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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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Suggested Citation:"2. Assessment." National Research Council. 2003. Review of EPA Homeland Security Efforts: Safe Buildings Program Research Implementation Plan. Washington, DC: The National Academies Press. doi: 10.17226/10864.
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2 Assessment NRC ASSESSMENT CONTEXT AND CRITERIA The committee recognizes that the building protec- tion and decontamination tasks the Environmental Protection Agency (EPA) has been given are both exceedingly important and extremely challenging. Analyses of the decision processes required to effec- tively handle a chemical or biological attack on a civilian or public sector facility demonstrate that a wide range of time-critical information and technical capa- bilities are required to identify, respond to, character- ize, and decontaminate or remediate the resulting damage (Raber et al. 2002~. Evaluations of the responses to recent anthrax contamination of congres- sional and Post Office facilities clearly demonstrate the severe management and technical difficulties posed by even a modest biological attack (EPA, 2002; GAO, 2003b). While some straightforward measures have been identified to protect buildings from chemical or biological attacks (CDCINIOSH, 2002), more compre- hensive attack warning, evaluation, and containment strategies will require extensive advances in building systems and their components. The EPA Safe Buildings Program was conceived as a comprehensive response to these challenges. The lEPA, 2003, Research Implementation Plan Safe Buildings Program (Draft), presented to the committee on May 13, 2003, by N. Adams, Environmental Protection Agency, Research Triangle Park, NC. program is motivated by a threat analysis performed by the agency with input from a range of relevant federal sources.2 However, the current program is constrained by the time frame (three years total, approximately 30 months remaining at the start of this review pro- cess). Given the time currently available to the program, the committee has attempted to identify criti- cal safe building research and development challenges that might be substantially completed within the time and cost constraints as well as to note those that will clearly require longer time frames or more substantial budgets or both to ensure significant progress. It is also apparent to the committee that execution of any safe buildings program will require an extremely wide range of chemical, biological, engineering, and social science expertise. EPA' s traditional role of pro- tecting human health and ecosystem viability from insult by industrial and commercial products and by- products has resulted in many staff and contractor capabilities that are very pertinent to the safe buildings challenge. However, the agency and its contractors may not have all the skills required to specify, develop, evaluate, and demonstrate desirable safe buildings 2EPA, 2003, Analysis of Potential Scenarios for Terrorist Attacks on Buildings with Biological or Chemical Agents (Draft), Lemieux, P., Adams, N., and Sparks, L., presented to the committee on July 10, 2003, by N. Adams, Environmental Protection Agency, Research Triangle Park, NC. s

6 technology components and systems. The committee has attempted to identify Safe Buildings Program tasks that require technical expertise in areas where the agency has strong and in some cases even unique capa- bilities; as well as to flag those tasks for which the agency will need to develop new skills or acquire new collaborators to succeed. Given the time scale for the current Safe Buildings Program, the committee recommends that priority be given to those tasks that can reasonably be completed within the program time frame and that draw most heavily on the technical expertise of EPA's laborato- ries and current contractors. The committee also recommends that longer-range tasks and those that require the development of expanded capabilities be deferred in the short term or undertaken only in close collaboration with agencies and organizations with the required capabilities. The committee notes that the threat scenario used to define the Safe Buildings Programs should be used to identify priority needs and to set program goals. The Safe Buildings Program will likely be most successful when specific, realistic program goals are set early in the program and when success or failure is consistently and systematically measured against those goals as the program evolves. In the assessments of each Safe Buildings Program element presented below the com- mittee identifies goals and measures of success. EPA also has a list for measures of success within the three-year time framed: · identify the most important threats (key drivers . of the program); develop and define appropriate and effective methods for detecting, containing, and decon- taminating events relating to these top threats; · produce methods and guidance for understanding and predicting human health risks; · lead the development of clean-up standards; and 3EPA, 2003, Analysis of Potential Scenarios for Terrorist Attacks on Buildings with Biological or Chemical Agents (Draft), Lemieux, P., Adams, N., and Sparks, L., presented to the committee on July 10, 2003, by N. Adams, Environmental Protection Agency, Research Triangle Park, NC. 4EPA, 2003, Research Planning in the Safe Buildings Program Report to the National Academies, presented to the committee on June 30, 2003, by N. Adams, Environmental Protection Agency, Research Triangle Park, NC, p. 29. REVIEW OF EPA HOMELAND SECURITY EFFORTS · distribute methods/guidance to building owners, responders, and appropriate public officials (An additional measure of success will be successful use of these technologies and the guidance by our customers.) The committee' s assessment evaluates the program in the context of these success factors as well as others identified by the committee in its discussions. DETECTION Different Approaches to Chemical and Biological Detection and Characterization Systems In 1999 the National Research Council (1999a) dis- cussed numerous biological and chemical detection systems, many of which have since been improved. The advantages and disadvantages of these systems should be incorportated into EPA's strategy for characteriza- tion, decontamination, and recovery. The technologies most applicable to monitoring and notification for any agent must be sensitive enough to detect agent concen- trations at or below health risk levels, specific enough to provide acceptable false-alarm rates, and prompt enough for notification consistent with effective medi- cal response. This generally equates to a critical response time of minutes for chemical agents and toxic industrial chemicals and days for most biological agents. For attacks using chemical warfare agents, symptoms are typically prompt, with coughing, chok- ing, distress, and sometimes death occurring as soon as seconds after exposure. Detectors must respond in nearly real time to minimize exposures and guide medi- cal intervention. Following a chemical attack it is likely that well-established hazardous material operations would be conducted during the notification phase. Chemical sensors that respond quickly are already available commercially from several sources, and analytic instruments incorporating preconcentration methods are already available to detect and identify chemical warfare agents at or below known health risk limits. Many of these methods have been developed to support either the military or the current international chemical weapons treaty verification program. After the Aum Shinrikyo attack in Tokyo, strategies have been investigated for detecting and responding to chemical warfare agents in semi-enclosed structures, such as subways and airports. In the United States,

