ML20134J971
| ML20134J971 | |
| Person / Time | |
|---|---|
| Site: | River Bend  |
| Issue date: | 11/12/1996 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20134J966 | List: |
| References | |
| NUDOCS 9611180160 | |
| Download: ML20134J971 (3) | |
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p uouqk UNITED STATES NUCLEAR REGULATORY COMMISSION f
WASHINGTON, D.C. 2066H001
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 89 TO FACILITY OPERATING LICENSE NO. NPF-47 ENTERGY OPERATIONS. INC.
RIVER BEND STATION. UNIT 1 DOCKET N0. 50-458 l.0 INTRODUCTION By application dated August 1, 1996, Entergy Operations, Inc. (the licensee) requested changes to the Technical Specifications (Appendix A to Facility Operating License No. NPF-47) for the River Bend Station, Unit 1.
The proposed changes would revise the technical specifications (TSs) to incorporate requirements for limiting the time that the hydrogen mixing isolation valves on the drywell are open. The requirements were contained in the old TSs and with the conversion to the Improved Standard Technical Specifications, the requirements were inadvertently changed. The proposed action is to restore requirements to meet the licensing basis for the River Bend Station.
The proposed amendment would also' change the time from 7 days to 31 days to determine the cumulative time the valves are open.
2.0 BACKGROUND
The licensing basis for the drywell hydrogen mixing system was established during the licensing of the River Bend Station and is documented in NUREG-0989
" Safety Evaluation Report related to the operation of River Bend Station" Supplement 2, dated August 1985. The Containment Purge System is addressed in section 6.2.4.3; the hydrogen mixing system for drywell pressure control was found acceptable as follows:
"The concern regarding the use of the hydrogen mixing system for drywell pressure control is the potential of it becoming a suppression pool bypass leakage path. The applicant stated that the suppression pool bypass area with the 6-inch hydrogen mixing system inlet valve open is 0.20 ft sq which is bounded by the allowable bypass leakage. Therefore, the staff finds the applicant's proposal to use the hydrogen mixing system for drywell pressure control to be acceptable. However, since the applicant has not demonstrated that these valves are capable of closing under accident conditions in the drywell, certain restrictions apply.
Technical Specification 3.6.6.2 specifies that in Operating Modes 1 and 2, the total number of hours used should not exceed 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> /365 days and in Operating Mode 3 the number of hours should be limited to 90 hours0.00104 days <br />0.025 hours <br />1.488095e-4 weeks <br />3.4245e-5 months <br /> /365 days".
9611100160 961112 DR ADOCK OSOO 8
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. By license amendment number 81 issued July 20, 1995, the River Bend Station technical specifications were converted to the new Improved Standard Technical Specification format and content. During the conversion of the TSs to the improved, the licensee inadvertently adopted the new format for the hydrogen mixing valves and dropped the standing requirement for limiting the valves open during Modes 1, 2, and 3.
The staff also inadvertently adopted the licensee's submittal and issued the new TSs without the requirements to continue to meet the licensing basis.
3.0 EVALUATION The licensing basis for operation of the drywell hydrogen mixing valves has not changed and remains valid. The licensee has not demonstrated that the valves are capable of closing under accident conditions in the drywell and the restrictions continue to apply. The prior TSs were imposed at the time of licensing and should continue. The licensee's proposal to revise the new TSs is consistent with the prior TSs and the licensing basis for the facility and is acceptable, l
The licensee also proposes to change the time for determining the cumulative time the valves are open from 7 days to 31 days. Under the restrictions to minimize the open time for the valves, any opening is rare.
TSs 3.6.5.3.1 requires that the valves be verified to be closed every 31 days. The l'.censee proposes to combine the period for verifying the valves to be closed with the i
period for determining the cumulative open time for the valves.
Since the valves are maintained closed and any opening would be controlled (and accounted for) in order to limit the cumulative time and stay within the TSs, the requirement to determine the cumulative time every 7 days is also overly conservative. The determination for cumulative time is an accounting process with no direct requirement to verify the opening or closing of the valves.
Having the accounting of cumulative time for opening accomplished at the same time as the required verification of valve position, the licensee is directed to more than one action on the same valves at the same time.
We agree with the licensee that accounting of cumulative time for opening of the valves every 31 days is reasonable and is acceptable.
We have reviewed the technical specifications proposed by the licensee and find them acceptable. We have also reviewed the Bases provided by the licensee and the proposed changes are approved.
4.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Louisiana State Official was notified of the proposed issuance of the amendment. The State official had no comments.
5.0 ENVIRONMENTAL CONSIDERATION
The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves no
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9 i significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issu.ed a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (61 FR 50343). Accordingly, the 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 connection with the issuance of the amendment.
6.0 CONCLUSION
The Commission has concluded, based on the considero 3.ons discussed above, that:
(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor: David Wigginton Date:
November 12, 1996