ML19338E993
| ML19338E993 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 09/24/1980 |
| From: | Ippolito T Office of Nuclear Reactor Regulation |
| To: | Rich Smith VERMONT YANKEE NUCLEAR POWER CORP. |
| References | |
| NUDOCS 8010070263 | |
| Download: ML19338E993 (4) | |
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SEPTEMBER 2 4 1980 Docket No. 50-271 Mr. Robert L. Smith Licensing Engineer Vermont Yankee Nuclear Power Corporation 25 Research Drive Westboro, Massachusetts' 01581
Dear Mr. Smith:
By our letter dated August 7,1978, we informed you of deficiencies we identified in the design of the Hatch 2 regulator system for the rotor generator (M-G) sets which supply power to the reactor protection system (RPS).
In general, the problem involved the possibility of the M-G producing power which was of a quality (High/ low outage, etc.)
that could be outside that for which the RPS has been demonstrated to be acceptable.
Specifically, the deficiencies involved:
(1) Potential sequence of undetected single component failures which could adversely affect the operability of the RPS; and (2)
Postulated component malfunctions initiated by a seismic event which could adversely affect the operability of the RPS.
Our letter requested that you review your RPS power supply to determine if your system was susceptible to the same adverse possibilities that the staff had identified for Hatch 2.
We have completed our review of your response to our request and have determined that the power supply RPS design at your facility is such that it could experience the same adverse conditions as described above.
Accordingly, we have determined that modifications should be performed to provide fully redundant Class lE protection at the interface of the non-Class lE power supplies and the RPS. We believe that the use of alarms or shift surveillance is acceptable as an interim measure but is not adequate for the long-term solution of our concerns.
We have found that the conceptual design proposed by the General Electric Company and the installed modification on Hatch I are acceptable solutions to our concern.
010070 s
i "r. Robert L. Smith In view of the above, we believe that you should modify the power supply for the RPS at your facility. This modification should be implemented by the end of the next refueling outage. Should this scheduled outage occur within the next six months, the modifications should be accomplished by the end of the subsequent refueling outage. We will perform a post-implementation review of your modification and will require appropriate Technical Specifications for the system.
We request that you provide within 60 days of your receipt of this letter: your (1) commitment to install a Class lE system, (2) schedule for completion of the modification and (3) schedule for submission of design information and prcposed Technical Specifications.
Sincerely, 7//
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5uThomaQs".pIppolitc, Chief Operating Reactors Branch #2 Division of Licensing cc:
See next page O
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Mr. Robert L. Smith cc:
Mr. W. F. Conway John R. Stanton, Director Vice President and Manager Radiation Control Agency of Operations Hazen Drive Vermont Yankee Nuclear Power Concord, New Hamoshire 03301 Corooration P. O. Box 157 John W. Stevens Vernon, Vermont 05602 Conservation Society of Southern Vermont Mr. Louis H. Heider, V.P.
P. O. Box 256 Vermont Yankee Nuclear Powen Townshend, Vermont 05353 Corocration 25 Research Drive Dr. Mars Longley, Director Westboro, Massachusetts 01581 Occuoational & Dadiological Health 10 Baldwin Street John A. Ritscher, Esouire Montpelier, Vermont 05602 Ropes & Gray 226 Franklin Street New England Coalition on Nuclear Boston, Massachusetts 02110 Pollution Hill and Dale Fann Laurie Burt West Hill - Faraway Road Assistant Attorney General Putney, Vermont 05346 Environmental Protection Division Attorney General's Office Public Service Board J
One Ashburton Place,19th Floor State of Vermont Boston, Massachusetts 02108 120 State Street Montpelier, Verront 05602 Ronald J. Wilson 81018th Street, N. W.
W. P. Murohy, Plant Superintendent Suite 802 Vermont Yankee Nuclear Power Washington, D. C.
20006 Corporation P. O. Box 157 Honorable M. Jerome Diamond Vernon, Vermont 05354 Attorney General State of Vermont David White 109 State Street Co-Director Pavilion affice Building Vermont Public Interest Montoelier, Vermont 05602 Reserach Grouo, Inc.
26 State Street Mr. J. E. Griffin, President Montoeiler, Vermont 05602 Vermont Yankee Nuclear Power Corocration Vermont Yankee Decommissioning 77 Grove Street Alliance Rutland, Vermont 05701 5 State Street Box 1117 Vermont Yankee Decommissioning Montoelier, Vermint 05602 Alliance 127 Main Street Brooks Memorial Library Brattleboro, Vernont 05301 224 Main Street Brattleboro, Vermont 05301
Mr. Robert L. Smith 4-cc; Resident Inspector c/o U. S. NRC P. O. Box 176 Vernon Vermont 05453 1
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