Section 1 IntroductionIn June of 1987, the Haste Management Project Office (WMPO) of the Department of Energy conducted a special audit of the activities of the Nevada Nuclear Waste Storage Investigation (NNWSI) Project at Liverrnore. Observation No. 1 of the audit report (WMPO Audit S-87-1) stated that "The rationale for use of Well 3-13 water as the basis for the reference criteria for NNWSI Project activity (until water samples from the unsaturated zone are available) is not clear." A brief reply to that observation was given by the NNWSI Project staff, citing discussions of the justification for using J-I3 water in the Yucca Mountain Environmental Assessment Report Q), which in turn outlines some of the relevant literature on this point. However, it has been noted that there never has been a comprehensive, well-documented examination of the basis for the use of J-13 water in the nuclear waste storage investigations.The management of the NNWSI Project at Livermore therefore asked that a committee be formed to review more thoroughly the question of the validity of the use of J-13 water as a reference material. This committee was composed of scientists who had expertise in the requisite technical areas, but who were not involved in the current activities of the NNWSI Project. The committee was also charged with reexamining and recommending, in the light of the assessment of the technical validity of the use of J-13 water, the NNWSI quality-assurance level to which future activities involving J-13 water should be assigned. This document is a report of these findings.It was apparent to the committee from the outset that the overall question of the rationale for use of J-13 water extends beyond just the Livermore studies, which mostly have dealt with phenomena in the so-called "near-field" region of the repository, which is the region that will be influenced by heat from the radioactive waste. Thus far, the Livermore work has focussed mostly on experimental and computer-modeling studies of rock/water, metal-alloy/water, and waste-form/water interactions. Other investigators, particularly at Los Alamos National Laboratory, have been concerned with the behavior, e. g., transport, of radionuclides in the ground waters outside the immediate Yucca Mountain area of the repository site. Thus the question of the validity of J-13 water as a reference material i f a more global one, and should be asked -1.1-in terms of the NNWSI program as a whole, and not just with respect to waters in the unsaturated zone as was done by the WMPO audit committee. In this sense, we may have enlarged the scope of the enquiry somewhat, but we believe it has led to a more coherent, if not more satisfying answer. Water from the J-13 well has been used experimentally in waste storage studies for at least ten years. Beginning in about 1977 (2) at Los Alamos, the ready availability of 0-13 water and its known similarity to the other Nevada Test Site ground waters made it a natural choice as a surrogate water for experiments designed to measure phe...
Increasingly sophisticated technologies are needed for counterterrorism responses to biological and chemical warfare agents. Recently developed detection and identification systems are characterized by increased sensitivity, greater automation, and fewer false alarms. Attempts are also under way to reduce the cost and complexity of field-deployable systems. A broad range of decontamination reagents for equipment and personnel is emerging, but decontamination of large buildings, inaccessible spaces, and sensitive equipment remains problematic.
In the event of a biothreat agent release, hundreds of samples would need to be rapidly processed to characterize the extent of contamination and determine the efficacy of remediation activities. Current biological agent identification and viability determination methods are both labor-and time-intensive such that turnaround time for confirmed results is typically several days. In order to alleviate this issue, automated, high-throughput sample processing methods were developed in which real-time PCR analysis is conducted on samples before and after incubation. The method, referred to as rapid-viability (RV)-PCR, uses the change in cycle threshold after incubation to detect the presence of live organisms. In this article, we report a novel RV-PCR method for detection of live, virulent Bacillus anthracis, in which the incubation time was reduced from 14 h to 9 h, bringing the total turnaround time for results below 15 h. The method incorporates a magnetic bead-based DNA extraction and purification step prior to PCR analysis, as well as specific real-time PCR assays for the B. anthracis chromosome and pXO1 and pXO2 plasmids. A single laboratory verification of the optimized method applied to the detection of virulent B. anthracis in environmental samples was conducted and showed a detection level of 10 to 99 CFU/sample with both manual and automated RV-PCR methods in the presence of various challenges. Experiments exploring the relationship between the incubation time and the limit of detection suggest that the method could be further shortened by an additional 2 to 3 h for relatively clean samples.If a biothreat agent was released, hundreds to thousands of environmental samples of diverse types would need to be rapidly processed and analyzed in order to first characterize the contamination of the site and then assess the effectiveness of decontamination activities. Decision-makers also need rapid results for remobilizing disinfection equipment in the case of incomplete decontamination and for reopening facilities and areas based on results from clearance sampling (12)(13)(14).Current methods used by the Centers for Disease Control and Prevention (CDC) to assess the viability of spores on surfaces rely on culturing samples on solid media (5, 6). These methods involve several manual steps, including pipetting to prepare dilution series, plating of numerous replicates for a series of dilutions, and colony counting, which make it labor-, space-, and time-intensive. Typically, only 30 to 40 samples may be processed each day with confirmed results obtained days later (5, 6). Validated rapid-viability test protocols are therefore needed to ensure public safety and to help mitigate impacts due to facility closures following a biothreat agent release. This critical need was highlighted during the response to the 2001 anthrax attacks, in which clearance sampling and analysis required excessive time prior to facilities reopening.Because risk assessment after such an attack is determined on the basis of the presence of viabl...
The objective of this assessment is to determine what level of cleanup will be required to meet regulatory and stakeholder needs in the case of a chemical and/or biological incident at a civilian facility. A literature review for selected, potential chemical and biological warfare agents shows that dose information is often lacking or controversial. Environmental regulatory limits or other industrial health guidelines that could be used to help establish cleanup concentration levels for such agents are generally unavailable or not applicable for a public setting. Although dose information, cleanup criteria, and decontamination protocols all present challenges to effective planning, several decontamination approaches are available. Such approaches should be combined with risk-informed decision making to establish reasonable cleanup goals for protecting health, property, and resources. Key issues during a risk assessment are to determine exactly what constitutes a safety hazard and whether decontamination is necessary or not for a particular scenario. An important conclusion is that cleanup criteria are site dependent and stakeholder specific. The results of a modeling exercise for two outdoor scenarios are presented to reinforce this conclusion. Public perception of risk to health, public acceptance of recommendations based on scientific criteria, political support, time constraints, and economic concerns must all be addressed in the context of a specific scenario to yield effective and acceptable decontamination.
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