RBG-22-146, Application for Amend to License NPF-40,revising Tech Specs to Increase Rated Steady State Voltage from 115% to 130% During HPCS Diesel Generator Surveillance Tests.Fee Paid

Application for Amend to License NPF-40,revising Tech Specs to Increase Rated Steady State Voltage from 115% to 130% During HPCS Diesel Generator Surveillance Tests.Fee Paid

ML20132B892
Person / Time
Site:	River Bend
Issue date:	09/24/1985
From:	William Cahill GULF STATES UTILITIES CO.
To:	Harold Denton Office of Nuclear Reactor Regulation
Shared Package
ML20132B894	List: ML20132B897 RBG-22-146, Application for Amend to License NPF-40,revising Tech Specs to Increase Rated Steady State Voltage from 115% to 130% During HPCS Diesel Generator Surveillance Tests.Fee Paid
References
RBG-22-146, NUDOCS 8509260336
Download: ML20132B892 (4)

Text

C GULF STATES UTILITIES C'OMPANY RIVf R SEND STATION POST OntCf Brx 220 ST FRANCISVILLE LOUISiAN A 7U775 ARE A CODE 504 635 6094 346 8651 September 24, 1985 RBG- 22,146 File Nos. C9.5 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Ccmnission Washington, D.C. 20555

Dear Mr. Denton:

River Bend Station - Unit 1 Docket No. 50-458 Gulf States Utilities (GSU) hereby files an application for an amend-ment to the River Bend Station Unit 1 Technical Specifications, Appendix A to Facility Operating License NPF-40, pursuant to 10 CPR 50.90. Enclosure 1 contains the information for Staf f review of this request. Enclosure 2 provides the requested revisions to the River Bend Station Technical Speci-fications. As discussed in Enclosure 1, these revisions to the Technical Specifications are required to allow River Bend Station to achieve the startup schedule and therefore represent anergency circumstances as dis-cussed in 10 CFR 50.91.

Pursuant to 10 CFR 170.12, GSU has errlosed a check in the amount of one-hundred ard fifty dollars ($150.00) for the license amendment applica-tien fee. Pursuant to 10 CFR 50.91(b) (1) , the State of Iouisiana, Depart-ment of Envirorrnental Quality - Nuclear Energy Division has been notified of this amendnent request. Additionally the Regional Mministrator of Region IV and the Senior Resident Inspector have been provided copies of this application. Your prcxupt attention to this application is appreciat-ed.

Sincerely,

/

. J. Cahill, .

Senior Vice President River Bend Nuclear Group Enclosures WJC/EEG/je \

00 8509260336 850924 PDR ADOCK 05000458 I)

P PDR Q Y uthMectsW#

P ENCIDSURE 1 I. Safety Evaluation and No Significant Hazards Determination Technical Specification 4.8.1.1.2(f) (3)

'Ihe technical specification currently requires an 18-month surveil-lance of the high pressure core spray (HPCS) diesel generator (1C) to denenstrate its ability to reject a full load of 2500-2600 kw without tripping and not exceeding a transient generator voltage of 4784 volts during and following the load rejection. The 4784 volts is 115 percent of the rated steady state voltage of 4160 volts. This change request is to revise the surveillance test to verify that the tran-sient generator voltage shall not exceed 5400 volts (approximately 130 percent of the rated steady state voltage) .

Safety Evaluation

'Ihe River Bend Station HPCS electrical system is designed for a maxi-num transient voltage overshoot following a full load rejection of 5824 volts. This is 140 percent of rated steady state voltage (4160 volts). In order to perform this surveillance test, the main output breaker of the HPCS diesel generator is opened. Therefore, only the electrical wiring and cmponents on the HPCS diesel generator side of the main output breaker are subjected to the transient voltage. All of this electrical wiring and cmponents have been designed to with-stand 140 percent of rated steady state voltage without any degrada-tion.

'Ihe voltage regulator has been set to provide optimum performance during starting, loading and load rejection transients. This optimi-zation results in stable starting and loading transients and the voltage overshoot in excess of that currently allowed but less than the design allowable.

This change request will provide the necessary operational flexibili-ty in surveillance testing while providing an adequate safety margin to the design voltage limit while not affecting the reliability of the systan. Enclosure 3 provides full load rejection test data.

No Significant Hazards Evaluation The proposed amendment to the technical specifications would not involve a significant increase in the probability or consequences of an accident previously evaluated because there is no change in the design or perfonnance of plant systems or canpenents frun those eval-uated in the Final Safety Analysis Report (FSAR) . The proposed revi-sion is consistent with the accident analyses described in the FSAR.

m Since the proposed amendnent does not change any previously reviewed and approved description or analysis described in the FSAR, the pro-posed anendment does not create the possibility of a new or different kind of accident, nor does not involve a significant reduction in a margin of safety.

II. Pevised Technical Specifications

%e requested revision is provided as Enclosure 2.

III. Interim Ccnpensatory Measures River Bend Station currently meets the requirenents of Technical Specifications applicable prior to achieving initial criticality.

'Iherefore, no interim ccupensatory measures are required.

IV. Bases for Emergency Circumstances The River Bend Station Technical Specification surveillance require-ment 4.8.1.1.2.f.3 as provided in Appendix A to the River Bend Sta-tien Unit 1 Facility Operating License NFP-40, is consistent with the Final Safety Analysis Report and HPCS Diesel Generator design. The Technical Specification was accepted by GSU based on expected perfor-mance.

We HPCS diesel generator is required to be operable for initial criticality (Operational Mode 2) and thus must satisfy this surveil-lance requirenent. Initial criticality is currently scheduled for October 3, 1985.

Howver, the evaluation of recent baseline testing for the HPCS die-sel generator (performed on September 15, 1985) and optimization setting of the voltage regulator has shown that the Technical Speci-fication Surveillance Requirement 4.8.1.1.2.f.3, which requires that the HPCS diesel generator not exceed 115 percent of rated steady state voltage during the load rejection test, is not achievable and requires inmediate revision to prevent delay of the River Bend Sta-tion startup schedule.

V. Schedule for Attaining Ccupliance As indicated in Item III above, River Bend Station is currently in ccupliance with the applicable Technical Specifications.

VI. Notification of State Personnel A copy of this amendannt application is being provided to the State of Louisiana, Department of Environmental Quality - Nuclear Energy Division. The State has been verbally notified of this request.

l l

e VII. Environmental Impact Appraisal The conduct of the surveillance in either its original or amended form (requested herein) does not result in an environmental impact.

Therefore the approval of this amendment does not result in a signif-icant environmental impact nor does it change any previous environ-mental impact statermnts for River Bend Station.