ML18054B342

Requests Approval of Proposed Surveillance Test Method for Containment Spray Pumps W/O Rendering Associated LPSI Pump Inoperable,In Response to Confirmatory Action Ltr CAL-RIII-86-02 Dtd 860521

ML18054B342
Person / Time
Site:	Palisades
Issue date:	12/28/1989
From:	Berry K CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
CAL-RIII-86-02, CAL-RIII-86-2, NUDOCS 9001050093
Download: ML18054B342 (4)

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consumers Power Kenneth W Berry Director POWERiNii Nuclear Licensing MICHlliAN'S PROliRESS General Offices: 1945 West Parnall Road, Jackson, Ml 49201 * (517) 788-1636 December 28, 1989 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT - SURVEILLANCE TEST METHOD FOR CONTAINMENT SPRAY PUMPS - UNREVIEWED SAFETY QUESTION In response to the NRC's Confirmatory Action Letter CAL-Rlll-86-002 dated May 21, 1986, Consumers Power Company developed a Material Condition Task Force (MCTF). One action from the MCTF was for Consumers Power Company to develop a new surveillance test method to test the containment spray pumps without rendering the associated Low Pressure Safety Injection (LPSI) pump inoperable.

Consumers Power Company has developed a new test method for testing the containment spray pumps P54A, P54B and P54C. The new method provides three major improvements. First, the new method *eliminates the need to make the LPSI pump inoperable in order to conduct the test. Second, increased flow rates are possible providing higher quality data to determine pump performance. Third, the new flow route makes possible the quarterly testing of most Containment Spray system check valves. However, during the 10CFR50.59 review an unreviewed safety question was identified and prior NRC approval of the test method is required. CPCo requests NRC review and approval of the new test method.

The previous test method (see Attachment I) recirculated water through the two-inch minimum recirculation lines back to the SIRW tank. This flow path to the SIRW tank was isolable via CV-3027 and CV-3056 from the Control Room. However, the previous test method required the associated LPSI pump to be removed from service to prevent backflow through the pump from the minimum recirculation header.

The new test method (see Attachment II) provides a flow path through the six inch SIRW tank fill valve MV-3225. This flow path is not isolable from the Control Room. The new test method makes possible flow rates of 1000 gpm which provides for higher quality trending data and does not require the associated LPSI pump inoperability. In addition, containment spray header check valves and the spray pump discharge check valve are tested with the new test method.

The spray header check valves CK-3216 and CK-3226 are tested by providing a flow path through valves MV-3217, MV-3227 and MV-3237 to the SIRW Tank. This flow path allows approximately 70 gpm for the test of the spray header check valves.

Palisades believes the new test method is an unreviewed safety question for two

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Palisades Plant Nuclear Regulatory Commission Surveillance Test Method December 28, 1989

• 2 reasons. First, if a LOCA occurs while the test is in progress and MV-3225 is open, then flow from the spray header is diverted back to the SIRW tank.

Second, the proposed test method provides a potential radiological release path should a LOCA occur with MV-3225 open because any flow diversion after a recirculation actuation signal would put contamination from the containment sump into the SIRW tank, where it could be released via the tank vent. Manual operator action would be required to close MV-3225, MV-3217 and MV-3227 in order to restore licensing basis spray flow and to eliminate the release path.

Palisades believes the proposed test method does not present a significant safety hazard for a number of reasons. First, a dedicated operator will be placed in the room containing the valves in order to close them during an accident. The operator would have at least 20 minutes to perform this action before radioactive containment sump water would be recirculated into the engineered safeguards pumps. Second, MV-3225 is throttled to limit flow.

This throttling limits the diversion flow rates to approximately 1000 gpm and acts as a restriction for potential radiation releases. An analysis has been performed which demonstrates that diversions up to 1475 gpm are acceptable under the expected plant accident response which starts all three containment spray pumps. If a single failure occurred preventing all three pumps from delivering flow, the manual operator action to close the valves would restore the required flow. Finally, testing would be performed approximately four hours every quarter (four hours out of 2184 hours0.0253 days <br />0.607 hours <br />0.00361 weeks <br />8.31012e-4 months <br />) while at power operations. The probability of a LOCA during testing is considered to be very small. Additionally, the probability of an operator failing to close appropriate test valves is small. Thus, the overall probabilities of a LOCA and a operator error support testing per the proposed method.

CPCo requests that the proposed test method be approved to permit higher quality test data for the reasons presented. Permission to test as presently outlined above is requested as quickly as possible.

~~

Kenneth W B~rry ~

Director, Nuclear Licensing CC Administrator, Region III, USNRC NRC Resident Inspector - Palisades Attachments CAL-Rlll-86-002-LIOl

• ATTACHMENT 1 PREVIOUS TEST METHOD CONTAINMENT SPRAY PUMPS CV-3056 CV-3027

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CONTAINMENT SPRAY PUMP

• l ATTACHMENT 2 NE\11 TEST METHOD CONTAINMENT SPRAY PUMPS 3237 NLC NLC

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TANK 3002 NC NO E-608 CONTAINMENT SPRAY PUMP