ML20141F427

Safety Evaluation Supporting Amend 48 to License DPR-45

ML20141F427
Person / Time
Site:	La Crosse File:Dairyland Power Cooperative icon.png
Issue date:	04/14/1986
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20141F417	List: ML20141F412 ML20141F421 ML20141F427
References
NUDOCS 8604230023
Download: ML20141F427 (2)

Text

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g g NUCLEAR REGULATORY COMMISSION UNITED STATES C'ASHINGTON, D. C. 20555 j

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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT N0. 48 TO PROVISIONAL OPERATING LICENSE NO. DPR-45 DAIRYLAND POWER COOPERATIVE LA CROSSE BOILING WATER REACTOR (LACRWR)

DOCKET N/1. 50-409

1.0 INTRODUCTION

By application dated February 4, 1986, as supplemented and clarified by letter dated March 26, 1986, Dairyland Power Cooperative (DPC) (the licensee) reouested a chance to the Technical Specifications of the La Crosse Roilina Water Reactor (LACBWR). The pronosed technical specification change involves modification and replacement of various constituents of the IC Non-InterruDtible Rus. The primary load suoported by the IC Bus is the third reactor water level indicator. This instrument loop is supplied with 125 VOC from the l stationary Battery Rank through the 1C 1 KVA instrument inverter. Recause the IC inverter has no alternate power source, and due to the reactor protection system's one-out-of-three trip logic for reactor water level, the reactor will scram if there is a loss of power or undervoltage signal to the 1C inverter. The licensee proposes to install a static transfer switch to provide an alternate source of 120 VAC power to the inverter. Further, to accomodate anticipated load additions, the licensee proposes to replace the 1KVA inverter with a 5 KVA inverter, and uograde the 125 VDC stationary Rattery Bank's capacity.

2.0 EVALUATION The proposed change would modify paces 13 and 13a of Section 2.6 and page 32m of Section 4.23 of the LACBWR Technical Soecifications relating to the IC Non-Interruotible Bus. Specifically, the licensee proposes to: (1) replace the 1 KVA inverter with a 5 KVA unit, (2) add a static transfer switch to the new inverter, and (3) increase the generator plant battery's capacity from 480 amp-hours to 840 amp-hours.

The new electric configuration would allow the Turbine Ruilding Motor Control Center, a safety-related bus, to deliver power throuah a reserve transformer directly to the IC Non-Interruptible Bus. Such a modification should increase the operational stability of the IC Non-Interruptible Bus by reducing the i frequency of unnecessary scrams due to erroneous water level signals. The L

major safety concern associated with the inverter uparade is that the related battery bank would be able to supply the full amount of power upon demand to its two ma.ior loads: the 5 KVA inverter, including the channel 3 water level indicator, and other DC loads. A fully loaded 5 KVA inverter would require

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315 amp-hours, while the other DC loads would draw 287 amp-hours. Thus, the maximum power demanded of the generator plant battery would be 602 amp-hours.

Because the proposed 840 amo-hour battery bank is creater than the maximum power needed by a fully loaded inverter and other loads, the 1C inverter modification and its concomitant battery bank capacity increase is acceptable. No modifications to the plant generator battery's surveillance j requirements would be necessary. Further, the installation of the static l transfer switch would increase the operational stability of the inverter.

Therefore, the staff finds the proposed IC inverter renlacement and modification acceptable.

3.0 ENVIRONMENTAL CONSIDERATION

This amendment involves a change to a requirement with respect to the installation or use of facility comoonents located within the restricted area as defined in 10 CFR Part 20. The staff has determined that the amendment involves no significant increase in the amounts, and no significant chance in the types, of any effluents that may be released offsite and that there is no significant increase in individual or cumulative occupational radiation exoosure. The Commission has previously issued a proposed finding

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that this amendment involves no significant hazards consideration and there has been no public comment on such findina. Accordingly, this amendment meets the eligibility criteria for cateaorical exclusion set forth in l 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 amendment.

4.0 CONCLUSION

The staff has concluded, based on the considerations discussed above, that:

(1) there is reasonable assurance that the health and safety of the public will not he endangered by oneration in the proposed manner, and (2) such activities will be conducted in compliance with the Commission's reculations and the issuance of this amendment will not be inimical to the common defense and security nor to the health and safety of the public.

Principal Contributor: R. Buck and J. Stang.

Dated: April 14, 1986

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