• Providing the basis for segregating contaminated from noncontaminated materials into segregated waste streams. This issue occurs during process operations but may be more pressing during the facility deconstruction. As noted above, challenges include the possible presence of hidden or occluded contamination that might escape easy detection using vapor monitoring but may be exposed during demolition, collection, and transport of the materials in question. Issues may include the need to screen large amounts of material quickly enough to enable efficient processing into segregated streams on an ongoing, real-time basis and the challenge of efficiently scanning for localized hot spots, where lack of contamination of specific samples may not be sufficient to rule out contamination of the aggregate. Fast and effective detection of agent-contaminated surfaces may provide additional protection to demolition workers against acute releases of hidden reservoirs of material and identify structures that need special care in their demolition.
There are several potential advantages of the new analytical approaches. First, the ability to identify the source of contamination in a complex matrix of potential sources can lead to more efficient detection of residual contamination by agent trapped in occluded spaces. Second, the ability to simultaneously evaluate multiple potential contaminants may also be an advantage of the new measurement capabilities. Third, the ability to detect a source by following an airborne agent concentration gradient with a real-time measurement can lead to more rapid and efficent identification of an agent vapor source and decrease the extent of residual contamination. Fourth, waste streams such as spent activated carbon that are not amenable to analysis of headspace vapors can be interrogated in real time using these new methods.
However, in order to realize the potential benefits listed above, it must first be determined that these new methods have sufficient precision and accuracy to support the required, real-time, low-level-of-agent detection and quantitation in routine practice. What is the sensitivity and specificity of these new methods relative to existing procedures? To what extent can significant residual contamination be identified by these new methods that may not be detectable using existing methods such as headspace vapor analyses? How often can the rapid, in situ capabilities offered by the new methods be used to significantly reduce the time and effort required for necessary routine maintenance, upset response, agent changeover, or closure deconstruction procedures?
In reviewing the Assembled Chemical Weapons Alternatives (ACWA) documents, there is little detailed description of the statistical methodologies guiding current agent monitoring and measurement methods. Most available material is presented in the ACWA document Chemical Agent Laboratory and Monitoring Quality Assurance Plan (LMQAP) (U.S. Army, 2011b). On page 7 of the plan, the authors state the objective: