6
Report Summation and Recommendations

As outlined in Chapter 1 of this report, the U.S. Army’s Chemical Materials Agency and its predecessor organizations have been engaged in the demilitarization of the nation’s stockpiles of chemical weapons for over a quarter of a century. CMA recently completed destruction of the chemical agents and associated munitions stored at six of eight continental U.S. storage facilities as well as chemical weapons deployed overseas, which were transported to Johnston Atoll, southwest of Hawaii, and demilitarized there. These CMA activities have successfully destroyed 90 percent of the nation’s chemical weapons inventory

The remaining 10 percent of the chemical weapons stockpile is stored at two remaining continental U.S. depots, in Lexington, Kentucky, and Pueblo, Colorado. Their destruction has been assigned to a separate U.S. Army organization, the Assembled Chemical Weapons Alternatives (ACWA) Element. The last two chemical weapons disposal facilities, the Blue Grass and Pueblo Chemical Agent Destruction Pilot Plants, are currently under construction. ACWA is charged with destroying the Blue Grass and Pueblo stockpiles without using the multiple incinerators and furnaces used at the five CMA demilitarization plants that dealt with assembled chemical weapons—munitions containing both chemical agents and explosive/propulsive components.

The CMA disposal facilities that processed assembled chemical weapons used an array of furnaces both to destroy drained chemical agents and to decontaminate or destroy other agent-contaminated munitions components and secondary waste materials. However, the two ACWA demilitarization facilities are congressionally mandated to employ noncombustion-based chemical neutralization processes to destroy chemical agents and will not have large furnaces to decontaminate or destroy secondary waste materials. This constraint motivates an interest in analytical methods that can quickly and reliably identify and characterize agent-contaminated materials. Detecting and characterizing agent-contaminated structural surfaces are also a priority, both during agent changeover operations (BGCAPP only) and during facility closure activities, when agent disposal facilities must be decontaminated before demolition (both BGCAPP and PCAPP). Since chemical weapons disposal operations are currently not expected to start at PCAPP until 2015 and at BGCAPP until 2020, there is at least a 2- to 7-year window to assess, develop, and procure advanced analytical technology that could be used in both agent processing and closure activities at each site.

Currently available methods to monitor chemical agent contamination of both secondary waste and structural components (initially discussed in Chapter 2 and more



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6 Report Summation and Recommendations As outlined in Chapter 1 of this report, the U.S. Army's Chemical Materials Agency and its predecessor organizations have been engaged in the demilitarization of the nation's stockpiles of chemical weapons for over a quarter of a century. CMA recently completed destruction of the chemical agents and associated munitions stored at six of eight continental U.S. storage facilities as well as chemical weapons deployed overseas, which were transported to Johnston Atoll, southwest of Hawaii, and demilitarized there. These CMA activities have successfully destroyed 90 percent of the nation's chemical weapons inventory The remaining 10 percent of the chemical weapons stockpile is stored at two remaining continental U.S. depots, in Lexington, Kentucky, and Pueblo, Colorado. Their destruction has been assigned to a separate U.S. Army organization, the Assembled Chemical Weapons Alternatives (ACWA) Element. The last two chemical weapons disposal facilities, the Blue Grass and Pueblo Chemical Agent Destruction Pilot Plants, are currently under construction. ACWA is charged with destroying the Blue Grass and Pueblo stockpiles without using the multiple incinerators and furnaces used at the five CMA demilitarization plants that dealt with assembled chemical weaponsmunitions containing both chemical agents and explosive/propulsive components. The CMA disposal facilities that processed assembled chemical weapons used an array of furnaces both to destroy drained chemical agents and to decontaminate or destroy other agent-contaminated munitions components and secondary waste materials. However, the two ACWA demilitarization facilities are congressionally mandated to employ noncombustion-based chemical neutralization processes to destroy chemical agents and will not have large furnaces to decontaminate or destroy secondary waste materials. This constraint motivates an interest in analytical methods that can quickly and reliably identify and characterize agent-contaminated materials. Detecting and characterizing agent-contaminated structural surfaces are also a priority, both during agent changeover operations (BGCAPP only) and during facility closure activities, when agent disposal facilities must be decontaminated before demolition (both BGCAPP and PCAPP). Since chemical weapons disposal operations are currently not expected to start at PCAPP until 2015 and at BGCAPP until 2020, there is at least a 2- to 7-year window to assess, develop, and procure advanced analytical technology that could be used in both agent processing and closure activities at each site. Currently available methods to monitor chemical agent contamination of both secondary waste and structural components (initially discussed in Chapter 2 and more 113