ASSESSMENT much of this work has been conducted through agencies that are now part of the Department of Homeland Security. The NRC Committee on Safe Buildings Pro- gram recommends that EPA continue to utilize these ongoing studies to aid implementation of the Safe Buildings Program. For biological attacks detection can be based on environmental monitoring, epidemiological monitor- ing, or an unusual diagnosis, as was the case with the inhalation anthrax incidents. Actual detection of an event is much more difficult and the time delay is significant when compared with chemical incidents. Several projects both within EPA and other agencies are underway to enhance early detection and notifica- tion, and some environmental monitoring systems have already been deployed in major U.S. metropolitan areas (Cole, 2003~. Because many biological threat agents are zoonotic (outbreaks naturally occurring in animals), biodetection systems must discriminate between unnatural events and naturally occurring backgrounds. For all detection systems it is important to recog- nize that detectors alone do not directly measure threats to people. For instance, chemical detectors often can- not detect the lowest dose known to be a health risk without a Reconcentration step, and biological detec- tors usually cannot determine viability of an agent or other important health-associated attributes, such as antibiotic resistance. Historically the military has set standards for chemical and biological detection for battlefield scenarios. The civilian community needs standards and uniform test protocols to ensure that sys- tems perform predictably and that decision makers will be confident they will understand the information pro- vided. Civilian applications demand high standards for performance, including low false alarm rates. An important role for the EPA Safe Buildings Program would be the establishing of these standards and uni- form test protocols. Detection to Assess Containment and for Post- Decontamination Evaluation The stated focus of the Safe Buildings Program is building decontamination,5 and it is in decontamina- sEPA, 2003, Research Planning in the Safe Buildings Program Report to the National Academies, presented to the committee on June 30, 2003, by N. Adams, Environmental Protection Agency, Research Triangle Park, NC, p. 5. 7 tion rather than detection that the EPA has leading expertise. Thus, the detection program should focus exclusively on decontamination, as indicated by the information provided to the panel from EPA. All tech- nical parts of the program should be subordinate to de- contamination and each part should technically sup- port decontamination to achieve results within the prescribed time period of the program (approximately 30 additional months). The specific components of detections that the committee feels should be highlighted are · the creation and publication of decontamination standards; · specific specifications for detectors to support de- contamination; and field-testing of detectors and decontamination strategies against the specifications provided above. . The committee concludes that EPA should lead the development of cleanup standards and sponsor and su- pervise realistic field tests to validate the decontamina- tion protocols, including detection equipment for de- termining that necessary re-entry levels have been met. Beyond that, for the area of detection the mea- sures of success given by EPA all fall into less impor- tant categories and should be removed from the EPA's funding portfolio since they do not support the program's primary objective. Test-Beds and Protocols for Technological Systems EPA's expertise in building safety has been on facility rehabilitation. As such, the concept of restora- tion of service is a key tenet of the EPA's core strength. To continue to effectively accomplish the mission of building safety and restoration EPA needs to focus its research in the Safe Buildings Program on decontami- nation and disposal. The components of the Safe Build- ings program that are related to detection need to be fully directed toward support of the primary mission of decontamination and disposal. The components of the program that deal with detect-to-warn, in the 6EPA, 2003, Research Planning in the Safe Buildings Program Report to the National Academies, presented to the committee on June 30, 2003, by N. Adams, Environmental Protection Agency, Research Triangle Park, NC, p. 23.

8 committee's view, have little possibility for benefit to either EPA or Homeland Security under the scope and duration of the program, as the program duration is too short to successfully complete this effort. Due to the limited time available, EPA should focus on decon- tamination. Any research on detect-to-warn, other than by collaborating with other agencies, is outside the cur- rent scope of EPA, and it would be unrealistic for EPA to expect any results in the remaining time. A second overarching issue is the need to accom- plish results within the program time frame. The com- mittee detected a lack of focus during the first six months of research that has resulted in a dilution of the overall program. The committee feels that significant restructuring of detector research is needed, because detection has a number of components that are impor- tant to decontamination efforts. The committee feels that in the remaining 30 months in the program, the detection area should be focused to support the more tractable area of decontamination. Specifically, EPA needs to focus a significant amount of its detection capabilities on answering the question "How clean is clean?" The establishment of standards for decontamination is within the purview of EPA, and it should take the lead in these efforts and be assisted by NIST and the Science and Technology Directorate of the Department of Homeland Security. In summary, detector development should play a subordinate role to other components of EPA's Sci- ence and Technology program for homeland security. The area of detector development is not one in which EPA should play a leading role, nor is it one in which EPA should play a development role. EPA should be involved in setting standards for decontamination, as well as in testing commercial equipment to achieve the level of decontamination standards that detection will certify. This means that EPA must collaborate with other agencies to establish relevant standards and test- ing protocols. As noted above, the committee recommends that EPA not pursue detect-to-warn systems further (due to the complexity of the issues and because this is outside EPA's primary expertise). If EPA chooses to pursue further research in this area, it is essential that the speci- fications of the warning system be tied to meaningful endpoints. For example, acute toxicology (or infectiv- ity) thresholds for agents of concern should be consid- ered, and the detection limit should be low enough (considering sampling time) that the agent can be detected before causing significant toxicity. If an agent REVIEW OF EPA HOMELAND SECURITY EFFORTS can be detected before causing toxicity, then indi- viduals that would have been infected otherwise have a chance to get out of the building and the decontamina- tion procedure can begin at an earlier time. Specifications for detection for re-entry should take into account the toxicology of the agents of interest. The detector should be able to detect levels exceeding chronic health guidelines (e.g., exceeding the reference concentration) following measurement for a specified period of time. Sampling time for reliable measure- ments should also be considered, although such con- siderations are less limiting, because measurement for re-entry can include sampling times on the order of days. Role of the EPA Environmental Technology Verification Program Establishment of required chemical and biological agent detectors and detection systems for a range of potential applications is an important challenge for EPA's Safe Buildings Program. More robust, sensi- tive, specific, and faster responding sensors will be necessary for successful containment, decontamina- tion, and potentially even disposal activities. However, specification of sensor capabilities will not be suffi- cient; detection instruments and integrated sensor systems must be proven under realistically simulated conditions using both surrogate and, in many cases, actual chemical and biological substances. Substantial technical effort and resources will be required to test threat agent detectors and detection sys- tems. Technical skills will be needed in designing realistic tests; - creating valid sampling and detection protocols; - arranging accurate instrument calibration samples and variable-strength, statistically robust, con- taminant challenges in appropriate matrixes; and · accurately scoring the performance of a range of instruments based on disparate physical, chemi- cal, or biological principles. The difficulty increases when the use of military grade chemical or biological agents requires a level of isolation and containment available only in certified surety facilities. To be credible, verification testing must be done in independent trials designed, operated, and scored by third parties with no direct stake in their outcome.

