Three Mile Island Accident of 1979 Knowledge Management Digest – Overview (NUREG/KM-0001, Revision 1)

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Publication Information

Date Published: June 2016

Division of Risk Analysis
Office of Nuclear Regulatory Research
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

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Although it caused no deaths or injuries, the accident at the Three Mile Island, Unit 2 (TMI-2) nuclear power plant was the most serious incident in U.S. commercial nuclear power history. The accident began in the early morning hours of March 28, 1979, at the newly-licensed power plant near Middletown, Pennsylvania, and its effects on nuclear safety and regulation continue to this day. Three Mile Island spurred the U.S. Nuclear Regulatory Commission (NRC) to tighten and heighten its regulatory oversight of the nuclear power industry to ensure the safety of the public and the environment. Investigations and the implementation of lessons learned brought about sweeping changes in the U.S. nuclear industry. These included improvements in emergency response planning, reactor operator training, human factors engineering, radiation protection, and many other areas of nuclear power plant operations and design. The NRC and the U.S. Department of Energy (DOE) have intensively studied and documented the TMI-2 accident.

This multimedia digest was the first in the NRC’s NUREG knowledge management (NUREG/KM) series. One of the missions for NUREG/KMs is to preserve knowledge for future generations of the important historical events and research that have shaped the NRC’s regulatory programs. This knowledge management digest and supporting DVD contain the most important documents that the NRC, the licensee, and other government organizations issued following investigations and cleanup of the accident. Although a few key documents have become available electronically, this NUREG/KM marks the first time that the NRC has digitized these historically important documents. On the DVD, the table of contents on the welcome page provides access to these reports.

About Revision 1.  This revision of NUREG/KM-0001 has evolved into two volumes. This volume presents overviews of the accident: emergency response, investigations, regulatory implications, and accident recovery. This volume includes topics and documents provided on the original DVD with new ones added. Supplement 1 expounds upon the technical details of recovery and cleanup activities: management and oversight, plant stabilization, worker protection, data acquisition and analysis, waste management, decontamination, defueling, and after defueling. The document collections in this supplement are derived from correspondence between the utility and NRC, and from the results of research activities. The accompanying DVDs for both volumes contain about 4,000 documents.

In addition to the large collection of documents, this volume provides three NRC multimedia presentations, "The Accident at Three Mile Island, A Look Back: Preserving the Institutional Memory after 30 Years," "The 35th Anniversary of the Three Mile Island Nuclear Power Plant Accident of 1979: Working at TMI During and Following the Accident," and "Moments in NRC History, Three Mile Island, March 28, 1979."

This NUREG/KM does not fully convey the complete NRC experience in the aftermath of the accident. Other interesting topics for future studies of the TMI-2 accident include: legal lawsuits and actions; court proceedings, including those at the U.S. Supreme Court; Atomic Safety and Licensing Board proceedings; enforcement actions; the utility’s financial crisis; interactions with Congress; interactions with Federal, State, and local government agencies; public outreach; the TMI Unit 1 restart; and oversight by the NRC’s Advisory Committee for Reactor Safeguards (ACRS).

How to Use this Digest.  A few suggestions for navigating through this NUREG/KM, and the many documents on the DVD, are provided at the end of this NUREG/KM (see the section on DVD Navigation and Interpretation). The historical documents provided on the DVD are for reference only, and are not official NRC records.

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