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114 ASSESSMENT OF AGENT MONITORING STRATEGIES FOR BGCAPP AND PCAPP thoroughly in Chapter 3) were developed at CMA disposal facilities and will be adopted for use at the ACWA facilities. While they have allowed safe waste processing and closure activities, these methods are time consuming and indirect, generally relying on vapor-phase agent measurements over confined surfaces, rather than direct detection of surface contamination. Chapter 3 also summarizes the characteristics and estimated magnitudes of potentially contaminated secondary waste streams that will be generated during both process operations and closure activities at BGCAPP and PCAPP. Based on current understanding of probable agents/munitions processing and closure activities at the ACWA facilities, six scenarios developed by the committee are presented in which real- time agent contamination measurements on surfaces or bulk materials might allow more efficient, and possibly safer, operations. The recent rapid development of ambient ionization mass spectrometric techniques for real-time surface and bulk materials analyses is reviewed in Chapter 4. An assessment of the capability of these techniques to provide highly sensitive and specific real-time measurements of the chemical agents relevant to ACWA demilitarization activities is presented, and implementations of the technologies relevant to selected Chapter 3 scenarios are evaluated, in Chapter 4. The ability of these methods to perform real-time chemical agent vapor concentration measurements is also explored. Chapter 5 assesses the statistical measurement challenges inherent in both current vapor-phase chemical agent monitoring and potential ambient ionization surface/bulk agent contamination measurements. Statistical constraints on real-time sampling methods pertinent to the agent contamination scenarios presented in Chapter 3 are discussed and assessed in Chapter 5. Two appendixes associated with Chapter 5 present statistical methods that can be used to develop and evaluate potential chemical agent contamination measurement strategies. The remainder of this chapter summarizes salient points from Chapters 2 to 5 in conjunction with a reiteration of the findings and recommendations presented in those earlier chapters, and it concludes with an assessment of the potential value of ambient ionization mass spectrometry for prospective ACWA chemical weapons demilitarization activities. FINDINGS AND RECOMMENDATIONS The initial finding of this report (2-1) points out the indirect nature of the methods that CMA developed for detecting and assessing chemical agent contamination of materials, and that ACWA plans to use during agent processing and plant closure operations. Closely related Finding 2-2 recognizes a recent CDC recommendation that CMA establish a health-based surface agent contamination hazard level for use with wipe samples of agent-contaminated surfaces interrogated during closure activities. The committee observes that such a standard, coupled with new capabilities for real-time direct surface contamination measurements, could also serve ACWA well. Finding 2-1. The prevalent Army demilitarization activity methods of detecting materials' surface contamination involve enclosing materials and monitoring headspace

