Water Safety and Water Infrastructure Security [1 ed.] 9781118651872, 9781118651841

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WATER SAFETY AND WATER INFRASTRUCTURE SECURITY

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WATER SAFETY AND WATER INFRASTRUCTURE SECURITY

Edited by JOHN G. VOELLER Black & Veatch

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Copyright © 2014 by John Wiley & Sons, Inc. All rights reserved Published by John Wiley & Sons, Inc., Hoboken, New Jersey Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 750-4470, or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http://www.wiley.com/go/permission. Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages. For general information on our other products and services or for technical support, please contact our Customer Care Department within the United States at (800) 762-2974, outside the United States at (317) 572-3993 or fax (317) 572-4002. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic formats. For more information about Wiley products, visit our web site at www.wiley.com. ePDF: 9781118651872 ePub: 9781118652091 Printed in the United States of America 10 9 8 7 6 5 4 3 2 1

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CONTENTS

Preface 1. Potential Contamination Agents of Interest 2. Surveillance Methods and Technologies for Water and Wastewater Systems 3. Designing an Optimal Water Monitoring Systems 4. Emergency Response Planning for Drinking Water Systems 5. Treatability of Contaminants in Conventional Systems 6. Decontamination Methods for Drinking Water Treatment and Distribution Systems 7. Decontamination Methods for Wastewater and Stormwater Collection and Treatment Systems 8. Prevention of Contamination of Drinking Water in Buildings and Large Venues 9. Understanding the Implications of Critical Infrastructure Interdependencies for Water Index

vii 1 19 33 47 71 77 101 115 129 145

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PREFACE

Adapted from the Wiley Handbook of Science and Technology for Homeland Security. The topic of homeland security did not begin with the World Trade Center or the IRA or the dissidents of past empires, but began when the concept of a nation versus a tribe took root and allegiance to a people was a choice, not a mandate. The concept of terrorism is part of homeland security but there are other risks to homeland security; such as those that come from Mother Nature or negligence of infrastructure maintenance. Indeed, these factors have much higher probabilities of causing substantial damage and loss of life than any group of terrorists could ever conceive. Hence, the focus here is on situations that put humans at risk and can disrupt and damage infrastructure, businesses, and the environment, and on scientific and technological tools that can assist in detecting, preventing, mitigating, recovering, and repairing the effects of such situations. The number of science and technology (S&T) related topics that are involved in the physical, cyber and social areas of homeland security includes thousands of specialties in hundreds of disciplines so no single collection could hope to cover even a majority of these. Instead, our intention is to discuss selected topics in ways that will allow readers to acquire basic knowledge and awareness and encourage them to continue developing their understanding of the subjects. Naturally, in the context of homeland security and counterterrorism, some work has to be classified so as not to “communicate our punches” to our adversaries and this is especially true in a military setting. However, homeland security is concerned with solutions to domestic situations and these must be communicated to officials, law enforcement, and the public. Moreover, having experts speak in an open channel is important for informing researchers, academics, and students so that they can work together and increase our collective knowledge. There are many ways to address homeland security concerns and needs, and many different disciplines and specialties. An ongoing open conversation among experts which will allow them to connect with others and promote collaboration, shared learning and new relationships is needed. Certainly, creating a forum in which theories, approaches, vii

