ML20236B162
| ML20236B162 | |
| Person / Time | |
|---|---|
| Site: | Braidwood  |
| Issue date: | 02/28/1989 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20236B157 | List: |
| References | |
| NUDOCS 8903200387 | |
| Download: ML20236B162 (3) | |
Text
_
+
ausg%
UNITED STATES j
NUCLEAR REGULATORY COMMISSION g
<j WASHINGTON, D. C. 20665
'(...../
j SAFETY EVALUATION BY THE-OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.14 - TO FACILITY OPERATING LICENSE NO. NPF-72 COMMONWEALTH LCISON COMPANY H
BRAIDWOOD STATION, UNIT 1 1
DOCKET NO. 50-456
/
j-p
1.0 INTRODUCTION
By applications dated October 26, 1988, and supplemented November 22, 29, 1988 and December 5, 1988 Commonwealth Edison Company (Ceco) has requested a change to avend Appendix A, Technical Specifications of Facility Operating License NPF-72. The proposed amendment requests a change to Technical Specification 4.8.1.1.2f to extend on a one-time basis, the previously accepted 31-month surveillance testing requirement for Diesel Generators 1DG01KA and IDG01KB, for.
i an. additional 7 months, until'the first refueling outage for Braidwood Sta'tton Unit 1.
K j
2.0 EVALUATION The NRC staff.h,as reviewed the licensee's pro)osal and the accompanying i
analysis of its significance.
In addition, t1e NRC staff has reviewed the i
operating history of the Diesel Generators at Braidwood, the scheduled surveillance, and the licensee's program for monitoring the Diesel Generators during the extended initial inspection interval. The NRC staff's evaluation of the proposed change, which addresses both the immediate and long term effects, is discussed below 3
I The NRC staff's concern is for any potential impact on Emergency Diesel Generator (EDG)- reliability as a consequence of extending the first EDG inspection interval by as much as 7 months over the already extended interval of 13 months. To evaluate the impact, the NRC staff has reviewed the licensee's submittal, the EDG surveillance requirements, the Braidwood EDG operating history, the industry experience with this type of EDG, and the licensee's program for monitoring EDG surveillance / condition. To date, EDG 1
IDG01KA has operated in excess of 300 hours0.00347 days <br />0.0833 hours <br />4.960317e-4 weeks <br />1.1415e-4 months <br /> and has experienced a total of 154 valid starts (both planned and unplanned) with only five failures. The EDG, IDG01kB, has operated in excess of 350 hours0.00405 days <br />0.0972 hours <br />5.787037e-4 weeks <br />1.33175e-4 months <br /> and has experienced 179 valid starts with a total of only nine failures.
During the period from February 1988
]
to February 1989, the diesel generators have experienced only one failure in 28 valid starts. This single failure was due to the failure of an auto-voltage regulator failure.
Based on the above operating history, the EDGs at Braidwood Unit 1 have a demonstrated reliability which is equal to or better than the industry average.
Betweennowandthefirstrefuelingoutage(scheduledforSeptember1989),the 8903200387 890p g t
PDR ADOCK 05000436 r
P PDC
m 1
n
,(
i
^
. n.
'* l..
- i i
I{
2.
I l
1 EDGs will be tested at least once in every 31 days to demonstrate ongoing
' operability. Successful testing during this period will enhance the 1
a reliability figures.
In addition to the normal surveillance testing done on the EDGs, CECO has had Cooper industries, Energy Services Group, the diesel generator vendor, perform an analysis using the ENSPEC 3000 Engine Analyzer. The data evaluated q
critical parameters, such as engine pressure, temperature, and vibration. All operating parameters were well within the manufacturer's' specifications.
Additionally,'these data will provide the basis against which the periodic analysis results will be compared to determine any significant changes or trends. Engine analysis will provide valuable information regarding continued i
F.DG operability or, if applicable, degradation of operability. Analysis results showing engine _ degradation would provide advance warning of EDG failure j
(excepting catastrophic).in sufficient time to allow for safe plant shutdown.
In' addition to the engine analysis performed on the EDGs, CECO requested Westinghouse.to support, from a probabilistic risk assessment (PRA)
]
perspective, the extension of the teardown inspection requirement in the Technical Specifications, from a one-time 31-month interval to a one-time 38-month interval. Westinghouse concluded that, the proposed extension of the diesel generator. teardown inspections from 31 months to 38 months is acceptable as long as the trend analysis program, which is in place, continues with no i
. indications of significant degradation of the critical engine parameters specified by the manufacturer. The NRC staff agrees with this evaluation done by Westinghouse since the change does not add or modify any existing equipment, nor.. introduce a new mode of plant Operaticn. The~ operability of the' diesel generators will > continue to be verified by performing the other related
-Technical Specification required surveillance, which remain unchanged. As such, the possibility of a new or different kind of accident from any previously evaluated is not created.
At the present time, there are no known generic problems with emergency diesel
-generators produced by Cooper-Bessemer for nuclear service which would challenge the demonstrated reliability of the Braidwood Unit 1 EDGs.
Based on the above evaluation, and the ENSPEC 3000 results, the NRC staff concurs.with the licensee'.s safety analysis, and concludes that extending the l
first interval for EDG inspection by approximately 7 months is acceptable.
The proposed Technical Specification change is, therefore, acceptabie.
3.0 ENVIRONMENTAL CONSIDERATION
.This amendment involves a change in the installation or use of the facilities j
comp 3nents located within the restricted areas as defined in 10 CFR 20. The 1
NRC staff has determined that this amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that l,
~ may be released offsite and that there is no significant increase in individual l
or cumulative occupational radiation exposure. The Coninission has previously issued a proposed finding that this amendment involves no significant hazards consideration and there has been no public comment on such finding.
l 4
I l
l
..y,
,i
,.4e..,'
\\
i
]
- i..
3 j
l I
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 or environmental assessment need be prepared in
'1 connection with the issuance of this amendment.
4.0 CONCLUSION
We have concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health.and safety of the public will not-i be endangered by operation in the proposed manner, and.(2) such activities will be conducted in compliance with the Connission's regulations and the ' issuance of this amendment will not be inimical to the common defense and security or to-the health and safety of. the public..
]
Principal Contributor:
S.-P. Sands Dated:
February. 28,1989 i
q
'I I
I l
_j