ML20217P038
| ML20217P038 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 04/06/1998 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20217N997 | List: |
| References | |
| NUDOCS 9804090295 | |
| Download: ML20217P038 (5) | |
Text
I, g esug j, y* & UNITED STATES l
f j f j NUCLEAR REGULATORY COMMISSION WAsMINGToN, D.C. SpeeHooi
...../
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.135' TO FACILITY OPERATING LICENSE NO. NPF-29 i ENTERGY OPERATIONS. INC.
l GRAND GULF NUCLEAR STATION DOCKET NO. 50-416
1.0 INTRODUCTION
l Entergy Operations, Inc., the licensee for the Grand Gulf Nuclear Station (GGNS), by letter dr.ted October 28,19S7, and modified by a letter dated January 9,1998, has requested changes to the l technical specifications (TS) for GGNS to permit implementation of 10 CFR Part 50, Appendix J, l Option B. Some background information and our evaluation of the proposed changes are l provided below.
l The revised technical specification page submitted in the letter of January 9,1998, does not l change the no significant hazards consideration for the proposed change to the TS that was f
noticed in the Federal Reaister on December 3,1997 (62 FR 63976).
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2.0 BACKGROUND
l On September 12,1995, the U.S. Nuclear Regulatory Commissbn (NRC) approved issuance of j a revision to 10 CFR Part 50, Appendix J, " Primary Reactor Coretainment Leakage Testing for
- Water-Cooled Power Reactors" which was subsequently published in the Federal Reaister on l September 26,1995, and became effective on October 26,1995. The NRC added Option B
- Performance-Based Requirements" to allow licensees to voluntarily replace the prescriptive ,
testing requirements of 10 CFR Past 50, Appendix J, with testing requirements based on both overall leakage rate performance and the performance of individual components. The previous :
l rule was retained as Option A.
As part of the development of Option B, the NRC also developed Reguistory Guide (RG) 1.163,
" Performance-Based Containment Leak Test Program," dated Septer iber 1995, to specify a method acceptable to the NRC for complying with Option B. The l'consee has established a 10 CFR Part 50, Appendix J, Testing Program and proposes to add this program to the TS.
However, the licensee proposes to use the guidance of an NRC Safety Evaluation Report (SER) for an exemption from Appendix J granted to GGNS on April 26,1995, rather than the guidance of Regulatory Guide 1.163, as the method of implementing Option B.
Compliance with 10 CFR Part 50, Appendix J, provides assurance that the piimary containment, including those systems and components which penetrate the primary containment, do not 9SO4090295 980406 PDR ADOCK 05000416 P PDR
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exceed the allowable leakage rate specified in the TS and the TS Bases. The allowable leakage rate is determined so that the containment leakage assumed in the safety analyses is not exceeded.
On February 4,1992, the NRC published a notice in the fidt!El Realster (57 FR 4166) discussing a planned initiative to begin eliminating requirements marginal to safety which impose a significant regulatory burden. Appendix J of 10 CFR Part 50 was considered for this initiative and the staff undertook a study of possible changes to this regulation. The study examined the previous performance history of domestic containments and examined the effect on risk of a revision to the requirements of Appendix J. The results of this' study are reported in NUREG-1493, " Performance-Based Leak-Test Program."
Based on the results of this study, the staff developed a performance-based approach to containment leakage rate testing.' On September 12,1995, the NRC approved issuance of this revision to 10 CFR Part 50, Appendix J, which was subsequently published in the Federal Renister on September 26,1995, and became effective on October 26,1995. The revision added Optiv. 5 -Pe;fo,mence-Bawd Rsquirements" to Appendix J to allow licensees to voluntarily replace the prescriptNe teving requirements of Appendix J with testing requirements based on both overall and individual component leakage rate performance.
The NRC staff developed Regulatory Guide 1.163 as a method acceptable to the NRC staff for implementing Option B. This regulatory guide states that the Nuclear Energy Institute (NEI) guidance document NEl 94-01, " Industry Guideline for implementing Performance-Based Option of 10 CFR Part 50, Appendix J" provides methods acceptable to the NRC staff for complying with Option B with four exceptions which are described therein.
