ML20151S057
| ML20151S057 | |
| Person / Time | |
|---|---|
| Site: | Fort Calhoun  |
| Issue date: | 04/19/1988 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20151S034 | List: |
| References | |
| NUDOCS 8804280173 | |
| Download: ML20151S057 (3) | |
Text
_
j ak:
UNITED STATES
~
NUCLEAR REGULATORY COMMISSION a
O I
WASHINGTON, D. C. 20666 k.....
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGUIATION RELATED TO AMENDMENT NO.112 TO FACILITY OPERATING LICENSE NO. DPR-46 OMAHA PUBLIC POWER DISTRICT 6
FORT CALHOUN STATION, UNIT NO. 1 DOCKET NO. 50-285
1.0 INTRODUCTION
By letter dated March 9, 1988, Omaha Public Power District (licensee) requested a change to Facility Operating License No. OPR-40, Appendix A Technical Specifications, for the Fort Calhoun Station, Unit No. 1.
The change proposed would permit interval extension of the surveillance requirements for Diesel Generator No. 1 (DG-1) which is required to be perfomed by April 30, 1988. This one-time interval extension would allow performance of the surveillance inspection during the refueling outage scheduled to begin September 1988. The performance of this surveillance inspection during plant operation could result in the plant entering Limiting Conditions for Operation and require plant shutdown.
Discuss, ion The surveillance requirements of the Technical Specifications require i
the inspection of each diesel generator on a refueling frequency in accor-dance with the manufacturer's recorrcendations for this class of standby service. This Technical Specification requirement is interpreted to require a thorough inspection once every 18 months. The surveillance inspection was last perfomed on DG-1 in October 1986.
In order to meet the Technical Specification surveillance interval, the inspection would have to be perfomed by April 30, 1988.
The diesel generators are designed to furnish reliable in-plant a.c. power adequate for safe plant shutdown and for operation of engineered safeguards when the 345 and 161-kV systems are unavailable. The reliability of DG-1 over the last 100 demands, dating back to December 1979, is 93%. More recently, DG-1 has had a success rate of 95% over the last 20 starts performed since July 1986 The last failure of DG-1 occurred or. December 10, 1986. This failure was attributed to voltage regulator failure. The regulator was replaced and the diesel was successfully retested.
In addition, modification work was performed on DG-1 during the 1987 refueling outage, including the installation of a new high capacity turbocharger.
8804280173 880 85 PDR ADOCK O PDR P
2 i
1,k 2.0 EVALUATION
,> f 6 : q,..T The 18-month test interval for the diesel generators was selected to' be consistent with the maximum anticipated interval between refueling outages."
2 The selection was based on engineering judgement to ".hieve the dual goals of the need to conduct periodic surveillance tests buc not interfere substantially with unit availability. Amendment No. 111 to the Fort Calhoun Station Technical Specifications incorporated the Generic letter 84-15 recomendations and also contained a revision to change the frequency of the surveillance inspection of the diesel generator from an annual basis to one based on times of a refueling frequency. This change was made to preclude scheduling the manufacturer's recomended overhaul (which requires removing the diesel from service) during power operation. This change in interval would minimize the periods of time during normal i
operation that one diesel is out of service for maintenance.
4 In its application, the licensee indicated that the diesel generator v
vendor has stated that the inspection required by the surveillance require-ments can be extended on a one-time basis assuming the perfomance of monthly surveillances and that no unusual operational demands will be placed on DG-1 before the perfomance of the inspection in October 1988.
The licensee is requesting an extension of approximately 6 months from the currently required date for the surveillance inspection. This 6 month extension would permit the Unit to continue operation at sower until the scheduled refueling outage in September 1988. However, t1e licensee has comitted that if, due to an unschedaled outage, the plant is required to be shutdown in Mode 4 for a period of time greater than two weeks prior to the September refueling outage, the required surveillailce inspection will be performed at that time.
The extension of no more than 6 months will not significantly increi.se the probability of undetected degradation for DG-1, based on its previous reliaDie operating history as discussed above. The licensee has indicated that the previously 18-month surveillance on DG-1 noted no deficiencies or degraded components.
3.0 FINDINGS
/
Based upon the details discussed above and the compensatory measure com-nitted to by the licensee, the NRC staff has concluded that the proposed extension of approximately 6 months is acceptable.
. W p 'd 4.0 LNJIRONMENTALCONSIDERATION E,4 -
3 m,4"n si This amendment involves changes to a surveillance requirement. We have determined that tha amendment involves no significant increase in the g yW' amounts, and nu significant change in the types of any effluents that may be released offsite and that there is no significant increase in individual or cumulative cccupational radiation exposure.
The Comission has previously issN e proposed finding that tMs amendment involves
.c y
e l '
no significant hazards consideration, and there has been no public conment on such finding. Accordingly, this amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b), no environmental impact statement nor environmental assessment need be prepared in connection with the issuance of this anendment.
5.0 CONCLUSION
We have concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health and safety of the pubite will not be endangered by operation in the proposed manner, and (2) such activities will be conducted in compliance with the Commission's regulations, ar.d the issuance of the amendment will net be inimical to the common defense and~ security or to the health and safety of the public.
Date: April 19,1988 Principal Contributors: Anthony Bournia 9
4 1
1 1
-