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REPORT SUMMATION AND RECOMMENDATIONS 115 agent concentrations. These are indirect methods that can determine if significant levels of agent are present in the enclosed volume; surfaces are not directly monitored. However, vapor detection does not identify the location nor quantify the level of contamination on surfaces within the test volume. Finding 2-2. No CMA or ACWA standards have been established for surface contamination similar to the airborne agent concentration exposure limits, from which vapor screening levels have been adopted. If accepted by the CDC and relevant state regulators, a health-based agent-contaminated surface hazard level measured in mass per unit area by a new, direct surface contamination measurement technology and suitable agent-contaminated surface calibration standards could be useful in clearing secondary waste materials during ACWA disposal operations and/or structural materials during closure. However, reliable agent-contaminated surface calibration standards may be difficult to produce. Based on its review in Chapter 3 of available estimates of anticipated secondary waste production at both PCAPP and BGCAPP, the committee notes that the two sites currently tabulate anticipated waste streams using disparate waste category designations. Finding 3-1. The waste category designations used for tabulating waste streams at the Pueblo Chemical Agent Destruction Pilot Plant and the Blue Grass Chemical Agent Destruction Pilot Plant differ, thus making waste management comparisons between the two facilities difficult. For example, at one site the waste quantity estimates list waste demilitarization protective ensemble suits separately, but at the other such waste is included in halogenated plastic waste. Accordingly, the committee recommends: Recommendation 3-1. The Program Executive Officer for Assembled Chemical Weapons Alternatives should consider implementing a uniform set of waste category designations for use at both the Blue Grass Chemical Agent Destruction Pilot Plant and the Pueblo Chemical Agent Destruction Pilot Plant to facilitate the transfer of knowledge and lessons learned between sites. After also reviewing the major role that demilitarization protective ensemble (DPE)-suited entries into agent-contaminated weapons processing areas are expected to play in pacing ACWA facility weapons disposal, the committee finds: Finding 3-2. Any new monitoring method that could efficiently and reliably locate and quantify agent contamination may make decontamination activities more efficient by: Enabling faster identification of leaking munitions and decontamination of machinery, potentially reducing the number and/or duration of DPE-suited entries during normal plant operations, agent changeover periods, and closure activities; Reducing the total amount of secondary waste;

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116 ASSESSMENT OF AGENT MONITORING STRATEGIES FOR BGCAPP AND PCAPP Speeding waste disposal; and Minimizing worker exposure. Consideration in Chapter 3 of the need to identify and assess potential agent contamination in occluded spaces during agent changeover or closure activities led the committee to find: Finding 3-3. A local, real-time agent monitoring system capable of monitoring surfaces might enhance the effectiveness of occluded space survey teams by identifying problematic occluded spaces and identifying other sources of contamination, possibly reducing the time necessary to conduct agent changeovers or facility closure. After reviewing (in Chapter 3) the likelihood of agent contamination of porous materials such as concrete, as well as prior NRC committee recommendations (NRC, 2007, 2008a), the committee also finds: Finding 3-4. Materials with inherent porosity can readily adsorb or absorb agent and present a monitoring challenge for headspace vapor measurement methods. Chapter 4 presents a thorough overview of the measurement principles, technology variations, and analytical capabilities of recently developed ambient ionization mass spectrometry techniques. Based on information about and analyses of the technology's capabilities, the committee finds: Finding 4-1. When compared to existing vapor monitoring (DAAMS and MINICAMS) measurement strategies, ambient ionization mass spectrometry provides the following capabilities for detection and quantitation of chemical agents and their degradation products (see also Table 4-3): Exceptional sensitivity and selectivity. Direct measurements from vapor, liquid, or solid samples. Real-time measurement with minimum response times of milliseconds to seconds. Multiagent detection capability and degradation product monitoring. Measurements of variations in spatial and temporal concentration. Finding 4-2. DART, DESI, and other emergent ambient ion sources can be considered for surface analysis. A range of different technologies can be employed for liquid and ambient vapor ionization. Both DESI and DART are able to sample and identify molecular species on surfaces in real time (less than 5 sec per measurement). Finding 4-3. DESI requires a solvent, usually an organic or organic/water mixture, with a few percent acid to enhance protonation of the target molecules. A high-velocity gas flow concentric with the electrospray tip directs charged droplets toward the sample. This plume can easily scatter liquid and solid material. Further dispersal of chemical agent that

