ML20024H707

Forwards Integrated Safety Assessment Program,Executive Summary, Initial Rept.Updates Will Be Submitted Approx Every 6 Months

ML20024H707
Person / Time
Site:	Millstone
Issue date:	05/31/1991
From:	Mroczka E, Romberg W NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20024H708	List: ML20024H707 ML20024H709
References
B13436, NUDOCS 9106100275
Download: ML20024H707 (5)

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H ARTFORD. CONNECTICUT 06141-0270 k k J I C3%lMCO [ (203) 665-5000 May 31, 1991 Docket No d 0_421 B13436 Re: ISAP U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 2R55 Gentlemen:

Millstone Nuclear Power Station, Unit No. 3 Integrated Safety Assessment Program initial Sut.mittal Report During the past several years, Northeast Nuclear Energy Company (NNECO),

Connecticut Yankee Atomic Power Company (CYAPCO), and the NRC have been devel-oping and implementing the Integrated Safety Assessment Program (ISAP) at Millstone Unit No. I and the Haddam Neck Plant. Our experience to date with ISAP has demonstrated the program to be a resource efficient and cost-effective process for enhancing nuclear power plant safety and operation. We are firmly committed to continued participation in the ISAP at these units.

In addition, this submittal supports our previous commitment to expand partic-ipation in the ISAP to Millstone Unit No. 3.

We believe that the ISAP has been and continues to be very beneficial to both NNECO and the NRC. The NRC Staff has extended various opportunities to licensees to take advantage of integrated assessment type methodologies.

Beyond the ISAP pilot program, the Staff issued Generic letter (GL) 88-02, Integrated Safety Assessment Program II, as a derivitive of ISAP, to again ascertain utility interest on participating in the program. Later, during the course of the Individual Plant Examination (IPE) for Severe Accident Vulnera-bilities, the Staff reintroduced the integrated assessment concept, in GL 88-20 and NUREG-1335, as a means for scneduling the potentially resulting modifications. Most recently, the Staff response to licensees on the Regula-tory impacts Survey identified several issues, which the Staff proposed to address. The first being "the Cumulative Effect of [NRC) Requirements" and a recognition of the need for a means to evaluate and schedule the Staff generic issues. The Integrated Regul atory Requirements Implementation Schedule (IRRIS) is a new version of an ISAP-like integrated assessment and scheduling process. Since we consider IRRIS and ISAP as conceptionally similar, we view the new IRRIS proposal as an affirmation of our ISAP experience.

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U.S. Nuclear Regulatory Commission B13436/Page 2 May 31, 1991 As part of our experience with ISAP, NNEC0 and CYAPC0 have developed, in conjunction with the NRC, a sophisticated ISAP methodology known as the Analytical Ranking Methodology (ARM). This has allowed us to achieve an integrated evaluation and prioritization of proposed and ongoing plant-specific modifications and engineering evaluations at Millstone Unit No. I and the Haddam Neck Plant. The prioritizations have subsequently been utilized in developing Integrated Implementation Schedules (115) for each plant, which are routinelv submitted to the NRC and most recently on May 31, 1991 and March 28, 1991, ;pectively. NNEC0 has, for some time, been taking steps toward applying the ISAP to Millstone Unit No. 3, by identifying topics to be evalu-ated and defining the scope for those topics. We are very encouraged by the results of the ISAP and are now extending this methodology to Millstone Unit No. 3.

Cons ,W 4n and expansion of the ISAP, as stated in our response (I) to GL 8842 (3AP II), further demonstrates the program to be a mutually efficient regulatory and utility process for enhancing safe reactor operations on a properly prioritizcd and resource effective basis. ine enhanced interactive approach between NNECO and the NRC, as discussed with the NRC Staff during the June 28, 1990, November 8, 1990, and May 23, 1991 counterparts meetings, continues to evolve toward enhanced understanding and issue resolution. The ISAP has helped to foster this environment of cooperation where we can jointly review and evaluate issues.

In GL 88-02, the NRC Staff stated that the ISAP could be incorporated into a licensee's On July 27,plant-sgific 1989 response to the Sege Accident Policy Statement.

and October 31, 1989, NNECO and CYAPC0 submitted comprehensive responses to IPE Severe Accident Vulnerabilities (GL 88-20) .

