NRC Generic Letter 80-18, Crystal River 3 Reactor Trip From Approximately 100% Full Power

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GL80018

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555

March 6, 1980 TO ALL OPERATING B&W REACTOR LICENSEES

As you know, on February 26, 1980, the Crystal River Unit No. 3 Nuclear Station (CR-3) experienced a reactor trip from approximately 100% full power. The initiating event was a failure in the power supplies for the non-nuclear instrumentation. As discussion of the event was presented by the Florida Power Corporation (FPC) in a meeting attended by representatives of your company in Bethesda, Maryland, on March 4, 1980. FPC also discussed the planned corrective action that would be taken at CR-3. The sequence of events presented by FPC and the planned corrective actions at CR-3 are attached to this letter as Enclosures 1 and 2 respectively.

Representatives from all other B&W operating plants were also present at the March 4, 1980 meeting. Each licensee addressed the history of non-nuclear instrumentation problems at his facility, the susceptibility of his plant(s)

to the CR-3 event, and any corrective action that has been, or will be, taken.

On a related matter, Office of Inspection and Enforcement Bulletin 79-27 was issued subsequent to a similar event at the Oconee Nuclear Station, Unit No. 3, on November 10, 1979. This bulletin requested your review of certain matters relative to the Oconee event, and its implication on the operation of your facility, does not relieve you of your responsibilities to provide the information requested by IE Bulletin 79-27.

Because of the implications of the CR-3 event, and potential adverse effects on the public health and safety that could result from future events of this type, we believe that certain information in addition to that requested in IE Bulletin 79-27, should be promptly provided to the NRC concerning your facility. In accordance with 10 CFR 50.54 (f), you are requested to provide us with information in response to Items 1 through 5 of Enclosure 3, submitted under oath or affirmation, no later than close of business March 12, 1980. Information in response to Items 6 and 7 of Enclosure 3 should be submitted no later than close of business March 17, 1980. The information provided in your responses will enable us to determine whether or not your license should be notified, suspended, or revoked.

This letter confirms the oral request for this information expressed at the March 4, 1980 meeting by Mr. Darrell G. Eisenhut, Acting Director, Division of Operating Reactors.

Harold R. Denton, Director Office of Nuclear Reactor Regulation Enclosures: As stated

.

Enclosure 3

Information requested by COB, March 12 and March 17, 1980

1. Summarize power upset events on NNI/ICS that have previously occurred at your plant.

2. Specifically review the Crystal River event, and address your plant's susceptibility to it in general.

3. Set forth the information presented by your representative(s) in the meeting on March4, 1980.

4. Address information available to the operator following various NNI/ICS power upset events, including a discussion of:

- how the operator determines which information is reliable

- what information is needed to bring the plant to cold shutdown

5. Address the feasibilty of performing a test to verify reliable information that remains following various NNI/ICS power upsets.

6. Address each CR-3 proposed corrective action in terms of applicability to your plant.

7. Expand your review under IE Bulletin 79-27 to include the implications of the CR-3 event. Inform us of your schedule for completion of this expanded review as discussed on March 4, 1980.

In addition to the above, Florida Power Corporation should address:

1. Sequence of events for the CR-3 trip

2. Proposed corrective actions at CR-3

3. Discuss the impact, whether it be beneficial or detrimental, of NRC Short Term Lessons Learned and Bulletins and Orders requirements.