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REPORT SUMMATION AND RECOMMENDATIONS 117 might lead to contamination of adjacent surfaces, especially the mass spectrometer, is not a desirable result. Finding 4-4. DART, using a controlled flow of heated gas typically comprising helium or a nitrogen/helium mixture, provides the capability to heat, evaporate, and subsequently ionize the target species with modest target agent dispersal. Furthermore, it is possible to vary the temperature of the flowing gas to carry out temperature programmed desorption, observing in turn species with a wide range of volatilities. In addition to surface sampling capabilities, the DART source is an efficient atmospheric pressure chemical ionization source and hence can ionize and detect species at low concentrations in the vapor phase. Finding 4-5. The platform configuration most likely to satisfy the analytical needs put forward in the various scenarios in Chapter 3 for different waste streams consists of a cart-mounted or handheld mass spectrometer equipped with a modified interface to accommodate a special remote sampling wand, a surface ambient ionization source combined with a vapor ambient ionization source, and any sampling accessories. Ambient ionization mass spectrometry systems backed by an uninterrupted power supply will allow portability between different rooms or site areas without breaking vacuum. Careful attention to instrument shielding and sampling wand design and implementation can reduce the possibility of agent contamination during instrument use. Finding 4-6. At the highest levels of sensitivity, detection of chemical agents requires high mass resolution to distinguish the agents from isobaric trace species with the same nominal mass. A minimum resolution of 10,000 (m/m, where m is the full width at half maximum) is required for this purpose. This value can be accomplished with an orthogonal sampling time-of-flight (TOF) mass spectrometer incorporating a reflectron. High-end instruments of this type can provide mass resolution 1.5-5 times this value and would be preferable if not for their cost and size. Selective reaction monitoring, in which an ion structure is confirmed by specific fragmentation pathways, can avoid false positives for chemical agent identification without requiring high mass resolution. While this can be accomplished with newer TOF-TOF instruments, the suggested mass analyzers are either a triple quadrupole or a linear ion trap. These findings inform the following recommendations: Recommendation 4-1. While both DESI and DART have been demonstrated to have excellent sensitivity for detecting chemical agents in liquids and on a wide range of surfaces, if only one technique is adopted, DART is preferable for the potential ACWA utilization scenarios, based on its lower dispersion of target species, utilization of a gas rather than a liquid as the working medium, and ability to efficiently ionize and detect trace levels of species in the gas phase. A DESI system with a cover shield to intercept dispersed contaminants may also be applicable. The use of instrument shields to minimize agent contamination would have to be investigated during instrument test and evaluation activities.

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118 ASSESSMENT OF AGENT MONITORING STRATEGIES FOR BGCAPP AND PCAPP Recommendation 4-2. The Army should specify a list of requirements for an ambient ionization mass spectrometer system that would implement analytical capabilities specifically designed to respond to the challenges summarized in the different scenarios described in Chapter 3. Suggested mass analyzers are either triple quadrupole or linear ion trap, because both can be operated in selective reaction monitoring modes for validation of agent identification and reduction of false positives without requiring high mass resolution. The instrument's atmospheric pressure interface should be fitted with an optionally heated transfer line designed to serve as a multifunction sampling wand. Ionization can occur either at the end of the wand (desorbed surface species or ambient vapor) or at the atmospheric pressure sampling orifice of the mass spectrometer (vapor). In the first case, ions are transported, whereas in the second case, neutrals are generated and then transported to the ionizer. A system employing a wand should be tested for the efficacy of the analytical methodology to trace an expanding vapor plume back to its source. This would be especially beneficial in identifying and locating Type I and possibly Type II occluded spaces (see Box 3-3) as well as in identifying leaker munitions in both storage and processing areas. The overall ambient ionization mass spectrometric system should be portable, either cart-mounted or handheld, for maximum utility. Recommendation 4-3. The sampling wand should accommodate a variety of sampling modes and interchangeable ion sources: A compact DART (and possibly DESI) source that can be mounted either at the end of the wand, with ions sampled through the wand, or directly on the mass spectrometer, with neutrals sampled through the wand. A thermal neutral desorption mode where hot gas is blown toward the surface and the desorbed neutrals are collected by a suction interface that directs them toward the ionization source attached to the mass spectrometer. A gas sampling mode where ambient air is drawn into the interface but no gas is blown to any surfaces. A sampling port that allows the user to manually wipe an area and either place the wipe directly on the sampling wand or insert it through the port into the plasma of the DART source attached to the mass spectrometer. A high-sensitivity air monitoring mode where a solid-phase microextraction fiber is exposed to the vapor to be sampled and directed into the plasma source. A high-sensitivity surface sampling mode where a polydimethylsiloxane membrane is attached to the surface to be sampled for an extended period of time and then exposed directly to the plasma for desorption ionization. A liquid sampling mode that allows manual sampling of a liquid pool or drip. Ambient ionization mass spectrometry methods achieve their high level of sensitivity by utilizing highly efficient chemical ionization processes. Based on the committee's analyses of the ion chemistry of the chemical agents present in ACWA site weapons and published studies of mass spectrometric detection of these agents presented in Chapter 4, the committee finds:

