ML20138D258

Safety Evaluation Authorizing Licensee Proposed Alternative to Use 1989 Edition of ASME Boiler & Pressure Vessel Code,Section XI for Performance of Containment Repair & Replacement Activities Until 970909

ML20138D258
Person / Time
Site:	Sequoyah
Issue date:	04/28/1997
From:	NRC (Affiliation Not Assigned)
To:
Shared Package
ML20138D245	List: ML20138D241 ML20138D258
References
NUDOCS 9705010075
Download: ML20138D258 (2)

Text

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p tr p h UNITED STATES

. # B NUCLEAR RE2ULATORY COMMI SION i

f WASHINGTON, D.C. 20066 4001 le \, /

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF RE0 VEST FOR THE IMPLEMENTATION OF 10 CFR 50.55a RE0VIREMENTS RELATED TO REPAIR AND REPLACEMENT ACTIVITIES FOR CONTAINMENT TENNESSEE VALLEY AUTHORITY SE0U0YAH NUCLEAR PLANT. UNITS 1 AND 2 l

DOCKET NOS. 50-327 AND 50-328 INTRODUCTION In Federal Register Notice No. 154, Volume 61, dated August 8, 1996, the Nuclear Regulatory Commission amended its regulations to incorporate, by reference, the 1992 Edition of Subsections IWE and IWL of Section XI of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel l Code (the Code)into 10 CFR 50.55a, " Code and Standards." Specifically, 10 CFR 50.55a(b)(2) and 10 CFR 50.55a(g)(6)(ii)(B) were added to the regulations. These Code subsections provide the requirements for inservice inspection (ISI) of Class CC (concrete) and Class MC (metallic) containments of light-water reactors. The effective date of the amended rule was September 9, 1996, and has accelerated implementation provisions such that l licensees are to incorporate the requirements into their ISI program and complete the first containment inspection within five years of the effective date. In addition, any repair or replacement activity to be performed after the effective date must be in accordance with the respective requirements of Subsection IWE or IWL. However, a licensee may submit a request for relief from the implementation date of the amended rule.

• Alternatives to Code requirements may be used by nuclear licensees when authorized by the Commission if the proposed alternatives to the requirements are shown to provide an acceptable level of quality and safety (10 CFR 50.55a(a)(3)(1)), or if compliance with the Code requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety [10 CFR 50.55a(a)(3)(ii)].

EVALUATION The Tennessee Valley Authority (TVA, the licensee), in a letter dated l February 10, 1997, citing hardship and/or difficulty without a compensating l increase in quality or safety above that provided by current programs, requested relief for its Sequoyah Nuclear Plant from the implementation date ENCLOSURE t

9705010075 970428 PDR ADOCK 05000327 P PDR

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of the amended 10 CFR 50.55a until September 7, 1997. The licensee plans to make improvements to several containment penetrations during a Unit I scheduled refueling outage beginning March 22, 1997. Given the accelerated implementation schedule of the rule and the immediate effective date for repair and replacement activities, the immediate implementation of repair and replacement requirements would demand licensee action in a short period of time. This would result in hardship and/or difficulty without an increase in quality or safety above current programs.

There are no known safety concerns with the containments of Sequoyah Units 1 and 2 which would compromise their ability to perform their intended safety functions. All improvements are to be performed in accordance with the scope of the current containment ISI and repair and replacement program, which is based on the 1989 Edition of the ASME Code. The licensee has developed an interim quality assurance program which includes provisions for repair and replacement, inspection, materials procurement, maintent.nce, documentation, and reporting to be utilized until September 9, 1997. The interim program will provide a sufficient level of containment integrity during the period of relief between September 9, 1996 and September 9, 1997.

CONCLUSION Based on the review of the licensee's relief request, the staff agrees with the licensee that the inediate implementation of the requirements of the 1992 Edition of the ASME Code for repair and replacement activities, as required by 10 CFR 50.55a, will result in hardship for the licensee without a compensating increase in the level of quality and safety. Use of the 1989 Edition of the ASME Code and the associated quality assurance requirements, as supplemented by the site specific quality assurance program developed by the licensee, provides adequate assurance of containment integrity for the period requested.

l Accordingly, the licensee's relief request for dela,.J implementation of 10 CFR 50.55a is authorized, pursuant to 10 CFR 50.5Sa(a)(3)(ii), until September 9, 1997.

Principal Contributor: Thomas Cerovski Date: April 28, 1997 l