lower-level exposure have been met. The instruments and methods used for these purposes were reviewed in earlier National Research Council (NRC) reports (e.g., NRC, 2005a) and are not the subject of this report. Proactive evaluations of potential agent vapor sources that might lead to contaminated air (e.g., identifying potential agent vapor sources during maintenance or deconstruction activities) are a second element that may be aided by the new technologies discussed in Chapter 4.
• Contamination of local ambient air. During operations, the heating, ventilation, and air conditioning (HVAC) outflow is monitored with traditional methods for measuring airborne agents. During deconstruction, the containment and processing of the workplace air will no longer be in operation, and fugitive agent emissions from the site resulting from off- gassing from no-longer-contained contaminated materials may be an issue. Current airborne monitoring methods can detect any significant agent vapor concentrations. However, new surface analysis technologies may be useful in directing efficient decontamination activities, thus reducing the possibility of airborne agent contamination.
• Monitoring waste streams. During operations, agent monitoring can verify that procedures for preventing contamination are effective or assure that decontamination of any agent in or on protective gear and other waste streams are adequate. Waste streams of interest include used protective equipment, processed shell and rocket casings and other packaging materials, and the output of the chemical destruction process itself. Agent monitoring goals include assuring that workers handling waste streams are not subject to acute risks from contaminated material that has uncharacteristically and unintentionally entered the waste stream; assuring that any low-level contamination of the stream does not pose a hazard to workers from long- term, low-level exposure; assuring that any fugitive emissions during transport and disposal of wastes are not of concern; and evaluating the long-term safety of the ultimate disposal and storage methods. It may be important to characterize the mass of agent being exported with a waste stream, even at very low concentrations.
• Detecting and characterizing incidents of accidental contamination or failure of containment. The aim is to detect agent contamination before it can spread and be redistributed or cross-contaminate a wider area or commingled material. For such incidents, measuring the degree of contamination and delimiting its spread and extent will be key to efficient handling of contaminated material. Proactive investigation of the amount of spread and redistribution of local contamination from even well-performing routine operations may be wise. Materials that may absorb or trap ambient air agent vapors (such as electrical insulation) may be worth assessing.