Option B requires that the regulatory guide or another implementation document used by a licensee to develop a performance-based leakage rate testing program must be included, by general reference, in the plant TS. The licensee has chosen not to reference RG 1.163 in the GGNS TS. Instead, the licensee has proposed to revise the technical specifications to reference the NRC staff SER that was the basis for an easiler exemption from Appendix J granted to GGNS. The licensee proposed this exemption by letter dated August 13,1993, and supplemented the request by letters dated April 15, May 11, June 24, July 20,1994 and April 18, ,
1995. The exemption (from what is now Option A to Appendix J) was approved by the NRC staff l by letter dated April 26,1995. The exemption request proposed a program similar to Appendix J,-
Option B, in that it allowed primary containment leakage rate testing intervals to be based on performance of the systems, structures and components involved. The test methods and criteria for containment leakage rate testing used by the licensee were not affected by this exemption.
The technical basis and the technical specifications changes proposed in the Grand Gulf.
exemption were used by the NRC staff, along with the staff's own studies, in the development of i Appendix J, Option B. This exemption expires following startup following Refueling Outage 9 I (scheduled for Spring 1998).
Regulatory Guide 1.163 specifies an extension in Type A test frequency to at least one Type A test in 10 years based upon two consecutive successful tests. Type B tests may be extended up to a maximum interval of 10 years based upon completion of two consecutive successful tests l and Type C tests may be extended up to 5 years based on two consecutive successful tests. ,
Differences between Regulatory Guide 1.163 and the Grand Gulf exemption arte discussed in the l Evaluation section of this safety evaluation.
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By letter dated October 20,1995,' NEl proposed TS to implement Option B. After some discussion, the staff and NEl agreed on final TS which were attached to a letter from C. Grimes (NRC) to D. Modeon (NEI), dated November 2,1995. These TS are to serve as a model for
' licensees to develop plant specific TS implementing Option B. The licensee has generally followed this guidance.
For a licensee to determine the performance of each component, factors that are indicative of or affect performance, such as an administrative leakage limit, must be established. The administrative limit is selected to be indicative of the potential onset of component degradation.
Although these limits are subject to NRC inspection to assure that they are selected in a reasonable manner, they are not TS requirements. Failure to meet an administrative limit
- requires the licensee to retum to the minimum value of the test interval.
Option B requires that the licensee maintain records to show that the criteria for Type A, B and C tests have been met. In addition, the licensee must maintain comparisons of the performance of the overall containment system and the individual components to show that the test intervals are adequate. These records are subject to NRC inspection.
3.0 EVALUATIOh[
- The licensee's October 28,1997, letter to the NRC proposed to establish a "10 CFR Part 50, Appendix J, Testing Program" and add this program to the TS. The program references the NRC staff's safety evaluation on the licensee's exemption to Appendix J, dated April 26,1995, as a method acceptable to the NRC for complying with Option B. This requires * -5ange to existing TS 3.6.1.1.1, 3.6.1.2.1, 3.6.1.3.5, 3.6.1.3.8, 3.6.1.3.9, and the addition of the "10 CFR Part 50, Appendix J, Testing Program" as TS Section 5.5.12. Corresponding sections of the TS Bases were also modified.
Option B permits a licensee to choose: (1) Type A; or (2) Types B and C; or (3) Types A, B, and C testing to be done on a performance basis. The licensee has elected to perform Type A, B and C testing on a performance basis.
There are some differences between Regulatory Guide 1.163 (and the document it endorses, NEl 94-01) and tne April 26,1995, exemption to Appendix J and the associated SER. The licensee discussed several of these differences in its October 28,1997 submittal. These are discussed further below.
The NRC staff's April 26,1995, SER limited the test intervals for Types B and C testing to 5
- years. The licensee has proposed to extend the Type B test interval to 10 years and to keep the
' Type C interval at its present value of 5 years. This is consistent with Regulatory Guide 1.163 and is acceptable.
The licensee has removed the Note from the TS stating that surveillance requirement (SR) 3.0.2 is not applicable. SR 3.0.2 states, in part,'
The specified frequency for each SR is met if the Surveillance is performed within 1.25 times the interval specified in the Frequency...