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REPORT SUMMATION AND RECOMMENDATIONS 119 Finding 4-7. The chemical agents VX, GB, and HD have markedly different acid-base properties in the gas phase. This is reflected in the quasimolecular ions observed and monitored when DART is employed for their detection. Only VX is observed as the protonated molecular ion, GB is detected as an adduct with ammonium ion, and HD is detected as the oxidized sulfoxide derivative, which has a proton affinity significantly higher than that of the parent molecule. While it has been demonstrated that all three species can be detected with high sensitivity in laboratory studies using the same instrumental conditions, it is not obvious that this multiagent detection capability will be possible when this experimental methodology is deployed and used in working environments. For example, ammonia in laboratories can originate from human breath and would likely not be as abundant in Class A environments where workers are in DPE suits and might have to be added to the sampling flow. In addition, the extent of sample oxidation in ambient ionization sources is known to be dependent on source operating conditions and environmental factors such as the relative humidity. Chapter 3 presents several scenarios that describe potential uses of ambient ionization mass spectrometry that might expedite agent processing or closure activities. If ambient ionization mass spectrometry methods are to be used in these scenarios or other situations, they must be tested and evaluated prior to implementation. With this requirement in mind the committee finds and recommends: Finding 4-8. MINICAMS are designed to monitor relatively large areas and alarm when levels exceed a specified limit. Although regarded as near-real-time detectors, they typically require 5 to 10 min for a single analysis. This is not particularly efficient when attempting to locate and define an area of agent contamination. For example, when exposure to agent is possible, MINICAMS sampling ports are moved over worker DPE suits to see if agent levels exceed 1 VSL, pausing in four quadrants to take a measurement. This is a time-consuming procedure. Recommendation 4-4. Procedures developed and optimized in laboratory environments for the real-time detection of chemical agents using ambient ionization mass spectrometry should be verified in all working environments where they are likely to be deployed, using actual sample materials (e.g., activated charcoal from filter beds and worker masks, DPE suit material, and polymer-coated concrete). Recommendation 4-5. Procedures should be developed for using ambient ionization mass spectrometry (e.g., DART, large-area DESI) to check worker DPE suits for contamination when workers are exiting Class A work areas. This approach could greatly reduce the time required for this activity, including verification of the effectiveness of decontamination procedures carried out prior to DPE suit removal when agent is detected. The potential ambient ionization mass spectrometry application scenarios discussed in Chapters 3-5 rely on only relative detection of agent contamination on or in condensed materials. There is no requirement that absolute quantification of surface or bulk agent concentrations be determined. Currently, neither CMA nor ACWA has

