ML20002C989
| ML20002C989 | |
| Person / Time | |
|---|---|
| Site: | Big Rock Point File:Consumers Energy icon.png |
| Issue date: | 11/06/1969 |
| From: | Morris P US ATOMIC ENERGY COMMISSION (AEC) |
| To: | Haueter R CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| References | |
| NUDOCS 8101150674 | |
| Download: ML20002C989 (4) | |
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UNITED STATES ATOMIC ENERGY COMMISSION
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Consumers Power Company 212 West Michigan Avenue Jackson, Michigan 49201 Attention: - 1 hr. R. L. Haue ter Assistant Electric Production Superintendent - Nuclear Gantlemen:
In your letter dated September 10, 1969, you review your current operating practices and futura plans regarding the turbine bypass valve system at the Big Rock Point Plant.
You state that the normal roda of operation is with the bypass valve controller in automatic and with the d-c motor-operated isolation valve open.
This code of operation is consistent with our under-standing of the original design intent of the bypass system.
You state further that in the event of valve packing leaks, op3 ration of the p; ant is permitted with the isolation valve closed outti a routine maintenance shutdown can be scheduled.
On the basis of our review of information previously submitted, we concur that operation
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with the bypass valve isolated or in a canual mode for short periods of time is acceptable because analyses of the loss-of-load accident assuming the bypass valve does not open and that auxiliary power is lost indicate that no damage will occur to the primary system or to the fuel, provided that a reactor screa occurs.
"The b pass valve is not required In year ictter you also state that l
for proccetion of the reactor nor is it a factor in any of the accident analyses which were perforced on the plant".
We do not agree with l
this statement.
Continued operation with the bypass valve in ranual, or with the isolation valve closed would, a our judgment, raise two safety questions:
(1) greater reliance smulu be placed on the reactor protection system to prevent fuel damage.n the event of a loss of load; j
and (2) the requirement to scraa on each loss of load would subject critical plant components to a larger nucher of transient thermal f/o//f067Y P00RORIBINhl l
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2-November 6, 1969 Consumers Power Company aycles than were anticipated in the original safety evaluations.
On this basis we do consider that any proposal for extended operation without automatic steam bypass capabilities would involve unreviewed
- safety questions. Before such a mode of operation could be accepted, we would require that the above considerations ts appropriately analyzed and that the results of such analyses be submitted for our evaluation.
Your letter of September 10 also noted your intent to perform another load rejection test at 30 Mwe, but stated that further testing beyond this is not planned. We consider that if the automatic mode of opera-tion of the bypass valve is to be continued, tests at 30 Mwe and at higher power levels should be performed as described in Amendment 14 to your application. These tests should b'a performed in the near future, or you should submit the information described above in support of a proposal to operate with the bypaos :Jalves isolated or in the manual mode.
Please advise us at an early date of your plans in this regard and of your schedule for conducting load rejection tests.
Sincerely, z l t r d M) W L /'
g Peter A. Morris, Director Division of Reactor Licensing 1
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