Hazards And Accident Analyses An Integrated Approach For The Plutonium Facility At Los Alamos National Laboratory

Recently the Final Safety Analysis Report (FSAR) for the Plutonium Facility at Los Alamos National Laboratory, Technical Area 55 (TA-55) was revised and submitted to the US. Department of Energy (DOE). As a part of this effort, over seventy Process Hazards Analyses (PrHAs) were written and/or revised over the six years prior to the FSAR revision. TA-55 is a research, development, and production nuclear facility that primarily supports US. defense and space programs. Nuclear fuels and material research; material recovery, refining and analyses; and the casting, machining and fabrication of plutonium components are some of the activities conducted at TA-35. These operations involve a wide variety of industrial, chemical and nuclear hazards. Operational personnel along with safety analysts work as a team to prepare the PrHA. PrHAs describe the process; identi fy the hazards; and analyze hazards including determining hazard scenarios, their likelihood, and consequences. In addition, the interaction of the process to facility systems, structures and operational specific protective features are part of the PrHA. This information is rolled-up to determine bounding accidents and mitigating systems and structures. Further detailed accident analysis is performed for the bounding accidents and included in the FSAR. The FSAR is part of the Documented Safety Analysis (DSA) that defines the safety envelope for all facility operations in order to protect the worker, the public, and the environment. The DSA is in compliance with the US. Code of Federal Regulations, 10 CFR 830, Nuclear Safety Management and is approved by DOE. The DSA sets forth the bounding conditions necessary for the safe operation for the facility and is essentially a 'license to operate.' Safely of day-to-day operations is based on Hazard Control Plans (HCPs). Hazards are initially identified in the PrI-IA for the specific operation and act as input to the HCP. Specific protective features important to worker safety are incorporated so the worker can readily identify the safety parameters of the their work. System safety tools such as Preliminary Hazard Analysis, What-If Analysis, Hazard and Operability Analysis as well as other techniques as necessary provide the groundwork for both determining bounding conditions for facility safety, operational safety, and day-to-clay worker safety.

A previous report, {open_quotes}Analysis of LANL Options for Processing Plutonium Legacy Materials, {close_quotes} LA-UR-95-4301, summarized the development of a risk-based prioritization methodology for the Los Alamos National Laboratory (LANL) Plutonium Facility at Technical Area-55 (TA-55). The methodology described in that report was developed not only to assist processing personnel in prioritizing the remediation of legacy materials but also to evaluate the risk impacts of schedule modifications and changes. Several key activities were undertaken in the development of that methodology. The most notable was that the risk assessments were based on statistically developed data from sampling containers in the vault and evaluating their condition; the data from the vault sampling programs were used as the basis for risk estimates. Also, the time-dependent behavior of the legacy materials was explicitly modeled and included in the risk analysis. The results indicated that significant reductions in program risk can be achieved by proper prioritization of the materials for processing.

Emergency response at Los Alamos National Laboratory (LANL) is handled through a graded approach depending on the specific emergency situation . LANL maintains a comprehensive capability to respond to events ranging from minor facility events (alerts) through major community events (general emergencies), including criticality accidents . Criticality safety and emergency response apply to all activities involving significant quantities of fissile material at LANL, primarily at Technical Area 18 (TA-18, the Los Alamos Critical Experiments Facility) and Technical Area 55 (TA-55, the Plutonium Facility). This discussion focuses on response to a criticality accident at TA-55; the approach at TA-18 is comparable.

The conceptual design of an on-line, near-real-time nondestructive assay instrumentation network for the Los Alamos Plutonium Facility is complete. Analysis of instrument history data indicates that the instrument certification procedures need improvement. Analysis of exhaust filter data has led to the derivation of a buildup prediction equation that is a function of throughput. This suggests that development of a generalized model is possible. A number of routine reports are now available from the Plutonium Facility/Los Alamos Safeguards System including inventories and active reports.

" Plutonium-a man-made element produced by irradiating uranium in nuclear reactors-is vital to the nuclear weapons stockpile. Much of the nation's current plutonium research capabilities are housed in aging facilities at Los Alamos National Laboratory in New Mexico. These facilities pose safety hazards. The National Nuclear Security Administration (NNSA) has decided to construct a multibillion dollar Chemistry and Metallurgy Research Replacement Nuclear Facility (CMRR) to modernize the laboratory's capabilities to analyze and store plutonium. GAO was asked to examine (1) the cost and schedule estimates to construct CMRR and the extent to which its most recent estimates reflect best practices, (2) options NNSA considered to ensure that needed plutonium research activities could continue, and (3) the extent to which NNSA's plans reflected changes in stockpile requirements and other plutonium research needs. GAO reviewed NNSA and contractor project design documents and visited Los Alamos and another plutonium facility at Lawrence Livermore National Laboratory in California. "