ML19290E077
| ML19290E077 | |
| Person / Time | |
|---|---|
| Site: | Maine Yankee |
| Issue date: | 02/29/1980 |
| From: | Groce R Maine Yankee |
| To: | Reid R Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19290E078 | List: |
| References | |
| WMY-80-32, NUDOCS 8003040193 | |
| Download: ML19290E077 (2) | |
Text
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TURNPIKE ROAD (RT. 9)
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ENGINEERING OF FICE WESTBORO, M ASSACHUSETTS 01581
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617-366-9011 February 29, 1930 B.3.2.1 WY 80-32 United States Nuclear Regulatory Commission Was hington, DC 20555 Attention:
Office of Nuclear Reactor Regulation Mr. Robert W.
Reid, Chief Division of Operating Reactors
References:
(1)
License No. DPR-36 (Docket No. 50-309)
(2)
USNRC letter to All Power Reactors dated August 9,1979 (3) MYAPC letter to USNRC (WMY 79-89) datei September 14, 1979
Subject:
Adequacy of Station Electric Distribution System Voltages
Dear Sir:
As required in Reference (2), we have jus t completed an exhaustive revie w of the electric power systems at Maine Yankee. We recognize that w exceeded the time es timate detailed in our letter, Reference (3) ; however we trus t you will find the ccxnpleteness of this evaluation warrants the additional time.
Our review determined if the offsite power system and onsite electric distribution system is of sufficient capacity with capability to automatically start and operate all safety loads if all onsite power sources are not available. Our analysis which was based on the guidelines of Enclosure 2 of Reference (2) demonstrates that voltage is adequate to start and operate all safety loads. The analysis is contained in the attached report, YAEC #1204,
" Auxiliary Power System Voltage Study for Maine Yankee Atomic Powr Station".
Reference (2) also required that the adequacy of the onsite and offsite power distribution systems be verified by test to assure that the analysis results are valid. Because of the difficulty of simulating high and low voltage conditions in the transmission system together with various conditions in the plant, we have chosen to verify the analysis using our compiter program and our model of the station auxiliary power system to predict bus voltages for actual plant conditions. The verification is also contained i'. the attached report. Comparison of bus voltages predicted by the computer program to actual bus voltages demonstrates that the computer model is valid.
We have also reviewed the electric power systems at Maine Yankee and found total ccxnpliance with GDC-17.
We have determined that, to the extent practical, there are no events or conditions which could result in the simultaneous or consequential loss of both required circuits to the offsite net erk.
P sooaoao R 3
s
'f United States Nuclear Regulatory Commiss ien February 29, 1980 Attn:
Mr. Robert W.
Reid, Chief Page 2 We trus t that this information is satisfactory; however, should you desire additional information, please contact us.
Very truly yours, MAINE YANKEE ATOMIC POWER COMPANY d
bert H. Groce Senior Engineer - Licensing RHG/jgh