1) t h e i n v e n t o r y o f t h e w a s t e s d i s p o s e d o f a t t h e s i t e , (2) t h e c o m p o s i t i o n o f t h o s e w a s t e s , ( 3 ) t h e p h y s i c a l and c h e m i c a l p r o p e r t i e s s u c h a s p e r s i s t e n c e o f compounds and t h e i r s o l u b i l i t i e s , (4) t h e b i o l o g i c a l p r o p e r t i e s s u c h a s t o x i c i t y , and (5) t h e p o t e n t i a l i n t e r a c t i o n o f w a s t e s and d e g r a d a t i o n p r o d u c t s . The d e c i s i o n c a l l e d f o r a t t h i s p o i n t i n t h e p r o c e s s c e n t e r s on c o n f i r m i n g t h a t , f r o m t h e q u a l i t a t i v e d a t a g a t h e r e d , a p o t e n t i a l f o r an adverse e f f e c t has o r has n o t been i d e n t i f i e d . I f no hazard e x i s t s , f u r t h e r a c t i o n i s not warranted. I f the potential f o r an a d v e r s e e f f e c t i s e v i d e n t , t h e p r o c e s s r e q u i r e s p r o c e e d i n g t o t h e n e x t s t e p - H a z a rr d Evaluât iiocn . . -

American Cnemfca? Society Library 1155 16th St. N. Sites; w. Long, F., et al.; In Risk Assessment at Hazardous Waste ACS Symposium Series; American Chemical Washington, DC, 1982. Washington, D. C. Society: 20038

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Evaluation

The h a z a r d e v a l u a t i o n s t e p i n v o l v e s d e t e r m i n i n g t h e e x t e n t or scope o f t h e p o t e n t i a l adverse e f f e c t s from t h e hazards i d e n t i f i e d i n s t e p one. The e v a l u a t i o n e f f o r t now p r o g r e s s e s t o i n c l u d e a n a l y z i n g and d e s c r i b i n g b o t h q u a l i t a t i v e l y and q u a n t i t a t i v e l y t h e c h a r a c t e r i s t i c s w h i c h might cause t h e wastes t o be h a z a r d o u s and t o p r o v i d i n g t h e means f o r d e t e r m i n i n g i n s t e p t h r e e , t h e r i s k s i n v o l v e d under t h e d i s p o s a l c i r c u m s t a n c e s s p e c i f i c to the s i t e being studied. These means may i n c l u d e g a t h e r i n g p e r t i n e n t i n f o r m a t i o n f r o m l a b o r a t o r y and o t h e r s t u d i e s on t h e t o x i c o l o g i c a l p r o p e r t i e s of the array of c o n s t i t u e n t s i n the s i t e . A l s o p e r t i n e n t would be t h e range o f r e s p o n s e s t o t h o s e c o n s t i t u e n t s u n d e r t h e v a r i o u s s t a t e d , n o t a c t u a l , l e v e l s and t y p e s o f exposures along w i t h reviewing i n t e r - s p e c i e s t r a n s l a t i o n r e l a t i o n s h i p s and t h e means t o W i t h t h e f o c u s on i n t h e s i t e i n v e n t o r y , a p p r o p r i a t e f i e l d s a m p l i n g and a n a l y s i s must be u n d e r t a k e n t o v e r i f y t h a t t h e i d e n t i f i e d h a z a r d s a c t u a l l y exist. I f a h a z a r d h a s b e e n i d e n t i f i e d and t h e p o t e n t i a l f o r causing adverse e f f e c t s confirmed, a f t e r considering both the q u a l i t a t i v e and q u a n t i t a t i v e dimensions o f t h e s i t u a t i o n , t h e process r e q u i r e s proceeding to the next step - Risk E v a l u a t i o n . Risk

Evaluation

R i s k e v a l u a t i o n i n t h e a s s e s s m e n t p r o c e s s f o c u s e s on w e i g h i n g t h e h e a l t h and e n v i r o n m e n t a l t h r e a t s p o s e d b y a n i d e n t i f i e d h a z ard. F i r s t , t h e p o s s i b i l i t y and p r o b a b i l i t y t h a t a p e r s o n w i l l a c t u a l l y e x p e r i e n c e an adverse e f f e c t as a r e s u l t o f t h e e x i s t e n c e o f t h e e n v i r o n m e n t a l h a z a r d and e x p o s u r e t o i t must b e w e i g h e d ; and, s e c o n d l y , t h e number o f p e r s o n s who m i g h t be e x p o s e d must be considered. In t h e s t e p w i s e p r o c e s s , t h e r i s k e v a l u a t i o n combines t h e r e s u l t s o f t h e s e c o n d s t e p , h a z a r d e v a l u a t i o n , w i t h any i n f o r m a t i o n on a c t u a l e x p o s u r e p o s s i b i l i t i e s , i n c l u d i n g e v a l u a t i n g e x p o s u r e s o u r c e s , l e v e l s , f r e q u e n c i e s , t y p e s and r o u t e s . The a s s e s s ment e f f o r t i n v o l v e s i n t e r p r e t i n g t h e f i e l d v e r i f i e d d a t a f r o m t h e p e r s p e c t i v e o f d e t e r m i n i n g what t h e a c t u a l r i s k l e v e l t o humans and t h e e n v i r o n m e n t i s i n t h e r e a l w o r l d c i r c u m s t a n c e s p o s e d by the a c t i v i t y being evaluated. In t h e case o f a hazardous waste d i s p o s a l s i t e , the geoh y d r o l o g i c s e t t i n g c h a r a c t e r i s t i c s must now be c a r e f u l l y c o n s i d e r e d t o assess t h e e x i s t e n c e of subsurface exposure routes. A l s o , t h e p o t e n t i a l f o r e x p o s u r e f r o m a i r e m i s s i o n s and s u r f a c e r u n o f f must b e q u a n t i f i e d w h e r e p o s s i b l e . O v e r a l l , t h e s i g n i f i cant f a c t o r s would i n c l u d e : (1) e v a l u a t i n g t h e v o l a t i l i t y o f t h e w a s t e s w h i c h c o u l d l e a d t o s h o r t - and l o n g - t e r m e x p o s u r e t o a i r

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

5.

DREITH

An

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e m i s s i o n s , (2) c o n s i d e r i n g t h e l o n g - t e r m s o l u b i l i t y o f t h e w a s t e s i n w a t e r s f r o m e i t h e r r a i n f a l l o r s u r f a c e r u n o f f , (3) c o n s i d e r i n g t h e c o n t i n u i n g p o t e n t i a l f o r s u r f a c e w a t e r c o n t a c t , (4) r e v i e w i n g t h e r a i n f a l l r a t e s and r a i n f a l l f l o w p a t h s as t o t h e i r a b i l i t y t o s u p p o r t t h e i r c o n t r i b u t i o n t o c o n t i n u e d e x p o s u r e , (5) i d e n t i f y i n g t h e g r o u n d w a t e r c o n t a m i n a t i o n p o t e n t i a l and m i g r a t i o n p a t h s , (6) i d e n t i f y i n g g r o u n d w a t e r u s e s , and (7) a p p r a i s i n g p o p u l a t i o n e x p o s u r e by c o n s i d e r i n g p r o x i m i t y and number. I f t h e r i s k e v a l u a t i o n s t e p shows t h a t a s i g n i f i c a n t p o t e n t i a l f o r adverse e f f e c t s e x i s t s , the stepwise process c a l l s f o r d e v e l o p i n g an a p p r o p r i a t e r e s p o n s e . D e t e r m i n i n g t h e a p p r o p r i a t e ness of a response i m p l i e s having a b a s i s to vary the response. P r o v i d i n g t h a t b a s i s i s t h e end p r o d u c t o f t h e r i s k e v a l u a t i o n step. I t i n v o l v e s c l a s s i f y i n g t h e r i s k as b e i n g h i g h , low o r i n s i g n i f i c a n t so t h a t t h e a p p r o p r i a t e r e s p o n s e can be d e v e l o p e d Before d i s c u s s i n g emphasize t h a t the hazar r i s k e v a l u a t i o n s t e p s a r e p u r p o s e l y k e p t f r e e , as much as p o s s i b l e , of v a l u e judgments. Credible r i s k evaluations necessarily require u s i n g t h e b e s t s c i e n t i f i c i n p u t , t h e o r y , acumen and j u d g m e n t s . In t h e f o u r t h s t e p , v a l u e j u d g m e n t s come i n t o p l a y t o a s s i s t i n d e v e l o p i n g r i s k responses r e f l e c t i n g those s o c i e t a l judgments t h a t b e a r on t h e s i t u a t i o n b e i n g e v a l u a t e d . To c l a s s i f y r i s k s , a s y s t e m o r f r a m e w o r k f o r c l a s s i f i c a t i o n must be a g r e e d upon. I n a p e r f e c t w o r l d , a s o c i e t a l c o n s e n s u s on l e v e l s o f " r i s k a c c e p t a b i l i t y " w o u l d be a t hand and be s t r a i g h t f o r w a r d i n how i t w o u l d be a p p l i e d i n e a c h s i t u a t i o n b e i n g evaluated. However, i n t h e r e a l w o r l d t h e r e i s no c o n s e n s u s , and we c a n o n l y e v a l u a t e and t h e n d e f i n e t h e r a n g e s o f r i s k s p o s e d i n a c t u a l s i t u a t i o n s and t h e n j u d g e them f o r t h e i r a c c e p t a b i l i t y t o society. W i t h i n S h e l l , when t a k i n g a c t i o n s b e y o n d t h o s e r e q u i r e d by l a w , we use t h e c o n c e p t o f r i s k r e g i o n s o r r i s k c l a s s i f i c a t i o n s . The o b j e c t i v e o f our c l a s s i f i c a t i o n scheme i s t w o f o l d ; f i r s t , t o p r o v i d e guidance f o r the a l l o c a t i o n of resources such t h a t the most s e r i o u s r i s k s a r e h a n d l e d f i r s t ; and s e c o n d , t o i d e n t i f y t h o s e s i t u a t i o n s where a l l o c a t i n g r e s o u r c e s i s n o t w a r r a n t e d s i n c e t h e r i s k i s j u d g e d t o be i n s i g n i f i c a n t . Our s y s t e m , t h e r e f o r e , d i s t i n g u i s h e s t h r e e c l a s s i f i c a t i o n s o f risk: h i g h , low, and i n s i g n i f i c a n t . One m i g h t a r g u e t h a t a medium r i s k r e g i o n e x i s t s . A t t h i s t i m e , c o n s i d e r i n g a medium r i s k r e g i o n w o u l d o n l y add an u n r e a l i s t i c a u r a o f p r e c i s i o n t o t h e s y s t e m . We r e c o g n i z e d a t t h e o u t s e t t h a t t h e t o o l s a v a i l a b l e t o us i n our c l a s s i f i c a t i o n scheme a r e b l u n t . D e f i n i t i o n o f t h e b o u n d a r i e s between t h e r i s k r e g i o n s can be p r e c i s e by c h o i c e ; however, t h e r e a r e no e s t a b l i s h e d c r i t e r i a f o r b o u n d a r y s e t t i n g and, a t t h i s t i m e , o n l y g u i d e l i n e s f o r b o u n d a r y s e l e c t i o n can be o f f e r e d (1). The r a n g e o f c h o i c e s m i g h t i n c l u d e (1) r e a s o n a b l e p e r f o r m a n c e g o a l s f o r b e s t t e c h n o l o g y c o n t r o l equipment when a c t u a l e x p o s u r e l e v e l s f r o m e x i s t i n g f a c i l i t i e s i s N

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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a s s e s s e d , (2) t h e f e a s i b i l i t y o f c o n t r o l l i n g e x p o s u r e s , and (3) a d e s i r a b l e i n d u s t r y or a c t i v i t y performance g o a l . W h i l e the framework f o r r i s k r e g i o n s i s p r e c i s e , the u n c e r t a i n t i e s emerge when r e a l w o r l d i m p r e c i s e e v a l u a t i o n s o f r i s k r e c o g n i z i n g t h e b l u n t n e s s o f o u r t o o l s - a r e measured by t h e p r e c i s e y a r d s t i c k s . N e v e r t h e l e s s , when c o n s i d e r i n g r i s k c l a s s i f i c a t i o n s f r o m a s o c i e t a l v i e w p o i n t , one c a n h a v e c o n f i d e n c e and l o g i c a l l y c l a s s i f y h i g h r i s k r e g i o n s as b e i n g r e g i o n s o f " u n a c c e p table risk." The l o w r i s k r e g i o n m i g h t s i m i l a r l y be l a b e l e d as " v a r i o u s l y a c c e p t a b l e " w i t h t h e t h i r d r e g i o n r e f e r r e d t o as "insignificant risk." C o n s i s t e n t w i t h t h a t c l a s s i f i c a t i o n scheme, one c o u l d d e f i n e a p a r a l l e l s e r i e s o f a p p r o p r i a t e r e s p o n s e s . R i s k Response R i s k response i n v o l v e responses i n c l u d e s makin r i s k s s o c i e t y t a k e s , i n c l u d i n g t h e i r v i e w on t h e s e r i o u s n e s s o f t h e r i s k and t h e p e r c e i v e d b e n e f i t s f r o m t a k i n g t h a t r i s k . From t h e p r o c e s s o f c o m b i n i n g t h e s c i e n t i f i c i n f o r m a t i o n a v a i l a b l e w i t h t h e p e r t i n e n t v a l u e j u d g m e n t s , d e c i s i o n s c a n be made as t o what a c t i o n s a r e r e q u i r e d and j u s t i f i e d a s a p p r o p r i a t e r e s p o n s e t o the r i s k posed. When a r i s k a s s e s s m e n t shows a " h i g h r i s k " s i t u a t i o n , this w o u l d be j u d g e d u n a c c e p t a b l e and r e q u i r e a r e s p o n s e t o a b a t e t h e r i s k and move i t downward t o w a r d t h e "low r i s k " o r " v a r i o u s l y acceptable" region. S i m i l a r l y , an " i n s i g n i f i c a n t r i s k " c l a s s i f i c a t i o n i s j u d g e d as d e f i n i n g t h o s e s i t u a t i o n s w h i c h do n o t j u s t i f y o r w a r r a n t t h e a l l o c a t i o n o f r e s o u r c e s f o r f u r t h e r r i s k r e d u c t i o n . I must emphas i z e at t h i s p o i n t t h a t the " i n s i g n i f i c a n t " c l a s s i f i c a t i o n i s not e q u i v a l e n t t o an a b s o l u t e " z e r o r i s k . " The "low r i s k " o r " v a r i o u s l y a c c e p t a b l e " r e g i o n u n d e r t h i s l a b e l i n g scheme w o u l d t h e n , by d i f f e r e n c e b e t w e e n h i g h and i n s i g n i f i c a n t , i d e n t i f y t h o s e s i t u a t i o n s where b a l a n c i n g d e c i s i o n s w h i c h c o n s i d e r r i s k s , b e n e f i t s and j u s t i f i c a t i o n must be made f o r p r i o r i t i z i n g the a p p l i c a t i o n of c r i t i c a l r e s o u r c e s . The e x e r c i s e o f b a l a n c i n g r i s k s and b e n e f i t s i n t h e "low r i s k " r e g i o n i s c l e a r l y an a r e a w h e r e r e g u l a t o r y g u i d a n c e s h o u l d emphas i z e the importance of r e l a t i n g r i s k r e d u c t i o n t o c o s t s , b e n e f i t s and a l t e r n a t i v e r i s k s . T h i s "low r i s k " o r " v a r i o u s l y a c c e p t a b l e " r e g i o n i s t h e a r e a w h e r e c o s t s t o r e d u c e r i s k s h o u l d be j u s t i f i e d and a l t e r n a t i v e s c o n s i d e r e d . F o r j u s t as z e r o r i s k i s n o t g e n e r a l l y a t t a i n a b l e , v e r y l i t t l e r e a l p r o g r e s s toward our g o a l w o u l d be r e a c h e d i f we a t t e m p t e d t o s h i f t a l l " v a r i o u s l y a c c e p t a b l e " r i s k s downward. Regardless of the absence of a governmental p o l i c y e s t a b l i s h ing a b s o l u t e r i s k l i m i t s or boundaries of a c c e p t a b i l i t y , r i s k r e s p o n s e d e c i s i o n s must be made i n many i n d u s t r i a l s i t u a t i o n s . We have f o u n d t h a t c o u p l i n g d i s c i p l i n e d r i s k a s s e s s m e n t p r o c e d u r e s