ASSESSMENT Through its Environmental Technology Verifica- tion (ETV) program EPA has experience in certifica- tion testing of pollutant detectors and detection systems and would be appropriate to extend this program to cover threat agent detectors and detection systems. For current ETV projects an EPA contractor designs the test program and invites instrument developers and vendors to bring prototypes or early production instru- ments to the test for certification. Scientists and engi- neers from EPA and other agencies may contribute to test specifications and design and also attend the verifi- cation tests. CONTAINMENT Importance of Understanding Buildings Buildings represent an important threat and exPo- sure category for the deliberate or accidental release of chemical or biological agents. Most of us spend between 75 and 90 percent of our time in buildings at work, at home, in schools, or in commercial establish- ments. Buildings themselves and their occupants may be direct targets of a chemical or biological attack or an indirect target (downwind of a release targeted at another facility); in either event buildings can offer potential safe havens. Buildings and building opera- tions can also help confine and spread harmful con- taminants. The focus of EPA's containment research is on the development and testing of methods to prevent the spread of contaminants thereby protecting building occupants, first responders, and decontamination crews. The overall objective is to reduce or eliminate the impact of a chemical or biological attack on build- ing occupants as well as to provide techniques and guidance to determine the efficacy of chemical and bio- logical protection measures for new and existing build- ings. The research seeks to understand the building so as to aid in safe, efficient, and cost-effective restoration. The spread of contaminants in a building is gener- ally by air circulation in large open spaces, airflow between connecting spaces, and airflow in heating, ventilating, and air-conditioning ducts. To devise a containment strategy it is important to understand the physics of air exchange caused by mechanical means, such as HVAC fans, buoyancy, and external wind con- ditions. There are many building types, and containment must take into account their characteristics. They range 9 from large open-plan buildings, such as stadiums, shop- ping centers, and transportation hubs, to buildings subdivided into modular spaces, such as apartment buildings and offices with separate workspaces. Some buildings are designed as sealed boxes ventilated mechanically, while others are open to the outside air through operable windows and other large apertures. Research is needed to understand the rate at which a contaminant introduced into a specific interior space spreads throughout the building. For contaminants introduced into the intake or ducts of an HVAC sys- tem, the spread and concentration levels throughout the building must be predicted. Exposure within the build- ing from exterior sources must be tied to the perfor- mance of the building envelope and the HVAC system. Understanding of contaminant distribution must then be coupled with an understanding of HVAC sys- tem operations and control systems in order to develop short-term protection strategies. The strategies range from isolation of an individual space to modified opera- tion or shut down of HVAC circulation systems to building evacuation through spaces protected from contaminant intrusion. Protective measures using HVAC shutdown must be evaluated against adverse health effects caused by loss of ventilation over vary- ing time periods. A better understanding of building classes is needed to guide longer-term decontamination efforts as well. This will help define locations for monitoring and sampling based on predicted contaminant dispersal patterns. Ventilation techniques to clear the building of decontamination agents are linked to an understanding of airflow patterns under different HVAC operations. The building materials and furnishings may exhibit long-term emissions of contaminant agents and decon- tamination substances. Relevance of EPA Program EPA has a long history of research both on indoor air quality and on buildings. Some of this work has been intramural, while a significant amount has been extramural support for research at a variety of institu- tions, such as academia to the national laboratories and private industry and organizations. Containment of toxins, released either indoors or outdoors, so that human exposures are avoided or minimized, will clearly benefit from research on indoor air and on build- ings. However, the containment research proposed by the EPA's National Homeland Security Research