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solutions and implications could be discussed and compared would be beneficial. In addition, reliable sources from which experts and lay persons alike could learn about various facets of homeland security are needed. It is equally important that policy and decision makers get the full picture of how much has been done and how much still needs to be done in related areas. Even in places that have dealt with terrorism for over a century, there are no strong, cost-effective solutions to some of the most pressing problems. For example, from a distance, we have very limited ability to spot a bomb in a car moving toward a building to allow decision making on whether to destroy or divert the car before it can damage the target. Even simpler, the ability to spot a personnel-borne improvised explosive device (IED) in a crowd coming into a busy venue is still beyond our collective capability. Therefore, the bounding of what we know and don’t know needs to be documented. Finding additional uses for technologies developed originally to solve a homeland security problem is one of the most important aspects of the economics involved. An inescapable issue in many areas of homeland security S&T, is that even a successful solution when applied to only a small market will likely fail because of insufficient returns. For example, building a few hundred detectors for specific pathogens is likely to fail because of limited demand, or it may never even receive funding in the first place. The solution to this issue is finding multiple uses for such devices. In such a case, a chemical detector for contraband or dangerous materials could be used also to detect specific air pollutants in a building; thus, help allergy sufferers. In this way capabilities developed for homeland security may benefit other, more frequently needed uses, thereby making the invention more viable. The editors of this work have done a superb job of assembling authors and topics and ensuring good balance between fundamentals and details in the chapters. The authors were asked to contribute material that was instructional, discusses a specific threat and a solution, or provides a case study on different ways a problem could be addressed and what was found to be effective. We wanted new material where possible. The authors have produced valuable content and worked hard to enhance quality and clarity of the chapters. And finally, the Wiley staff has taken on the management of contributors with patience and energy beyond measure. Senior Editor John G. Voeller

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1 POTENTIAL CONTAMINATION AGENTS OF INTEREST Robert M. Clark Cincinnati, Ohio

1.1

INTRODUCTION

There are nearly 60,000 community water supplies in the United States serving over 226 million people. Over 63% of these systems supply water to less then 2.4% of the population and 5.4% supply water to 78.5% of the population. Most of these systems provide water to less then 500 people. In addition, there are 140,000 noncommunity systems that serve schools, recreational areas, trailer parks, etc. [1]. Some of the common elements associated with water supply systems in the United States are as follows: •

Water source, which may be a surface impoundment such as a lake, reservoir, river, or ground water from an aquifer; • Conventional treatment facilities, including filtration, which removes particulates and potentially pathogenic organisms, followed by disinfection, primarily for surface supplies; • Transmissions systems, which include tunnels, reservoirs, and/or pumping facilities, and storage facilities; • Distribution systems, carrying finished water through a system of water mains and subsidiary pipes to consumers.

1.2

WATER SYSTEM VULNERABILITY

Water systems are spatially diverse and therefore, have an inherent potential to be vulnerable to a variety of physical, chemical and biological threats that might compromise a systems’ ability to reliably deliver safe water. Community water supplies are designed to deliver water under pressure and generally supply most of the water for firefighting purposes. Therefore a loss of water or a substantial loss of pressure could disable firefighting capability, interrupt service, and disrupt public confidence. This loss might result from sabotaging pumps that maintain flow and pressure, or disabling electric power sources Water Safety and Water Infrastructure Security, Edited by John G. Voeller © 2014 John Wiley & Sons, Inc. Published 2014 by John Wiley & Sons, Inc.

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that might lead to long term disruption. Many of the major pumps and power sources in water systems have custom-designed equipment and could take months or longer to repair and/or replace [2]. Major areas of vulnerability include the following: • • • • • • •

raw water source (surface or groundwater); raw water channels and pipelines; raw water reservoirs; treatment facilities; connections to the distribution systems; pump stations and valves; finished water tanks and reservoirs.

Each of these system elements present unique challenges to a water utility in safeguarding water supply [3].

1.2.1

Physical Disruption

The ability of a water supply to provide water to its customers can be compromised by destroying or disrupting key physical elements of the water system. These elements include raw water facilities (dams, reservoirs, pipes, and channels), treatment facilities, and distribution system elements (transmission lines and pump stations). Physical disruption may result in significant economic cost, inconvenience, and loss of confidence by customers, but has a limited direct threat to human health. Exceptions to this generalization include (i) destruction of a dam that causes loss of life and property in the accompanying flood wave and (ii) an explosive release of chlorine gas at a treatment plant. Water utilities should examine their physical assets, determine areas of vulnerability, and increase security accordingly. An example of such an action might be to switch from chlorine gas to liquid hypochlorite, especially in less secure locations which decreases the risk of exposure to poisonous chlorine gas. Redundant system components would provide backup capability in case of accidental or purposeful damage to facilities.

