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Nuclear Regulatory Commission: Oversight of Underground Piping Systems Commensurate with Risk, but Proactive Measures Could Help Address Future Leaks

GAO-11-563 Published: Jun 03, 2011. Publicly Released: Jun 21, 2011.
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All U.S. nuclear power plant sites have had some groundwater contamination from radioactive leaks, and some of these leaks came from underground piping systems. The Nuclear Regulatory Commission (NRC) regulates nuclear power plants to protect public health and the environment from radiation hazards. GAO was asked to (1) determine experts' opinions on the impacts, if any, of underground piping system leaks on public health and the environment; (2) assess NRC requirements of licensees for inspecting these systems and monitoring and reporting on leaks; (3) identify actions the nuclear power industry, licensees, and NRC have taken in response to leaks; and (4) identify additional NRC requirements, if any, that key stakeholders think could help prevent, detect, and disclose leaks. GAO convened expert discussion groups through the National Academy of Sciences and asked experts to review three case studies, analyzed documents, visited seven plant sites and two NRC regional offices, and interviewed stakeholders.

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Recommendations for Executive Action

Agency Affected Recommendation Status
Nuclear Regulatory Commission To ensure the continued protection of the public's health and safety, the Chairman of NRC should direct agency staff to periodically evaluate the extent to which the industry's voluntary Groundwater Protection Initiative will result in prompt detection of leaks and, based upon these evaluations, determine whether the agency should expand its groundwater monitoring requirements.
Closed – Implemented
NRC has performed inspections to assess the groundwater protection programs of nuclear power plant licensees and has reviewed options to potentially revise the overall regulatory approach to groundwater protection. Specifically, in 2011, NRC performed inspections across all 65 nuclear power plant sites to determine whether licensees had implemented, through the industry Groundwater Protection Initiative, the necessary procedures and processes to respond to a leak or spill of radioactive material to groundwater. Later that year, NRC initiated follow-up inspections across the plant sites to determine whether licensees implemented the elements of their groundwater protection programs identified as incomplete in the original inspection. In addition, in 2012 based in part on our findings reported in GAO-11-563, NRC analyzed two options for the overall regulatory approach to groundwater protection: (1) continue the current regulatory approach, which includes regulatory requirements issued in a June 2011 final rule on decommissioning planning that requires licensees to perform soil and groundwater surveys to identify residual radioactive contamination, as well as continued inspections to monitor the effectiveness of industry initiatives; and (2) propose new rulemaking, which would require an analysis demonstrating that the cost to implement any new regulations would be justified by an increase the regulations would provide in overall protection of public health and safety. On May 24, 2012, the Commission voted to continue the current regulatory approach. We consider these actions sufficient to fulfill the intent of our recommendation.
Nuclear Regulatory Commission To ensure the continued protection of the public's health and safety, the Chairman of NRC should direct agency staff to stay abreast of ongoing industry research to develop technologies for structural integrity tests and, when they become feasible, analyze costs to licensees of implementing these tests compared with the likely benefits to public health and safety. Based on this analysis, NRC should determine whether it should expand licensees' inspection requirements to include structural integrity tests for safety-related underground piping.
Closed – Implemented
NRC has actively stayed abreast of industry research on strutural integrity testing technology through meetings with industry. As of March 2012, NRC had determined that the inspection technology was not yet sufficiently mature for routine application in nuclear power plant facilities, but in response to our recommendation, included a milestone in its November 2011 Buried Piping Action Plan to stay abreast of industry research and, when technology is feasible, analyze the costs and benefits of such tests. We consider these actions to fulfill our recommendation.

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Environmental monitoringGroundwaterGroundwater contaminationHealth hazardsIndustrial facilitiesInformation disclosureInspectionLicensesNuclear powerplant safetyNuclear powerplantsNuclear radiation monitoringPublic healthRadiation exposure hazardsRadiation safetyRadioactive materialsReporting requirementsRadiation detection