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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w i t h the r i s k region c l a s s i f i c a t i o n techniques y i e l d s appropriate r e s p o n s e a c t i o n s , and t h e p r o c e s s h a s p r o v e n t o be a p r a c t i c a l t o o l t o deal w i t h these i n h e r e n t l y imprecise situations. U s i n g t h e r i s k a s s e s s m e n t and c l a s s i f i c a t i o n a p p r o a c h i n e v a l u a t i n g waste d i s p o s a l s i t e s i t u a t i o n s should l i k e w i s e a l l o w m a k i n g p r a c t i c a l d e c i s i o n s by c o u p l i n g r i s k l e v e l s w i t h a p p r o p r i ate remedial responses. The s t e p w i s e d e c i s i o n p r o c e s s s h o u l d a l s o be u s e f u l i n e v a l u a t i n g t h e s c o p e o f r i s k s p o s e d by abandoned disposal sites. I f t h e r i s k assessment process leads t o t h e conc l u s i o n that a d i s p o s a l s i t e i s , indeed, posing a s i g n i f i c a n t t h r e a t t o h e a l t h o r t h e e n v i r o n m e n t , a p p r o p r i a t e l e v e l s and t y p e s o f r e s p o n s e s c a n be d e f i n e d . By c o n s i d e r i n g a l l t h e q u a n t i f i a b l e f a c t o r s , t h e i d e n t i f i e d u n c e r t a i n t i e s , and t h e g e o h y d r o l o g i c pred i c t i o n s and p r o j e c t i o n s s p e c i f i c t o e a c h s i t e , s u p p o r t a b l e p r a c t i c a l response d e c i s i o n b made If "high r i s k " c l a s s i f i c a t i o n i s supportable p a r t i c u l a r r i s k i s progresse I f an " i n s i g n i f i c a n t r i s k " c l a s s i f i c a t i o n i s g i v e n , no a c t i o n i s r e q u i r e d s o l e l y t o reduce r i s k t o h e a l t h o r t h e environment. A circumstance worth mentioning a t t h i s point i s the response a p p r o p r i a t e t o d e a l w i t h n u i s a n c e and e s t h e t i c i s s u e s s u c h a s o d o r o r n o i s e when no h a z a r d c a n b e i d e n t i f i e d . A risk classification of " i n s i g n i f i c a n t , " w i t h respect t o h e a l t h o r the environment, w o u l d l i k e l y be s e l e c t e d and no r e s p o n s e j u s t i f i e d i n t h e c a s e o f a d i s p o s a l s i t e e v a l u a t i o n where o n l y o d o r i s t h e p r o b l e m . I n these i n s t a n c e s , a p p r o p r i a t e responses should be developed u s i n g a p r o c e s s w h i c h r e f l e c t s t h e e c o n o m i c , s o c i a l and p o l i t i c a l impacts o f t h e problem r a t h e r than t h e assessment process being d e s c r i b e d w h i c h has been developed t o d e a l w i t h h a z a r d s t o h e a l t h . I n d i s p o s a l s i t e s w i t h i d e n t i f i e d h a z a r d s , t h e more d i f f i c u l t and i n v o l v e d d e c i s i o n s w i l l h a v e t o be f a c e d when t h e c i r c u m stances r e s u l t i n s e l e c t i n g t h e "low r i s k " c l a s s i f i c a t i o n . Since t o t a l c o s t / b e n e f i t c o n s i d e r a t i o n s a p p r o p r i a t e l y come i n t o p l a y — f o r h e r e we hope t o a c h i e v e t h e g r e a t e s t r e d u c t i o n i n r i s k s f o r each d o l l a r spent — t h e response a c t i o n s can vary a c c o r d i n g l y . While r i s k reduction i s the o v e r a l l o b j e c t i v e , reducing the s e l e c ted r i s k l e v e l into the " i n s i g n i f i c a n t " c l a s s i f i c a t i o n i s not a u t o m a t i c a l l y t h e optimum s o l u t i o n s i n c e i t may r e q u i r e i n o r d i n a t e and e x c e s s i v e r e s o u r c e u t i l i z a t i o n . California

Site

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The e v a l u a t i o n o f an a c t u a l d i s p o s a l s i t e i n s o u t h e r n C a l i f o r n i a has been f o l l o w i n g a p a t t e r n o f e v e n t s t h a t , i n ways, f i t s t h e p r o c e s s I have b e e n d i s c u s s i n g . I would l i k e t o share w i t h you t h e h i g h l i g h t s o f t h i s e v a l u a t i o n . S h e l l i s one o f a number o f p a r t i c i p a n t s i n a n e f f o r t t o d e f i n e and r e s o l v e t h e p r o b l e m s p o s e d by a d i s p o s a l s i t e i n a n e s t a b l i s h e d community. The s i t e was p e r m i t t e d d u r i n g t h e 1 9 4 0 ' s , and u s e d f o r d i s p o s a l o f a c i d i c m a t e r i a l s f r o m p e t r o l e u m r e f i n eries i n the area. I t i s i n a developed r e s i d e n t i a l area.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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As m i g h t be e x p e c t e d , when t h e s i t e was i d e n t i f i e d and some of t h e c i r c u m s t a n c e s s u r r o u n d i n g i t s past use were exposed i n t h e m e d i a , t h e r e a c t i o n o f many was t o e x p e c t a n i m m e d i a t e c l e a n - u p . R e l a t i n g t h i s r e a c t i o n t o t h e s t e p - w i s e p r o c e d u r e I have been d i s c u s s i n g , some jumped ahead t o s t e p f o u r - R i s k R e s p o n s e - and c a l l e d f o r an immediate e x c a v a t i o n w i t h o u t having c o n s i d e r e d s t e p s o n e , two o r t h r e e . C a l l i n g f o r immediate clean-up i s e q u i v a l e n t t o c l a s s i f y i n g t h e s i t u a t i o n a s one p o s i n g a h i g h r i s k . D o i n g s o c a n o n l y b e c o n j e c t u r e when o n l y l i m i t e d a n d q u a l i t a t i v e d a t a i s a t hand. T h i s r e a c t i o n was, o f c o u r s e , p r e m a t u r e and d i s r e g a r d e d c o m p l e t e l y s u c h f u n c t i o n s a s i d e n t i f y i n g and e v a l u a t ing the r i s k associated with excavation. A b e t t e r a p p r o a c h t o r e s o l v e community c o n c e r n i s t o move f o r w a r d and f o l l o w t h e s y s t e m a t i c p r o c e d u r e t o f i r s t i d e n t i f y t h e h a z a r d , e v a l u a t e i t s s c o p e , a s s e s s t h e r i s k s p o s e d , and t h e n d e v e l o p an a p p r o p r i a t e At t h e C a l i f o r n i a f e d e r a l , s t a t e , and l o c a l a g e n c i e s was made t o i d e n t i f y t h e n a t u r e o f t h e m a t e r i a l s i n t h e s i t e and t h e p o t e n t i a l f o r a n a d v e r s e effect. Then, w i t h i n d u s t r y p a r t i c i p a t i o n , a p l a n was f o l l o w e d t o d e v e l o p and t h e n i m p l e m e n t a d e t a i l e d and c o m p r e h e n s i v e s i t e evaluation. The d a t a f r o m t h e e v a l u a t i o n e f f o r t w i l l a l l o w m a k i n g a s u p p o r t a b l e d e c i s i o n on t h e h a z a r d s p o s e d by t h e s i t e . A l s o from t h e d a t a g a t h e r e d d u r i n g t h e s t u d y , p r e d i c t i o n s and p r o j e c t i o n s c a n be made a s t o t h e s c o p e o f b o t h t h e c u r r e n t and f u t u r e r i s k s p o s e d by the s i t e . I n a d d i t i o n , t h i s process w i l l provide i n f o r m a t i o n necessary to understand the r i s k s associated w i t h the s p e c i f i c r e m e d i a l measures a v a i l a b l e and under c o n s i d e r a t i o n . From c o n s u l t a t i o n s w i t h t h e a g e n c i e s i n v o l v e d , t h e community, and w i t h t h e i n d u s t r i a l p a r t i c i p a n t s , t h e r i s k s p o s e d b y t h e s i t e s h o u l d be c l a s s i f i a b l e and a p p r o p r i a t e r e s p o n s e and r e m e d i a l meas u r e s a g r e e d upon. We h a v e c o n f i d e n c e t h a t t h i s s c e n a r i o w i l l be f o l l o w e d t o reach a s a t i s f a c t o r y r e s o l u t i o n o f t h e problems associated with this site. Summary I t r u s t t h a t you w i l l agree t h a t t h e use o f a step-wise proc e s s f o r r i s k a s s e s s m e n t and r e s p o n s e d e v e l o p m e n t and t h e companion concept of using r i s k regions o r r i s k c l a s s i f i c a t i o n , o f f e r s a framework f o r p r a c t i c a l d e c i s i o n making. Making t h e e f f o r t a t t h i s time t o d e f i n e b o u n d a r i e s between h i g h , l o w and i n s i g n i f i c a n t r i s k s i n r i s k a s s e s s m e n t s i t u a t i o n s , i s n o t p r e e m p t i n g any u l t i m a t e s o c i e t a l j u d g e m e n t . Eventually governmental p o l i c y w i l l l i k e l y d e f i n e t h e r i s k boundary l i m i t s . I n t h e i n t e r i m , u s i n g s y s t e m s and a p p r o a c h e s t h a t a r e d i r e c t i o n a l l y o r i e n t e d t o reduce r i s k can serve as a base f o r e s t a b l i s h i n g the l o g i c a l framework t h a t f a c i l i t a t e s p r a c t i c a l d e c i s i o n making.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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DREITH

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I t would appear t o be w o r t h w h i l e t o s u p p o r t e f f o r t s t o d e v e l o p r i s k a s s e s s m e n t a p p r o a c h e s a l o n g t h e l i n e s I have d i s c u s s e d r a t h e r t h a n j o i n a c o n s e n s u s s a y i n g t h a t i t c a n n o t b e done, or i n s u p p o r t i n g s e l e c t i n g m a t h e m a t i c a l models w h i c h a r b i t r a r i l y d e f i n e h a z a r d s and r i s k s . We s o l i c i t y o u r c o n s i d e r a t i o n i n d e v e l o p i n g a b r o a d e r c o n sensus which s u p p o r t s t h e premise t h a t a d e l i b e r a t e , d i s c i p l i n e d , s t e p w i s e approach t o making r i s k assessments i s a v a i l a b l e f o r practical application i n disposal s i t e evaluations. Literature 1.

2.

Cited

P. F . D e i s l e r , " D e a l i n g w i t h I n d u s t r i a l Health R i s k s : A Stepw i s e , G o a l - o r i e n t e d Concept," Chapter 15, AAAS S p e c i a l Symposium #65, " R i s k in th T e c h n o l o g i c a l S o c i e t y , " Ed b C Hohenemser and J. Kaspreson P. F . D e i s l e r , "A G o a l - o r i e n t e d Approac to Reducing Industrially-Related Carcinogenic Risks," Drug Metabolism Reviews Vol. 13, No. 5, Sept. 1982 - In P r e s s .

RECEIVED

June 16, 1982.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

6 Methodology for Assessing Uncontrolled Site Problems at the County Level RICHARD A . YOUNG State University College, Department of Geological Sciences, Geneseo, N Y 14454 A N N B. NELSON and LOUISE A . HARTSHORN

1

Monroe County Environmental Management Council, Rochester, N Y 14614

A comprehensive method to inventory inactive waste disposal sites should integrate all available historic, engineering, geologic, water s u p p l y , public agency private pany records in order to develop a complete and accurate site profile. Detailed information on site contents may not be available but areas of potential impact can be evaluated. Where people or drinking water supplies are affected, further investigation is indicated. Historic aerial photographs provide the a c c u racy and documentation r e q u i r e d to compile a p r e c i s e record of site boundaries, p o i n t s of access, and adjacent land use. Engineering b o r ings f o r c o n s t r u c t i o n p r o j e c t s in the vicinity of suspected s i t e s are i n t e g r a t e d w i t h g e o l o g i c information to c o n s t r u c t reasonable hydrogeologic models to evaluate p o t e n t i a l leachate impact on water w e l l s or nearby i n h a b i t a n t s . S i t e s are s y s t e m a t i c a l l y ranked u s i n g matrices w i t h a p p r o p r i a t e v a r i a b l e s , such as geology, land use, or d i s t a n c e to water w e l l s . This k i n d of an e v a l u a t i o n is a necessary step i n the prioritization of sites where little is known about contents and where numbers of sites preclude a comprehensive drilling and testing program. The Monroe County experience i n d i c a t e s that a w e l l - d e s i g n e d study provides a c o n s e r v a t i v e estimate of the number of l a r g e dump sites that r e q u i r e f u r t h e r c o n s i d e r a t i o n . This study p r o v i d e d a comprehensive, fifty-year i n v e n t o r y of all potentially significant sites in a l a r g e urban area (Rochester, New Y o r k ) . 1

Current address: 65 Broad Street, Room 203, Rochester, NY 14614 0097-6156/82/0204-0055$06.00/0 © 1982 American Chemical Society

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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The m e t h o d o l o g y d e s c r i b e d i n t h i s p a p e r t o l o c a t e and c l a s s i f y abandoned dump s i t e s was d e v e l o p e d i n Monroe C o u n t y , New Y o r k i n r e s p o n s e t o a 1978 c o u n t y l e g i s l a t u r e r e q u e s t t o l o c a t e p o t e n t i a l "Love C a n a l " t y p e p r o b l e m s and a 1979 New Y o r k S t a t e l a w r e q u i r i n g c o u n t i e s t o i d e n t i f y abandoned s i t e s . The s y s t e m i s d e s i g n e d t o e v a l u a t e and p r i o r i t i z e a l a r g e number o f s i t e s f o r more d e t a i l e d i n v e s t i g a t i o n . While not a l l p o i n t s w i l l be a p p l i c a b l e i n e v e r y p a r t o f t h e c o u n t r y , t h e g e n e r a l a p p r o a c h w i l l a l l o w government a g e n c i e s t o f o c u s l i m i t e d r e s o u r c e s on t h o s e s i t e s t h a t p o s e t h e g r e a t e s t p o t e n t i a l i m p a c t on human h e a l t h . T h i s paper i s a b r i e f d e s c r i p t i o n of a methodology t h a t w i l l be f u l l y d e s c r i b e d i n a f i n a l r e p o r t t o EPA t o be c o m p l e t e d i n 1982. R a t i o n a l e And

Approac

The h i g h e s t p r i o r i t y f o r t h e Monroe C o u n t y s t u d y was t o l o c a t e s i t e s where p o t e n t i a l l y h a z a r d o u s s u b s t a n c e s i n h i g h c o n c e n t r a t i o n s m i g h t be p r e s e n t i n a r e a s o c c u p i e d by l a r g e numbers of people. T h e r e a r e many o t h e r s i t u a t i o n s where h a z a r d o u s m a t e r i a l s m i g h t h a v e a p o t e n t i a l l o n g - t e r m e f f e c t on humans o r t h e e n v i r o n m e n t t h a t were e x c l u d e d f r o m t h e h i g h e s t p r i o r i t y category i n the design of the study, i . e . , the slow, long-term r e l e a s e o f t o x i c s u b s t a n c e s i n t o s t r e a m s and l a k e s t h r o u g h g r o u n d w a t e r m i g h t be o f g r e a t c o n c e r n i n o t h e r c i r c u m s t a n c e s . However, t h e i m m e d i a t e e f f e c t o f t h e s e l o w c o n c e n t r a t i o n s on a r e a s where l a r g e numbers o f p e o p l e l i v e o r w o r k m i g h t be negligible. F u r t h e r m o r e , d e t e c t i o n of low c o n c e n t r a t i o n s of hazardous substances i n water b o d i e s used f o r d r i n k i n g water or r e c r e a t i o n i s an a r e a o f c u r r e n t c o n c e r n f o r h e a l t h o r w a t e r q u a l i t y a g e n c i e s and s h o u l d be h a n d l e d u n d e r e x i s t i n g p r o g r a m s . I n f o r m a t i o n b e a r i n g on s u c h l o n g - t e r m p r o b l e m s i s n o t i g n o r e d i n t h e p r e s e n t s t u d y b u t w o u l d be r e f e r r e d t o t h e a p p r o p r i a t e a g e n c y when e n c o u n t e r e d . On t h e o t h e r h a n d , p u b l i c o r p r i v a t e w e l l w a t e r s u p p l i e s i n c l o s e p r o x i m i t y t o e x i s t i n g o r abandoned l a n d f i l l s a r e p l a c e d i n the h i g h e s t p r i o r i t y category because the p o t e n t i a l f o r a more d i r e c t c o n t a m i n a t i o n pathway i s o b v i o u s . An i n t e g r a t e d s t u d y s u c h as t h e one u n d e r t a k e n i n Monroe C o u n t y documents a g r e a t d e a l o f h i s t o r i c i n f o r m a t i o n t h a t c o u l d e v e n t u a l l y be u s e d f o r many p u r p o s e s . I t p r o v i d e s comp r e h e n s i v e b a s e l i n e d a t a t h a t m i g h t be u n r e c o v e r a b l e i n f u t u r e y e a r s . P l a n n i n g a c t i v i t i e s and z o n i n g r e q u i r e m e n t s a r e o b v i o u s areas of impact. The i n f o r m a t i o n , once c o l l e c t e d , c o u l d be u s e d by any a g e n c y whose e f f o r t s o r p r i o r i t i e s m i g h t o v e r l a p b u t d i f f e r from the s p e c i f i c g o a l s of the p r e s e n t s t u d y . The k e y t o t h e s u c c e s s f u l i m p l e m e n t a t i o n o f t h i s t y p e o f p r o g r a m i s t h e c a r e f u l o r g a n i z a t i o n and i n t e g r a t i o n by q u a l i f i e d i n d i v i d u a l s o f a l l t h e c r i t i c a l r e s o u r c e s t h a t m i g h t be 4

