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Type B Accident Investigation of the Americium Contamination Accident

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Type B Accident Investigation of the Americium Contamination Accident UNITED STATES DEPARTMENT OF ENERGY NATIONAL NUCLEAR SECURITY ADMINISTRATION Table of Contents Prologue ................................................................................................................................................ iii Executive Summary ................................................................................................................................v 1.0 Introduction ...................................................................................................................................... 1 1.1 Background .......................................................................................................................................................... 1 1.2 Facility Description ............................................................................................................................................. 1 1.3 Organizational Descriptions ............................................................................................................................. 2 1.4 Scope, Purpose, and Methodology ................................................................................................................. 4 2.0 Discussion of the Accident ..............................................................................................................7 2.1 Room R3 in the Sigma Facility ......................................................................................................................... 7 2.2 Rooms 126, 127, and 128 in PF-4 .................................................................................................................... 8 2.3 The Event............................................................................................................................................................. 8 2.4 Pre-Discovery Activities .................................................................................................................................. 10 2.5 Discovery............................................................................................................................................................ 11 2.6 Onsite LANL Response .................................................................................................................................. 11 2.7 Offsite LANL/RAP Response ....................................................................................................................... 17 2.8 Consequences .................................................................................................................................................... 19 2.8.1 Impacts to Personnel ............................................................................................................................. 19 2.8.2 Impacts to Facility Operations ............................................................................................................. 19 2.9 Accident Reconstruction ................................................................................................................................. 20 3.0 Accident Facts and Analysis ........................................................................................................... 31 3.1 LANL’s Implementation of ISM ................................................................................................................... 32 3.1.1 Core Function 1: Define the Scope of Work .................................................................................... 32 3.1.2 Core Function 2: Analyze the Hazards ............................................................................................... 34 3.1.3 Core Function 3: Develop and Implement Controls ....................................................................... 36 3.1.4 Core Function 4: Perform Work Within Controls ........................................................................... 38 3.1.5 Core Function 5: Feedback and Improvement ................................................................................. 39 3.1.6 Guiding Principle 2: Clear Roles and Responsibilities ..................................................................... 40 3.1.7 Guiding Principle 3: Competence Commensurate with Responsibilities ..................................... 40 3.2 LANL’s Response to Onsite Contamination ............................................................................................... 41 3.3 NNSA and LANL’s Response to Offsite Contamination.......................................................................... 43 3.4 LANL’s Radiation Protection Program......................................................................................................... 47 3.5 LANL’s Material Control and Accountability Program ............................................................................. 49 3.6 LANL’s Radioactive Materials Transportation Program ............................................................................ 51 3.7 Formality of Operations.................................................................................................................................. 52 3.8 LANL’s Feedback and Improvement Programs .......................................................................................... 56 3.9 NNSA Oversight Programs ............................................................................................................................ 59 3.10Events and Causal Factors, Barriers, and Change Analyses....................................................................... 63 4.0 Conclusion, Causes, and Judgments of Need ............................................................................... 65 5.0 Board Signatures............................................................................................................................. 75 6.0 Board Members, Advisors, and Staff.............................................................................................. 77 Appendix A: Board Letter of Appointment......................................................................................... 79 Appendix B: Events and Causal Factors Chart ................................................................................... 81 Appendix C: Barrier Chart ................................................................................................................... 93 Appendix D: Change Chart ................................................................................................................. 97 Acronyms ................................................................................................................................Back Cover TYPE B INVESTIGATION OF THE AMERICIUM-241 CONTAMINATION AT THE SIGMA FACILITY, LOS ALAMOS NATIONAL LABORATORY On August 15, 2005, I appointed a Type B Accident Investigation Board to investigate the July 14, 2005 Americium-241 contamination accident at the Sigma Facility of Los Alamos National Laboratory, in Los Alamos, New Mexico. The Board’s responsibilities have been completed with respect to this investigation. The analysis, identification of contributing and root causes, and judgments of need reached during the investigation were performed in accordance with DOE Order 225.1A, Accident Investigations. I accept the report of the Board and authorize release of this report for general distribution. __________________________________ __________________________ Edwin L. Wilmot Date Manager, Los Alamos Site Office National Nuclear Security Administration This report is an independent product of the Type B Accident Investigation Board appointed by Edwin L. Wilmot, Manager of the Los Alamos Site Office of the National Nuclear Security Administration, U.S. Department of Energy. The Board was appointed to perform a Type B investigation of this accident and to prepare an investigation report in accordance with DOE Order 225.1A, Accident Investigations. The discussion of facts, as determined by the Board, and the views expressed in the report do not assume and are not intended to establish the existence of any duty at law on the part of the U.S. Government, its employees or agents, contractors, their employees or agents, or subcontractors at any tier, or any other party. This report neither determines nor implies liability. i UNITED STATES DEPARTMENT OF ENERGY NATIONAL NUCLEAR SECURITY ADMINISTRATION ii TYPE B INVESTIGATION OF THE AMERICIUM-241 CONTAMINATION AT THE SIGMA FACILITY, LOS ALAMOS NATIONAL LABORATORY Prologue Interpretation of Significance On July 14, 2005, a worker at the Los Alamos National Laboratory received and opened a shipment of radioactive material from another facility in the Laboratory. The material had been inadvertently contaminated during its preparation in a glovebox. The material was not evaluated for radiological contamination before being shipped, even though it was known that there was a good possibility for contamination. The shippers assumed that the receiver knew there was a potential for contamination and would act accordingly. The receiver assumed that the material was not contaminated because he had not been told otherwise. The contamination was not discovered for eleven days. In the interim, the contaminant was spread through the receiving facility, the worker’s home, two of his relatives’ homes, and the homes or vehicles of two other workers. An extensive effort, with activities in four states, was necessary to respond to this accident. However, the situation could have been much worse, given
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