ML18057A551
| ML18057A551 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 10/30/1990 |
| From: | Slade G CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-88-004, IEB-88-4, TAC-69948, NUDOCS 9011070246 | |
| Download: ML18057A551 (2) | |
Text
consumers Power POW ERi Nii MICHlliAN"S PROliRESS Palisades Nuclear Plant: 27780 Blue Star Memorial Highway, Covert,,Ml 49043 October 30, 1990 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT -
GB Slade General Manager COMPLETION OF ACTIONS MADE IN RESPONSE 'TO NRC BULLETIN 88 POTENTIAL SAFETY RELATED PUMP LOSS (TAC NO. 69948)
By letter dated July 7, 1988, Consumers Power Company provided our response to
- the subject bulletin. Seven systems were identified as h~ving the potential for a loss of a pump stemming fr-om either dead heading the pump(s) with common minimum flow recirculation lines or from inadequate minimum flow capacity.
In the.response, several commitments were made to address the concerns identified for four of the systems (Auxiliary Feedwater, Containment Spray, High Pressure Injection and Low Pressure Injection)., On August 11, 1989, Consumers Power Company updated the status of the commitments made in our initial response to the bulletin and closed out action on the containment spray system.
This submittal delineates the completion of the actions taken with respect to NRC Bulletin 88-04.,
AUXILIARY FEEDWATER SYSTEM (AFW)
From our previous response~, a, concern was identified ~egarding AFW pump P-8C exhibiting signs of hydraulic instability during minimum flow operation.
To address these concerns, a test was conducted during the 1989 Fall Maintenance Outage to establish the flow conditions required for the onset of low flow hydraulic instability of AFW pump P-8C. The test results were used to establish administrative control of AFW pump P-SC op~rations. System Operation Procedure (SOP) 12, "Feedwater System", was revised to include operating limitations for AFW pump P-8C. Administrative control of AFW pump P-8C operation will minimize the time that the subject pump is allowed to operate at low flow conditions which could induce hydraulic instability.
Also, during the 1989 Fall Maintenance Outage~ an inspection of the first stage impeller was performed.
It identified minor pitting_ of a few vanes that could possibly be attributed to hydraulic instability.
Based on the inspection observations, the identified pitting had not affected the integrity of the pump.
9011070246 901030 PDR ADOCK 05000255 P
PNU
- -:~:..
. _: _;,..L A CMS' ENERGY COMPANY
The impeller vanes were returned to their original finish to prevent acceleration of impeller damage.
Since administrative control of AFW pump P-8C has been established -and no significant damage was found in the inspection of _the first stage impeller, modification of the system is not deemed to be required.
These actions close out our previous commitments with regard to the AFW syste~.
HIGH AND LOW PRESSURE SAFETY INJECTION (HPSI/LPSI)
From our previous responses, no immediate ~oncerns were identified regarding the HPSI or LPSI pumps relative ~o the bulletin. However, we did commit to revise the LPSI {ESS-M-1} and HPSI (ESS-M-7} pump maintenance procedures to incorporate inspection instructions regarding damage due to recirculation or cavitation.
The required procedure (ESS-M-1 and ESS-M-7} revisions have been implemented.
All actions needed to address the bulletin have been completed.
~/]~
Gerald B Slade.
General Manager
- CC Administrator, Region 111,*USNRC NRC Resident Inspector, Palisades