ML19322A266
| ML19322A266 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 02/12/1979 |
| From: | Reid R Office of Nuclear Reactor Regulation |
| To: | Herbein J METROPOLITAN EDISON CO. |
| References | |
| NUDOCS 7903140535 | |
| Download: ML19322A266 (3) | |
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'g UNITED STATES g.y NUCLEAR REGULATORY COMMisslON f. k/. [ ;j WASHINGTON, D. C. 20555
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February 12, 1979
-s Docket No. 50-289 Mr. J. G. Herbein Vice President Metropolitan Edison Company P. O. Box 542 Reading, Pennsylvania 19640
Dear Mr. Herbein:
By letter dated September 14, 1977 we requested that you provide for Three Mile Island Nuclear Station, Unit No.1 (TMI-1) an analysis of the potential for and consequences of boron dilution accidents at your facility.
We further stated that the analysis should be based upon conservative assumptions consistent with the design of TMI-l and the TMI-l Technical Specifications, and should include the as,sumption of the most limiting single failure.
We-also requested that the analysis include an assessment of the factors which affect the capability of the operator to take corrective action which would teminate the postulated events prior to attaining reactor criticality.
We have reviewed your submittal of December 16, 1977 and conclude that, you have not been fully responsive to our request.
Specific deficiencies we have noted include the following:
1.
You have not provided an analysis of the Na0H moderator dilution accident for the specific plant configuration at TMI-1. The statement in your submittal to the effect that consideration of such an accident is not needed for TMI-l because it would require more than a single failure, is not considered valid unless there are no conditions when surveillance is performed on NaOH valves while the Decay Heat Removal System (DHRS) is open to the Reactor Coolant System (RCS).
If there are any such conditions, only a single failure need be postulated to pemit the NaOH moderator dilution accident.
Accordingly, you should either: (1) certify that there are no conditions where Na0H valves are tested while the DHRS is open to the RCS, l
or (2) provide a conservative analysis
- of the Na0H mod-l As defined in our letter of September la,1977.
l 7 9 0 314 0'53T l
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Metropolitan Edison Company erator dilution accident for the specific conditions applicable to TMI-1 and an a::sessnent of the capability of the operator to respond to this event.
If you elect to follow this second alternative you should also propose any corrective action deemed necessary to prevent or mitigate the consequences of such an event.
2.
You did not provide, as requested, an analysis of the potential for and consequences of other methods for initiating a moderator dilution event.
In partial fulfillment of this request you did reference several moderator dilution events considered in the FSAR.
You did not, however, indicate whether you had performed a comprehensive analysis to determine if there were mechanisms other than those considered in the FSAR.
Accordingly, you should perform such an analysis to identify any other mechanisms and the consequences thereof.
If such additional mechanisms are identified which are not bounded by those considered in the FSAR, you should identify the mechanisms, provide your eval-uation and propose corrective action to prevent or mitigate the consequences of such events.
It is requested that the additional information identified above be submitted within 60 days of receipt of this letter.
Sincerely, a./h'];f 47 obert W. Raid, Chief Operating Reactors Branch !4 Division of Operating Reactors cc: See next page
i i
!!etropolitan Edison Company cc:
G. F. Trowbridge, Esquire Shaw, Pittman, Potts & Trowbridge 1800 f t Street, N.W.
Washington, D.C.
20036 GPU Service Corporation Richard W. Heward, Project manager Mr. E. G. Wallace, Licensing Manager 260 Cherry Hill Road Parsippany, New Jersey 07054 Pennsylvania Electric Company Mr. R. W. Conrad Vice President, Generation 1001 Broad Street Johnstown, Pennsylvania 15907 tiiss itary V. Southard, Chairman Citizens for a Safe Environment P. O. Box 405 Harrisburg, Pe,nnsylvania 17108 Mr. Robert B. Borsum Babcock & Wilcox Nuclear Pcwer Generation Division-Suite 420, 7735 Old Georgetown Road Bethesda, Maryland 20014 Government Publications Section State Library of Pennsylvania Box 1601 (Education Building)
Harrisburg, Pennsylvania 17126 t
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