ML20052F830
| ML20052F830 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 05/06/1982 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20052F829 | List: |
| References | |
| NUDOCS 8205140013 | |
| Download: ML20052F830 (3) | |
Text
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,t WASHINGTON, D. C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENTS NO. 40 AND NO. 24 TO FACILITY OPERATING LICENSE NOS. NPF-4 AND NPF-7 VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION, UNITS NO. 1 AND NO. 2 00CKET NOS. 50-338 AND 50-339
==
Introduction:==
By letter dated April 16, 1982 (Serial No. 228), the Virginia Electric and Power Company (the licensee) requested a change to Operating Licenses NPF-4 and NPF-7 for the North Anna Power Station, Units Nos. 1 and 2 (NA-1&2). The licensee's requested change would revise the Technical Specifications (TS) to provide relief from the testing requirements for large snubbers greater than 50,000 inch-pounds (50 kips) around the steam generators and reactor coolant pumps. The relief would apply to the NA-2 current refueling outage and the forthcoming NA-1 refueling outage only.
A discussion of these matters and our evaluation.and conclusions regarding the licensee's requested relief follows.
Discussion:
The NA-1&2 TS 3/4.7.10 states'that "At least once per 18 months during shutdown, a representative sample of that number of snubbers which follows the expression 35 (1+C/2), where C=2 is the allowable number of snubbers not meeting the acceptance criteria selected by the operator, shall be functionally tested either in place or in a bench test." The TSs also stated that "at least 25% of the snubbers in the representative sample
.I -
shall include snubbers within 5 feet of heavy equipment." The 10 and 14 inch snubbers (3reater than 50 kips) around the steam generators and
~T reactor-coolant p'Omps are included in this representative sample.
The licensee states that functionally testing large snubbers greater than 50 kips, around the steam generators and reactor coolant pumps, would create a personnel radiation exposure problem.
The radiation exposure rate at the steam generator snubber supports is approximately 25 mili-Roentgens-per hour (mR/hr) and for the reactor coolant pump snubber supports is approximately 150 mR/hr.
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The licensee further states that for snubbers greater than 50 kips there are no valve adjustments to control the bleed rates as found on small snubbers. The larger snubbers have orfice plates and there is no dr~ift during power operation. The seals on the larger snubbers are qualified for 10 years and the seals are visually inspected at each refueling outage.
The licensee has requested that relief be granted from the functional testing of large snubbers (greater than 50 kips) around steam generators
'and reactor coolant pumps for the present NA-2 Cycle 1 refueling outage and the forthcoming NA-1 Cycle 3 refueling outage. The licensee states that the relief will prevent radiation exposure to personnel and is con-sistent with the As-Low-As-Reasonably Achievable (ALARA) concept.
Also, the licensee has stated that it will hereafter functionally test a representative sample of large snubbers greater than 50 kips at each refueling outage. Finally, the licensee indicated that in-place testing techniques are being investigated for the testing of snubbers greater than 50 kips. Also, the testing of the large snubbers will take place on an integrated basis within the ten year seal lifetime of the large snubbers.
Evaluation:
Previous methods for testing snubbers resulted in damage to many snubbers due to the test removable and installation pr wess. This. defeated the purpose for conducting tests. Also, in the past the testing of snubbers was limited to a rated capacity less than 50 kips.
Based in part on the above, the NRC generic letter dated November 20, 1980, requested that all operating facilities adopt newly revised TS regarding snubbers surveillance. These revised NRC TS for snubbers were incorporated in the NA-1&2 TS per Amendments Nos. 33 and 13 to Operating Licenses No.
NPF-4 and No. NPF-7 on November 5, 1981.
The staff realized that the newly revised NRC TS for snubbers would lead to personnel r.adiation exposures when testing certain snubbers greater than 50 kips. Therefore, the newly revised TS included specific provisions for licensee's to request relief from functional testing of snubbers greater than 50 kips and to allow for a reasonable period of time to implement the new and in some cases plant specific in-place. test methods for large n.
It is noted that in-place test methods should minimize personnel exposure rates resulting from the functional test requirements for snubbers.
Not withstanding the above, the newly revised snubber TS also specifically stated that relief would be granted only if a justifiable basis for the relief was presented by the licensee and that snubber operability could be justified.
. The licensee's request for relief meets the required conditions as specified in the NA-1&2 TS.
In addition, the licensee has stated that it will function-ally test a representative sample of large snubbers greater than 50 kips for each refueling outage hereafter. Required testing of these snubbers will commence at the next refueling outage and, for the large snubbers in question, be completed on an integrated bases within the ten year seal lifetime. The required testing will either be by in-place testing niethods presently being investigated by the licensee or by available bench test methods already in use.
Based on the above, we find the licensee's request for relief to be acceptable. The relief, as hereby granted, applies only to the NA-1&2 large snubbers greater than 50,000 kips around the steam generators and reactor coolant pumps. Also, the relief as granted applies only to the NA-1 Cycle 3 refueling outage and the NA-2 Cycle 1 refueling outage.
Environmental Consideration We have determined that the amendments do 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 amendments involve an action which is insignificant from the standpoint of environmental impact 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 these amendments.
Conclusion We have concluded, based on the considerations discussed above, that:
(1) because the amendments do not involve a significant increase in the probability or consequences of accidents previously considered and do not involve a significant decrease in a safety margin, the amendments do 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 r
regul-ations and the issuance of these amendments will not be inimical-to the common defense and security or to the health and safety of the public.
Date: fiay 6, 1922
. Principal Contributors:
H. Shaw L. Engle
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