1.2.2

Contamination

Contamination is generally viewed as the most serious potential terrorist threat to water systems. Chemical or biological agents could spread throughout a distribution system and result in sickness or death among the consumers, and for some agents the presence of the contaminant might not be known until emergency rooms report an increase in patients with a particular set of symptoms. Even without serious health impacts, just the knowledge that a group had breached a water system could seriously undermine consumer confidence in public water supplies [4]. Accidental contamination of water systems has resulted in many fatalities. Examples of such outbreaks include cholera contamination in Peru [5], Cryptosporidium contamination in Milwaukee, Wisconsin (US) [6], and Salmonella contamination in Gideon Missouri (US). In Gideon the likely culprit was identified as pigeons infected with Salmonella that had entered a tank’s corroded vents and hatches [7].

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MICROBIAL THREATS

1.3

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MICROBIAL THREATS

Waterborne pathogens have been recognized as a threat to human public health throughout history but the development of drinking water treatment techniques have controlled this threat since the beginning of the twentieth century. Although modern drinking water treatment has virtually eradicated waterborne disease from developed countries, drinking water treatment systems have been identified as a potential security vulnerability. Water-related microbial pathogens can be categorized as water-based or waterborne pathogens. Water-based pathogens spend part of their life cycle in water to reach and infect a potential host. An excellent example of a water-based pathogen is malaria for which mosquitoes are a vector. Since water-based pathogens are not transmitted totally through water they are not potential agents of bioterrorism. Waterborne pathogens, however, are those transmitted through ingestion of contaminated water primarily through the fecal-oral route. In this case water acts as a passive carrier of infectious agents. Some waterborne pathogens that can cause problems in drinking water include Campylobacter jejuni , pathogenic Escherichia coli , Yersinia enterocolitica, enteric viruses such as rotavirus, calicivirus, astrovirus, and parasites such as Giardia lamblia, Cryptosporidium parvum and Microsporidia sp. Table 1.1 provides useful summary information related to these organisms. Some species of environmental bacteria have demonstrated the ability to survive in drinking water biofilms and have been identified as opportunistic pathogens including Legionella spp., Aeromonas spp., Mycobacterium spp., and Pseudomonas aeruginosa [8–10]. Bacterial pathogens can cause gastroenteritis, including cramps, diarrhea, nausea, vomiting, chills, and mild fever. Bacterial pathogens are generally sensitive to disinfectants such as chlorine and include the following [2, 3, 8, 14]: • • • • • • •

Salmonella; Shigella; Escherichia coli O157:H7; Yersinia; Vibrio; Campylobacter; Legionella.

Viral pathogens can pose a 10- to 10,000-fold higher infection risk then bacteria. Important waterborne viral pathogens include the following: • • • • • •

Adenovirus; Astroviruses; Hepatitis A; Hepatitis E; Norovirus; Rotaviruses.

Parasitic pathogens are a significant threat to drinking water supplies. Nearly 20,000 protozoan parasites have been identified of which 20 genera are known to cause diseases in humans some of which include the following:

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TABLE 1.1

Pathogens of Public Health Significancea,b,c,d,e

Pathogen Salmonella bongori and Salmonella enterica Salmonella paratyphi A, B, and C Salmonella typhi Shigella dysenteriae, S. flexneri, S. boydii, and S. sonnei Vibrio cholerae Vibrio parahaemolyticus Yersinia enterocolitica Clostridium perfringens Bacillus cereus Escherichia coli enteropathogenic Coxsackeivirus Hepatitis A virus Polio virus Cryptosporidium sp. Entamoeba histolytica Naegleria fowleri

Disease Salmonellosis Paratyphoid fever Typhoid fever Shigellosis (bacillary dysentery) Cholera Gastroenteritis Yersiniosis — — Endemic diarrhea Gastroenteritis Hepatitis Poliomyelitis Cryptosporidiosis Amoebiasis Naegleriasis and Acanthamebiasis

Incubation Period 12–36 h 8–14 d 1–3 wk 1–7 d 2–3 d 8–48 h 3–7 d 10–12 h 6–24 h 9–12 h 3–5 d 28–30 d 7–14 d 7d 2–4 wk 3–7 d

a Abbaszadegan

and Alum [8]. and Renner [11, 12]. c Clark and Deininger [2, 3]. d American Public Health Association [13]. e http://www.bt.cdc.gov/agent/agentlist.asp. b Burrows

• • • • •

Acanthamoeba, Cryptosporidium parvum, Entamoeba histolytica, Microsporidia, and Naegleria.