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120 ASSESSMENT OF AGENT MONITORING STRATEGIES FOR BGCAPP AND PCAPP developed a health-based surface agent contamination hazard level (see Finding 2-2), and so clearing contaminated waste by showing that surface contamination is below a defined level is not currently feasible. ACWA is planning to clear primary liquid waste based on measuring bulk agent chemical concentrations using other analytical techniques. Reliable quantification of either surface or bulk agent contamination requires suitable calibration standards for any analytical technique, including ambient ionization mass spectrometry. Even if absolute agent surface contamination level measurements are not required, reliable bulk and surface agent contaminated standard materials are valuable to check ambient ionization mass spectrometry instrumental sensitivity and time response. Based on the discussions of these issues presented in Chapter 4, the committee finds and recommends: Finding 4-9. Mass spectrometric detection methodology is able to provide relative quantification of analyte species, including chemical agents, over several orders of magnitude with excellent linearity between concentration and response for both gas- and liquid-phase analytes with appropriate sampling and ionization methods. Absolute quantification can be provided with appropriate reference standards. This is true of the ambient ionization mass spectrometric methods as well. However, quantifying amounts of target species on surfaces and adsorbed in solid substrates is more problematical. Recommendation 4-6. The Army should develop reference standards to permit calibration of mass spectrometric instruments using DART (or other deployed ambient ionization sources) for analysis of chemical agents in gases and liquids. In the case of gas-phase samples, it would be useful to develop a reference standard that reliably provides a vapor-phase concentration equal to 1 vapor screening level of the target agent, both to quantify measurements and to verify acceptable performance during critical operations. Even though they may be less reliable for quantitative analysis, calibration standards and procedures should also be developed that ensure acceptable sensitivity for detection of trace amounts of agents on relevant surfaces. To demonstrate the application of statistical data analysis techniques on a relevant ambient ionization data set, in Chapter 5 the committee presents analyses of DART measurement data for chemical agent concentrations in distilled water and 2-propanol (VX) and methylene chloride (GA, GB, and HD). These data were acquired at the Army's Edgewood Chemical Biological Center and are summarized in Nilles et al. (2009). Based on these analyses, the committee finds as follows: Finding 5-1. New analytical methodologies (e.g., DART) have been demonstrated for relevant nerve agents (GB and VX) and blister agents (HD, HT, H) in simple liquid matrices (deionized water, isopropyl alcohol, methylene chloride). Similar data for relevant surfaces (e.g., metal, concrete, activated carbon, plastics, and iron oxide) are sparse. Finding 5-2. Good precision and accuracy for DART techniques have been established for liquid matrices through the use of an internal standard. Challenges for development of internal standards for surface measurements include the presence of potential interferents;

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REPORT SUMMATION AND RECOMMENDATIONS 121 heterogeneous solid matrix properties; and heterogeneous analyte distributions and difficulty in introducing any internal standards. Development of internal standards for more homogeneous liquid and gas-phase matrices is more straightforward. The development of an internal standard may or may not be practical for some surface analysis applications at the Pueblo Chemical Agent Destruction Pilot Plant or the Blue Grass Chemical Agent Destruction Pilot Plant. In the absence of an internal standard, the precision of the quantitative measurements may decrease. Based on these findings, the committee recommends: Recommendation 5-1. The use of DART, DESI, or related new analytical methodologies for surface area measurements at the Pueblo Chemical Agent Destruction Pilot Plant or the Blue Grass Chemical Agent Destruction Pilot Plant requires that the quality of measurements be determined and related calibration studies be performed for relevant matrices. Recommendation 5-2. In the absence of an internal standard for surface measurements, the uncertainty in the measurement technologies (e.g., DART and DESI) should be established. Based on its review early in Chapter 5 of the statistical analysis procedures presented in the ACWA Chemical Agent Laboratory and Monitoring Quality Assurance Plan (LMQAP) (U.S. Army, 2011b) and the role of valid upper confidence limits in compliance monitoring as discussed later in the chapter, the committee finds as follows: Finding 5-3. The published protocols for statistical procedures for compliance monitoring by the Assembled Chemical Weapons Alternatives program (i.e., in the draft Laboratory Monitoring Quality Assurance Plan, Rev. 0, April 4, 2011) contain insufficient detail to provide guidance for compliance monitoring. The ambiguity of current publicly available documentation suggests that quantification of statistical variability has the potential to be inaccurate. Such inaccuracies may result in difficulties such as unnecessary destruction of uncontaminated waste and/or failure to identify contaminated waste. Accordingly, the committee recommends: Recommendation 5-3. The Assembled Chemical Weapons Alternatives program should reexamine existing protocols planned for compliance monitoring at PCAPP and BGCAPP and means for incorporating increased statistical rigor in the assessments to be performed. The committee briefly addresses aspects of bias, precision, and detection limits of real-time analytical instrumentation, finding that computer software programs, when appropriately validated as recommended, can play a role in providing reliable real-time ambient ionization mass spectrometry measurements.