The April 26,1995, SER does not address extending the surveillance interval, since the licensee did not propose ac wemption from these requirements. The staff does not consider it 1
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4 appropriate to extend 10 year intervals, such as those permitted by Option B for Types A and B tests by the 25% specified in SR 3.0.2. After discussions with the licensee, the licensee agreed to limit the extension of the test interval to be consistent with the guidance in NEl 94-01 (endorsed by Regulatory Guide 1.163). NEl 94-01 limits any extension to the test interval for Tyre A tests to 15 months. NEl 94-01 states that Types B and C test intervals may be extended up to 25% of the test interval, not to exceed 15 months. For Type A tests, an extension may be used only in cases where refueling outages have been changed to accommodate other factors.
The licensee's October 28,1997, letter riso discusses the use of altemative testing or analysis in lieu of as-found tests when maintenance is performed. As the licensee points out, Regulatory Guide 1.163 does not endorse the use of attemative testing or analysis in lieu of as-found testing.
The licensee agrees with this position but states that it is the current practice at GGNS to use Valve Operation Test and Evaluation System (VOTES) testing in lieu of a local leakage rate test (LLRT) for maintenance that does not affect leak-tightness, which the licensed defines as maintenance that affects only the valve actuator. The licensee states that an LLRT would only
- be performed if the VOTES test detected a degraded thrust value which could indicate seat leakage. This position is consistent with the intent of Appendix J, Option B and is acceptable.
l According to the licensee's earlier exemption request, a Type B or C test would be performed j following maintenance or modification of a component that could affect the component's leak-tightness. The licensee had proposed (and later adopted) the criterion that if the post-work Type B or C test leakage rate for extended intervals was not greater than 5% of the Type B or C test ,
leakage rate performed prior to the maintenance or modification, and other applicable retests l were acceptable, re-establishment of component performance was not required and the component may remain on its current test interval. The licensee stated in the October 28,1997, letter that this criterion has been removed under 10 CFR 50.59. The staff finds this change could be made because the 5% criterion is not an Option B requirement.
The intervals for leakage rate testing of the primary containment air locks specified in NEl 94-01 i are different in some respects from those specified in the licensee's exemption of April 26,1995, and the current proposal. NEl 94-01 states that air locks shall be tested at a frequency of once per 24 months. The licensee's proposalis the same. However, NEl 94-01 also states that for periods of multiple entries where the air lock doors are routinely used for access more frequently
- than once every 7 days, door seals may be tested once per 30 days during this time period. ,
When containment integrity is required, air lock door seals should be tested within 7 days after l each containment access. T he licensee's proposal is that following opening of an air lock door when containment integrity is required, the air locks shall be tested at least every 30 days. The ;
30 day test requirement may be satisfied by testing the air lock door seals. We find the !
licensee's proposal to be acceptable, since the differences between the licensee's proposal and J the testing mandated by NEl 94-01 are not significant. l i
NEl 94-01 states that failure of an air lock door leakage rate test requires a cause determination and corrective actions (unspecified). The licensee's proposal specifies more frequent leakage rate testing of the failed air lock door following a failure of an air lock test, until two consecutive ;
tests have been successful. We find this proposed corrective action to be acceptable. i Based on the above, the licensee's proposal to perform primary containment leakage rate testing ,
under the requirements of 10 CFR Part 50, Appendix J, Option B, is acceptable. The licensee's )
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proposal to implement Option B in accordance with the April 26,1995, exemption and staff SER relating to Appendix J, Option A, as modified by the licensee's revised TS page attached to l the January 9,1998, letter, is also acceptable. The staff has determined that.the use of the l guidance of the April 26,1995, SER is consistent with the intent of Regulatory Guide 1.163 and is therefore acceptable. The technical specifications implementing Option B for the Grand Gulf Nuclear Station, as modified by the revised TS page attached to the licensee's January 9,1998, letter, are also acceptable.
4.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Mississippi State offm' ial was notified of the proposed issuance of the amendment. The State official had no comments.
5.0 ENVIRONMENTAL CONSIDERATION
.The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes surveillance requirements. The NRC staff has determined that the amendment involves no significant incmase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public -
comment on such finding (62 FR 63976). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b),
no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
6.0 CONCLUSION
S The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in tne proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the hesith and safety of the public.
Principal Contributors: R. Lobel J. Donohew Date: _ April 6, 1998
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