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overlooked o r i n e f f e c t i v e l y u t i l i z e d i n a l e s s comprehensive e f f o r t w i t h more l i m i t e d t i m e c o n s t r a i n t s . I n v o l v e m e n t o f p e r s o n n e l from a l l a f f e c t e d o r p e r i p h e r a l agencies i s s t r o n g l y recommended. H i s t o r i c a e r i a l p h o t o g r a p h i c a n a l y s i s i s t h e b e s t way t o confirm a c t u a l o r p o t e n t i a l s i t e boundaries. This, i n turn, a l l o w s p e r s o n n e l and r e s o u r c e s t o b e f o c u s e d o n t h o s e a r e a s where p h y s i c a l d o c u m e n t a t i o n o f s i t e s i s r e a s o n a b l y a c c u r a t e . The g e o l o g i c a n a l y s i s a i d s i n b o t h t h e s e a r c h f o r a n d p r i o r i t i z a t i o n o f p o t e n t i a l s i t e s , b u t t h e d a t a must b e i n t e grated w i t h the i n f o r m a t i o n developed by r e c o r d searches, i n t e r v i e w s and the c a r e f u l development o f a comprehensive s i t e activity profile. F i n a l l y , t h i s e f f o r t i s n o t meant t o r e p l a c e t h o s e t e c h n i c a l s t u d i e s which have d e a l known h a z a r d o u s w a s t e s i t e m a t i o n i s a v a i l a b l e o n s i t e h i s t o r y , c o n t e n t s , and h y d r o g e o l o g y . The p r e s e n t s t u d y s h o u l d r e d u c e t h e need f o r e x p e n s i v e d r i l l i n g and t e s t i n g p r o g r a m s and p r o v i d e a means f o r t h e i r r a t i o n a l , implementation. Site

Identification

I n c o n d u c t i n g a g e n e r a l s u r v e y o f abandoned dump s i t e s , t h e r e a r e many s o u r c e s o f i n f o r m a t i o n w h i c h must b e u s e d i n combination t o i d e n t i f y and/or v e r i f y s i t e l o c a t i o n s and t o characterize site activity. The Monroe C o u n t y m e t h o d o l o g y u s e s h i s t o r i c a e r i a l photographs i n s t e r e o s c o p i c p a i r s as the primary r e s o u r c e t o d e v e l o p a n i n f o r m a t i o n b a s e , b u t no s i n g l e s o u r c e s h o u l d b e depended upon e n t i r e l y . A e r i a l photographs are the most r e l i a b l e r e s o u r c e f o r i d e n t i f y i n g s i t e b o u n d a r i e s , p e r i o d s o f o p e r a t i o n , s i t e d r a i n a g e , and p r e - e x i s t i n g u s e s o r f e a t u r e s s u c h a s sand and g r a v e l o p e r a t i o n s , b o r r o w p i t s , s u r f a c e p o n d i n g , and a c c e s s r o u t e s . However, i t i s n o t a l w a y s p o s s i b l e t o d i s t i n q u i s h dumping f r o m " c l e a n " f i l l o r c o n s t r u c t i o n a c t i v i t y o n p h o t o g r a p h s . The i n f o r m a t i o n must b e s u p p l e m e n t e d b y o t h e r sources. R e p o r t s , maps, r e c o r d s , i n t e r v i e w s a n d i n f o r m a t i o n from the g e n e r a l p u b l i c a l l p r o v i d e i n f o r m a t i o n t h a t i s u s e f u l in constructing a site activity profile. These s o u r c e s , used w i t h o u t a i r p h o t o i n f o r m a t i o n , may b e i n s u f f i c i e n t t o l o c a t e s i t e s a d e q u a t e l y and g e n e r a l l y do n o t p r o v i d e a c c u r a t e i n f o r m a t i o n on s i t e boundaries. I t i s the combination o f a l l a v a i l a b l e r e s o u r c e s t h a t i s the key t o a c c u r a t e s i t e c h a r a c t e r i z a t i o n . D a t a S o u r c e s . The u s e f u l s o u r c e s o f d a t a i n c l u d e : . A e r i a l photographs i n s t e r e o s c o p i c p a i r s f o r s e l e c t e d years . Records from l o c a l and s t a t e h e a l t h department and c o n s e r v a t i o n agencies . Environmental a t l a s e s . Government p u b l i c a t i o n s on h a z a r d o u s w a s t e s i t e s

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. C o u n t y s o i l s maps . H i s t o r i c r e s o u r c e s (newspaper c l i p p i n g s , a r t i c l e s , c i t y d i r e c t o r i e s , f i r e i n s u r a n c e maps, p l a t b o o k s , i n d u s t r i a l surveys) . I n t e r v i e w s w i t h p u b l i c o f f i c i a l s , agency employees . P u b l i c c a l l - i n campaign. G e n e r a l S u r v e y . The g e n e r a l s u r v e y i s c o n d u c t e d f o r one USGS q u a d r a n g l e s h e e t a t a t i m e . H i s t o r i c a e r i a l p h o t o g r a p h s are i n t e r p r e t e d f o r s e l e c t e d years ( g e n e r a l l y ten year i n t e r v a l s ) t o i d e n t i f y abandoned dumps. A r e c o r d o f i n t e r p r e t a t i o n s i s made on m y l a r s h e e t s a t t a c h e d t o one p h o t o i n e a c h s t e r e o p a i r . These o v e r l a y s h e e t s a r e r e t a i n e d as i m p o r t a n t permanent d o c u m e n t a t i o n f o r the study. S i n c e i t i s not always p o s s i b l e to d i s t i n g u i s h between cons t r u c t i o n , f i l l i n g , an i n i t i a l l y g i v e n one o f S i t e s i n t h e " P o s s i b l e Dump" and " U n s p e c i f i e d F i l l " categories w i l l n e e d s u p p l e m e n t a l i n f o r m a t i o n t o d e t e r m i n e w h e t h e r dumping a c t u a l l y occurred. The m i x t u r e o f t y p e s t h a t o c c u r r e d f o r one q u a d r a n g l e i n Monroe C o u n t y i s shown i n F i g u r e 1. A f t e r the photos are i n t e r p r e t e d f o r each s e l e c t e d y e a r , t h e i n f o r m a t i o n f r o m a l l y e a r s must be combined f o r e a c h s i t e . A w r i t t e n r e c o r d o f s i t e a c t i v i t y i s c o m p i l e d and r e c o r d e d . A maximum s i t e b o u n d a r y map i s p r e p a r e d u s i n g l a r g e s c a l e ( l " = 2 0 0 ) maps. O r t h o p h o t o maps a r e b e s t f o r t h i s p u r p o s e i f a v a i l a b l e . L a s t l y , a g e n e r a l s u r v e y map a t t h e s c a l e o f 1:24000 i s c o m p l e t e d f o r e a c h q u a d r a n g l e by t r a n s f e r r i n g b o u n d a r i e s f r o m t h e l a r g e r s c a l e maps ( F i g u r e 1 ) . S i t e s a r e c l a s s i f i e d f o r c u r r e n t l a n d use f r o m t h e most r e c e n t s e t o f a e r i a l p h o t o g r a p h y . One o f s i x l a n d use categories is applied. T h e s e w i l l e v e n t u a l l y n e e d t o be v e r i f i e d by f i e l d inspection. . 2 4 - h o u r o c c u p a n c y on o r w i t h i n 100 f e e t o f t h e s i t e ( r e s i d e n t i a l u s e , h o s p i t a l s , n u r s i n g homes) . P a r t - t i m e o c c u p a n c y on o r w i t h i n 100 f e e t o f t h e s i t e (commerc i a l establishments, industry) . 2 4 - h o u r o c c u p a n c y w i t h i n 1,000 f e e t of s i t e . P a r t - t i m e o c c u p a n c y w i t h i n 1,000 f e e t of s i t e . 2 4 - h o u r o c c u p a n c y w i t h i n 1,000-2,500 f e e t o f s i t e . P a r t - t i m e o c c u p a n c y w i t h i n 1,000-2,500 f e e t o f s i t e f

Geologic

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A g e n e r a l g e o l o g i c a n a l y s i s of the e n t i r e r e g i o n under study i s e s s e n t i a l to the development of a r a t i o n a l approach to s i t e prioritization. Such a b r o a d - b a s e d a n a l y s i s a l s o s e r v e s as t h e frame of r e f e r e n c e f o r s i t e s p e c i f i c s t u d i e s d u r i n g the l a t e r phases of the p r o j e c t . The i m p o r t a n t components o f a g e n e r a l g e o l o g i c a n a l y s i s a r e

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Categories

D-Identifiable: S i t e s where i n f o r m a t i o n o n dumping a c t i v i t y i s known f r o m p u b l i c r e c o r d s , i n t e r v i e w s w i t h government o r i n d u s t r y o f f i c i a l s , t h e p u b l i c c a l l - i n c a m p a i g n , i n d u s t r i a l s u r v e y s , o r where dumping a c t i v i t y i s c l e a r l y e v i d e n t on a e r i a l photographs. P-Possible: S i t e s where f i l l i n g a c t i v i t y i s e v i d e n t b u t t h e r e has b e e n no c o n f i r m a t i o n a s t o w h e t h e r o r n o t dumping has o c c u r r e d . However, based on the l o c a t i o i t w o u l d a p p e a r t h a t dumpin adjacent t o i n d u s t r i a l o commercia a c t i v i t i e s , maintenance a r e a s , l a r g e c o n s t r u c t i o n s i t e s and p u b l i c f a c i l i t i e s such a s sewage t r e a t m e n t p l a n t s a n d i n c i n e r a t o r s s h o u l d b e e v a l u a t e d a s p o s s i b l e dumps. U-Unspecified: S i t e s that are apparent e i t h e r as recent surface d i s t u r bances o r t o p o g r a p h i c changes t h a t were not p r e s e n t on e a r l i e r photographs. S i t e s that are obviously clean f i l l f o r construct i o n purposes are not i n c l u d e d i n t h i s category nor are they annotated. (Such s i t e s may b e i d e n t i f i e d b y t h e r e l a t i v e l y r a p i d completion o f a c t i v i t y f o l l o w e d by the appearance o f a h i g h w a y , new b u i l d i n g o r s t r u c t u r e o n more r e c e n t p h o t o g r a p h s . ) L-Lagoons: P o t e n t i a l l i q u i d waste d i s p o s a l areas that are e i t h e r s u g g e s t e d b y a s s o c i a t e d a c t i v i t y o n t h e p h o t o g r a p h s o r a r e known to have e x i s t e d . Standing w a t e r i n borrow p i t s o r q u a r r i e s i s not g e n e r a l l y placed i n t h i s category unless a s s o c i a t e d w i t h dumping. J-Auto J u n k y a r d s and S a l v a g e A r e a s : Such s i t e s may c o n t a i n s i g n i f i c a n t s u r f a c e d i s p o s a l o r s p i l l s o r o i l , t r a n s m i s s i o n and h y d r a u l i c f l u i d s , o r s o l v e n t s . S-Suspicious: A r e a s w h e r e u n u s u a l o r u n i d e n t i f i a b l e a c t i v i t y has o c c u r r e d that i s not r e a d i l y r e c o g n i z a b l e . S i t e s are placed i n t h i s c a t e g o r y p e n d i n g more c o m p l e t e a n a l y s i s t h a t w i l l r e s u l t i n one o f t h e above d e s i g n a t i o n s o r e l i m i n a t i o n .

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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Figure 1. General survey map of sites in the Rochester West quadrangle. Key: dump; H> possible dump; • , unspecified fill. (Reproduced, with permission, from Ref.l.)

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those f a c t o r s which d i r e c t l y i n f l u e n c e the p r o d u c t i o n , c o n t a i n ment, a t t e n u a t i o n o r m i g r a t i o n o f l e a c h a t e . These g e n e r a l l y i n v o l v e the groundwater system, the s o i l o r r o c k p e r m e a b i l i t y , and t h e s t r u c t u r e s w i t h i n t h e o v e r b u r d e n o r r o c k t h a t c o n t r o l e i t h e r t h e d i r e c t i o n o f movement, r a t e o f movement, o r l o c a l concentration of f l u i d s . I n most c a s e s , l a n d f i l l s o r o l d dumps are l o c a t e d i n unconsolidated s o i l s o r overburden but occasiona l l y the c h a r a c t e r o f the l o c a l bedrock i s a l s o s i g n i f i c a n t . Any g e o l o g i s t w o r k i n g o n a p r o j e c t s u c h a s t h i s n e e d s t o e v a l u a t e the c r i t i c a l f a c t o r s w i t h i n the p a r t i c u l a r r e g i o n under study. When d e a l i n g w i t h abandoned l a n d f i l l s t h a t w e r e s t a r t e d o r c o m p l e t e d p r i o r t o t h e l a t e 1 9 7 0 s , i t s h o u l d b e assumed t h a t w a s t e s w e r e g e n e r a l l y p l a c e d i n n a t u r a l o r man-made d e p r e s s i o n s without u t i l i z a t i o n of s o p h i s t i c a t e d p r e p a r a t i o n o r containment techniques. Thus, the p r o p e r t i e s and s t r u c t u r e s o f the n a t u r a l o v e r b u r d e n and r o c k f o r m a t i o n natural migration of leachat site. W h i l e t h e Monroe C o u n t y s t u d y e m p h a s i z e s t h e p r o b l e m s encountered i n the g l a c i a l overburden d e p o s i t s b o r d e r i n g Lake O n t a r i o , the b a s i c approach should be a p p l i c a b l e , w i t h minor m o d i f i c a t i o n s , t o any r e g i o n a l a n a l y s i s o f h y d r o g e o l o g i c c o n d i tions. The f i r s t p h a s e o f t h e g e n e r a l g e o l o g i c a n a l y s i s c o n s i s t s o f t h e c o l l e c t i o n o f a l l r e a d i l y a v a i l a b l e p u b l i s h e d o r unpubl i s h e d d a t a f o r t h e c o n s t r u c t i o n o f r e g i o n a l g e o l o g i c maps s u c h as t h o s e shown i n F i g u r e s 2, 3, a n d 4. The c o l l e c t i o n o f a d d i t i o n a l unpublished data should continue throughout the p e r i o d o f s t u d y b e c a u s e u s e f u l o r u n i q u e i n f o r m a t i o n can c o n t i n u e t o b e located. The t y p e s o f s o u r c e s commonly u s e d i n t h e d e v e l o p m e n t of a g e o l o g i c d a t a base f o r b o t h g e n e r a l o r s i t e - s p e c i f i c g e o l o g i c models a r e : . G e o l o g i c maps and r e p o r t s : p u b l i s h e d l i t e r a t u r e and s t u d e n t t h e s e s / d i s s e r t a t i o n s ; o p e n - f i l e r e p o r t s o f agencies such as U n i t e d S t a t e s G e o l o g i c a l S u r v e y ; government d o c u m e n t s . . C o u n t y s o i l s maps: o l d and new v e r s i o n s o f U n i t e d S t a t e s D e p a r t m e n t o f A g r i c u l t u r e maps d e s c r i b i n g s o i l t y p e s a n d l o c a t i o n s o f dumps o r "made l a n d " (good f o r s h a l l o w d e p t h o f overburden o n l y ) . . A e r i a l p h o t o g r a p h s a n d t o p o g r a p h i c maps: u s e d f o r geomorphol o g i c a l a n a l y s i s o f l a n d f o r m s i f need t o supplement o r c o n f i r m published data. Compare o l d and r e c e n t p r i n t s o r maps, i f available. . E n g i n e e r i n g data from p u b l i c o r p r i v a t e agencies o r f i r m s (especially exploratory boring logs) Highway/bridge plans o r surveys. Town, v i l l a g e o r c o u n t y c o n s t r u c t i o n / m a i n t e n a n c e projects. U t i l i t i e s , r a i l r o a d s , p i p e l i n e companies, c a n a l s . D r i l l i n g and s o i l t e s t i n g f r o m e n g i n e e r i n g f i r m s . Architectural firms. O i l , gas and w a t e r w e l l d r i l l e r s . T

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

Figure 2. Subsurface bedrock contour map with selected surface geology for Rochester East and Rochester West 7.5-min topographic quadrangles. Contour interval is 25 ft. Map width is 12.6 mi.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

Figure 3. Generalized groundwater contour map for Rochester East and Rochester West topographic quadrangles. The 25-ft contour intervals show water elevations in overburden and may reflect some seasonal variations. Map width is 12.6 mi.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

Figure 4. Overburden thickness map for Rochester East and Rochester West topographic quadrangles from same data points as Figure 2. R designates rock outcrops. Map width is 12.6 mi.

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Sewer and w a t e r d i s t r i c t a g e n c i e s . M i n i n g , q u a r r y i n g and t u n n e l i n g v e n t u r e s . P u b l i c b u i l d i n g s , a i r f i e l d s and l a r g e i n d u s t r i a l

firms.