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122 ASSESSMENT OF AGENT MONITORING STRATEGIES FOR BGCAPP AND PCAPP Finding 5-4. Reliable real-time computer programs able to interpret real-time chemical analyses enable instruments (generally using proprietary software) to convert intensity measurements to concentrations of agent and potential interferents. Recommendation 5-4. Instrument software for use with ambient ionization mass spectrometry should be reviewed to ensure that it meets appropriate validation and verification criteria. This software should be tested by using simulated data to test different measurement scenarios (e.g., all data below detection limits, at detection limits, mixtures, hot spots, and so on). Chapter 5 evaluations of statistical sampling issues for materials potentially contaminated by chemical agent led to the following finding and recommendation: Finding 5-5. In some cases, analysis of direct surface and/or materials wipe sampling may complement or replace vapor screening level analysis, allowing more efficient and cost-effective closure operations. Recommendation 5-5. If direct surface and/or materials wipe sampling analysis methods are adopted, appropriate statistical methods for characterizing the extent of contamination of surfaces, machinery, and/or materials should be employed. Following the extensive discussion of statistical sampling plans in Chapter 5, the committee finds and recommends: Finding 5-6. The use of statistical sampling will improve agent contamination detection and quantitation. For near-real-time measurement technologies, sequential sampling may be particularly valuable. Specific sampling plans will depend on the geometry of the contaminated area, contaminant spatial variability, and the goal of the measurement process. Finding 5-7. The successful application of any measurement technology is a function not only of its capabilities, but also of the ultimate use of the data generated. The context and purpose of the measurements will determine the sampling scheme, precision, and accuracy required. Recommendation 5-6. The Assembled Chemical Weapons Alternatives (ACWA) staff should have access to sufficient statistical expertise to develop effective sampling protocols for any application of ambient ionization monitoring. Once the resulting expert sampling protocols have been developed, ACWA headquarters monitoring staff or their contractors should then proceed to develop detailed standard operating procedures to guide monitoring technicians.

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REPORT SUMMATION AND RECOMMENDATIONS 123 CONCLUSIONS As reflected in the recommendations presented above, the committee concluded that ambient ionization mass spectrometry is a rapidly maturing and highly useful technology with specific available implementations capable of highly sensitive, real-time measurements of relative concentrations of chemical agents adsorbed on a variety of relevant surfaces and in some porous materials. Further, with suitable reference standards, absolute measurements of agent concentrations in ambient air and liquid solutions are feasible. If adopted, these capabilities might be very useful in supplementing the Army's traditional air and vapor headspace agent contamination measurements using current near-real-time agent monitors. A range of scenarios occurring during agent disposal operations and facility closure activities have been defined and developed by the committee to illustrate the potential utility of real-time ambient ionization mass spectrometric detection of chemical agent contamination. Although commercially available ambient ionization mass spectrometry instrumentation in the specific configurations recommended by the committee may not currently be available off the shelf, the major components have been commercialized, and a number of analytical instrument vendors are capable of designing, assembling, and demonstrating instruments meeting potential ACWA specifications. Given the current schedules for anticipated PCAPP and BGCAPP weapons disposal (beginning in 2015 and 2020, respectively) and facility closure activities, it is very likely that these instruments could be specified, tested, and deployed quickly enough to be used at BGCAPP and PCAPP as suggested in this report. In addition, as demonstrated by their work as reviewed in Chapters 4 and 5, Army scientists at the Edgewood Chemical and Biological Center, sited near ACWA headquarters, have significant experience in the application of ambient ionization mass spectrometric measurements of chemical agent concentrations and distributions and could be a resource for developing and testing specific ambient ionization technology implementations for ACWA. Based on these considerations the committee's overarching finding and recommendation are as follows: Finding 6-1. Suitably specified ambient ion mass spectrometry instrumentation could be utilized in a range of challenging activities at ACWA chemical weapons disposal facilities where real-time chemical agent contamination measurements may reduce the time and effort required to characterize chemical agent contamination of waste materials, process equipment, and work areas. Recommendation 6-1. ACWA should carefully evaluate the capabilities of portable ambient ion mass spectrometry and its potential to provide faster and more accurate characterization of chemical agent contamination, as detailed in this report, and determine if these likely benefits justify the effort and investment required to specify, acquire, and deploy suitable implementations of this technology.

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