ML20215D339
| ML20215D339 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 12/01/1986 |
| From: | Robe R COMMONWEALTH EDISON CO. |
| To: | Case E Office of Nuclear Reactor Regulation |
| References | |
| RAR-86-39, NUDOCS 8612160329 | |
| Download: ML20215D339 (3) | |
Text
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O Commonwealth Edison Quad Cities Nt clear Power Station 22710 206 Avenue North Cordova. Illinois 61742 Telephone 309/654-2241 RAR-86-39 December 1, 1986 Mr. Edson G. Case, Deputy Director Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C.
20555
Dear Mr. Case:
Enclosed please find a listing of those changes, tests, and experiments completed during the month of November, 1986, for Quad-Cities Station Units I and 2, DPR-29 and DPR-30. A summary of the safety evaluation is being reported in compliance with 10 CFR 50.59.
Thirty-nine copies are provided for your use.
Respectfully, COMMONHEALTH EDISON COMPANY QUAD-CITIES huCLEAR POWER STATION W
e R.A. Robe /
Services Superintendent bb Enclosure cc:
I. Johnson J. Leider/E. Budzichowski 0612160329 061201 PDR ADOCK 05000254 R
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4-4 Modification.M-4-1/2-85-14 Description
'This modification was initiated to install a switch at the auxiliary control panel to allow manual selection of the power source for the 1/2 Diesel Generator Cooling Water Pump.
In the event that the cables between Bus 18 and the 1/2 Diesel Generator Cooling Water Pump are damaged, power for the pump can be obtained from Bus 28'by placing the selector. switch to the '28' position. This action will cause a transfer of the power supply for the 1/2 Diesel Generator Cooling Water Pump from Bus 18 to Bus 28.
When the switch is in the ' NORMAL' position the existing transfer logic.
for an undervoltage condition on Bus 18 is not affected.
This modification was required to ensure compliance with safe shut-down criteria per 10 CFR 50.48, Appendix R.
Evaluation This modification ensures that power will be available for the 1/2 Diesel Generator Cooling Water Pump under all plant conditions and thus increases the level of safety for.the plant.
I a.
Modification M-4-2-81-24 Description This modification provides a more extensive suppression pool tempera-ture monitoring system from which an average ' bulk' temperature is derived.
This was accomplished by installing 16 thermocouples symmetrically around the suppression chamber, at the normal center of gravity of the water mass.
-These.16 thermocouples-are divided into 2 channels, 8 thermocouples apiece.
These signals are sent to a strip chart recorder in the main Control Room along with the average temperature value for that channel.- Each channel has an individual high temperature (200*F) alarm and a bulk high temperature (110*F) alarm associated with it.
Evaluation By installing this modification more reliable local and average suppression pool tenperature values can be obtained.
Failure of this equipment would create the same conditions as existed prior to this-modifi-cation. The margin of safety is increased by installing this modification.
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