G e o l o g i c O v e r l a y Maps. U s i n g a l l a v a i l a b l e s o u r c e s , maps s u c h a s t h o s e i n F i g u r e s 2, 3, a n d 4 a r e c o n s t r u c t e d . I t i s recommended t h a t a common s c a l e b e a d o p t e d f o r a l l s u c h g e n e r a l s u r v e y map p r o d u c t s a n d t h a t t h e y b e c o m p i l e d o n t r a n s p a r e n t o v e r l a y s so t h a t a l l t y p e s o f i n f o r m a t i o n can be e a s i l y t r a n s p o s e d o n t o o r compared w i t h t h e g e n e r a l s u r v e y s i t e maps. T o p o g r a p h i c maps w i t h a s c a l e o f 1:24,000 a r e v e r y c o n v e n i e n t f o r t h i s p u r p o s e a s much g e o l o g i c d a t a a r e r o u t i n e l y p u b l i s h e d on t h i s s c a l e b y s t a t e and f e d e r a l a g e n c i e s . T h e s e maps a n d t h e d a t a f r o m w h i c h t h e y a r e g e n e r a t e d h a v e the f o l l o w i n g uses: . Development and improve water model t h a t i n c l u d e depth directions. . D e v e l o p m e n t o f a r e g i o n a l p e r s p e c t i v e c o n c e r n i n g a r e a s where l a n d f i l l o r l e a c h a t e problems would e i t h e r be reduced o r aggravated by l o c a l g e o l o g i c c o n d i t i o n s . . D e v e l o p m e n t o f a b a s i s upon w h i c h t o p r i o r i t i z e o r o r g a n i z e t h e search f o r s i t e s w i t h p o t e n t i a l f o r s i g n i f i c a n t impact. . A l l o w a n a g e n c y t o f o c u s i t s l i m i t e d r e s o u r c e s i n t h e most c r i t i c a l areas. . E x t r a p o l a t i o n o f s u b s u r f a c e c o n d i t i o n s t o s i t e s where no d a t a c a n b e l o c a t e d f r o m s i m i l a r ones w h e r e d e t a i l e d i n f o r m a t i o n exists. Geologic Ranking Process. Once a l l t h e g e n e r a l maps h a v e been prepared and s u b s u r f a c e e n g i n e e r i n g i n f o r m a t i o n c o m p i l e d , the g e o l o g i c r a n k i n g p r o c e s s can be a p p l i e d u s i n g the G e o l o g i c Ranking Sheet ( F i g u r e 5 ) . T a b l e I I e x p l a i n s the c a t e g o r i e s on the G e o l o g i c Ranking Sheet. T h i s r a n k i n g s h e e t has b e e n d e v i s e d f o r t h e f o l l o w i n g reasons : . To p r o v i d e a means o f o r g a n i z i n g t h e p r o c e s s o f s i t e c o m p a r i s o n . . To m i n i m i z e i n c o n s i s t e n c i e s and o v e r s i g h t s t h a t c o u l d o c c u r when d e a l i n g w i t h l a r g e amounts o f d a t a . . To p r o v i d e a r e c o r d f o r o t h e r p r o j e c t p e r s o n n e l t h a t c a n b e u p d a t e d and w i l l a l l o w d i s c u s s i o n o r r e v i e w o f s i t e c h a r a c teristics. A r a n k i n g scheme s u c h a s t h i s i s b a s i c a l l y a n i n f o r m a t i o n g a t h e r i n g and documentation d e v i c e t h a t would be e s p e c i a l l y u s e f u l , i f p r o j e c t p e r s o n n e l changed. S t r i c t n u m e r i c a l s i t e r a n k i n g s should be c o n s i d e r e d o n l y as approximations o f s i t e c h a r a c t e r i s t i c s and g e o l o g i c e x p e r t i s e s h o u l d b e s u b s t i t u t e d w h e r e a p p r o p r i a t e . The s y s t e m d e s c r i b e d h e r e r e q u i r e s k n o w l e d g e a b l e d e c i s i o n s t o b e made f o r e a c h o f t h e "presumed e f f e c t s " a n d t h e r a n k i n g p r o c e s s s h o u l d b e done b y a n i n d i v i d u a l w i t h hydrogeologic background.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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SITES

G E O L O G I C R A N K I N G SHEET FOR G E N E R A L C O M P A R I S O N OF A B A N D O N E D L A N D F I L L / D U M P SITES

S Y M B O L S USED IN C O L U M N S SITE N A M E / N O . _

X PROBABLE E F F E C T U

U N C E R T A I N : LIKELY EFFECT

®

E F F E C T OF OVERRIDING

SIGNIFICANCE

Superscripts refer to footnotes.

OVERBURDEN GEOLOGY

n

.01 HIGHEST PRIORITY (17-21 PTS) .02 INTERMEDIATE PRIORITY (12-16 PTS)

LOWER HAZARD

HIGHER HAZARD

FACTORS T O BE EVALUATED

INTERMEDIATE (UNCERTAIN)

>

w

PRESUMED EFFECT

SITE R A N K ( C H E C K ONE)

.03 LOWEST PRIORITY (7-11

PTS)

T H E CRITICAL F A C T O R S MUST BE RATED AS U N C E R T A I N (U), T H E RANK S H O U L D BE TENTATIVE.

2

ESTIMATED PERMEABILITY

RELIEF,

ADDITIONAL F A C T O R S (CIRCLE A N D A D D T O CHART)

4

GEOMORPHOLOGY THESE POINTS M A Y INCREASE ( + 1), D E C R E A S E (-1), OR N O T A F F E C T (0) SCORE

S E P A R A T I O N OF WASTE FROM GROUNDWATER '

s

GROUNDWATER GRADIENT

VERY L A R G E SITES (20+ ACRES) ENGINEERING/GEOLOGIC DATA O N OR NEAR SITE α

6

BEDROCK CHARACTER

G E O L O G Y EXTRAPOLATED C O N F I D E N T L Y F R O M NEARBY

7

+1

-ι, +

1

ο, -ι,+1

SOIL M I N E R A L O G Y ; TEXTURES 8

NUMBER OF ENTRIES MULTIPLIER

3

2

1

DESCRIBE IMPORTANT OR OVERRIDING FACTORS BELOW IF APPROPRIATE (DESCRIBE SPECIAL CONDITIONS):

ENTRIES X MULITPLIER SUBTOTAL. ADDITIONAL FACTORS . T O T A L POINTS: SITE R A N K .

Figure 5. Geologic ranking sheet. This form serves as a general guide for evaluating and recording geologic information on specific sites. See Table II for explanation.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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Table I I . Description of Factors

on G e o l o g i c

Ranking

Sheet

1.

PRESUMED EFFECT: A d e c i s i o n i s r e q u i r e d a s t o w h e t h e r e a c h i n f e r r e d o r documented FACTOR w o u l d i n c r e a s e o r d e c r e a s e t h e hazard r e l a t i v e t o leachate production, migration, o r a t t e n u a t i o n . No s i m p l e , u n i f o r m g u i d e l i n e s can b e s e t f o r t h t h a t cover a l l s i t u a t i o n s o r geohydrologic c o m p l e x i t i e s .

2.

OVERBURDEN GEOLOGY: From i n f e r r e d n a t u r e o f u n c o n s o l i d a t e d sediments would l e a c h a t e occurrence be l i k e l y t o i n c r e a s e o r d e c r e a s e human e x p o s u r

3.

ESTIMATED PERMEABILITY: I s e s t i m a t e d p e r m e a b i l i t y o f u n c o n s o l i d a t e d m a t e r i a l s l i k e l y t o i n c r e a s e o r decrease exposure risks? Include estimated e f f e c t of e i t h e r a q u i f e r s o r aquicludes o r i n f e r r e d combinations.

4.

R E L I E F , GEOMORPHOLOGY: Does r e l i e f o n o r a d j a c e n t t o t h e s i t e i n f l u e n c e the occurrence o r m i g r a t i o n o f l e a c h a t e so as to i n c r e a s e o r decrease the exposure hazard?

5.

SEPARATION OF WASTE FROM GROUNDWATER: Does t h e e s t i m a t e d depth t o the w a t e r t a b l e i m p l y a h i g h o r low r i s k f o r contamination o r leachate production. Relate t o permeability and g r a d i e n t f a c t o r s .

6.

GROUNDWATER GRADIENT: G r a d i e n t i s d e p e n d e n t o n l o c a l r e l i e f , e s t i m a t e d p e r m e a b i l i t y , a q u i f e r c h a r a c t e r i s t i c s and r a i n f a l l patterns. Steep o r f l a t g r a d i e n t s by themselves cannot be presumed t o h a v e s i m i l a r e f f e c t s i n e a c h c a s e . Judgment i s r e q u i r e d on l o c a l c o n d i t i o n s .

7.

BEDROCK CHARACTER: I s l o c a l b e d r o c k a n i m p o r t a n t f a c t o r i n l o c a l h y d r o l o g i e system? I f s o , do t e x t u r e s o r s t r u c t u r e s i n b e d r o c k p r o d u c e asymmetry o r enhanced f l o w o f p o t e n t i a l l e a c h a t e plume ( f l o w a l o n g b e d d i n g , j o i n t s , f a u l t s , o r solution channels).

8.

SOIL PROPERTIES, TEXTURE AND BEHAVIOR: A r e t h e r e known t e x t u r a l o r m i n e r a l o g i c a l f a c t o r s t h a t c o u l d enhance o r d i m i n i s h l e a c h a t e m i g r a t i o n , such a s s t r o n g c a t i o n exchange o r s w e l l i n g / s h r i n k i n g c l a y s ( c r a c k i n g ) ? Are seasonal e f f e c t s such as r a i n f a l l duration, i n f i l t r a t i o n capacity, freeze-thaw condit i o n s , vegetation cover, etc. ofs i g n i f i c a n c e ?

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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ASSESSMENT

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HAZARDOUS

WASTE

SITES

The r a n k i n g s h e e t was d e s i g n e d t o d i v i d e p o t e n t i a l s i t e s i n t o h i g h , i n t e r m e d i a t e o r l o w p r i o r i t i e s b a s e d on a n t i c i p a t e d g e o l o g i c c o n d i t i o n s governing l e a c h a t e (groundwater) occurrence, p r o d u c t i o n , m i g r a t i o n o r a c c u m u l a t i o n , b u t i t i s o n l y one comp o n e n t o f an i n t e g r a t e d a s s e s s m e n t s y s t e m . I t s prime c o n s i d e r a t i o n i s the p o t e n t i a l or i n f e r r e d e f f e c t s t h a t l e a c h a t e contamin a t i o n w o u l d h a v e on p e o p l e n e a r t h e s i t e s . H i g h p r i o r i t y s i t e s a r e t h o s e where h a z a r d o u s m a t e r i a l s m i g h t a c c u m u l a t e , move r e a d i l y a t s h a l l o w d e p t h s , o r r e a p p e a r a t t h e s u r f a c e i n c o n c e n t r a t e d amounts. Low p r i o r i t y s i t e s a r e t h o s e a d j a c e n t t o l a k e s , r a v i n e s , o r on s t e e p s l o p e s and presumed t o h a v e b e e n w e l l d r a i n e d f o r an e x t e n d e d p e r i o d . Any l a r g e s i t e w i t h known h a z a r d o u s c o n t e n t s s h o u l d be e v a l u a t e d i n d i v i d u a l l y and r e f e r r e d t o t h e a p p r o p r i a t e a g e n c y r e g a r d l e s s of i t s p o s i t i o n i n the g e o l o g i c r a n k i n g system. Intermediate s i t e d e s c r i b e d a b o v e . They c o n d i t i o n s c o n t a i n and i s o l a t e any l e a c h a t e o r p a r t i a l l y attenuate i t s e f f e c t s . P o t e n t i a l water w e l l contamination i n v o l v e s g e o l o g i c cons i d e r a t i o n s but s i t e s near p u b l i c or p r i v a t e d r i n k i n g water s u p p l i e s a r e t r e a t e d s e p a r a t e l y due t o t h e p o t e n t i a l d i r e c t risks involved. Use o f t h e R a n k i n g S h e e t . E a c h f a c t o r on t h e r a n k i n g s h e e t i s a n a l y z e d as t o w h e t h e r i t i n c r e a s e s o r d e c r e a s e s t h e p o t e n t i a l risk for a site. A v a i l a b l e e n g i n e e r i n g i n f o r m a t i o n and p o t e n t i a l i n t e r r e l a t i o n s among f a c t o r s n e e d t o be c o n s i d e r e d . When t h e s h e e t s u b t o t a l i s computed, t h e " a d d i t i o n a l f a c t o r s " a r e e v a l u a t e d and a t o t a l s c o r e computed. I t i s i m p o r t a n t t h a t b o r d e r l i n e c a s e s be c a r e f u l l y e v a l u a t e d and a t e n t a t i v e r a n k a s s i g n e d i f necessary, pending f u r t h e r data c o l l e c t i o n . S p e c i a l problems s h o u l d be n o t e d i n t h e s p a c e p r o v i d e d a t t h e b o t t o m o f t h e s h e e t . T h i s s y s t e m i s d e s i g n e d t o d e a l w i t h a l a r g e number o f abandoned s i t e s w h e r e i n f o r m a t i o n i s s c a r c e o r d i f f i c u l t t o locate. I t i s n o t meant t o r e p l a c e t h e e l a b o r a t e s y s t e m s f°?2) r a n k i n g known h a z a r d o u s w a s t e s i t e s s u c h as t h o s e by L e G r a n d and K u f s e t a l . The Monroe C o u n t y s t u d y i s i n t e n d e d t o broadly p r i o r i t i z e s i t e s , r a p i d l y i d e n t i f y p o t e n t i a l l y high r i s k s i t e s and a l l o w t h e most e f f i c i e n t use o f f u n d s a v a i l a b l e f o r l a t e r t e s t i n g or subsurface i n v e s t i g a t i o n s . Refinement of S i t e

Information

Upon c o m p l e t i o n o f t h e s i t e i d e n t i f i c a t i o n p h a s e , t h e r e w i l l be s i t e s c a t e g o r i z e d as " P o s s i b l e Dumps" o r " U n s p e c i f i e d F i l l s . " A d d i t i o n a l i n f o r m a t i o n must be o b t a i n e d i n o r d e r t o c l a r i f y w h i c h o f t h e s e s i t e s w e r e a c t u a l l y u s e d as dumps. Information can be o b t a i n e d f r o m e x i s t i n g a g e n c y r e c o r d s , i n t e r v i e w s w i t h

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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l o c a l o f f i c i a l s , waste h a u l e r s , i n d u s t r i a l employees, h i s t o r i c documents a n d s t r e e t and b u s i n e s s d i r e c t o r i e s . T a b l e I I I i n d i c a t e s t h e number o f dumps i d e n t i f i e d f o r one town i n Monroe C o u n t y b e f o r e and a f t e r c o n t a c t w i t h l o c a l o f f i c i a l s a n d f i e l d i n s p e c t i o n s . The f i n d i n g s i l l u s t r a t e t h a t t h e m e t h o d o l o g y does n o t o v e r e s t i m a t e t h e number o f dumps a n d p o s s i b l e dumps i d e n t i f i e d t h r o u g h p h o t o i n t e r p r e t a t i o n . However, t h e p r o c e s s was a b l e t o i d e n t i f y a p p r o x i m a t e l y t w i c e t h e number o f dumps i n i t i a l l y i d e n t i f i e d t h r o u g h a c a l l - i n c a m p a i g n a n d p r e l i m i n a r y i n t e r v i e w s w i t h t h e same l o c a l o f f i c i a l s ( 1 0 ) .

Table I I I .

C a t e g o r i z a t i o n o f S i t e s , G r e e c e , New Y o r k

A f t e r Photo I n t e r p r e t a t i o n

11

19

11

41

with Local O f f i c i a l s

19

13

6

38*

After F i e l d Inspection

21

11

6

38*

After Final

Interviews

*Three s i t e s were e l i m i n a t e d because they were found to be c l e a n f i l l for construction o r landscaping.

Once t h e s i t e c a t e g o r i e s a r e r e f i n e d , r e s e a r c h i s c o n d u c t e d t o d e t e r m i n e t h e l o c a t i o n o f p u b l i c and p r i v a t e d r i n k i n g w a t e r s u p p l i e s i n p r o x i m i t y t o known dump s i t e s . Where p r i v a t e w e l l s a r e f o u n d w i t h i n 1,000 f e e t o f a known dump, o r p u b l i c w a t e r w e l l s w i t h i n one-half m i l e , geologic c o n d i t i o n s are c a r e f u l l y evaluated t o determine i f contamination could occur. When t h i s d e t e r m i n a t i o n i s p o s i t i v e , the s i t e s are r e f e r r e d t o the approp r i a t e l o c a l o r s t a t e agency f o r w a t e r w e l l t e s t i n g . Site

Prioritization

A l l dump s i t e s a r e now p r i o r i t i z e d i n a m a t r i x u s i n g g e o l o g y and l a n d use o n t h e two a x e s . T a b l e I V shows t h e r a n k i n g o f dump s i t e s f o r t h e town o f G r e e c e .

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

final

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T a b l e I V . P r i o r i t i z a t i o n M a t r i x f o r Waste D i s p o s a l S i t e s , Town o f G r e e c e , New Y o r k L a n d Use

Geologic Categoies

Categories

.01

.02

.03

.01

4

0

0

.02

3

5

0

.03

3

5

1

N o t e : The s i t e s c l a s s i f i e p r i o r i t y i n terms of p o t e n t i a Summary and

Conclusions

I n t h e f i n a l a n a l y s i s , no g e n e r a l p r o g r a m f o r i d e n t i f y i n g abandoned dump s i t e s c a n e v e r c o m p l e t e l y d e t e r m i n e t h e l o c a t i o n and c o n t e n t s o f a l l h a z a r d o u s w a s t e d i s p o s a l a r e a s . The Monroe C o u n t y a p p r o a c h i s d e s i g n e d t o p r o v i d e g e n e r a l i n f o r m a t i o n on a l a r g e number o f p r e v i o u s l y undocumented s i t e s , as w e l l as a method f o r l o c a l , s t a t e and f e d e r a l a g e n c i e s t o p r i o r i t i z e s i t e s f o r more d e t a i l e d s i t e i n v e s t i g a t i o n and t e s t i n g . A p p l i c a t i o n o f t h e p r o c e d u r e s w i l l r e d u c e t h e e x p e n s e o f c o s t l y d r i l l i n g and t e s t i n g p r o g r a m s by f o c u s i n g r e s o u r c e s on t h e most c r i t i c a l sites. Acknowledgments M a j o r p o r t i o n s of t h i s a r t i c l e were p r i n t e d i n the P r o c e e d i n g s o f t h e N a t i o n a l C o n f e r e n c e on Management o f U n c o n t r o l l e d H a z a r d o u s Waste S i t e s , O c t o b e r 1981(1) and a r e r e p r i n t e d w i t h p e r m i s s i o n of the Hazardous M a t e r i a l s C o n t r o l Research Institute. T h i s t e x t , h o w e v e r , has b e e n r e v i s e d t o r e f l e c t f u r t h e r r e f i n e m e n t s i n the methodology t h a t have o c c u r r e d s i n c e the o r i g i n a l p u b l i c a t i o n . T h i s s t u d y has b e e n c o n d u c t e d u n d e r t h e d i r e c t i o n o f t h e Monroe C o u n t y L a n d f i l l R e v i e w C o m m i t t e e , c o m p r i s e d o f r e p r e s e n t a t i v e s o f t h e Monroe C o u n t y E n v i r o n m e n t a l Management C o u n c i l , t h e Monroe C o u n t y D e p a r t m e n t s o f H e a l t h and P l a n n i n g , t h e New Y o r k S t a t e D e p a r t m e n t s o f H e a l t h and E n v i r o n m e n t a l C o n s e r v a t i o n , t h e C i t y o f R o c h e s t e r D e p a r t m e n t o f Community D e v e l o p m e n t and t h e I n d u s t r i a l Management C o u n c i l . The d e v e l o p m e n t o f t h e m e t h o d o l o g y has b e e n made p o s s i b l e t h r o u g h t h e f i n a n c i a l s u p p o r t o f t h e New Y o r k S t a t e D e p a r t m e n t o f E n v i r o n m e n t a l C o n s e r v a t i o n i n 1979 and 1980, and c u r r e n t l y through the U n i t e d S t a t e s E n v i r o n m e n t a l P r o t e c t i o n Agency's

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

6.