(1) E. J. Mroczka letter to U.S. Nuclear Regulatory Commission, "Haddam Neck Plant, Millstone Nuclear Pnwer Station, Unit Nos. 1, 2, and 3, a

" Integrated Safety Assessment Program II, Response to Generic Letter 88-02," dated February 19, 1988.

(2) E. J. Mroczka letter to U.S. Nuclear Regulatory Commission, "Haddam Neck Plant, Millstone Nuclear Power Station, Unit Nos.1, 2, and 3, Response to Generic letter 88-20, Individual Pl ant Examinations for Severe Accident," dated July 27, 1989.

(3) E. J. Mroczka letter to U.S. Nuclear Regulatory Commission "Haddam Neck Plant, Millstone Nuclear Power Station, Unit Nos.1, 2, and 3, Response to Generic letter 88-20, Supplement 1, Individual Plant Examination for Severe Accident Vulnerabilities," dated October 31, 1989.

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U.S. Nuclear Regulatory Commission B13436/Page 3 May 31, 1991 i later, NNECO submitted the Millstone Unit No, 3 IPE summary report,(4) in which the ISAP/IPE relationship was again discussed. As discussed in the July 27, 1989 letter, and again in the previously submitted IPE semmary report, Millstone Unit No. 3 currently has a completed, well exercised and updated Probabilistir. Risk Assessment. This capability provides the basis for the public safety attribute evaluation, within the ARM, of unit-specific ISAP topics. This ISAP/IPE linkage further demonstrates the " integrated safety assessment" benefit when evaluating and scheduling the results of the plant-specific IPE.

In conclusion, this expension of the ISAP to Millstone Unit No. 3 is the next logical step in our continued endorsement and application of the ISAP concept at Northeast Utilities. Since the ISAF process is now being formally applied to Millstone Unit No. 3, only a portion of the list of potential modifications has been evaluated through the ARM. The llS, depicted in this first submit-tal, represents implementation dates for only those projects for which ARM evaluations have been completed. As more topics undergo cyclic ARM evalua-tions, their respective implementation status will be included, thus increas-ing the comprehensiveness of the 11S. Subsequent ISAP update reports will be submitted approximately every 6 months with upda'ed information, including the 115.

As always, if you have any questions on the iterial contained in the report, please feel free to contact my staff.

Very truly yours, NORTHEAST NUCLEAR ENERGY COMPANY FOR: E. J. Mroczka I

Senior Vice President i

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W. D. Romberg 7 Vice President cc: See Page 4 (4) E. J. Mroczka letter to U.S. Nuclear Regulatory Commission, " Millstone Nuclear Power Station, Unit No. 3, Response to Generic Letter 88-20, Individual Plant Examination for Severe Accident Vulnerabilities Summary Report Submittal," dated August 31, 1990.

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i U.S. Nuclear Regulatory Commission B13436/Page 4 May 31, 1991 cc: James M. Taylor Executive Director Office of the Executive Director for Operations J. H. Sniezek Deputy Executive Director Nuclear Reactor Regulation Regional Operations Thomas E. Murley Director Office of Nuclear Reactor Regulation F. J. Miraglia -Deputy Director Officu of Nuclear Reactor Regulation ,

W. T. Russell-Associate Director for Inspection & Technical Assessment J. G. Partlow- Associate Director for Projects T. T. Martin--Administrator, Region 1 S. A. Varga--Director, Division of Reactor Projects Regions I/ll J. A. Calvo- Assistant Director for Region 1 J. f. Stolz -Director, Project Directorate 1-4 D. H. Jaffe- Project Manager, Millstone Unit Nos. I and 3 W. J. Raymond, Senior Resident inspector, Millstone Unit Nos.1, 2, and 3 K. S. Kolaczyk Resident inspector, Hillstone Unit No. 3 l

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Table of Contents i Attachment 1 . . . . . . . . . . . Executive Summary Attachment 2 . . . . . . . . . . . Program Overview Attachment 3 . . . . . . . . . . . Prioritization Process Attachment 4 . . . . . . . . . . . Current Analytical Ranking Methodology Attachment 5 . . . . . . . . . . . List of ISAP Topics i Attachment 6 . . . . . . . . . . . Detailed Topic Evaluations Attachment 7 . . . . . . . . . . . Evaluation Summary & Initial Ranking I Attachment 8 . . . . . . . . . . . Integrated Implementation Schedule

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