10 Center (NHSRC) is more an assembly of existing research ideas than what is needed to answer critical questions in the field. An additional difficulty is the program's three-year limit (to the beginning of fiscal year 2006), which means that a longer-term research agenda cannot be formulated and work on key elements begun until the deadline is renegotiated or work is re-integrated into other EPA research centers and activities without loss of direction or commitment. EPA appears ill-suited for a short-term research program in the area of "active" containment. In the time remaining EPA containment research should have three main objectives: (1) ensure that decontamination strategies account for all potential transport and fate pathways and surfaces in a building to ensure that building decontamination, cleanup, and disposal prac- tices effectively and economically meet the desired criteria; (2) identify and prioritize key long-term building science and containment research needs and determine the role EPA should have in conducting or funding the research; and (3) in collaboration with industrial organizations and other agencies, develop design and performance criteria and standards for con- taminant containment systems and methods. Containment Focus One area of containment covered by EPA's man- date that is of crucial importance to future EPA recom- mendations is the role of containment during decon- tamination and disposal. Containment and disposal will be handled by professionals who will be actively controlling the environment of the building. The ki- netics of containment can be better understood in these controlled circumstances. However, people involved in decontamination and disposal operations will inevi- tably face problems of continued transport of chemical and biological agents, in part through resuspension of previously deposited particles. Understanding these problems and having supporting data and models to address these requirements should be an important, immediate EPA task, and could lead to guidelines in a shorter time frame than work on active containment. Areas of possible EPA focus are HVAC use, aerosol and gas penetration through doors, and inadvertent dis- persal of contaminants (i.e., many of the themes to be studied by EPA in the broader containment framework) specifically in the framework of decontamination and disposal. REVIEW OF EPA HOMELAND SECURITY EFFORTS Another potential research topic is to use airflow and contaminant transport and fate modeling to help examine some of the contamination issues. It is an important task to protect the public by ensuring that decontamination materials are not lost to the environ- ment and to maintain control over the building airflow to ensure that a building is decontaminated as effi- ciently as possible. Airflow circulation within a build- ing can scatter contaminants and decontamination agents in ways that may limit the efficiency of the decontamination effort. Therefore, control is necessary to prevent contaminants from re-entering decontami- nated areas and allow decontamination agents to prop- erly disperse so that toxic materials can be neutralized. Identify Long-Term Research Needs and Determine EPA's Role Many of the containment issues cannot be addressed adequately in a three-year program, in part because of the dearth of past and current research in this field by EPA, other government agencies, and academia. The committee recommends that EPA use the next few years to define a comprehensive long-term research program in this area, and it should be carried out with other organizations knowledgeable in this field, including NIST, DOE, the Department of Home- land Security and academic researchers in the United States, Europe, and Japan. This research should incor- porate the following: · Evaluation of existing multizone airflow and transport models, such as CONTAM (NIST) and COMIS (LBNL), for predicting air and contami- nant movement for application to the problem of understanding the transport and fate of biological and chemical contaminants and decontaminating agents; · Development or evaluation of modeling methods for detailed simulation of contamination dispersal in a single space that can be coupled to a multi- zone model for overall building behavior to specifically include ductwork and vents; Development of containment strategies for im- portant generic building types to include securing safe spaces, evacuation, and decontamination; Coupling of design of HVAC systems and con- trols with potential fast detection technologies for releases in and outside buildings;

ASSESSMENT . Prediction of contaminant dispersal patterns to aid in decontamination; Development of effective means for removing gaseous decontamination products; Characterization of the long-term reemission of contaminates from building materials and fur- nishings; and Development of a building taxonomy for catego- rizing new and existing building stock according to building operations, contaminant transport, and other characteristics. EPA has begun to identify the long-term research needs in this area and whether existing or planned pro- grams in other agencies effectively explore them. The agency has recognized that much of this research will be collaborative, either in funding specific projects with other governmental agencies or funding separate projects that have collaborative or synergistic out- comes. A key activity for which EPA is well posi- tioned is to identify some common research goals and priorities across the various agencies, both as a way of directing EPA research to fill in critical research gaps and as a means establishing interagency cooperation in sharing knowledge, if not research goals. Building Performance Criteria and Standards Projects in the proposed containment Research Implementation Plan (RIP) cover a variety of funda- mental and applied topics on the mitigation of chemi- cal and biological warfare (CBW) attacks. The RIP does not consider one of the most important needs for containment system design: the development of design criteria and performance standards. For example, a comfort air-conditioning system is designed to maintain a particular indoor temperature and humidity given specified occupancy and weather conditions. The indoor conditions are selected to ensure that at least 80 percent of the occupants of the conditioned space will be satisfied with the thermal environment. The parallel analysis for a CBW contain- ment system could be to limit the maximum exposure over a defined period in a given space to a design-basis release of an agent. Considering the spectrum of CBW agents that could be used in a terrorist attack, a design- basis set of agents, both gas-phase and aerosol, may be needed. The performance standards that must be met by a system or component and the design conditions that define the reasonable worst-case scenario under which the system must operate drive the design process. Without them the level of protection afforded by a sys- tem is not well defined. Consequently, the engineers and other professionals responsible for designing and implementing containment systems will not have all of the information they need to cost-effectively ensure the desired performance. Successful pursuit of this objective will require collaboration with agencies outside EPA with high expertise in HVAC systems, air flow analysis, and health effects of chemical and biological exposures. To fully achieve consensus design standards, interaction with organizations such as American Society of Heat- ing, Refrigerating, and Air-Conditioning Engineers and the American Society for Testing and Materials may be required. This is a longer-term project but should be initiated as soon as possible because of its importance. Even interim standards and criteria would be of great value. The vast number of chemical and biological agents, each with its own toxicity signature, and the essentially unbound number of building types, creates a challenge to providing meaningful advice regarding containment during an attack. Conceivably, advice pertaining to HVAC design and operation, while relevant to the con- tainment of chemical and biological agents in the event of contaminant entry into a building, might actually lead to the spread of the contaminant if acted on in either an untimely manner (i.e., after contaminant entry into the building) or in a building context not imagined by the agency in preparing the advice. The understand- ing of how contaminants spread in a building (even how they spread from the opening of an envelope in a very specific room scenario) will need to be gained through extensive experimentation, evaluation of data currently in existence, and generation of data in likely threat scenarios. This understanding will inevitably parallel to some degree the improvement of detection equipment; in any case, such knowledge will need to be acquired over a period of time far greater than the current EPA mandate. DECONTAMINATION A complete national-level program for protection against CBW agents and toxic industrial chemicals (TIC) must also include elements to respond to an attack. It is essential to develop and test technologies to mitigate and decontaminate the effects of a CBW