YOUNG

ET AL.

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E n v i r o n m e n t a l M o n i t o r i n g Systems L a b i n L a s V e g a s , Nevada ( C o n t r a c t No. 14043 a d m i n i s t e r e d b y L o c k h e e d E n g i n e e r i n g a n d Management S e r v i c e s Company, I n c . ) .

Literature 1. 2.

3.

Cited

N e l s o n , Α. Β., Young, R. A . Proo. Nat'l. Conf. on Management of Uncontrolled Hazardous Waste Sites 1981, p . 52. Legrand, Η. Ε. A Standardized System for Evaluating Waste Disposal Sites: A manual to accompany d e s c r i p t i o n and rating c h a r t s ; N a t i o n a l Water Well A s s o c i a t i o n 1980. Kufs, C . , T w e d e l l , D., P a i g e , S . , W e t z e l , R., Spooner, P., and Colonna, R. Proc. U. S. EPA National Conf. on Management of Uncontrolled Hazardous Waste Sites 1980, p . 31.

RECEIVED

June 16, 1982

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

7 Monitoring to Support Risk Assessments at Hazardous Waste Sites GLENN E. SCHWEITZER U.S. Environmental Protection Agency, Environmental Monitoring Systems Laboratory, Las Vegas, NV 89114 The classical approaches to m u l t i m e d i a monitoring a t h a z a r d o u with examples fro types of monitoring d a t a t h a t a r e most useful i n risk a s s e s s m e n t s a r e d i s c u s s e d in t e r m s o f feasibility, costs, and t i m e for acquisition. Required emphases f o r assessing e n v i r o n m e n t a l h o t s p o t s and for d e t e r m i n i n g long-term habitability of a larger area are described. Special attention is directed to g e o p h y s i c a l t e c h n i q u e s , biological monitoring, and t h e triple s t a g e q u a d r u p o l e mass s p e c t r o m e t e r .

I n r e c e n t y e a r s e n v i r o n m e n t a l m o n i t o r i n g a c t i v i t i e s have been u n d e r t a k e n a t h u n d r e d s o f h a z a r d o u s w a s t e s i t e s t h r o u g h o u t t h e c o u n t r y . W h i l e some o f t h e s e e f f o r t s d a t e back a decade o r more, most o f t h e m o n i t o r i n g h a s been i n i t i a t e d d u r i n g t h e p a s t s e v e r a l years i n a n t i c i p a t i o n of o r i n response t o Governmental r e g u l a t o r y a c t i o n s a t t h e n a t i o n a l , s t a t e , and l o c a l l e v e l s . O f t e n t h e m o n i t o r i n g h a s b e e n t a r g e t e d o n one, two, o r a s m a l l number o f c h e m i c a l s . I n o t h e r c a s e s t h e 129 p r i o r i t y p o l l u t a n t s have been t h e s u b j e c t o f i n v e s t i g a t i o n s . I n a few c a s e s a v a r i e t y o f a n a l y t i c a l methods have been u s e d i n e f f o r t s t o i d e n t i f y and measure s t i l l l a r g e r numbers o f p o s s i b l e e n v i r o n mental containments. As i n d i c a t e d i n F i g u r e 1, a l l e n v i r o n m e n t a l m e d i a where p o l l u t a n t s c o u l d l o d g e h a v e been o f i n t e r e s t , i n c l u d i n g a i r , s u r f a c e w a t e r a n d s e d i m e n t , s o i l , a n d g r o u n d w a t e r . The e n v i r o n m e n t a l pathways o f g r e a t e s t c o n c e r n o b v i o u s l y v a r y f r o m s i t e t o site. F i g u r e 2 summarizes t h e media o f p r i n c i p a l i n t e r e s t a t n i n e " t y p i c a l " s i t e s s e l e c t e d f r o m a n EPA s u r v e y o f 160 s i t e s . I n a d d i t i o n , man-made p a t h w a y s f o r p o l l u t a n t s h a v e t a k e n o n new s i g n i f i c a n c e — sewage a n d d r i n k i n g w a t e r s y s t e m s , i r r i g a t i o n a n d d r a i n a g e systems, and c u t and f i l l a c t i v i t i e s . E v e n measurements

0097-6156/82/0204-0073$06.00/0 © 1982 American Chemical Society

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

Downward Movement in Soil Moisture

Leachate

77u

Direct Human Exposure: Via Dermal Contact & Inhalation

Gaseous & Airborne Particles

Figure 1.

Exposure pathways.

Indirect Human Exposure: Deposition on Crops & Ingestion-Bioaccumulation in Grazing Animals

Recharge to Stream

Human Exposure: Recreation Contact & Water Supply

Deposition

Figure 2. Case studies of typical inactive sites. (Reproduced from Réf. 1.)

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In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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of i n d o o r a i r q u a l i t y and basement sump c o n t a m i n a t i o n have been l i n k e d t o waste s i t e problems. Remote m o n i t o r i n g t e c h n i q u e s have been u s e d t o complement conventional environmental monitoring a c t i v i t i e s . The u s e o f c u r r e n t and a r c h i v a l a e r i a l p h o t o g r a p h y and m u l t i s p e c t r a l o v e r head i m a g e r y t o u n c o v e r and d e l i n e a t e w a s t e s i t e p r o b l e m s h a s e x p a n d e d c o n s i d e r a b l y . A l s o , g r o u n d p e n e t r a t i n g remote s e n s i n g t e c h n o l o g i e s a r e being used t o d e l i n e a t e the s u b s u r f a c e d i s t r i b u t i o n o f w a s t e m a t e r i a l s and t o h e l p t a r g e t m o n i t o r i n g a c t i v i ties. I n a d d i t i o n , t h e s e g e o p h y s i c a l t e c h n o l o g i e s have been shown t o o f f e r p r o m i s e f o r d e t e c t i n g u n d e r g r o u n d movement o f p o l l u t i o n plumes. B i o l o g i c a l m o n i t o r i n g h a s o c c a s i o n a l l y been c o n d u c t e d a t hazardous waste s i t e s t o c l a r i f y p o s s i b l e food c h a i n problems. Food c r o p s , l i v e s t o c k , concern. In addition, have been s a m p l e d t o f i n d i n d i c a t i o n s o f l o c a l c o n t a m i n a t i o n problems. I n s h o r t , t h e l a r g e number of m u l t i - c h e m i c a l , m u l t i - m e d i a e n v i r o n m e n t a l measurements a s s o c i a t e d w i t h h a z a r d o u s w a s t e i n v e s t i g a t i o n s d u r i n g t h e p a s t few y e a r s a r e u n p r e c e d e n t e d i n s c o p e and c o m p l e x i t y . The s m a l l community o f s p e c i a l i s t s i n t h e measurements f i e l d i s b e i n g pushed t o t h e l i m i t t o r e d u c e t h e t i m e and c o s t i n v o l v e d i n s u c h measurements and t o i m p r o v e t h e r e p r e s e n t a t i v e n e s s o f t h e d a t a t h a t a r e c o l l e c t e d and t h e a c c u r a c y of t h e d a t a t h a t a r e r e p o r t e d . R e l a t i n g M o n i t o r i n g Data t o R i s k s M o n i t o r i n g a c t i v i t i e s h a v e u s u a l l y been c a r r i e d o u t t o h e l p c l a r i f y the r i s k s , i f any, a s s o c i a t e d w i t h s p e c i f i c s i t e s . While e v e r y d a t a p o i n t t h a t c o u l d be o b t a i n e d may be o f some i n t e r e s t , the c h a l l e n g e i s t o maximize t h e u s e f u l n e s s f o r r i s k assessment of m o n i t o r i n g d a t a t h a t a r e c o l l e c t e d and a n a l y z e d w i t h i n c o s t and t i m e c o n s t r a i n t s . U n f o r t u n a t e l y , h e a l t h assessment s p e c i a l i s t s h a v e p r o v i d e d l i t t l e g u i d a n c e t o d a t e as t o t h e t y p e o f m o n i t o r i n g i n f o r m a t i o n t h a t w o u l d be most u s e f u l t o them i n determining r i s k s to i n d i v i d u a l s or to larger populations. One a p p r o a c h t o r e l a t i n g m o n i t o r i n g a t a h a z a r d o u s w a s t e s i t e t o r i s k assessment i s s i m p l y t o determine whether e x i s t i n g a i r o r water q u a l i t y standards a r e b e i n g exceeded i n the v i c i n i t y of t h e s i t e a n d w h e t h e r s u c h e x c e s s e s a r e due t o t h e p r e s e n c e o f the s i t e . W i t h r e g a r d t o g r o u n d w a t e r , Maximum C o n t a m i n a n t L e v e l s (MCLs) e s t a b l i s h e d f o r d r i n k i n g w a t e r h a v e been s u g g e s t e d a s surrogate standards. A p r i n c i p a l drawback i n t h i s approach i s t h a t s t a n d a r d s a n d MCLs e x i s t f o r o n l y a f e w c h e m i c a l s . Another o b v i o u s d e f i c i e n c y i s t h a t when a s t a n d a r d h a s been e x c e e d e d , i t may be t o o l a t e f o r e f f e c t i v e r e m e d i a l a c t i o n . A s e c o n d t y p e o f a p p r o a c h i s t o compare c o n t a m i n a t i o n l e v e l s i n t h e media o f i n t e r e s t n e a r t h e s i t e w i t h p o l l u t i o n l e v e l s i n

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

7.

SCHWEITZER

Monitoring to Support Assessments

11

t h e same m e d i a i n c o n t r o l a r e a s . Of s p e c i a l i n t e r e s t w o u l d be a c o n t r o l a r e a n e a r t h e w a s t e s i t e — b u t i n s u l a t e d by g e o g r a p h i c f e a t u r e s from the d i r e c t i n f l u e n c e of the s i t e . T h i s area would be i m p a c t e d b y a l l o f t h e i n d u s t r i a l e m i s s i o n s and e f f l u e n t s t h a t p e r m e a t e t h e r e g i o n as w e l l as o t h e r common s o u r c e s o f c o n t a m i n a t i o n such as a g r i c u l t u r a l c h e m i c a l s . Thus, i n comparing t h e contamination near the s i t e w i t h the contamination i n the c o n t r o l a r e a , i t s h o u l d be p o s s i b l e t o a t t r i b u t e a n y h i g h e r l e v e l s o f contaminants found near t h e s i t e t o the i n f l u e n c e of the s i t e i t s e l f and n o t t o t h e b a c k g r o u n d c h a r a c t e r i s t i c s o f t h e r e g i o n . A s e c o n d t y p e o f c o n t r o l c o u l d be p r o v i d e d by n a t i o n a l b a s e l i n e data. Such d a t a i n d i c a t i n g t h e l e v e l s o f a m b i e n t o r b a c k g r o u n d c o n t a m i n a t i o n u s u a l l y e n c o u n t e r e d i n d i f f e r e n t t y p e s o f demographic s e t t i n g s could help c l a r i f y the s i g n i f i c a n c e of e n v i r o n m e n t a l measurements n e a The c l a s s i c a l a p p r o a c i n d i v i d u a l c h e m i c a l s and t h e n e s t i m a t i n g t h e r e l a t e d r i s k s t o s e n s i t i v e p o p u l a t i o n s through a combination of modeling, m o n i t o r i n g , a n d t o x i c o l o g i c a l e v a l u a t i o n does n o t a p p e a r v e r y p r o m i s i n g . U s u a l l y t h e r e a r e t o o many c h e m i c a l s and c h e m i c a l m i x t u r e s i n v o l v e d , t o o many u n c e r t a i n t i e s i n e s t i m a t i n g c h e m i c a l f a t e and t r a n s p o r t and h e n c e t h e r i s k s t o f u t u r e g e n e r a t i o n s , and t o o many unknown c o n c e r n i n g f u t u r e s i t e c o n t a m i n a n t f a i l u r e s t o g i v e much credence t o such approaches. S t i l l , i n cases i n v o l v i n g h i g h l y t o x i c c h e m i c a l s such as d i o x i n c o n t a m i n a t i o n , d e t a i l e d a n a l y s i s of t h e p r e s e n c e a n d l i k e l y e n v i r o n m e n t a l b e h a v i o r o f s u c h i n d i v i d u a l c h e m i c a l s may be i m p o r t a n t , and m o n i t o r i n g c a p a b i l i t i e s t o d e t e c t and measure t h e p r e s e n c e o f s u c h c h e m i c a l s a t l o w c o n c e n t r a t i o n s w i l l be c r i t i c a l . F i n a l l y , s e v e r a l r a n k i n g s y s t e m s h a v e been d e v e l o p e d f o r p r i o r i t i z i n g t h e r e l a t i v e h a z a r d s a t a l a r g e number o f s i t e s . T h i s a p p r o a c h u s u a l l y i n v o l v e s a w e i g h t i n g of t h e amount a n d c o m p o s i t i o n of hazardous m a t e r i a l a t each s i t e , the contaminant c h a r a c t e r i s t i c s of t h e s i t e , t h e p o t e n t i a l m i g r a t i o n p a t h w a y s , and t h e p r o x i m i t y o f e n v i r o n m e n t a l o r human p o p u l a t i o n s . Variat i o n s o f t h i s a p p r o a c h h a v e a l r e a d y been a p p l i e d many t i m e s , e i t h e r i n a q u a s i - r i g o r o u s f a s h i o n o r i n a more g e n e r a l manner, as s t a t e and l o c a l a u t h o r i t i e s a r e f a c e d w i t h d e c i d i n g where t o concentrate l i m i t e d resources. The

G e n e r a l A p p r o a c h t o S a m p l i n g and A n a l y s i s

Monitoring a c t i v i t i e s involve several interrelated steps: — D e c i d i n g where and how t o t a k e r e p r e s e n t a t i v e s a m p l e s o f t h e m e d i a o f i n t e r e s t and how t o h a n d l e t h e s a m p l e s en r o u t e t o the a n a l y t i c a l l a b o r a t o r i e s . — S e l e c t i n g a n a l y t i c a l methods t o i n v e s t i g a t e t h e p r e s e n c e o r a b s e n c e o f e i t h e r a f i n i t e o r open ended l i s t o f c h e m i c a l s .