In general, the most effective mechanism for controlling these pathogens is disinfection, especially with chlorine. Table 1.2 summarizes the capacity of chlorine for inactivating water-related pathogens based on CT values. In calculating CT , C is the concentration of disinfectant (chlorine) in mg/l and T time in minutes. Column 4 contains the CT value and the target reduction for a given CT is given in Table 1.5 [8, 15, 16]. However other disinfectants may also be effective. Table 1.3 summarizes CT times for a representative set of microorganisms based on the use of chlorine, chloramines, ozone and chlorine dioxide [17]. As can be seen, ozone is the most effective disinfectant but it does not maintain a residual, and is therefore of only limited use in protecting a distribution system. 1.3.1

Biological Agents

In addition to general pathogens of concern in water supplies some pathogens can be categorized as biological warfare agents. Table 1.4 contains a basic listing of potential

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TABLE 1.2 Inactivation of Microbes using Chlorinea,b Temperature (◦ C)

pH

C×T (mg/l × min)

Percentage Reduction

Campylobacter jejuni E. coli Legionella pneumophila Mycobacterium chelonei Mycobacterium fortuitum Mycobacterium intracellulare Salmonella typhi Shigella dysentriae Vibrio cholerae S. strain Vibrio cholerae R. strain Yersinia enterocolitica Adenovirus Hepatitis A Norovirus

25 25 21 25 — — 20 20–29 20 20 20 25 25 25

8.0 7.0 7.6–8.0 7.0 7.0 7.0 — 7.0 7.0 7.0 7.0 8.8–9.0 6 7.4

0.5 3.0 17.5 42 30 9 3 0.5 1 60 30 0.132 0.42 22.5

Rotavirus Crytposporidium parvum Entamoeba histolytica Giardia lamblia Naegleria fowleri

25 25 22–25 25 25

7.4 7.0 7.0 6.0–8.0 7.3–7.4

22.5 7200 50 15 45

99.99 99.99 99 99.95 99.4 70 99 99.6–100 100 >5 logs 92 99.8 99.99 Not completely inactivated 100 90 100 100 99.99

Bacteria

a Abbaszadegan

and Alum [8].

b http://www.bt.cdc.gov/agent/agentlist.asp.

warfare agents and Table 1.5 contains potential warfare biotoxins. The biological agents listed in Tables 1.4 and 1.5 are not only deadly in their own right but also have the potential to be weaponized. Table 1.5 provides a general overview of the organisms that might be used in biological warfare. Some of the organisms that have potential use in bioterrorism are discussed below [2, 3, 11, 12]. Anthrax. Anthrax, a highly infectious disease of hooved animals, is easily transmitted to humans. The three recognized forms of disease in humans are cutaneous, pulmonary, and gastrointestinal. It is caused by a spore-forming bacterium, Bacillus anthraces, which has been weaponized for aerosol application and was used by the Japanese Army during World War II to contaminate food and water supplies of Chinese cities [12]. Abdominal pain, fever, vomiting, bloody diarrhea and shock are the principal manifestations of this form of the disease, which has an incubation period of 2–7 days. Anthrax spores are easily removed by any water treatment filter system with pore size 0.1–1.0 mg/l, malathion at >1.0–10.0 mg/l, phenol at >10.0–100.0 mg/l, and acetone at >100 mg/l. 2.4

MONITORING FOR RADIATION TO DETECT RADIONUCLIDES

Radiation monitoring equipment is designed to measure either the total amount of radiation emitted from a source (gross radiation) or the specific types and energy levels of radiation emitted from a source. Responders trying to determine whether there is an elevated level of radiation in the water from accidental releases or intentional introductions do not necessarily require that the specific radionuclides causing the contamination be immediately identified. They would rather most likely be interested in utilizing some type of continuous, on-line screening equipment to measure gross radiation. The common types of gross radiation are α, β, and γ . On-line instruments for monitoring α, β, and γ radiation in water have been developed. However, there are a limited number of models available, and they can be expensive. Technical Associates16 offers the SSS-33-5FT for approximately $58,000. This is a flow-through scintillation detection system for α-, β-, and γ -radiation monitoring. The detector can be preset to measure one type of radiation, or all three combined, and can be equipped with a system that sends an alert if unusual counts are detected. Canberra17 13