12 agent or 11(: attack on facilities and people as well as to restore critical facilities after they are attacked. This committee sees EPA's primary role as one of giving the nation an ability to completely restore domestic facilities rapidly and safely after an attack. The committee agrees that the need to develop and implement effective decontamination technologies and health-protective cleanup standards for civilian sce- narios is urgent. The anthrax incidents illustrate impor- tant problems associated with decontamination of civilian-sector facilities. For example, more than three months were required to clean up the Hart Senate Office Building at an EPA cost recently reported to be about $27 million, while the American Media, Inc., headquarters building in Florida, which was first to receive a letter containing a powdered form of anthrax, remains sealed and abandoned to this day. When con- sidering how to address decontamination and cleanup in the public sector it is important to recognize that an effective response must be not only agent specific but site specific as well. The Safe Buildings Program is primarily aimed at indoor facilities such as an office building or hotel, where decontamination of ventila- tion systems is imperative, and public perception issues are extremely important. It also includes a semi- enclosed setting, such as a subway or transportation node. EPA has identified a list of high priority threat agents and the committee has considered those in its assessment below. In general, the committee feels that the Safe Build- ings Program is on target with respect to ongoing and proposed decontamination efforts. It is recognized that a great deal of effort went into making sure that the program was coordinated and not duplicative with ongoing efforts of other agencies and the Department of Energy national laboratories. It is also recognized that this is not an easy task and that some agencies continue to be less than forthcoming with regard to the sharing of information. In the limited time available the Safe Buildings Program has identified some key areas that are not currently being pursued by other agencies but fall in the EPA's jurisdiction and exper- tise. EPA has focused its efforts on four areas, and the committee provides more specific comments for each area below. These efforts should be coordinated with the disposal task to ensure that the resulting waste and by-products are optimized for disposal. Additionally, the committee suggests that more effort and resources be expended on developing an extramural research pro- gram that goes beyond current contractors. Academic REVIEW OF EPA HOMELAND SECURITY EFFORTS laboratories must be encouraged to participate in longer-term research. Development of Standardized Test Protocols for Decontamination Technology Performance The development of standardized test protocols for decontamination technology performance is an impor- tant area for EPA to pursue. In the United States new formulations sold as a biocide must meet EPA approval under the Federal Insecticide, Fungicide, and Rodenti- cide Act (FIFRA). The committee agrees that current testing requirements need to be changed because they are obstacles to the commercialization of new bio- decontamination formulations, many of which are based on oxidizer systems for which the tests were not designed. EPA is aware of this and has formed an inter- agency committee to design more rapid and accurate testing protocols. This activity needs to be accelerated and needs to investigate all types of potential biocides, whether they exist as solutions, foams, gels, gases, or aerosols. One major additional need that should be addressed is the sampling and analysis protocols to be used for cleanup of facilities following a CW or BW incident. Issues involving spore recovery from porous surfaces have not been adequately addressed and could have a major impact on the interpretation of results. Quench- ing should be better explored and standardized since the use of surfactants in a formulation can also impact the consistency of biocide results. EPA has procedures for CW and TIC that are adequate but should be further evaluated for the threat agents that EPA has identified. Some of the sampling and analysis procedures devel- oped in support of the Organization for the Prohibition of Chemical Weapons may be easily implemented for this application. Overall EPA focus should be to develop written standards and protocols that distinguish clearly between requirements for chemical and toxic industrial chemicals and biological threats. Additional guidance and statistical sampling protocols should be developed similar to those developed and used by DOE and EPA for radiological sampling (EPA et al., 1997 ). Systematic Study and Verification of Decontamination System Performance The committee supports the ETV proposed in prin- ciple and feels that this is an important focus area for

ASSESSMENT the EPA's Safe Buildings Program. To be effective, EPA must build off the lessons learned from the anthrax incidents as well as other studies that have been done at Dugway Proving Ground (Larsen, et al., 2002) and elsewhere (Raber and McGuire, 2002) within the last three years. The focus for this evaluation should be on civilian sector issues, where decontamination require- ments are extremely demanding and different from re- quirements for the military. Military testing protocols are aimed at formulations that decontaminate in 30 minutes or less and have not focused on many of the environmental issues facing public sector use. Few controlled protocols exist for testing various building materials, and there is a limited experience base for testing gases, especially in ventilation system decon- tamination. In addition, the potential for resuspension of previously deposited particles must be better under- stood to allow for optimizing decontamination. The indoor air-modeling discussion in the "Containment" section addresses this in more detail. Key test attributes must be determined and weighted by stakeholder group; here again they differ from typi- cal military requirements. What is desired is a method that is noncorrosive, nonhazardous, and degrades to environmentally acceptable residues (i.e., passes EPA methods 8260 and 8270 for volatiles and semivolatiles) and one that works over relatively short decontamina- tion times (hours). Public sector applications also require a formulation that makes maximum contact with surfaces by adhering to walls and ceilings but does not form toxic products by reacting with walls and ceil- ings; is relatively inexpensive and available; has a long shelf life (at least a year); and is easy to deploy and implement. In short, the public sector would be well served with a formulation that takes two days to decon- taminate if the material were nontoxic or degraded to environmentally acceptable by-products. This would not meet military needs. The committee is concerned about the number of products appearing on the market with decontamina- tion claims. EPA is in a good position to evaluate these claims through an effectively structured ETV program. The committee feels that this is an important national role for EPA. Additionally, EPA needs to continue its collaborative working relationship with the Department of Homeland Security with regard to ongoing and planned demonstration programs for decontamination and restoration. 13 Evaluation of the Toxicology of Decontaminating Agents EPA has correctly concluded that there is a need for information on the fate and safe exposure levels of the decontaminating agents themselves, since residues may linger after the building has been decontaminated, and it is important to determine whether it is safe to enter the building and occupy it. More information is needed about the rationale for the choice of compound being studied and for the experimental protocol; based on the available information, the proposed study appears unlikely to meet its desired objectives. Of the possible gas-phase decontaminating agents (e.g., chlorine dioxide, vapor-phase hydrogen peroxide, pare-formaldehyde, and ethylene oxide), EPA has chosen to conduct additional studies only on chlorine dioxide. No rationale for this choice was expressed in the RIP, but it appears to be because chlorine dioxide was used at the Hart Senate Office Building and because it is one of the agents of choice for anthrax. If chlorine dioxide is indeed the agent of choice for anthrax, and if anthrax contamination is among the most likely of the threat scenarios, then additional research on chlorine dioxide is reasonable. On the other hand, if there are other decontaminating agents with similar or higher efficacy than chlorine dioxide, it may be preferable to conduct additional research on these agents (see below). It is not clear which data gaps the proposed studies will consider or how the data would be used in the development of building re-entry guidelines. Before addressing the available data on chlorine dioxide, the relevant exposure standard for re-entry should be con- sidered. The investigators cite the existing NIOSH/ OSHA recommended exposure limit. This is useful as an initial comparison, since the exposure of interest occurs in the workplace, and OSHA is the regulatory agency for workplace exposure. However, the expo- sure of interest would most likely occur primarily among office workers returning to the building. Although this is not a well-defined area of occupational risk analysis, office workers tend to have a lower acceptance of risk than workers in factories that are exposed to industrial chemicals. Office workers are likely to resemble the general population more than factory workers; the lower level of physical activity and the absence of selection for healthy people may remove much of the "healthy worker" effect. Although