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— C h o o s i n g a p r o c e d u r e and f o r m a t f o r a g g r e g a t i n g and p r e s e n t i n g t h e r e s u l t s of t h e a n a l y s i s and f o r s e t t i n g f o r t h t h e d e g r e e of c o n f i d e n c e i n t h e d a t a . — D e t e r m i n i n g how t o i n t e r p r e t t h e m o n i t o r i n g d a t a as t o p r e s e n c e , q u a n t i t y , t r a n s f o r m a t i o n , and m i g r a t i o n o f t h e c h e m i c a l s of i n t e r e s t . We a r e r a p i d l y a c q u i r i n g e x p e r i e n c e i n a l l of t h e s e a r e a s . Over t h e y e a r s many manuals h a v e been p r e p a r e d by a number o f g r o u p s on s a m p l i n g and a n a l y t i c a l methods. S a m p l i n g d e s i g n i s u s u a l l y s i t e - s p e c i f i c , and s o m e t i m e s c h e m i c a l - s p e c i f i c , and c a s e s t u d i e s o f d i f f e r e n t a p p r o a c h e s t h a t have been u s e d i n t h e p a s t are p a r t i c u l a r l y i n s t r u c t i v e i n p r o v i d i n g f u t u r e guidance i n t h i s a r e a . However, w i t h r e g a r d t o t h e p r e s e n t a t i o n and i n t e r p r e t a t i o n of d a t a , we h a v e o n l y begun t o d e v e l o p u s e f u l a p p r o a c h e s f o r r e l a t i n g monitoring dat t risks—th thrust f thi symposium A few of t h e l e s s o n m o n i t o r i n g programs a r 1. A t t h e o u t s e t t h e o b j e c t i v e s of t h e m o n i t o r i n g p r o g r a m s h o u l d be c l e a r l y d e f i n e d . M o n i t o r i n g programs can be h e l p f u l b o t h i n i d e n t i f y i n g h o t s p o t s o f n e a r t e r m c o n c e r n and i n a s s e s s i n g t h e l o n g e r t e r m h a b i t a b i l i t y o f t h e a r e a . E a c h of t h e s e o b j e c t i v e s may r e q u i r e a d i f f e r e n t p r o g r a m o r i e n t a t i o n , h o w e v e r , as shown i n F i g u r e 3. U s u a l l y b o t h o b j e c t i v e s w i l l be i m p o r t a n t i n v a r y i n g d e g r e e s , and t h e p r o g r a m e m p h a s i s s h o u l d be a d j u s t e d accordingly. P r i o r to i n i t i a t i n g the m o n i t o r i n g program, the u s e r s of t h e m o n i t o r i n g d a t a s h o u l d be s a t i s f i e d t h a t t h e d a t a w i l l be c o l l e c t e d , a n a l y z e d , and p r e s e n t e d i n a manner w h i c h i s r e s p o n s i v e to t h e i r needs. 2. S e v e r a l f a c t o r s are important i n s e l e c t i n g the i n d i v i d u a l c h e m i c a l s of s p e c i a l i n t e r e s t . For example, c e r t a i n c h e m i c a l s may have been d e p o s i t e d a t t h e s i t e i n v e r y l a r g e q u a n t i t i e s , and t h e r e f o r e t h e y a r e of p r i n c i p a l c o n c e r n s i m p l y b e c a u s e o f t h e i r v o l u m e . S e c o n d l y , one o r more of t h e c h e m i c a l s known t o be p r e s e n t a t t h e s i t e may be so t o x i c t h a t t h e p o t e n t i a l t h r e a t e v e n a t low v o l u m e s i s o b v i o u s l y a m a j o r c o n c e r n (e.g., d i o x i n ) . C e r t a i n " i n d i c a t o r " c h e m i c a l s commonly f o u n d a t w a s t e s i t e s may behave i n t h e e n v i r o n m e n t i n a manner c h a r a c t e r i s t i c of many o t h e r c h e m i c a l s as w e l l ( e . g . g r o u p s o f p e s t i c i d e s ) , and d e t e r m i n i n g t h e e n v i r o n m e n t a l d i s t r i b u t i o n of s u c h " i n d i c a t o r " c h e m i c a l s c o u l d be i n d i c a t i v e o f b r o a d e r c o n t a m i n a t i o n p r o b l e m s . A n a l y s i s of l e a c h a t e f r o m t h e edge o f t h e s i t e o r p r e l i m i n a r y m o n i t o r i n g c l o s e t o the s i t e might i d e n t i f y c h e m i c a l s t h a t are e s c a p i n g from the s i t e . F i n a l l y , sampling f o r a group of c h e m i c a l s w h i c h a r e u s u a l l y a n a l y z e d as a p a c k a g e s u c h as t h e 129 p r i o r i t y p o l l u t a n t s m i g h t r e s u l t i n c o n s i d e r a b l e s a v i n g s p e r c h e m i c a l i n a n a l y t i c a l c o s t s . A l l of t h e s e f a c t o r s s h o u l d h a v e a b e a r i n g on t h e s e l e c t i o n of t h e c h e m i c a l s f o r i n t e n s i v e i n v e s tigation. 3. S t a t i s t i c a l a s p e c t s a r e an i m p o r t a n t f a c t o r i n t h e d e s i g n of a m o n i t o r i n g p r o g r a m t h a t i s t o p r o v i d e r e p r e s e n t a t i v e

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982. Many chemicals including degradation products All levels including trace levels Past, current, and future leakages Also, soil, sediment, biota, surface water, sewers, groundwater Entire population Document highest and median concentration levels in individual media and compare such levels with control areas General multimedia sampling of broad areas with bias toward natural and man-made pathways from the site. Concurrent monitoring in nearby control areas. Monitor along entire environmental pathway.

High toxicity chemicals suspected to be in area "High" levels Past and current leakages at site Air, drinking water, food Susceptible individuals near hot spots Determine highest intergrated exposure levels for specific groups of individuals Limited multimedia sampling of broad areas and intensive single media monitoring of suspected hot spots near populations. Emphasize monitoring at interface of receptor.

Chemicals of concern

Levels of concern

Likely sources

Pathways of primary concern

Populations of concern

Assessment emphasis

Monitoring approach

Assessing exposures near uncontrolled sites.

Determine long term habitability of area

Identify near term exposure problems

Objective

Figure 3.

Assessing Chemical Saturation

Assessing Hot Spots

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data. A s t a t i s t i c i a n on t h e p l a n n i n g team c a n h e l p i n s u r e t h a t adequate c o n s i d e r a t i o n i s g i v e n t o these aspects both i n d e s i g n i n g t h e p r o g r a m and i n f o r m a t t i n g and i n t e r p r e t i n g d a t a . A photo i n t e r p r e t e r c a n a l s o be a n i m p o r t a n t member o f t h e p l a n n i n g team, b o t h i n s e l e c t i n g m o n i t o r i n g s i t e s and i n d e s i g n i n g t h e a p p r o a c h for relating concentration levels to population a c t i v i t i e s . 4. B e f o r e any s a m p l e s a r e t a k e n , a c o m p l e t e s a m p l i n g p l a n s h o u l d be d e v e l o p e d w i t h b u i l t - i n c h e c k p o i n t s f o r a d j u s t i n g t h e p l a n as sampling r e s u l t s a r e o b t a i n e d . D e v i a t i o n s from the p l a n s h o u l d be r e s i s t e d o t h e r t h a n t o a d j u s t t h e p l a n i n r e s p o n s e t o unexpected data r e s u l t s . As a r u l e o f thumb, on t h e o r d e r o f f i f t e e n p e r c e n t o f t h e s a m p l i n g m i g h t be f o r s c r e e n i n g t o h e l p c l a r i f y h y p o t h e s e s a s t o p o s s i b l e g r a d i e n t s and h o t s p o t s a r o u n d the s i t e s , s e v e n t y p e r c e n t d i r e c t e d t o i n v e s t i g a t i n g t h e h y p o t h e s e s , and f i f t e e t d f o supplementar sampling of n e g l e c t e d area p r o g r a m . The s a m p l i n g schem provision confirm o r r e j e c t p r e v i o u s l y reported f i n d i n g s of a c o n t r o v e r s i a l nature. Access t o p r e f e r r e d sampling s i t e s i s not always possible. The s a m p l i n g p l a n s h o u l d be s u f f i c i e n t l y f l e x i b l e t o compensate f o r s u c h p r o b l e m s . 5. A q u a l i t y a s s u r a n c e program i n v o l v i n g s u r r o g a t e r e c o v e r i e s , i n t e r and i n t r a l a b o r a t o r y d u p l i c a t e s , and f i e l d and laboratory blanks i s e s s e n t i a l . E a c h d a t a p o i n t s h o u l d be i n d i v i d u a l l y v a l i d a t e d a s a c c e p t a b l e d a t a , and p r e c i s i o n and a c c u r a c y d a t a s h o u l d be d e v e l o p e d f o r e a c h d a t a s e t . The q u a l i t y a s s u r a n c e p r o g r a m may a c c o u n t f o r 10 t o 20 p e r c e n t o f t h e m o n i t o r i n g c o s t s . S p e c i a l e f f o r t s a r e needed t o m i n i m i z e h o l d i n g t i m e s between s a m p l i n g and a n a l y s i s . However, e x t e n d e d h o l d i n g t i m e s beyond t h e u s u a l t a r g e t o f two weeks may be u n a v o i d a b l e . I n t h a t event a p p r o p r i a t e storage procedures a r e p a r t i c u l a r l y important t o prevent e x c e s s i v e decay o f t h e samples. A l s o , c o n t a m i n a n t s a s s o c i a t e d w i t h t h e s a m p l i n g and a n a l y t i c a l t e c h n i q u e s a r e o f t e n d i f f i c u l t t o a v o i d , and d a t a s u s p e c t e d o f s u c h c o n t a m i n a t i o n s h o u l d be c o n s i d e r d f o r d i s c a r d i n g . Of p a r t i c u l a r c o n c e r n , f o r e x a m p l e , a r e benzene and t o l u e n e c o n t a m i n a t i o n when u s i n g T e n a x t r a p s , m e t h y l e n e c h l o r i d e and phthalates that a r e present i n l a b o r a t o r i e s , isophorone which can be a d e r i v a t i v e o f t h e l a b o r a t o r y s o l v e n t a c e t o n e , and t h e h i g h pH i n g r o u n d w a t e r a s s o c i a t e d w i t h g r o u t i n g o f s a m p l i n g w e l l s w h i c h may r e s u l t i n a r t i f a c t s b e i n g o b s e r v e d . 6. D a t a f o r m a t t i n g and p r e s e n t a t i o n c a n h a v e a s i g n i f i c a n t i m p a c t on t h e i n t e r p r e t a t i o n o f t h e d a t a . P l o t t i n g each data p o i n t on a map i s p r o b a b l y t h e s a f e s t way t o i n s u r e a t o t a l l y o b j e c t i v e p r e s e n t a t i o n o f f i n d i n g s . M o n i t o r i n g d a t a may n o t provide a d e f i n i t e p o r t r a y a l of p o l l u t a n t gradients or p o l l u t i o n p a t t e r n s b u t may o n l y be s u g g e s t i v e o f g e n e r a l p o l l u t a n t distribution. I n t e r p r e t a t i o n s o f t h e d a t a may be c o n t r o v e r s i a l , and e f f o r t s s h o u l d be made t o i s o l a t e c r i t i c i s m s o f t h e i n t e r p r e tations.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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These and o t h e r l e s s o n s l e a r n e d s e t an i m p o r t a n t f r a m e w o r k f o r our r e s e a r c h e f f o r t s t o improve m o n i t o r i n g c a p a b i l i t i e s . D i s c u s s e d b e l o w a r e t h r e e a r e a s of c u r r e n t r e s e a r c h i n t e r e s t . Geophysical

Techniques

The i n c r e a s i n g i m p o r t a n c e of g e o p h y s i c a l i n v e s t i g a t i o n s has been r e p e a t e d l y documented i n r e c e n t months. The most commonly u s e d t e c h n i q u e s have been s e i s m i c r e f r a c t i o n , g r o u n d p e n e t r a t i n g r a d a r , e l e c t r i c a l c o n d u c t i v i t y , and magnetometer s u r v e y s . Figure 4 p r e s e n t s a c o m p a r i s o n of an a n a l y s i s of d a t a f r o m 16 g r o u n d w a t e r s a m p l i n g w e l l s w i t h an a n a l y s i s of e l e c t r o m a g n e t i c d a t a i n d e t e r m i n i n g plume f l o w . F i g u r e 5 u n d e r s c o r e s how c o n d u c t i v i t y d a t a m i g h t h a v e been u s e d t o i m p r o v e t h e l o c a t i o n of s a m p l i n g wells. F i n a l l y , Figur geophysical i n v e s t i g a t i o n E f f o r t s have a l s o been i n i t i a t e d t o i n s t r u m e n t new s i t e s w i t h e l e c t r o d e systems f o r d e t e c t i n g l e a c h a t e leakage through the l i n e r s of t h e s i t e s . One a p p r o a c h i s t o s u r r o u n d t h e s i t e w i t h r e s i s t i v i t y s o u n d i n g s t a t i o n s u s i n g t h e e a r t h as t h e c o n d u c t i n g medium. A n o t h e r a p p r o a c h has been t o embed a w i r e g r i d j u s t below the s i t e . I n e i t h e r c a s e , changes i n r e s i s t i v i t y m e a s u r e ments w o u l d s i g n a l a p o s s i b l e l e a c h a t e plume m i g r a t i n g downward from the s i t e . W h i l e t h i s t e c h n i q u e seems v e r y a p p e a l i n g , c o n s i d e r a b l e proof t e s t i n g i s i n order g i v e n the n e c e s s i t y f o r s y s tems t h a t w i l l m i n i m i z e f a l s e a l a r m s and w i l l o p e r a t e r e l i a b l y f o r many d e c a d e s . Another promising approach c a l l s f o r combining l a s e r - i n d u c e d f l u o r e s c e n c e t o i n d i c a t e p o l l u t a n t c o n t a m i n a t i o n of an aqueous body, and i n t h i s c a s e g r o u n d w a t e r , w i t h f i b e r o p t i c t e c h n i q u e s f o r e n t e r i n g the e a r t h through v e r y s m a l l diameter w e l l s ( l e s s t h a n one i n c h ) . This approach i s p a r t i c u l a r l y a t t r a c t i v e i n a t t e m p t i n g t o measure T o t a l O r g a n i c C a r b o n (TOC) a s a s u r r o g a t e f o r t h e p o l l u t i o n plume. I n d e e d , a p r i n c i p a l r e s e a r c h d i r e c t i o n i s d e m o n s t r a t i n g t h e f e a s i b i l i t y of TOC measurements w h i l e s e a r c h i n g f o r a d d i t i o n a l p o l l u t i o n s i g n a t u r e s t h a t c o u l d be d e t e c t e d by l a s e r f l u o r e s c e n c e . I f t h e method p r o v e s o p e r a t i o n a l l y f e a s i b l e , reductions i n w e l l diameters should r e s u l t i n considerable cost savings. Improved A n a l y t i c a l Methods As more p o t e n t i a l l y h a r m f u l c h e m i c a l s a r e d i s c o v e r e d , c o n c e r n f o r t h e l o n g - t e r m i m p a c t of low c o n c e n t r a t i o n s of l a r g e numbers of h a z a r d o u s e l e m e n t s and compounds i n c r e a s e s . The need f o r i m p r o v e d methods f o r a n a l y z i n g e n v i r o n m e n t a l s a m p l e s t o i d e n t i f y and measure v e r y s m a l l amounts of a w i d e v a r i e t y of c h e m i c a l s becomes c r i t i c a l . A number of a d v a n c e d methods f o r a n a l y z i n g e n v i r o n m e n t a l s a m p l e s a r e u n d e r i n v e s t i g a t i o n by r e s e a r c h e r s i n many

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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Values in Millimhos/Meter

Figure 4. Monitor well measurements and electromagnetic measurements at same site. Top: potentiometric contours showing plume flow. Bottom: conductivity contours showing plumeflow.(Reproduced from Ref. 2.)

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

SCHWEITZER

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Figure 5. Conductivity data showing buried hazardous materials. Key: · , wells drilled before conductivity data were available. (Reproduced from Ref. 2.)

Alternative

Informational Needs

Removal of Buried Drums and Chemicals

Drum Condition, Number, and Contents Trench Location and Geometry

Encapsulation of Source

Drum Contents Imperviousness of Underlying Strata Level of Subsurface Contamination Trench Location and Geometry

Collection and Treatment of Leachate

Areal Extent of Contamination Type of Contamination Concentration of Contaminants Imperviousness of Underlying Strata Aquifier Characteristics

No Action

Drum Contents and Condition Level of Subsurface Contamination Type of Contamination

Figure 6.

Informational needs for implementation of abatement activities. (Reproduced from Réf. 1.)

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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laboratories. Of p a r t i c u l a r r e l e v a n c e t o t h e p r o b l e m s of hazardous wastes are the a p p l i c a t i o n of fused s i l i c a c a p i l l a r y columns i n GC/MS s y s t e m s , F o u r i e r t r a n s f o r m i n f r a r e d s p e c t r o s c o p y , and n o n - e x t r a c t i v e m u l t i - e l e m e n t a l a n a l y s i s . P r e s e n t MS t e c h n i q u e s f o r a n a l y s i s of o r g a n i c compounds i n c o m p l e x s a m p l e s r e q u i r e s e p a r a t i o n of t h e sample components p r i o r t o MS a n a l y s i s . The s e p a r a t i o n i s u s u a l l y a c c o m p l i s h e d by e x t r a c t i n g the samples, s e p a r a t i n g the e x t r a c t s i n t o s e v e r a l f r a c t i o n s ( c l e a n u p ) , and a n a l y z i n g t h e f r a c t i o n s by GC/MS. These s t e p s , e s p e c i a l l y t h e s a m p l e p r e p a r a t i o n and c l e a n u p , a r e t i m e c o n s u m i n g and e x p e n s i v e . The use of tandem mass s p e c t r o m e t e r s can e l i m i n a t e t h e sample p r e p a r a t i o n s t e p s and p r o v i d e i m p r o v e d c a p a b i l i t i e s f o r MS analysis. One s y s t e m , t h e t r i p l e q u a d r u p o l e mass s p e c t r o m e t e r , u s e s a c o m b i n a t i o n of t h r e i o n i z e , s e p a r a t e , and a n a l y z s a m p l e p r e p a r a t i o n as shown i n F i g u r e s 7 and 8. The sample components a r e i o n i z e d and s e p a r a t e d a c c o r d i n g t o t h e i r massto-charge r a t i o i n the f i r s t quadrupole. This step corresponds t o t h e GC s t e p i n GC/MS. I n t h e s e c o n d q u a d r u p o l e t h e s e i o n s c o l l i d e w i t h an i n e r t gas and f r a g m e n t ( c h e m i c a l i o n i z a t i o n ) . In t h e t h i r d q u a d r u p o l e t h e f r a g m e n t s a r e i d e n t i f i e d (mass analyzer). T r i p l e q u a d r u p o l e mass s p e c t r o m e t r y can p r o v i d e r a p i d s c r e e n i n g of c o m p l e x m i x t u r e s f o r s p e c i f i c compounds and can be u s e d t o a n a l y z e f o r compounds t h a t c a n n o t r o u t i n e l y be a n a l y z e d by GC/MS. I n a d d i t i o n , s t r u c t u r a l i n f o r m a t i o n can be o b t a i n e d f o r c e r t a i n t y p e s of compounds s i n c e i n c o l l i s i o n - i n d u c e d d i s s o c i a t i o n s t h e f r a g m e n t s a r e l i k e l y t o show t h e s t r u c t u a l d i f f e r e n c e s of t h e p a r e n t compounds. Complex m i x t u r e s h a v e been a n a l y z e d by t h i s t e c h n i q u e by i n t r o d u c i n g t h e sample d i r e c t l y i n t o t h e h e a t e d s a m p l e p o r t of t h e i n s t r u m e n t w i t h l i t t l e o r no sample p r e t r e a t m e n t . T r i p l e q u a d r u p o l e mass s p e c t r o m e t r y p r o m i s e s t o be a u s e f u l , c o s t - e f f e c t i v e , and p r a c t i c a l advanced technique f o r e n v i r o n m e n t a l a n a l y s i s , p a r t i c u l a r l y when a p p l i e d t o h a z a r d o u s w a s t e p r o b l e m s . M o n i t o r i n g i n Animals

and

Plants

As i n d i c a t e d i n F i g u r e 9, many a p p r o a c h e s t o m o n i t o r i n g a n i m a l s p e c i e s at hazardous waste s i t e s have been suggested. A l s o , v e g e t a t i o n m o n i t o r i n g i s commonly p r o p o s e d . V e r y few o f t h e s u g g e s t e d a p p r o a c h e s , h o w e v e r , a r e beyond t h e e a r l y r e s e a r c h s t a g e t o t h e p o i n t where t h e y c o u l d be d e p l o y e d t o p r o v i d e r e l i a b l e data concerning f i e l d contamination. The t y p e s of b i o l o g i c a l methods t h a t need t o be c a r e f u l l y e v a l u a t e d a n d , i f a p p r o p r i a t e , s t a n d a r d i z e d f o r f i e l d use i n c l u d e (1) l a b o r a t o r y s c r e e n i n g t e s t s t o a s s e s s the r e l a t i v e h a z a r d of c h e m i c a l m i x t u r e s , ( 2 ) f i e l d s u r v e y methods t o d e t e c t changes i n b i o l o g i c a l p o p u l a t i o n s , and ( 3 ) m o n i t o r i n g t e c h n i q u e s t o d e t e c t

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

SCHWEITZER

Monitoring to Support Assessments

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

Ionize All Components of Mixture

®

(Mi)

Ionizer Focusing Lenses

Figure 8.

