Three Mile Island:

The Most Studied Nuclear Accident in History

EMD-80-109: Published: Sep 9, 1980. Publicly Released: Sep 9, 1980.

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GAO reviewed eight investigative reports and other supporting material on the nuclear accident at Three Mile Island. Most investigators agreed that the accident was caused by a combination of factors, including equipment malfunctions, inadequate operator training, poor designs, and inadequate operating and emergency procedures. Many of these deficiencies had been known by the Nuclear Regulatory Commission (NRC) for some time, but most were not considered important in view of NRC strategy for reactor licensing and design. The practices, procedures, and attitudes of NRC were challenged to such an extent that a major reorganization and restructuring of the agency was recommended. Previous GAO reports identified many of the same problems as found by the Three Mile Island investigations. Several of the studies of the radiation doses received by the population around Three Mile Island and by plant workers concluded that the accident had a negligible effect on the physical health of these people; however, it had a demoralizing effect on them.

The investigations varied in depth and comprehensiveness, but were generally consistent. GAO endorses the President's reorganization plan, which would greatly expand the management role and authority of the Chairman but leave the Commissioners responsible for setting policy and providing the operational framework. NRC has taken or planned action on the recommendations, which included establishing safety goals, making powerplant standardization mandatory, improving the role of the Advisory Committee on Reactor Safeguards, and providing funding and legal counsel to public groups or individuals intervening in licensing proceedings. However, little progress has been made on establishing goals and criteria which describe what level of safety and nuclear regulation is enough. GAO endorses a provision in the 1981 authorizing legislation which directs NRC to develop a proposed safety goal for nuclear reactor regulation. NRC needs to develop some systematic way to increase its participation in important licensing and regulatory decisions. GAO favors options that increase the Commissioners' role in the licensing and adjudication process, while retaining the Atomic Safety and Licensing Appeal Board and its basic agency responsibilities. NRC has not completed long-term and important actions to improve specific design and operating problems. GAO endorses the proposed creation of a special Nuclear Safety Oversight Committee and believes that NRC should submit annual reports to Congress on its progress in implementing action plans.

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Apr 29, 2020

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    Priority Open Recommendations:

    Department of Energy
    GAO-20-285PR: Published: Apr 22, 2020. Publicly Released: Apr 29, 2020.

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Feb 26, 2020

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    Science & Tech Spotlight:

    Nuclear Microreactors
    GAO-20-380SP: Published: Feb 26, 2020. Publicly Released: Feb 26, 2020.

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