ML19345H191
| ML19345H191 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 04/16/1981 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19345H187 | List: |
| References | |
| NUDOCS 8105010191 | |
| Download: ML19345H191 (3) | |
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 58 TO FACILITY OPERATING LICENSE NO. NPF-1 PORTLAND GENERAL ELECTRIC COMPANY THE CITY OF EUGENE, OREGON PACIFIC POWER AND LIGHT COMPANY TROJAN NUCLEAR PLANT 00CXET NO. 50-344 Introduction By letter dated December 28, 1979 as supplemented June 19, 1980 and March 23, 1981, Portland General Electric Company, et al. (the licensee), requested changes tn the Technical Specifications appended to Facility Operating License No. NPF-1 for operation of the Trojan Nuclear Plant in Columbia County, Oregon. The proposed changes would (1) clarify the testing require-ment for the diesel fuel transfer pumps and (2) revise the volume of borated water required to be available in the cold shutdown and refueling modes.
Discussion and Evaluation 1.
Testing Diesel Fuel Transfer Pumos The present Technical Specifications require the licensee to verify that each fuel transfer pump transfers fuel from each fuel storage tank to tne day tank of each diesel via the installeo cross-connection IInes.
This wording is not correct for the approved design at Trojan. The Trojan design has two diesel fuel tanks and two diesel fuel transfer Each tank has an associated transfer pump, with no cross-connection pumps.
provided to tre other tank. Downstream of each pump there is a cross-connection so that each tansfer pump can supply fuel to either day tank.
It is not possible, however, for each tansfer pump to take fuel from either tank.
It can only take fuel from its associated tank.
The licensee proposes to clarify this Technicrl Specification so that the requirement matches the NRC-approved design. The proposed change would require the licensee to verify that each fuel transfer cump transfers fuel from its associated fuel storage tank to the day tank of each diesel via tne installed cross-connection lines.
The proposed revised wording corrects the existing error and is there-fore acceptable.
8105010lCiI
. 2.
Soric Acio crorage - Cold Shutdown and Refuelino t4 odes The present Technical Specifications require that 14,418 gallons of borated water (7000 ppm boron) in one boric acid tank (8AT) or 143,374 gallons of horated water (2000 ppm bcron) in the refueling water storage tank (RWST) be available in the cold shutdown and refueling operational modes. The purpose of this specification is to ensure that borated water sources, sufficient in volume and bcron concentrations, are available at all times while in these modes to be able to add 1%
negative reactivity to the reactor should it be needed due to inadvertent loss of required shutdown margin.
The most limiting condition with respect to the amount of borated water needed to meet this requirement occurs in the refueling mode when the reactor cavity is flooded to just below the containment operating deck (accroximately el. 91 feet).
The licensee has reassessed the amounts of borated water needed in both the BAT and RWST and has found that the present specifications, which were issued when the original operating license was issued in November 1975, are more than sufficient to meet the negative reactivity require-ment.
The licensee calculates that 8494 useable gallons of BAT water are needed. This volume, however, must be increased by 4050 gal. became the minimum instrument liquid volume is about 4050 gal., and it would be undesirable to fall below the instrument range while pumping barated water from the tank. Therefore, 12,544 gallons of BAT water are required (rounded upward to 12,600 gallons).
AS for RWST, 23,432 gal. are actually needed. Here again, however, this volume must be increased because 78,000 gallons of RWST water are unusable due to tank geometry. Therefore, a total of 101,432 gallons of RWST are required (rounded upward to 102,000 gallons).
We have independently verified the licensees calculations and agree l
with the results. These volumes and baron concentrations constitute l
borated water sources sufficient to meet the negative reactivity requirements in these modes. Since the refueling mode is by far the limiting case, these amounts are more than sufficient to offset po'sitive reactivity effects caused by reactor cooldown from 200 F to the refueling 0
mode temperature (1400F), and meet the 1% negative reactivity capability in Mode 5 (cold shutdown) when reactor coolant volume is much less than the effective volume in the refueling mode.
Based on the foregoing, we find the proposed revision to the requirements for borated water sources in the cold shutdown and refueling modes l
acceptable, f
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3-Environmental Consideration We have determined that the amendment does not authorize a change in effluent types or total amounts nor an increase in power level and will not result in any significant environmental impact. Having made this determination, we have further concluded that the amendment involves an action which is insignificant from the standpoint of environmental imoact and, pursuant to 10 CFR 551.5(d)(4), that an environmental impact statement or negative declaration and environ-mental impact appraisal need not be prepared in connection with the issuance of this amendment.
Conclusion We have concluded, based on the considerations discussed above, that:
(1) because the amendment does not involve a significant increase in the probability or consequences of accidents previously considered and does not involve a significant decrease in a safety margin, the amendment does not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) such activities will be conducted in compliance with the Commission'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.
Date: April 16, 1981 r
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