14 EPA does not have jurisdiction over the office environ- ment, evaluation of the risk of long-term exposure for office workers should take into account health stan- dards developed for the general public (e.g., the reference concentration PRfC]~. The RfC is defined as "an estimate (with uncertainty spanning perhaps an order of magnitude) of a continuous inhalation expo- sure to the human population (including sensitive sub- groups) that is likely to be without an appreciable risk of deleterious effects during a lifetime" (EPA, 2000~. A second exposure of interest is workers re- entering a building to complete cleanup and replace furnishings. In this case, exposure would be for a lim- ited duration, and short-term guidance values (e.g., for an eight-hour or one-week exposure) would be appro- priate. If there are data gaps in this area, the proposed studies may help in evaluating the toxicity of chlorine dioxide. However, because the proposed high concen- tration of 0.1 ppm is near the "no observed adverse effect" level (NOAEL) for sub-chronic exposure, it is not clear whether the proposed exposure concentrations would provide the necessary information. Higher exposure levels may be needed to identify a NOAEL and a "lowest observed adverse effect" level (LOAEL) for acute exposures. EPA assessed the inhalation toxic- ity of chlorine dioxide in 2000, and has derived an RfC for this chemical (EPA, 2000~. While the RfC is sig- nificantly lower than the REL, due to differences in the methods used, the documentation for the RfC identi- fies key data gaps and uncertainties that should be con- sidered in conducting further testing. In particular, there is uncertainty regarding the NOAEL in the sub- chronic study used as the basis for the RfC. Additional short-term mechanistic studies will not resolve that issue. Another key data gap is the absence of studies of reproductive toxicity through the inhalation route. While gene expression studies are useful for hypothesis generation, they will not provide definitive answers regarding the carcinogenic potential of chlorine dioxide, particularly in the absence of a chronic cancer bioassay. Based on these considerations, the proposed stud- ies may provide useful general information in chlorine dioxide toxicity, but they are unlikely to provide infor- mation within the time frame of interest that is useful to evaluating the health risks of chlorine dioxide following re-entry. More relevant information would be obtained by targeting the testing conditions to deter- mine the NOAEL and LOAEL for the exposure dura- tion of interest (acute or sub-chronic). These standard toxicity studies could be supplemented by mechanistic REVIEW OF EPA HOMELAND SECURITY EFFORTS studies, such as studies designed to improve dosimetry or to establish the mode of action. However, the mechanistic studies should not be the focus of the test- ing, in light of the objectives of the overall Safe Build- ings Program. In summary, the committee recommends that the EPA Safe Buildings Program concentrate on the potential for generation of toxic residues from the interactions of decontamination agents with building materials, furniture, carpets, and other furnishings and cover more than just chlorine dioxide. Understanding the fate of the decontaminants with regard to specific building materials may be useful, but more important is the actual resulting residues and whether they repre- sent a significant health risk. Engineering and Scientific Support and Analysis EPA has identified an initial set of projects to go forward with in this area. The key issue for the EPA Safe Buildings Program will be to come up with the necessary information and supporting processes to be able to make risk-informed decisions when mounting a response. Any kind of decontamination in the public sector requires an understanding of the type of emer- gency restoration needed, including characterization and performance of site-specific risk assessments for potential impact on human and animal health and the environment. These considerations then determine the decontamination or remediation treatment to be imple- mented (Raber et al, 2001). The committee supports the current efforts of EPA to learn from ongoing anthrax fumigations and recom- mends that efforts should include a thorough case study of the Hart Senate Office Building and Brentwood Post Office experiences, focusing on decontamination and disposal. Understanding the real-world conditions and results should provide a baseline for engineering and economic analysis of building decontamination alter- natives. Some of the more recent reports from EPA (2002) and the GAO (2003a,b) also provide a useful perspective and should be incorporated into this effort. "How clean is clean enough?" or put another way, "How clean is safe?" The challenge is to establish target levels of cleanup for the various biological and chemi- cal agents that will meet both regulatory and stake- holder needs and address site-specific parameters as well. The committee feels that two concepts are essen- tial to any discussion of cleanup levels. First, public