Bio-Sensors Inc., Blacksburg, VA. Intelligent Aquatic Biomonitoring System (iABS), Intelligent Automation Corp., Poway, CA. 15 Seiko Corp., Japan. 16 Technical Associates, Los Angeles, CA. 17 Canberra, Meriden, CT. 14

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sells the OLM-100 on-line liquid monitoring system, which is attached to the exterior of a pipe and continuously measures the radiation in a liquid stream. The cost of this device is between $35,000 and $70,000 [4].

2.5

SCREENING FOR SPECIFIC CHEMICAL CONTAMINANTS

Unlike the general organic chemical load monitors (TOC and UV–vis spectrometry), gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS) can detect, identify, and measure the concentration of a wide variety of specific organic compounds. In fact, of all of the on-line physical/chemical monitors described above, GC and GC–MS are the only analytical techniques, currently being deployed in a continuous on-line mode, which can actually identify a specific chemical contaminant. Both these techniques can detect and identify a large number of volatile organic compounds in the low parts per billion (ppb) to parts per million (ppm) range, and can operate automatically and unattended. In the case of GC, the components of a complex mixture are separated, their retention times are compared to known standards, and then the concentrations are quantified. In GC–MS, the organic components are separated by GC, and a more definitive identification of contaminants is provided by mass spectrometry using mass to charge ratio of chemical compound fragments and comparing the mass spectrum with internal libraries that contain thousands of chemical fingerprints of known organic compounds. Some of the on-line devices collect and concentrate volatile organic compounds (VOCs) from water using standard purge and trap technology. In the continuous on-line mode, sample collection is automated and analysis occurs at regular programmable intervals throughout a 24-h period. INFICON18 manufactures both GC and GC–MS instruments that utilize purge and trap, and can be operated as on-line monitors for either natural waters or finished drinking waters. A highly specialized mass spectrometer is being utilized to screen water samples, in an on-line mode, at the Phoenix Arizona Water Services Department [5]. This photoionization and quadrupole ion trap, time-of-flight mass spectrometer provides high-speed screening and molecular identification for weaponized chemicals and other hazardous compounds. The commercially available mass spectrometer is used in an automated mode as an early warning system screening device. The advantage of this particular mass spectrometry approach is that it can be operated on-line and, unlike most mass spectrometers, can analyze mixtures of compounds without preliminary separation by GC. With its integrated autosampler, the instrument provides a high throughput monitor capable of analyzing samples every 45 s.

2.6

SCREENING FOR SPECIFIC PATHOGENS

While a number of devices are currently employed for real-time monitoring of the general chemical characteristics of water (e.g. chlorine concentration and TOC), and for screening for specific chemical contaminants (e.g. on-line GC–MS), the ability to continually screen drinking water for the presence of microorganisms is still quite limited. 18 INFICON

Corp., East Syracuse, NY.

