ML20057A255
| ML20057A255 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 08/30/1993 |
| From: | Varga S Office of Nuclear Reactor Regulation |
| To: | PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| Shared Package | |
| ML20057A256 | List: |
| References | |
| NUDOCS 9309130286 | |
| Download: ML20057A255 (7) | |
Text
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7590-01 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION In the Matter of
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PHILADELPHIA ELECTRIC COMPANY
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PUBLIC SERVICE ELECTRIC AND GAS COMPANY
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Docket No. 50-278 DELMARVA POWER AND LIGHT COMPANY
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ATLANTIC CITY ELECTRIC COMPANY
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(Peach Bottom Atomic Power Station, Unit 3)
EXEMPTION I.
The Philadelphia Electric Company, et al. (PEco, the licensee), is the holder of Operating License No. DPR-56, which authorizes operation of the Peach Bottom Atomic Power Station, Unit 3, at steady state reactor core power levels not in excess of 3293 megawatts thermal. The license provides, among other things, that the licensee is subject to the rules, regulations and orders of the Commission now or hereafter in effect.
The plant is a boiling water reactor located at the licensee's site in York County, Pennsylvania.
II.
Section 50.54(o) of 10 CFR Part 50 requires that primary reactor containments for water cooled power reactors be subject to the requirements of Appendix J to 10 CFR Part 50. Appendix J contains the leakage test re7uirements, schedules, and acceptance criteria for tests of the leak tight integrity of the primary reactor containment and systems and components which penetrate the containment.
9309130286 930830 PDR ADOCK 05000278 P
.Section III.D.2(a) of Appendix J to 10 CFR Part 50 requires that Type B leak rate tests, exce;t for air locks, be performed during reactor shutdown for refueling, or other convenient intervals, but in no case at intervals greater than 2 years. Type B tests are intended to detect local leaks and to measure leakage across each pressure-containing or leakage-limiting boundary for certain reactor containment penetrations.
Section III.D.3 of Appendix J to 10 CFR Part 50 requires that Type C leak rate tests be performed during each reactor shutdown for refueling but in no case at intervals greater than 2 years.
Type C tests are intended -to measure containment isolation valve leakage rates for certain containment isolation valves.
III.
By letter dated June 11, 1993, and supplemented by letter dated July 26, 1993, the licensee requested a one-time exemption from the requirements of Appendix J, Sections III.D.2(a) and III.D.3 for a period of 60 days for the isolation valves or leakage boundaries for 46 penetrations.
In their request, the licensee provided a list of the affected penetrations and associated plant-specific leak test procedures, the date when the leak tests had last been performed and the date when the current leak test will expire.
The licensee has implemented a 24-month operating cycle schedule at the Peach Bottom facility. The last refueling outage for Unit 3, 3R08, commenced in September 1991 and ended in December 1991 and the next refueling outage, 3R09 is scheduled to commence no later than September 18, 1993. The leak tests for which the licensee has requested schedular exemption were last
. conducted during refueling outage 3R08, based on the information provided in the licensee's application. The licensee has stated that the affected leak tests require either that safety systems be isolated or require access to the drywell, either of which would require the reactor to be shutdown.
The licensee has divided the affected leak tests into two categories:
- 1) those that require shutdown reactor conditions but fall due prior to the scheduled commencement of 3R09 on September 18, 1993, and 2) those that require reactor shutdown conditions and fall due after the scheduled commencement of 3R09. There are 11 leak test surveillance procedures.
affecting 12 penetrations in the first category. These tests and penetrations are listed in Table 1 of the licensee's June 11, 1993 request.
The earliest of these tests falls due on September 15, 1993, 4 days prior to the scheduled shutdown. The licensee has requested an exemption for 60 days which will allow the unit to operate until the beginning of the planned outage without shutting down to perform leak tests and which will allow for flexibility in planning the leak tests during the outage.
There are 28 leak test surveillance procedures affecting 36 penetrations in the second category described previously. These tests are listed in Table 2 of the licensee's June 11, 1993, submittal, and supplemented by the July 26, 1993, letter. The licensee has requested an exemption of 60 days to allow for flexibility in planning these leak tests during the outage. The licensee stated that all of the affected penetrations will be leak tested prior to restart from 3R09.
