ML20137W750
| ML20137W750 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 12/03/1985 |
| From: | Charemagne Grimes Office of Nuclear Reactor Regulation |
| To: | Opeka J NORTHEAST NUCLEAR ENERGY CO. |
| References | |
| NUDOCS 8512100331 | |
| Download: ML20137W750 (3) | |
Text
P
- F UNITED STATES 8
N NUCLEAR REGULATORY COMMISSION
- l WASHINGTON,0. C. 20555 December 3,1985 Docket No.:
50-245 Mr. John F. Opeka, Senior Vice President Nuclear Engineering and Operations Nor.heast Nuclear Engineering Company Post. Office Box 270 Hart ford, Connecticut 06141-0270
Dear Mr. Opeka:
SUBJECT:
CONTINU0US CONTAINMENT LEAK RATE MONITORING Re: Millstone Nuclear Power Station, tinit No. 1 In a letter dated November 20, 1985, you informed the staff that the containment connections for the containment " pump back" system (for drywell-wetwell differential pressure) and continuous containment leakage mwitoring would not be completed during the 1985 refueling outage as described in your March 19, 1985 letter.
Instead, you proposed that these modifications will be completed during the 1987 refueling outage (Sumner 1987).
In this manner, the containment test required by Appendix J to 10 CFR 50 following the installation of the associated containment penetrations would be satisfied by the containment Integrated Leal Rate Test (ILRT) coincident with the ten-year Inservice inspection Protram during the 1987 outage.
Your letter also noted that you have undertaken a study regarding the possibility of eliminating the need for a drywell-wetwell pressure differential and, therefore, the need for the " pump back" connections.
In this regard, we note that the pressure differential between the drydell and wetwell provides assurance that all ten 18-inch drywell vacuum breakers are properly seated so as to minimize steam bypass of the suppression pool during design basis accidents. Moreover, the elimination of the drywell-wetwell differential pressure will involve a reevaluation of the SRV and LOCA hydrodynamic loads on the torus (wetwell).
In the interim, the drywell-wetwell differential pressure and containment inerting otherwise required in the plant Technical Specifications provide a gross measure of containment leakage integrity over and above the testing requirements in 10 CFR 50 Appendix J.
Consequently, the staff concludes that your proposal to postpone these modifications is acceptable. Alternative means to resolve this issue will be considered in Topic 1.14 of the Integrated Safety Assessment Program, a912100331 851203 DR ADOCK 0000 5
December 3,1985
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4 Mr. John F. Opeka The results of your evaluation and any proposed-plant modifications should be submitted for staff review at least 90 days before the next refueling outage.
Original signed by:
C. Grimes Christopher I. Grimes, Di>ector Integrated Safety Assessment Project Directorate Division of PWR Licensing - B cc: See Next Page DISTRIBUTION C~~iN7 ISAPD Reading NRC POR Local PDR FMiraglia OELD EJordan BGrimes JPartlow JShea PAnderson ACRS (10)
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s f-Mr. John F. Opeka Millstone Nuclear Power Station Northeast Nuclear Energy Company Unit No. I cc:
Gerald Garfield, Esquire Kevin McCarthy, Director Day, Berry & Howard Radiation Control Unit Counselors at Law Department of Environmental City Place Protection Hartford, Connecticut 06103-3499 State Office Building Hartford, Connecticut 06106 Edward J. Mroczka Vice President, Nuclear Operations
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Northeast Utilities Service Company Post Office Box 270 Hartford, Connecticut 06141-0270 State of Connecticut Office of Policy and Management ATTN: Under Secretary Energy Division 80 Washington Street Hartford, Connecticut 06106 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, Pennsylvania 19406 Northeast Nuclear Energy Company ATTN: Superintendent Millstone Nuclear Power Station P. O. Box 128 Waterford, Connecticut 06385 Resident Inspector c/o U.S. NRC Millstone NucIear Power Station P. O. Box 811 Niantic, Connecticut 06357 First Selectman of the Town of Waterford Hall of Records 200 Boston Post Road Waterford, Connecticut 06385
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