ASSESSMENT perceptions and stakeholder issues will drive cleanup requirements. Second, economic drivers and inconve- nience influence stakeholders to accept higher risks. Input from public and regulatory stakeholder bodies is essential when cleanup goals relating to health and risks are set, and when cleanup and decontamination deci- sions are made. The committee believes that successful cleanup requires that risk information be communi- cated to the public throughout the entire process. More- over, the decontamination method that is selected needs to consider the costs of cleanup versus the goal of meet- ing cleanup criteria. Following the anthrax letter incidents in the United States, the importance of economic drivers became clear when cleanup efforts commenced. Although regu- latory guidelines and recommendations for specific air- borne and soil cleanup levels for the G agents (tabun, soman, satin, and cyclohexyl methylphosphonofluridate) and VX exist (U.S. Army, 1999; NRC, l999b, EPA 2000), cleanup levels for biological agents remain problematic (Raber et al, 2001~. To address standards and policies for decontaminating public facilities affected by exposure to harmful biological agents, in particular, anthrax and smallpox, the Department of Homeland Security has commissioned a new study by the National Research Council. The EPA's Safe Build- ings Program is providing useful direction regarding the scope and direction of that study. The NRC com- mittee encourages EPA to continue to work on this as an important interagency effort. The committee also recommends that the EPA Safe Buildings Program consider adding the scope sug- gested below to its proposed research and implementa- tion program. High on the list of important issues is the need for methods to rapidly determine agent-specific viability for effective biological agent decontamination. Current methods, such as PCR technology, tell us what an agent is but not whether it is alive or dead. Current sampling and culturing methods take from one to three days, depending on the agent. Rapid determination of spe- cific agents is the key to restoring critical infrastructure. Some initial research is underway at DOE laboratories, primarily funded by the Defense Advanced Research Projects Agency, to explore the technology gaps related to viability determinations, but this area is not likely to meet all of EPA's needs. The critical advantage of such a method needs to be integrated into EPA's current approach for biological decontamination. It is important to understand the potential for natural 15 attenuation for both chemical and biological warfare agents. It is well known that such factors as ultraviolet light from the sun can kill vegetative cells and certain other biologicals. Some literature is available for spore and cell survival in outdoor environments, but infor- mation is limited for indoor environments, and con- trolled environmental studies are lacking (Setlow, 2000~. Research on Bacillus anthracis shows that the spores suffer heavy mortality over time up to 90 per- cent per year but remaining spores can germinate and grow. Nonsporulating vegetative cells that require high water activity survive longer in a dormant state. Thus, it becomes important to study the conditions required for germination, growth, and sporulation in enclosed and semi-enclosed environments, especially as a func- tionoftemperature,humidity,andtime. Again, under- standing the limits of natural degradation potential can aid in determining effective decontamination strategies. With regard to CW agents, early work done by Lawrence Livermore National Laboratory researchers in cooperation with British scientists at Porton Down, U.K., studied natural degradation of the G agents and VX at a concentration of 5 g/m2. Tests were conducted in sandy soil, silty soil, and on silicon rubber gasket material. Within three days in a humid environment the chemical agents degraded to nondetectable levels, except for the tests on rubber gasket material (Raber et al., 2001~. Thus, the expectation is that outdoors and at least in soil, natural degradation of chemical warfare agents can be effective. Understanding this for semi- enclosed environments may also aid in determining effective decontamination strategies. Long-Term Research Needs and EPA's Role The EPA Safe Buildings Program needs to help set the stage for a longer-term research agenda for de- contamination and restoration. EPA has identified three areas that are required for longer-term success. These are (1) development and optimization of novel (and improved) decontamination methods; (2) addi- tional evaluations of existing decontamination meth- ods and systems; and (3) development of methods for high-value materials (e.g., museum holdings, national treasures). The committee agrees with EPA's longer-term recommendations. The committee evaluated current technologies to identify significant decontamination technology gaps for applications in the public sector. The committee recommends that a longer-term decon-

16 lamination and restoration research program, coordi- nated with other agencies, include the following: 1. Technologies, systems, and studies to better char- acterize the extent of chemical and biological con- tamination resulting from a terrorist attack using CBW agents or TICs. · Standards Development studies to deter- mine standards for cleanup levels for CBW and TIC materials for various types of contami- . ~ ·. - · . . . - . . nated tacllltles and demographic groups. Sampling Methodology Development tech- nologies to increase sampling efficiency for CBW agents in facilities and surrounding areas. Agent and Decontaminate Studies studies to develop a better understanding of transport, robustness, and viability of CBW agents and the potential for toxic residues resulting from the decontamination process. 2. Development of methods for better, cheaper, safer, and faster decontamination of facilities and other contaminated areas. · Decontamination of Sensitive Equipment and Other Items technologies and methods to decontaminate other sensitive equipment and sensitive items (e.g., computing equlp- . . meet, paintings). Decontamination of Hard-to-Reach Places- technologies and methods to decontaminate hard-to-reach places such as the interior of ductwork and the area above ceiling tiles. These technologies should include less toxic vapor and gas decontaminants and methods that can be employed and utilized with less infrastructure requirements than chlorine dioxide. Decontamination of Exposed Surfaces and Wide Areas technologies and methods to effectively decontaminate exposed surfaces in facilities and surrounding areas (i.e., special- ized reactive and sealant materials in paints or coatings that could adhere to high places and require no cleanup and methods to decontami- nate; foam, gels and liquids that adhere to ver- tical surfaces and ceilings. · Biological Mechanistic Decontamination Studies studies to determine mechanisms of spore kill and other related effects. REVIEW OF EPA HOMELAND SECURITY EFFORTS 3. Restoration Systems Development and Evalua- tion the study and development of systems and tools to better understand, to plan, and to imple- ment the restoration process (e.g., identification of preventative measures for sealing and cover- ing porous surfaces with materials, such as epoxy paint or stainless steel sheeting, to create smooth surfaces that are easier to decontaminate). This includes the verification of decontamination prod- ucts and the optimization of the process to be used. It is clear from the efforts under way to use chlo- rine dioxide and vaporous hydrogen peroxide that there is much scientific data lacking (e.g., effectiveness as a function of temperature, humidity, time, materials) that is vital to an efficient and effective decontamination. Currently, huge infrastructure needs (e.g., source gen- eration, air-tight tenting of building, negative pressure apparatus, circulation pumps, scrubbers, detection apparatus) are required and this causes a significant delay in the restoration of contaminated facilities. A proper metric for this program would be to decontami- nate and restore a building similar to the Hart Senate Office Building in less than one month and preferably two weeks. DISPOSAL The proposed strategy and research projects reflect EPA's expertise in handling hazardous materials dis- posal issues, its experience in responding to the recent anthrax decontamination effort, and its overall experi- ence in hazardous waste cleanup through implementa- tion of Superfund cleanup and removal actions. Specific research and implementation projects focus on disposal options that include thermal or incineration and landfill. The grass-roots approach EPA is taking to involve impacted regulatory agencies, manufacturers, emergency responders, and facility operators is a sound approach. Both thermal treatment and incineration have the advantage of addressing both hazard and waste reduction issues. The need to under- stand the matrix effects of incinerating bulk items to destroy CBW agents is a necessary step toward using this technology. Developing methods to test incinera- tor emissions for the agents being treated is essential for effectively using thermal treatments for CBW agents and meeting public perception issues and stake- holder demands. Looking at the viability and surviv- ability of organisms of concern in landfills is also