I
. IV.
The licensee presented information in support of their request for a 60-day extension of the Type B and C test intervals. The maximum allowable leakage rate for maintaining primary containment (L, - minimum pathway leakage) is 125,417 cc/ min. The as-found total Type B and C minimum pathway.
leakage rate cbserved during Unit 3 refueling outage 3R08 during the fall of 1991 was 35,197 cc/ min. The as-left leak rate for that same outage was 24,453 cc/ min.
PEco stated that an extension of the leak test interval to allow for 4 days of operation is not likely to decrease the margin between as-found leak I
rates and L,.
PEco also stated that the remainder of the total 60-day extension, requested for outage planning ficxibility, will have minimal safety 4
significance since the unit will be in cold shutdown.
Primary containment integrity is not required during cold shutdown.
V.
Based on the above, the staff finds there is reasonable assurance that the containment leakage-limiting function will be maintained and that a forced outage to perform Type B and C tests is not necessary. Therefore, the staff finds the requested temporary exemption, to allow the Type B and C test intervals for the penetrations listed in the licensee's June 11, 1993 request, and supplemented by letter dated July 26, 1993, to be extended for 60 days from their current expiration date, to be acceptable. The exemption request has been evaluated in a safety evaluation dated August 30, 1993
. Accordingly, the Commission has determined that, pursuant to 10 CFR Part 50.12(a), the requested exemption is authorized by law, will not present an undue risk to public health and safety, and is consistent with the common defense and security. The Commission finds that the special circumstances as required by 10 CFR Part 50.12(a)(2) are present. As specified in 50.12(a)(2)(ii), special circumstances are present whenever the application of the regulation in the particular circumstance would not serve the underlying purpose of the rule or is not necessary to achieve the underlying purpose of the rule. The underlying purpose of the rule is to ensure that the components comprising the primary containment boundary are maintained and leak tested at periodic and appropriate intervals. The 24-month maximum interval was originally expected to bound the typical operating cycle, including a limited amount of mid-cycle outage time. The advent of advanced fael tynes has made it possible to operate the facility for 24-months with minimal, if any, mid-cycle outage time.
Strict adherence to the 24-month maximum interval is not necessary to meet the underlying purpose of the rule in that, taking into consideration the sixty day extension, the components that comprise the primary cont 6;nment boundary will still be tested at a frequency that is appropriate to those components and their application.
In addition, the 60-day extension represents a minimal increase in the existing 24-month interval required by the rule. Therefore, the staff finds the requested temporary exemption, to allow the Type B and C test intervals for penetrations described in the licensee's June 11, 1993 and July 26, 1993 letters, to be extended for 60 days, to be acceptable.
. An exemption is hereby granted from the requirements of Sections III.D.2(a) and III.D.3 of Appendix J to 10 CFR Part 50, which requires that Type B and C tests be performed during each reactor shutdown for refueling but in no case at intervals greater than 2 years, for a period of 60 days from the expiration of the current leak test for the affected penetrations.
Pursuant to 10 CFR 51.32, the Commission has determined that the granting of this Exemption will have no significant impact on the quality of the human environment (58 FR 45536).
This exemption is effective upon issuance.
FOR THE NUCLEAR REGULATORY COMMISSION l
Original signed by:
Steven A. Varga, Director Division of Reactor Projects - I/II Office of Nuclear reactor Regulation Dated at Rockville, Maryland this30thday of August, 1993
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. An exemption is hereby granted from the requirements of Sections III.D.2(a) and III.D.3 of Appendix J to 10 CFR Part 50, which requires that Type B and C tests be performed during each reactor shutdown for refueling but in no case at intervals greater than 2 years, for a period of 60 days from the expiration of the current leak test for the affected penetrations.
Pursuant to 10 CFR 51.32, the Commission has determined that the granting of this Exemption will have no significant impact on the quality of the human environment (58 FR 45536).
This exemption is effective upon issuance.
FOR THE NUCLEAR REGULATORY COMMISSION f
W r
even. Varga, irect Division of Reactor Proje ts - I/II Office of Nuclear reactor Regulation Dated at Rockville, Maryland this30thday of August, 1993