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A microbial sensor must include a recognition device (bioreceptor), which can react with a target microbe. One approach is to utilize immunoassay-based sensors that recognize specific proteins on the surface of a microbe. Another approach is to employ a bioreceptor that recognizes nucleic acid, either DNA (deoxyribonucleic acid) or RNA (ribonucleic acid), uniquely characteristic of a specific microorganism. When the target protein or nucleic acid is present in the sample, a biological reaction takes place between it and the bioreceptor, creating a physical or chemical change that is converted into an electrical signal proportional to the target microorganism’s concentration in the solution. The signal is then amplified, processed, and displayed as a measurable piece of data [6]. In the case of immunoassay-based sensors, antibodies that have an affinity for specific antigens associated with a particular species are utilized. Antibody-based biosensors incorporate antibodies onto a sensor surface and utilize the hybridization between antigen and antibody as the recognition factor [7]. Nucleic acid-based bioreceptors contain on their surface an oligonucleotide that is complimentary to the nucleic acid sequence of the target organism. Recognition consists of hybridization between the bioreceptor’s complimentary oligonucleotide and the target microbe’s single stranded DNA or RNA. The hybridization reaction generates either an amperometric, optical, thermal, or mass differential signal that is amplified for quantification. The major technical problem associated with nucleic acid biosensing, unlike immunoassay biosensing, is that the DNA or RNA must first be extracted from the target cell. The extraction process requires reagents and incubation steps. Furthermore, following extraction, the double stranded DNA must be denatured into single stranded DNA through a heating process. The challenge lies in fully automating the pretreatment extraction and denaturation steps. An advantage of both immunoassay- and nucleic acid-based sensors is that they can be highly specific and, therefore, able to identify a specific target microbe with certainty. However, since there is such a variety of microbes that could accidentally or intentionally contaminate a water system, these approaches would require the deployment of a complicated array of bioreceptors to provide broad spectrum coverage. An additional disadvantage of both nucleic acid- and antibody-based biosensors is the lifespan and fragility of the recognition system. Nucleic acids and antibodies are biological macromolecules that can be damaged by conditions typical of water and wastewater systems. Another biosensor approach for on-line biomonitoring of water systems utilizes amperometric detection of the β-galactosidase enzyme for detection of E. coli [8]. β-Galactosidase is an enzyme involved in lactose fermentation in E. coli . In this biosensor system, reagents are added to induce production of β-galactosidase in E. coli present in the sample, which, in turn, hydrolyzes the reagent phenyl β-d-galactopyranoside to produce phenol, which is detected by an amperometric sensor. Using this system, sensitivity of detection has been observed at a level of 10 CFU/ml of E. coli after a 5-h incubation period. Although the sensitivity of this system is generally greater than that of nucleic acid or immunoassay systems, the obvious disadvantages of its application as a real-time microbial sensor are the requirements for reagents, the 5-h incubation time, and the biosensors’s specificity for a single bacterial species. Still another biosensor approach for continuous monitoring is based on optical recognition of microbes [9]. Multiangle light scattering (MALS) is a reagent-less optical approach. MALS technology involves continual irradiation of a flowing column of water with a laser beam. Particles in the column of water scatter the laser beam producing a pattern that is detected by a number of detectors on the opposite side of the water

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column. Since a variety of angles are monitored simultaneously, a three-dimensional pattern is generated that represents the structure and size of the particle in the laser’s path. The goal of MALS is to differentiate between waterborne microorganisms and inorganic particles based on the pattern of scattered light. An additional objective is to identify microbes by comparing the pattern of scattered light with a library of unique “bio-optical signatures” that have been developed by analyzing known microorganisms. The light pattern resembles a fingerprint since it is unique to the internal and surface features of the particles, including size, shape, morphology, and material composition. The current limitations of MALS for on-line monitoring include interferences from organic and inorganic particulate matter in the water sample stream, and difficulty achieving low detection limits. However, developmental efforts are being taken to address these issues. 2.7 PATHOGEN DETECTION SYSTEMS CURRENTLY UNDER DEVELOPMENT Several continuous monitoring systems for pathogens have been designed, based on the biosensor approaches described above, and are deployed in several drinking water utilities in the United States. Two of these are described below. JMAR Technologies19 manufactures the Biosentry System which is a commercial application of the MALS technology optical approach [10]. This technique has been commercially applied in the beverage industry and is now being adapted for use in drinking water utilities [11]. Biosentry is a laser-based system that continuously monitors water for microbes of interest, including pathogens, and attempts to classify them. The system can be used simply as a monitoring device recording microbe counts against time. Alternatively, the system can provide a real-time warning when a predetermined threshold for a particular pathogenic microbe is reached. The device can operate remotely and transmit data into a SCADA network via an encrypted internet connection. The system can send an alert via a number of means, including e-mail and encrypted internet, or directly into a linked information system. Information is refreshed at 1-min intervals and microbial counts are displayed for the species being monitored as well as for unclassified microorganisms. The system typically monitors a water stream of about 35 ml/min. Sensitivity, and the ability to discriminate between various particles and microbes, is optimal with water containing fewer background particles (i.e.