ASSESSMENT necessary to allow for disposal of BW materials directly into landfills. Research focused on the longevity of Bacillus anthracis spores shows that 90 percent of spores in soil die within 50 years (Sneath, 1962~. How- ever, surviving spores can remain viable for 300 years. Understanding this issue and the associated impact is key to an effective disposal strategy. This committee supports EPA's approach to the proposed projects on disposal. However, it also rec- ommends that EPA consider the following in its CBW disposal options: 1. Thermal treatment and incineration may not be viable approaches in many states where air qual- ity issues are a concern. For example, California does not have a permitted hazardous or medical waste incinerator and only has three municipal facilities that use incineration as a permitted waste transformation process. There are only a handful of operating incinera- tors around the country. Investigations as to whether these few incinerators can handle the bulky items identified in the project proposals need to be included in EPA's consideration. The project proposals also include streamlining the permitting process for thermal treatments. However, they do not include issues related to whether there are technologies that can economi- cally meet air quality standards and whether pub- lic perception will allow such facilities to be sited even if the permitting process were streamlined. Thermal treatment temperatures that effec- tively kill any remaining anthrax spores are typi- cally higher than those for standard medical waste incineration.7 To render biological warfare agents completely harmless, dry heat requires two hours of treatment at 160 degrees C. If steam is used at 121°C and 1 atm of overpressure (15 psi), the time may be reduced to 20 minutes, depend- ing on volume (Office of the Surgeon General, 1997~. Therefore, these incineration and thermal treatment proposals should include a focus on the 7Title 17, California Code of Regulations, Division 1, Air Re- sources Board, Chapter 1 Air Resources Board, Subchapter 7.5. Airborne Toxic Control Measures, Section 93 104, Dioxins Air- borne Toxic Control Measure Medical Waste Incinerators 17 efficiency of different temperature treatments for the specific CBW agents. 2. A criterion needs to be developed for disposing of decontaminated materials in municipal land- fills, which would allow more options with respect to facilities able to take decontaminated CBW waste. For example, in California, if crite- ria were available to determine that wastes are no different than any other municipal waste, includ- ing waste contaminated with sewage, CBW wastes could be disposed in an appropriate Class III landfill.8 9 The key technical question for EPA to answer is whether the decontaminated material meets the criteria of any other municipal wastes. Answering this question positively could set baseline criteria for a decontamination standard and should be a key factor in setting goals and objectives for EPA's decontamination research program discussed in EPA' s Research Implemen- tation Plan. 3. EPA also identifies thermal treatments as a dis- posal option; however thermal treatments are also decontamination methods. In fact, the projects seem to be proposing thermal treatment as a way of treating residual contamination before dispos- ing the waste products to air and landfill. The de- contamination and disposal strategies and proposals should be better coordinated. If the material is to be decontaminated, then decontami- nation methods that will meet municipal landfill criteria as discussed above should be identified. 4. The committee recommends that EPA have a strategy related to methods development for sta- bilizing remaining hazardous waste materials so that the materials may be sent to a landfill rather than impose an incineration or thermal treatment approach. Such items as air handling filters and other more porous materials may be more difficult to decontaminate. It will be important to evaluate Title 27, California Code of Regulations, Environmental Pro- tection Division 2, Solid Waste 9Title 14, California Code of Regulations, Natural Resources Division 7, California Integrated Waste Management Board per- taining to nonhazardous waste in management in California.

18 REVIEW OF EPA HOMELAND SECURITY EFFORTS some of the more recently developed resin stabili- zation methods for nuclear-contaminated material in the context of the Safe Buildings Program. Some such methods may stabilize remaining spores and be applicable to treatment for toxic industrial chemicals, including CW materials. The committee encourages EPA to discuss some of the approaches used by the DOE national labo- ratories where they have been successful in stabi- lizing difficult wastes to meet land disposal restrictions and dispose of the wastes directly in a landfill (Tyson and Schwendiman, 1995; Bowers et al., 1995; Gates-Andersen et al., 2003~. 5. The EPA's proposals discuss liquid wastes gen- erated as part of decontamination efforts, but they do not include research regarding disposal of this waste or whether there is a need to address liquid waste disposal options. For example, can these types of waste be discharged to a publicly owned treatment works (POTW) without interrupting treatment processes or causing exposures to workers at the POTW. In some cases the decon- taminated wastewater might be characterized as hazardous for toxicity. It is important to deter- mine whether the current hazardous waste dis- posal methods are indeed adequate for handling the liquid waste stream created by decontaminating CBW-contaminated materials. Approaches should be evaluated for stabilizing any remaining hazardous liquid wastes that are generated so that they can meet landfill toxicity characteristic leaching procedure (TCLP) disposal criteria. Such approaches should be incorporated into EPA's overall strategy. In summary, EPA should develop guidance docu- ments and matrixes for emergency managers on what the best disposal options would be as a function of potential impacts on environmental media (e.g., air, water, land) receiving the different types of waste material. EPA also needs to include an analysis of com- peting and overlapping federal, state, and local regula- tions and ordinances that might prevent the application of certain disposal technologies. This would be the key to streamlining disposal procedures.

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The report examines the Environmental Protection Agency’s three-year plan for a comprehensive response to a chemical or biological attack on a civilian or public sector facility. The report states that EPA has correctly identified the essential major research areas (detection, containment, decontamination, and disposal) but calls for an initial focus on decontamination and disposal efforts and a longer term research program.

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