Select a Molecular Ion of Interest, M |

Qi

Quadrupole Mass Filter 2

3

Separate the Fragment Ions A* . . . A* According to Mass

Quadrupole Mass Filter

Triple-stage quadrupole mass spectrometer schematic.

Decompose M | by Collision With Neutral Gas Molecules ( · ) , Transmit All Ions Formed (A|. A+,.. . . Ap) to Mass Filter, Q

Q

Collision Cell

Output to Graphic Display

Detector

7.

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Monitoring to Support Assessments

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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t h e p r e s e n c e of s p e c i f i c compounds i n b i o l o g i c a l m a t e r i a l s . The t h r e e a p p r o a c h e s h a v e s e v e r a l f e a t u r e s i n common. These m e t h o d s , when a p p l i e d w i t h i n a p p r o p r i a t e e x p e r i m e n t a l d e s i g n s , may i n d i c a t e -the s o u r c e of p o l l u t a n t s and p o t e n t i a l l y can i n d i c a t e p o l l u t a n t d i s t r i b u t i o n i n the a i r , water, s o i l , or sediment a t study l o c a t i o n s . E q u a l l y i m p o r t a n t , t h e y can i d e n t i f y t h e e x t e n t of p r o b l e m s , t h e y can p r o v i d e i n f o r m a t i o n u s e f u l f o r h a z a r d e v a l u a t i o n s , and t h e y can f r e q u e n t l y h e l p i d e n t i f y s p e c i f i c p o l l u t a n t s , o r c o m b i n a t i o n s of p o l l u t a n t s , t h a t a r e causing problems. S c r e e n i n g T e s t s . S c r e e n i n g t e s t s can be u s e d d u r i n g i n i t i a l i n v e s t i g a t i o n s a t w a s t e s i t e s t o p r o v i d e a r a p i d a s s e s s m e n t of p o t e n t i a l h a z a r d s t o ( 1 ) f i e l d and l a b o r a t o r y p e r s o n n e l i n v e s t i g a t i n g the s i t e , (2) person s i t e , and ( 3 ) t h e n e a r b s y s t e m s a r e c o n d u c t e d u n d e r c o n t r o l l e d c o n d i t i o n s , u s u a l l y by b r i n g i n g s a m p l e s i n t o t h e l a b o r a t o r y o r by p l a c i n g t e s t o r g a n i s m s a t the s i t e . E x a m p l e s of s c r e e n i n g t e s t s t o c l a r i f y r e l a t i v e p e r s o n n e l h a z a r d s m i g h t i n c l u d e t h e d e t e c t i o n o f mutagens i n body f l u i d s of l a b o r a t o r y a n i m a l s e x p o s e d t o w a s t e s i t e m a t e r i a l and v a r i o u s immunotoxicity responses i n l a b o r a t o r y animals. The d e v e l o p m e n t of b i o l o g i c a l s c r e e n i n g t e s t s has r e c e i v e d much a t t e n t i o n o v e r t h e p a s t few y e a r s , and s e v e r a l t e s t s ( e . g . , t h e Ames t e s t ) h a v e become w i d e l y u s e d by many l a b o r a t o r i e s . Surveys of Environmental Impacts. F i e l d s u r v e y methods f o c u s on a s s e s s i n g changes i n t h e c o n d i t i o n o f e n t i r e p o p u l a t i o n s and e c o l o g i c a l community f u n c t i o n s ( e . g . , p e s t s p e c i e s p r o l i f e r a t i o n , s p e c i e s d i v e r s i t y , l i t t e r d e c o m p o s i t i o n r a t e , changes i n t h e r a t e of p r i m a r y p r o d u c t i o n ) . These methods u n d e r c e r t a i n c i r c u m s t a n c e s may r e l a t e e f f e c t s t o s p e c i f i c p o l l u t a n t s o u r c e s , b u t most f r e q u e n t l y t h e y a r e u s e d t o i n d i c a t e t h a t a p r o b l e m does exist. A c u r r e n t a p p l i c a t i o n o f s u r v e y methods b e i n g d e v e l o p e d e m p h a s i z e s i d e n t i f i c a t i o n of i n d i g e n o u s s p e c i e s t o s e r v e as s u r r o g a t e s f o r a p o r t i o n of t h e e c o s y s t e m . Monitoring f o r Bioaccumulation or B i o e f f e c t s . Biological methods can be u s e d s i m p l y t o i n d i c a t e t h e p r e s e n c e of a p o l l u t a n t at a study l o c a t i o n . C h e m i c a l a n a l y s i s can i d e n t i f y t h e t y p e o f p o l l u t a n t p r e s e n t i n b i o l o g i c a l s p e c i e s as shown i n F i g u r e 10. However, u n l e s s t h e r e i s an e x t e n s i v e d a t a b a s e c o n c e r n i n g u p t a k e r a t e s , s u c h an a p p r o a c h w i l l n o t r e v e a l p o l l u t a n t c o n c e n t r a t i o n s i n the a r e a . B i o l o g i c a l e f f e c t s such as enzyme i n h i b i t i o n can a l s o be u s e d i n some c a s e s t o i n d i c a t e t h e t y p e s of c h e m i c a l s i n t h e a r e a ( e . g . , i n h i b i t i o n o f r e d b l o o d c e l l a c e t y l c h o l i n e s t e r a s e f o l l o w i n g an a n i m a l ' s c o n t a c t w i t h o r g a n o p h o s p h o r u s c h e m i c a l s ) . The d e t e c t i o n of m e t a b o l i c p r o d u c t s i n body f l u i d s m i g h t a l s o be u s e d t o i n v e s t i g a t e t h e b i o l o g i c a l

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982. XXX XXX

XX XX XX

Lead

Mercury

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Figure 10.

xx—Moderate.

XXX

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xxx—High to very high.

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Bioaccumulation and bioconcentration of trace elements.

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u p t a k e of some compounds ( e . g . , t h e p r e s e n c e of c h l o r i n a t e d p h e n o l s i n u r i n e f o l l o w i n g u p t a k e of c h l o r i n a t e d h y d r o c a r b o n s ) . P r o v i d i n g More M e a n i n g f u l M o n i t o r i n g D a t a f o r H e a l t h A s s e s s m e n t s Even w i t h r a p i d a d v a n c e s i n t h e s t a t e - o f - t h e - a r t of m o n i t o r i n g t e c h n o l o g i e s many of t h e p r o b l e m s of e f f e c t i v e l y m e s h i n g m o n i t o r i n g d a t a w i t h d a t a on h e a l t h e f f e c t s w i l l c o n t i n u e t o persist. U n d o u b t e d l y , t h e p a s t a p p r o a c h e s of c o l o c a t i n g m o n i t o r i n g and h e a l t h s t u d i e s w i l l c o n t i n u e . These a p p r o a c h e s r e l y on m o n i t o r i n g a c t i v i t i e s t o c l a r i f y e x p o s u r e s t o s p e c i f i c c h e m i c a l s and on h e a l t h s t u d i e s e i t h e r t o a s s e s s t h e a c c u m u l a t i o n o f t h e s e c h e m i c a l s i n human p o p u l a t i o n s o r t o c l a r i f y t h e h e a l t h e f f e c t s w h i c h c o u l d be r e a s o n a b l y a t t r i b u t e d t o c h e m i c a l e x p o sures. Good e x a m p l e s o i n t h e U n i t e d S t a t e s an cadmium and l e a d b o t h t e x p o s u r e (b) c e r t a i n t y p e s of e x p o s u r e s t o o r g a n i c c h e m i c a l s t o i n c r e a s e d i n c i d e n c e of c a n c e r . O b v i o u s l y , u n c e r t a i n t i e s abound i n s u c h e f f o r t s p a r t i c u l a r l y with regard to characterizing population a c t i v i t y p a t t e r n s o v e r an e x t e n d e d p e r i o d of t i m e as t h e b a s i s for exposure e s t i m a t e s . T u r n i n g more d i r e c t l y t o the i s s u e s s u r r o u n d i n g h a z a r d o u s w a s t e s i t e s , t h e s c i e n t i f i c community has an u n u s u a l o p p o r t u n i t y t o d e v e l o p and a p p l y i m p r o v e d a p p r o a c h e s f o r c o u p l i n g e n v i r o n m e n t a l c h e m i s t r y and t h e h e a l t h s c i e n c e s . W h i l e a n s w e r s may be needed t o d a y , t h e same t y p e s of a n s w e r s w i l l be needed f o r many d e c a d e s . T h u s , we s h o u l d t h i n k i n terms of l o n g - r a n g e r e s e a r c h p r o g r a m s t h a t w i l l p r o v i d e a v a r i e t y of i n t e r i m a n s w e r s — p r o g r a m s t h a t can r e l a t e measurements i n s o i l , w a t e r , a i r , and t h e f o o d c h a i n i n m e a n i n g f u l ways t o n e a r - t e r m and l o n g - t e r m e f f e c t s i n people. F o r e x a m p l e , how can m o n i t o r i n g h e l p us p r e d i c t w i t h some c o n f i d e n c e t h e r a t e s a t w h i c h c h e m i c a l s u n d e r a v a r i e t y of c o n d i t i o n s w i l l migrate toward people? Can a g g r e g a t i o n s o f d a t a on c l a s s e s of c h e m i c a l s d e t e c t e d a t t r a c e l e v e l s p r o v i d e a meaningful basis f o r i n v e s t i g a t i n g p o s s i b l e e f f e c t s ? Can p r a c t i c a l m o n i t o r i n g s y s t e m s be d e v e l o p e d w h i c h p r o v i d e e x p o s u r e d a t a on i n d i v i d u a l s as i s o f t e n done u s i n g f i l m badges and thermoluminescent d o s i m e t e r s i n the r a d i a t i o n f i e l d ? Finally, can measurements of v e r y l o w l e v e l s of c h e m i c a l s o r of t h e e a r l y s t a g e s of b i o c h e m i c a l r e a c t i o n s i n p e o p l e o r a n i m a l s s e r v e as e a r l y w a r n i n g i n d i c a t o r s of a d v e r s e h e a l t h e f f e c t s t h a t c o u l d r e s u l t from f u r t h e r exposures?

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

7.

SCHWEITZER

Monitoring to Support Assessments

91

Literature Cited 1.

"Remedial A c t i o n s at Hazardous Waste S i t e s : Survey and Case S t u d i e s , " United States Environmental P r o t e c t i o n Agency 430/9-81-05.

2.

" N a t i o n a l Conference on Management of U n c o n t r o l l e d Waste Sites," United States Environmental P r o t e c t i o n Agency/ Hazardous Waste M a t e r i a l C o n t r o l Research Institute, October 28, 1981, pp. 86, 87.

RECEIVED

June 16,

1982.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

8 Currently Available Geophysical Methods for Use in Hazardous Waste Site Investigations ROY B. EVANS

U.S. Environmental Protection Agency, Environmental Monitoring Systems Laboratory, Las Vegas, NV 89114 Monitoring to estimate exposure is e s s e n t i a l to risk assessmen - e f f e c t i v e hazardou three phases: (1) p r e l i m i n a r y site assessment, utilizing aerial photography and site i n s p e c t i o n s ; (2) geophysical surveys to p i n p o i n t buried wastes and to help define plumes of conductive contaminants in groundwater; and (3) c o n f i r m a t i o n of groundwater contamination through monitoring w e l l networks designed on the b a s i s of the geo p h y s i c a l survey. C u r r e n t l y a v a i l a b l e g e o p h y s i c a l methods most a p p l i c a b l e in hazardous waste site investigations i n c l u d e metal detectors and magnetometers ( u s e f u l in l o c a t i n g buried wastes); groundpenetrating radar ( u s e f u l in d e f i n i n g trench boundaries); electromagnetic i n d u c t i o n or EM (useful in surveys of shallow plumes of conductive groundwater contaminants); resistivity (useful i n surveys of site s t r a t i g r a p h y and deep groundwater contaminant plumes); and seismic methods (most u s e f u l in surveying geologic s t r a t i g r a p h y ) . M o n i t o r i n g i s u s u a l l y an e s s e n t i a l p a r t of r i s k assessment; e n v i r o n m e n t a l samples a r e c o l l e c t e d i n v a r i o u s media n e a r s o u r c e s o f p o t e n t i a l e x p o s u r e , and t h e s e s a m p l e s a r e a n a l y z e d f o r t o x i c substances suspected of being present. In the past, i n v e s t i g a t i o n o f h a z a r d o u s waste s i t e s h a s commonly depended upon d r i l l i n g t o o b t a i n i n f o r m a t i o n o n t h e g e o l o g i c s e t t i n g , upon m o n i t o r i n g w e l l s f o r s a m p l e s o f g r o u n d w a t e r , and upon l a b o r a t o r y a n a l y s i s o f s o i l and w a s t e s a m p l e s . D u r i n g t h e p a s t d e c a d e , e x t e n s i v e d e v e l o p m e n t i n remote s e n s i n g g e o p h y s i c a l e q u i p m e n t , f i e l d methods, a n a l y t i c a l t e c h n i q u e s , and a s s o c i a t e d computer p r o c e s s i n g h a s g r e a t l y i m p r o v e d o u r a b i l i t y t o c h a r a c t e r i z e hazardous waste s i t e s . Some g e o p h y s i c a l methods o f f e r a d i r e c t means o f d e t e c t i n g c o n t a m i n a n t p l u m e s , f l o w 0097-6156/82/0204-0093$06.25/0 © 1982 American Chemical Society

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

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d i r e c t i o n , and b u r i e d drums. Some a r e a p p l i c a b l e t o measurements o f c o n t a m i n a n t s and d i r e c t i o n o f f l o w w i t h i n t h e v a d o s e z o n e ; o t h e r s o f f e r a way t o o b t a i n d e t a i l e d i n f o r m a t i o n a b o u t s u b s u r f a c e g e o l o g y . The c a p a b i l i t y t o c h a r a c t e r i z e t h e subsurface r a p i d l y without d i s t u r b i n g the s i t e o f f e r s b e n e f i t s i n t e r m s o f l e s s c o s t , l e s s r i s k , and b e t t e r u n d e r s t a n d i n g o f site conditions. C o s t - e f f e c t i v e d e s i g n o f h a z a r d o u s waste s i t e g r o u n d w a t e r i n v e s t i g a t i o n s i n v o l v e s an i n t e g r a t e d , t h r e e - p h a s e d a p p r o a c h : (1) p r e l i m i n a r y s i t e assessment, i n v o l v i n g t h e use o f a e r i a l p h o t o g r a p h y , o n - s i t e i n s p e c t i o n s , and r e a d i l y a v a i l a b l e i n f o r m a t i o n t o a p p r o x i m a t e s i t e b o u n d a r i e s and l o c a t i o n s o f w a s t e c o n c e n t r a t i o n s , a s w e l l as p r o b a b l e s i t e g e o l o g y ; ( 2 ) g e o p h y s i c a l s u r v e y s t o p i n p o i n t b u r i e d w a s t e s and e s t i m a t e q u a n t i t i e s , and t o d e l i n e a t e plumes o f c o n d u c t i v e c o n t a m i n a n t s i n g r o u n d w a t e r ; and ( 3 contamination through monitorin b a s i s o f plumes and s u b s u r f a c e s t r a t i g r a p h y d e f i n e d by t h e geophysical surveys. The s p a t i a l c h a r a c t e r i z a t i o n o f t h e s i t e by g e o p h y s i c a l means c a n make p o s s i b l e t h e e f f i c i e n t l o c a t i o n o f m o n i t o r i n g w e l l s and t h e r e d u c t i o n o f r i s k s i n v o l v e d i n exploratory d r i l l i n g . Field

Problems

The t h r e e g e n e r a l o b j e c t i v e s u s u a l l y i n v o l v e d i n s u b s u r f a c e investigations are: • Location of buried m a t e r i a l s , • D e t e r m i n a t i o n o f t h e p r e s e n c e o f plumes and t h e d i r e c t i o n , r a t e o f movement, and d i s t r i b u t i o n o f contaminants; • C h a r a c t e r i z a t i o n of the geohydrologic conditions, n a t u r a l and manmade. L o c a t i o n o f b u r i e d m a t e r i a l s a t a hazardous waste s i t e i s u s u a l l y f o r the purpose of r e m e d i a l a c t i o n ; i . e . , e x c a v a t i n g t h e s e m a t e r i a l s and u l t i m a t e l y d i s p o s i n g o f them. The k e y unknowns a r e t y p e ( b u l k - d u m p e d o r p a c k a g e d i n drums o r o t h e r c o n t a i n e r s ) , q u a n t i t y (volume o f w a s t e ; number o f d r u m s ) , and l o c a t i o n , p a r t i c u l a r l y depth of b u r i a l . The c o n c e r n s a r e f o r s a f e e x c a v a t i o n w i t h o u t p u n c t u r i n g c o n t a i n e r s o r b r e a c h i n g any e x i s t i n g t r e n c h l i n e r s and t h u s a g g r a v a t i n g t h e c l e a n u p problems. D e t e r m i n a t i o n o f t h e p r e s e n c e o f c o n t a m i n a n t plumes and t h e i r f l o w d i r e c t i o n and movement r a t e i s commonly r e q u i r e d a t hazardous waste s i t e s . The f i r s t d e t e r m i n a t i o n i s w h e t h e r l e a k a g e from t h e hazardous waste s i t e i s o c c u r r i n g . I f the e x i s t e n c e o f a plume i s c o n f i r m e d , i t s d i r e c t i o n and e x t e n t s h o u l d be e s t a b l i s h e d and i d e n t i f i e d . A preliminary geophysical s u r v e y c a n a i d i n b e t t e r d e f i n i n g t h e c o n t a m i n a n t plume, l e a d i n g t o more e f f e c t i v e m o n i t o r i n g w i t h a s m a l l e r number o f m o n i t o r i n g wells.

