ML20147G442

Requests That Enforcement Discretion Be Used to Grant Relief from Requirements of Tech Spec 4.6.3.C.6 for Limited Period from Heatup Until Completion of Surveillance Prior to Criticality

ML20147G442
Person / Time
Site:	Rancho Seco
Issue date:	02/25/1988
From:	Andognini G SACRAMENTO MUNICIPAL UTILITY DISTRICT
To:	Martin J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
References
GCA-88-129, NUDOCS 8803080230
Download: ML20147G442 (3)

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'o kSMUD SACRAMENTO MUNICIPAL UTIUTY DISTRICT C P. o. Box 16830 Sacramento CA 9585NOUM16) 452-3 AN ELECTRIC SYSTEM SERVING THE.HEQT UF CALIFORNIA GCA 86-129 ICGION y 00 2b (3 g February 25, 1988 U.S. Nuclear Regulatory Commission Attn: J. B. Martin, Regional Administrator Region V 1450 Maria Lane, Suite 210 Walnut Creek, CA 94596 Docket No. 50-312 Rancho Seco Nuclear Generating Station License No. DPR-54 TDI DIESEL GENERATOR 24-HOUR RUN

Dear Mr. Martin:

The District understands that the Regional Administrator may grant relief from Technical Specification Limiting Conditions for Operation when a license amendment would not be appropriate. At this time, the District does not consider that a license amend-ment is appropriate and requests that anforcement discretion be used to grant relief from the requirements of Rancho Seco Techni-cal Specification 4.6.3.C.6.

The bases for this Technical Specification indicates this test is required to demonstrate the TDI diesel generators' capability to provide power for operation of safety features equipment. The bases further state that the loading would be between 3000 and 3300 kw for the surveillance. This is to verify capability of the diesel generators to handle a rated load of 3300 kw, a figure well in excess of any safety loads the diesel generators would carry during an emergency condition.

During the performance of pre-operational testing, Special Test Procedures, STP.ll34 A&B were performed on the TDI diesel generators GEA2 and GEB2, during which loads were maintained between 2900 and 3000 kw. Based on the discussion below, the District believes that operation without re-testing these diesel generators to the higher loading levels will not place the plant in an unsafe condition because the maximum emergency load the TDI diesels would experience is 1700 kw. The District proposes to complete the required surveillance after heatup but prior to criticality.

8803080230 800225 PDR ADOCK 05000312

$ PDR fial RANCHO SECO NUCLEAR GENERATING STATION O 14440 Twin Cities Road. Herald CA 95638 9799;(209) 333 2935

J. B. Martin GCA 88-129 Further testing of the TDI diesel generators prior to heatup to satisfy the requirements of the referenced Technical Specifica-tion will add at least four days to the restart schedule.

Scheduling the tests to occur after heatup but prior to critical-ity will not impact the schedule.

The requirements stated in Technical Specification 4.6.3.C.6 were not met for the following reasons:

1) The test procedures limited the loads to a maximum of 3000 kw due to concern over the value of the then-undetermined "acceptable qualified load." At the time the procedures were developed, it was only known that the engine nameplate rating would be reduced to a "qualified load" because of problems at the Shoreham plant (NUREG-1216, Section 2.1.3.9). Exceeding this load for more than two hours would require engine teardown and inspection of crankshaft and bearings. Since torsiographs had not been performed, and a qualified load had not been determined as acceptable by the NRC, a conservative value of 3000 kw was chosen for maximum loading of the TDI diesels. The results of the recently completed torsiographs indicate that 3300 kw is an accept-able upper limit as stated in Technical Specifications.

2) Specification 4.6.3.C.6. was added to Rancho Seco Technical Specifications by Amendment No. 94, dated February 9, 1988.

The 24-hour run tests were performed prior to NRC approval of the amendment and hence load levels were maintained below 3000 kw to avoid the concerns mentioned above.

The significant factor in this request is that the actual safety features load on the TDI diesel generators is less than 1700 kw.

Based on this actual safety features loading, and the fact that the remaining surveillance test requirements were satiofied by the STps, the District considers that the testing which has al-ready been performed (24-hour runs loaded between 2900 and 3000 kw) clearly demonstrates the ability of the TDI diesel generators to carry all required safety loads. The District is, therefore, requesting relief from Technical Specification 4.6.3.C.6. for the limited period from heatup (RCS >200 degrees F) until completion of the surveillance prior to criticality.

i

J. B. Martin -3 -

GCA 88-129 Please contact me if you have any questions. Members of your staff requiring additional information or clarification may contact Steve Crunk at (209) 333-2935, extension 4913.

Sincerely, ff 9fly/M4

. Ca 1 Andognini Chief Executive Officer, Nuclear cc A. D'Angelo, NRC, Rancho Seco G. Kalman, NRC, Rockville (2)

F. Miraglia, NRC, Rockville D. Crutchfield, NRC, Rockville