NL-17-1366, Proposed Alternative RR-V-11 Regarding Main Steam Safety Relief Valve Testing Requirements
| ML17215A558 | |
| Person / Time | |
|---|---|
| Site: | Hatch  |
| Issue date: | 08/03/2017 |
| From: | Hutto J Southern Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NL-17-1366 | |
| Download: ML17215A558 (4) | |
Text
~ Southern Nuclear AUG 0 3 2017 Docket Nos.: 50-366 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 J. J. Hutto Regulatory Affairs Director Edwin I. Hatch Nuclear Plant-Unit 2 Proposed Alternative RR-V-11 40 lmclllL"' *' Cemcr Pu r~""Y Poq OfliLc Hox 1295 fl1rnunglwn. AI 1~2-12 205 991 ~xn 1el 205 99271i01 f,l'\\
NL-17-1366 Regarding Main Steam Safety Relief Valve Testing Requirements Ladies and Gentlemen:
In accordance with 10 CFR 50.55a(z)(2), Southern Nuclear Operating Company (SNC) hereby submits Alternative RR-V-11 to allow a one-time extension of the main steam safety relief valve (SRV) main body test frequency requirements for Edwin I. Hatch Nuclear Plant (HNP) Unit 2.
This letter contains no NRC commitments. If you have any questions, please contact Ken McElroy at 205.992.7369.
Respectfully submitted, J.J. Hutto Regulatory Affairs Director JJH/RMJ
Enclosure:
HNP Alternative RR-V-11 Cc:
Regional Administrator, Region II NRR Project Manager-Hatch Senior Resident Inspector-Hatch RTYPE: CHA02.004
Edwin I. Hatch Nuclear Plant - Unit 2 Proposed Alternative RR-V-11 Regarding Main Steam Safety Relief Valve Testing Requirements Enclosure HNP Alternative RR-V-11
Enclosure to NL-17-1366 HNP Alternative RR-V-11
- 1. References ASME Code Component(s) Affected Code Class:
ASME Section XI Code Class 1 Component Numbers:
Various (see Table 1 for detailed list of components)
Code
References:
ASME OM Code, 2004 Edition thru 2006 Addenda
- 2. Requested Approval Date Approval is requested by May 1, 2018.
- 3. Applicable ASME Code Requirements ASME OM Code, 2004 Edition through the 2006 Addenda, Division 1, Mandatory Appendix I, lnservice Testing of Pressure Relief Devices in Light-Water Reactor Nuclear Power Plants, Section 1-1320 requires that all Class 1 pressure relief valves shall be tested at last once every 5 years. Additionally, a minimum of 20% of the valves from each valve group shall be tested within any 24-month period.
The Target Rock Model 0867F 3-Stage Main Steam Safety Relief Valves (SRVs) subject to this request are listed below in Table 1. This table applies to Hatch Nuclear Plant (HNP)
Unit 2 only.
- 4. Components Affected TABLE 1 Valve Description ASME Class 2B21-F013A Main Steam SRV 1
5. Reason for Request
All HNP Unit 2 SRV main valve bodies were replaced with pre-tested components during a forced outage in May 2016. This replacement was required to address Part 21 Report, Notification of a Defect, Potential for Test Induced Damage, 0867F Series Main Steam Safety Relief Valves. No SRV main bodies were replaced with pre-tested valves during the Unit 2 February 2017 refueling outage. The next opportunity to replace the Unit 2 SRV main E-1
Enclosure to NL-17-1366 HNP Alternative RR-V-11 bodies during a scheduled refueling outage will be in February 2019. This will result in the SRV main body test frequency exceeding the 20% in 24-month requirement by less than one year.
100% of the SRV pilot valves were replaced with pre-tested valves in the February 2017 refueling outage, so they will continue to meet all ASME OM Code test requirements.
Pursuant to 10 CFR 50.55a, "Codes and Standards," paragraph (z)(2}, relief is requested from the frequency specifications of the ASME OM Code. The basis for this relief request is the Code requirement presents an undue hardship without a compensating increase in the level of quality or safety.
6. Proposed Alternative and Basis for Use
Proposed Alternative and Basis SNC requests approval for a one-time extension of the SRV main valve body code surveillance from the 20% test frequency. The SRV main body and pilot valves will continue to meet the 1 00% 5-year test frequency requirement.
This relief request is for a short duration. During any 24-month period, the OM Code requires a minimum of 20% (3 of 11) SRV main bodies to be tested. HNP relief request RR-V-8 allows the specified time between surveillances to be extended by up to 25% (6 months) resulting in a 30-month maximum time between tests. This relief request will extend the maximum time between surveillances by approximately 4 months.
Meeting the OM Code 20% test minimum requirement would result in 6 SRV main valve bodies being tested during the time frame in question. HNP Unit 2 replaced all 11 (1 00%} of their SRV main bodies in May 2016. During the spring 2019 Unit 2 refueling outage, HNP is scheduled to replace 6 SRV main bodies.
100% of the SRV pilot valves were replaced with pre-tested valves in February 2017. HNP Unit 2 is scheduled to replace 100% of the SRV pilot valves during the February 2019 refueling outage. This testing frequency far exceeds the OM Code requirements.
The 0867F 3-stage SRVs were initially installed during the spring 2011 Unit 2 refueling outage, and have experienced no operational failures.
Conclusions Based on the determination that compliance with the ASME OM Codes requirement results in a hardship without a compensating increase in the level of quality or safety, this proposed alternative should be granted.
7. Duration of Proposed Alternative
This proposed alternative is a one-time extension of the OM Code requirement to test 20%
of the HNP Unit 2 SRVs every 24 months. The duration of this request is approximately 34 months (April, 2016-February, 2019).
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