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

8.

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Geophysical Methods for Investigations

C h a r a c t e r i z a t i o n o f the n a t u r a l s e t t i n g i s u s u a l l y a major p o r t i o n o f the f i e l d i n v e s t i g a t i o n . A t most s i t e s , p e r m e a b i l i t y o f t h e l o c a l s o i l and r o c k t y p e s , t h e d e p t h o f t h e w a t e r t a b l e , and t h e d i r e c t i o n o f g r o u n d w a t e r f l o w w i l l s t r o n g l y i n f l u e n c e movement o f c o n t a m i n a n t s f r o m t h e p o i n t o f d i s p o s a l . The anomalies which occur n a t u r a l l y w i t h i n the g e o h y d r o l o g i c s e c t i o n must be t a k e n i n t o c o n s i d e r a t i o n . S u r f a c e d r a i n a g e , sewers, and b u r i e d u t i l i t i e s c a n a f f e c t s u r f a c e and g r o u n d w a t e r f l o w a r o u n d a hazardous waste s i t e . Many o f t h e s e p r o b l e m s c a n o f t e n be a v o i d e d by t h e u s e o f an i n t e g r a t e d a p p r o a c h c o m b i n i n g c o n t e m p o r a r y g e o p h y s i c a l methods t o s u p p o r t t r a d i t i o n a l d r i l l i n g p r o c e d u r e s . Available Geophysical

Methodology

T h i s paper d i s c u s s e s s i x c u r r e n t l y a v a i l a b l e g e o p h y s i c a l s e n s i n g methods: g r o u n electromagnetic inductio m e t a l d e t e c t i o n , and m a g n e t o m e t r y . O t h e r g e o p h y s i c a l methods a r e a v a i l a b l e and a r e p r o v i n g t o be e f f e c t i v e ; s t i l l o t h e r s ( f o r example, complex r e s i s t i v i t y ) a r e emerging. However, t h i s d i s c u s s i o n has been l i m i t e d t o t h e s i x methods i n v o l v e d i n t h e l a r g e s t number o f a c t u a l s i t e i n v e s t i g a t i o n s t o d a t e . T a b l e I shows t h e p o s s i b l e r o l e s o f e a c h o f t h e s e methods i n h a z a r d o u s waste s i t e assessments. These methods s h o u l d be r e g a r d e d a s c o m p l e m e n t i n g one a n o t h e r . No one method i s u s e d f o r a l l a p p l i c a t i o n s , a n d some methods a r e u s e f u l i n more t h a n one application. I n g e n e r a l , m e t a l d e t e c t o r s and m a g n e t o m e t e r s a r e most u s e f u l i n l o c a t i n g b u r i e d w a s t e s ; g r o u n d p e n e t r a t i n g r a d a r i s the technique o f c h o i c e f o r d e f i n i n g the boundary o f b u r i e d t r e n c h e s ; e l e c t r o m a g n e t i c i n d u c t i o n (EM) a n d r e s i s t i v i t y a r e t h e most u s e f u l i n d e f i n i n g plumes o f c o n d u c t i v e c o n t a m i n a n t s i n g r o u n d w a t e r ; a n d r e s i s t i v i t y and s e i s m i c t e c h n i q u e s a r e most useful i n determining geologic stratigraphy. M e t a l D e t e c t o r s . M e t a l d e t e c t o r s r e s p o n d t o changes i n e l e c t r i c a l c o n d u c t i v i t y c a u s e d by t h e p r e s e n c e o f m e t a l l i c o b j e c t s , b o t h f e r r o u s and n o n - f e r r o u s . A t t h e same t i m e , m e t a l d e t e c t o r s a r e r e l a t i v e l y i n s e n s i t i v e t o changes i n s o i l m o i s t u r e or groundwater c o n d u c t i v i t y . The m a g n i t u d e o f r e s p o n s e f r o m a metal detector i s a function of several v a r i a b l e s . 1) Target t o sensor d i s t a n c e (response f a l l s o f as the s i x t h power o f t h e d i s t a n c e ) 2) Target s i z e 3) Target o r i e n t a t i o n 4) Target geometry 5) Type o f t a r g e t m e t a l 6) M e c h a n i c a l / e l e c t r i c a l i n t e g r i t y o f the t a r g e t 7) Search c o i l s i z e The o p e r a t i o n o f s i m p l e m e t a l d e t e c t o r s i s diagrammed s c h e m a t i c a l l y i n F i g u r e 1, w h i c h shows a n i n d u c t i o n b a l a n c e

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X - PRIMARY METHOD ( X ) - SECONDARY METHOD

LOCATION AND DEFINITION OF BURIED METALLIC OBJECTS (E.G., DRUMS, ORDINANCE)

LOCATION OF BOUNDARY DEFINITION OF BURIED TRENCHES

MAPPING OF GEOHYDROLOGIC FEATURES

MAPPING OF CONDUCTIVE LEACHATES AND CONTAMINANT PLUMES (E.G., LANDFILLS, ACIDS, BASES)

(X)

(X)

X

X

X

X

X

(X)

ELECTROMAGNETIC INDUCTION

(X)

X

X

RESISTIVITY

(X)

X

SEISMIC

X

(X)

METAL DETECTOR

POTENTIAL APPLICATIONS OF GEOPHYSICAL METHODS

GROUND PENETRATING RADAR

TABLE I .

X

(X)

MAGNETOMETER

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Figure 1. Simplified diagram of metal detector system.

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device. Such a d e v i c e c o n s i s t s o f a t r a n s m i t t e r l o o p c o i l and a r e c e i v e r l o o p c o i l g e o m e t r i c a l l y a r r a n g e d i n s u c h a way t h a t a n u l l or z e r o - i n d u c t i o n c o n d i t i o n i s a c h i e v e d i n the absence of n e a r b y m e t a l o b j e c t s . When t h e c o i l s a r e p r o p e r l y a d j u s t e d , t h e r e c e i v e r i s i n s e n s i t i v e to the e l e c t r o m a g n e t i c f i e l d of the transmitter. However, a s i g n a l w i l l be d e t e c t e d i f t h e e l e c t r o m a g n e t i c f i e l d a t t h e r e c e i v e r c o i l i s a l t e r e d by t h e s u p e r p o s i t i o n of a secondary e l e c t r o m a g n e t i c f i e l d r e s u l t i n g from c u r r e n t s induced i n a nearby m e t a l l i c o b j e c t or conductive mass by t h e t r a n s m i t t e r c o i l . D e v i a t i o n s from the balance c o n d i t i o n a r e d e t e c t e d as e l e c t r i c a l s i g n a l s i n t h e r e c e i v e r and a r e e l e c t r o n i c a l l y c o n v e r t e d t o a m e t e r d e f l e c t i o n as w e l l as t o an a u d i b l e t o n e . M e t a l d e t e c t o r s t e n d t o be i n s e n s i t i v e t o b u r i e d o b j e c t s o f s m a l l c r o s s - s e c t i o n , s u c h as m e t a l r o d s . (_1) F i g u r e 2 shows p r o f i l e s t a k e n w i t h a m e t a l d e t e c t o r a t a r u r a l s i t e where i t wa had been dumped i n t o a p a s s e s were made p e r p e n d i c u l a r t o t h e s u s p e c t e d t r e n c h as p a r t o f an e f f o r t t o d e t e r m i n e t h e l o c a t i o n and q u a n t i t y o f drums i n the t r e n c h . (2) M a g n e t o m e t e r s . M a g n e t o m e t e r s c a n be u s e d t o d e t e c t p e r t u r b a t i o n s i n t h e g e o m a g n e t i c f i e l d c r e a t e d by b u r i e d f e r r o m a g n e t i c o b j e c t s s u c h as s t e e l c o n t a i n e r s o r drums, t o o l s , or scrap metal. An i n d u c e d m a g n e t i z a t i o n i s p r o d u c e d i n any m a g n e t i c m a t e r i a l w i t h i n t h e e a r t h ' s m a g n e t i c f i e l d , and t h i s i n d u c e d f i e l d i s s u p e r i m p o s e d on t h e g e o m a g n e t i c f i e l d . If s t r o n g enough, t h i s i n d u c e d f i e l d p r o d u c e s a l o c a l i z e d anomaly i n the geomagnetic f i e l d . F i g u r e 3 i s a schematic of a simple magnetometer. The i n d u c e d m a g n e t i c f i e l d o f a b u r i e d o b j e c t depends on several variables: 1) T a r g e t mass; 2) Target to sensor d i s t a n c e ; 3) T a r g e t m a t e r i a l and i t s i n t e g r i t y ; 4) Target geometry ( p r i m a r i l y l e n g t h to diameter r a t i o ) 5) Target o r i e n t a t i o n ; 6) M a g n i t u d e and d i r e c t i o n o f permanent magnetism i n t h e target A v a r i e t y of magnetometers are c u r r e n t l y a v a i l a b l e f o r d i f f e r e n t types of s u r v e y s . B o t h t o t a l f i e l d and g r a d i o m e t e r s e a r c h magnetometers are used. P r o t o n p r e c e s s i o n and c e s i u m s y s t e m s a r e u s e d f o r measurements o f t h e t o t a l m a g n e t i c f i e l d . F l u x g a t e and c e s i u m g r a d i o r a e t e r s c a n be u s e d f o r s e a r c h work. A g r a d i o m e t e r i s a d i f f e r e n t i a l magnetometer w h i c h m e a s u r e s d i f f e r e n c e s i n t h e m a g n i t u d e and d i r e c t i o n o f t h e a m b i e n t f i e l d over a f i x e d d i s t a n c e ; t h i s f i x e d d i s t a n c e i s u s u a l l y small w i t h r e s p e c t to the d i s t a n c e to the o b j e c t c r e a t i n g the magnetic a n o m a l y . An a d v a n t a g e o f some g r a d i o m e t e r s y s t e m s i s t h e i r a b i l i t y to sense v e r t i c a l f i e l d g r a d i e n t s w h i l e r e m a i n i n g i n s e n s i t i v e t o h o r i z o n t a l g r a d i e n t components. T h i s f e a t u r e

In Risk Assessment at Hazardous Waste Sites; Long, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

Figure 2. Metal detector data over trench with buried drums.

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Simplified diagram of magnetometer system.

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a l l o w s gradioraeters t o sense the v e r t i c a l f i e l d o f s u b s u r f a c e t a r g e t s i n the presence o f h o r i z o n t a l i n t e r f e r e n c e t a r g e t s such as s t e e l f e n c e s . ( 3 ) F i g u r e 4 shows m u l t i p l e p a r a l l e l p r o f i l e s t a k e n w i t h a continuous r e a d i n g gradiometer over the d r u m - f i l l e d b u r i a l t r e n c h ( t h e same t r e n c h f r o m w h i c h F i g u r e 2 was t a k e n ) . These p r o f i l e s , w h i c h add c o n f i r m a t i o n o f t h e p r e s e n c e o f drums i n t h e t r e n c h , were t a k e n i n s i d e a h i g h s t e e l f e n c e e r e c t e d a r o u n d t h e suspected b u r i a l s i t e . ( 2 ) G r o u n d - P e n e t r a t i n g R a d a r . The g r o u n d - p e n e t r a t i n g radar (GPR) s y s t e m most f r e q u e n t l y u s e d i n h a z a r d o u s w a s t e s i t e i n v e s t i g a t i o n s i s an impulse system w h i c h r a d i a t e s s h o r t - d u r a t i o n e l e c t r o m a g n e t i c p u l s e s i n t o the ground from a n a n t e n n a n e a r t h e s u r f a c e . These p u l s e s a r e r e f l e c t e d f r o m various interfaces withi r e c e i v e r s e c t i o n o f th f o r p r o c e s s i n g a n d d i s p l a y . These r e f l e c t i o n s o c c u r a t different s o i l horizons, soil/rock interfaces, rock/air i n t e r f a c e s ( v o i d s ) , manmade o b j e c t s , o r a t a n y i n t e r f a c e w h i c h c r e a t e s a c o n t r a s t i n complex d i e l e c t r i c p r o p e r t i e s . F o r e x a m p l e , d i g g i n g a t r e n c h and f i l l i n g i t a g a i n c a n c r e a t e a d i f f e r e n c e between t h e d i e l e c t r i c p r o p e r t i e s o f t h e d i s t u r b e d e a r t h and t h o s e o f t h e u n d i s t u r b e d m a t e r i a l w h i c h c a n be s e n s e d by t h e GPR. F i g u r e 5 i s a schematic showing the v a r i o u s components o f a GPR s y s t e m . F o r p r e s e n t a t i o n o f d a t a , GPR s i g n a l s a r e p r o c e s s e d and d i s p l a y e d by a g r a p h i c r e c o r d e r . As t h e a n t e n n a i s moved a l o n g the s u r f a c e , the g r a p h i c d i s p l a y r e s u l t s i n a p i c t u r e - l i k e r e c o r d showing a c o n t i n u o u s p r o f i l e a l o n g a t r a v e r s e , v e r y s i m i l a r t o a g e o l o g i c c r o s s - s e c t i o n found a t a roadcut. U n f o r t u n a t e l y , the depth o f radar p e n e t r a t i o n i s very s i t e specific. D e p t h s o f 3 t o 10 m e t e r s a r e commonly a t t a i n e d t h r o u g h o u t t h e c o u n t r y ; 20 m e t e r p e n e t r a t i o n s have been a c h i e v e d u n d e r i d e a l c o n d i t i o n s a t some s i t e s . This depth i s reduced i f ground water i n c r e a s e s i n e l e c t r i c a l c o n d u c t i v i t y , o r i f t h e r e are s u f f i c i e n t l y high concentrations of f i n e grained m a t e r i a l s ( s i l t s or c l a y s ) present. For example, h i g h c o n c e n t r a t i o n s o f s a l t s , m o n t m o r i l l o n i t e c l a y o r l o s s e s are h i g h l y a t t e n u a t i v e of t h e r a d a r p u l s e and p e n e t r a t i o n may n o t e x c e e d one m e t e r . ( 4 ) F i g u r e 6 shows t h e c r o s s - s e c t i o n r e s u l t i n g f r o m a s i n g l e GPR t r a v e r s e a c r o s s t h e b a r r e l - f i l l e d t r e n c h f r o m w h i c h F i g u r e s 2 and 4 were t a k e n . The images p r o d u c e d by t h r e e 5 5 - g a l l o n b a r r e l s a r e i n d i c a t e d on t h e f i g u r e . Figure 7 i s a composite, c o m p a r i n g t h e t r a c e s o f F i g u r e s 2, 4, a n d 6. ( 5 ) Resistivity. The r e s i s t i v i t y method m e a s u r e s t h e e l e c t r i c a l r e s i s t i v i t y o f the g e o h y d r o l o g i c s e c t i o n , which i n c l u d e s s o i l , r o c k , and g r o u n d w a t e r . I n t e r p r e t a t i o n of these measurements p r o v i d e i n f o r m a t i o n on l a y e r i n g a n d d e p t h s o f s u b s u r f a c e h o r i z o n s a s w e l l a s l a t e r a l changes i n t h e

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Magnetometer data over trench with buried drums.

Graphic Recorder

Antenna Sampler Circuits

Controller 5-300 Meter Cable

Bow Tie

Tape Recorder

οο

Θ

Radar Waveform

α ο ο •

• Ground Surface-

ι Figure 5.

ι

ι

ι

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I

1 *°