ML20082P342
| ML20082P342 | |
| Person / Time | |
|---|---|
| Site: | Fort Calhoun  |
| Issue date: | 09/04/1991 |
| From: | Gates W OMAHA PUBLIC POWER DISTRICT |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| GL-88-17, LIC-91-201R, NUDOCS 9109100294 | |
| Download: ML20082P342 (2) | |
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Omaha Public Power District 444 South 10th Street Mall September 4, 1991 OmMa Nebrana 68102 P.247 LIC 91-20lR 402/G30'2000 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Mail Station Pl-137 Washington, DC 20555
References:
1.
Docket No. 50 285 2.
Letter from NRC (D. M. Crutchfield) dated October 17, 1988 (Generic letter 88-17) 3.
letter from OPPD (W. G. Satas) to NRC (Document Control Desk) dated April 12, 1990 (LIC-90-0284)
Gentlemen:
SUBJECT:
Generic Letter 88-17 Enhancements The purpose of this letter is to revise Omaha Public Power District (0 PPD) commitments made in response to Generic letter 88-17 (Loss of Decay Heat Removal).
The intent of this Generic Letter was to provide actions to minimize the initiation and consequences of loss of decay heat removal through implementation of expeditious actions and recommended programmed enhancements.
In Reference 3, OPPD indicated that portions of a modification (MR-fC-89-019) would be installed to provide some enhancements as recommended in the Generic Letter.
These enhancements were intended to provide additional status indication to Control Room operators for the shutdown cooling (decay heat removal) system, and were to include the addition of a shutdown cooling low flow alarm and the addition of pressure indication at the suction of the Low Pressure Safety injection (LPSI) and Containment Spray (CS) pumps.
OPPD has subsequently re-analyzed the technical and cost-benefit aspects of this modification relative to meeting the intent and requirements of the Generic Letter.
As noted in Reference 3, other installed instrumentation and alarms provide adequate continuous performance monitoring capability of the system as required by the Generic Letter, fort Calhoun Station Unit No. I presently has numerous indications available in ihe Control Room to monitor Decay Heat Removal (DHR) system performance.
These indications include real time confirmation of level, flow, pressure, temperature, valve position and pump motor amperage.
In addition to the Control Room indications, there are numerous associated audible alarms which could alert operators to possible DHR system problems.
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LIC 91 20lR Page 2 Installation of the shutdown coolino low flow alarm, combined with the aforementioned existing alarms, will provide the Control Room operators with more than adequate visible and audible indications of abnormal conditions in the DHR system as recommended by Generic letter 88-17.
However, the addition of pressure indication at the suction of the LPSI and CS pumps would not provide information to the operators significantly different or more valuable than that provided by the instrumentation noted above. OPPO has thus determined that installing suction pressure gruges would provide minimal additional benefit in assuring adequate decay heat removal.
Consequently, OPPD is informing the NRC of our intention to revise the commitment made in Reference 3.
The shutdown cooling low flow alarm will still be installed under modification MR fC-89 019; however, the pressure indication on the suction of the LPSI and CS pumps will not be installed.
Modification MR-fC-89-019 is scheduled for installation during the 1992 refueling outage, if you thould have any questions, please contact me.
Sincerely, AV N. <W W. G. Gates Division Manager Nuclear Operations WGG/sel c:
LeBoeuf, Lamb, Leiby & MacRae R. D. Martin, NRC Regional Administrator, Region IV W. C. Walker, NRC Project Manager R. P. Mullikin, NRC Senior Resident inspector i
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