2CAN099706, Forwards Results of Pilot Plant Application Study Performed at Ano,Unit 2 for Review.Prompt Staff Review Is Requested. Formal Request for NRC Approval Will Be Made Following Submittal of Svc Water Sys Risk Evaluation in Dec 1997

Forwards Results of Pilot Plant Application Study Performed at Ano,Unit 2 for Review.Prompt Staff Review Is Requested. Formal Request for NRC Approval Will Be Made Following Submittal of Svc Water Sys Risk Evaluation in Dec 1997

ML20217E899
Person / Time
Site:	Arkansas Nuclear
Issue date:	09/30/1997
From:	Mims D ENTERGY OPERATIONS, INC.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20217E904	List: 2CAN099706, Forwards Results of Pilot Plant Application Study Performed at Ano,Unit 2 for Review.Prompt Staff Review Is Requested. Formal Request for NRC Approval Will Be Made Following Submittal of Svc Water Sys Risk Evaluation in Dec 1997 ML20217E921 ML20217E929 ML20217E938 ML20217E950 ML20217E967 ML20217E987 ML20217F007 ML20217F029 ML20217F092
References
2CAN099706, 2CAN99706, NUDOCS 9710070298
Download: ML20217E899 (3)

Text

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Ent:rgy operations,Inc.

/hf'O O 1448 S R 333 RexMo. AR 72601 Tal 501858-5000 September 30,1997 2CAN099706 U. S. Nuclear Regulatory Comm!ssion Document Control Desk Mail Station OPI-17 Washington, DC 20555

Subject:

Arkansas Nuclear One - Unit 2 Docket No. 50-368 License No. NPF-6 Risk-Informed Inservice Inspection Pilot Plant Submittal for ANO-2 i Gentlemen:

As indicated in a letter from the Nuclear Energy Institute (NEI) to the NRC dated August 29, 1997, entitled " Risk Informed In-Service Inspection Industry Submittals," Entergy Operations is submitting for NRC review the results of the pilot plant application study performed at Arkansas Nuclear One, Unit 2 (ANO-2). The principal objective of a risk-informed inservice inspection (ISI) spproach is to focus resources on higner risk elements. Entergy believes that achieving this objective will result in increased plant safety and a significant reduction in worker radiation exposure, while also reducing plant operating and maintenance costs.

This project was sponsored by the Combustion Engineering Owners Group (CEOG) in tailored collaboration with the Electric Power Research Institute (EPRI). The ANO-2 study was performed consistent with ASME Code Case N-578, " Risk-Based Rules for Class 1,2 and 3 Piping," utilizing the EPRI risk-informed inservice inspection methodology. The following eight system risk evaluations are enclosed for NRC review,

l. A-PENG-CALC-010, Rev. 00, Implementation of the EPRI Risk-Informed Inservice Inspection Evaluation Procedure for the High Pressure Safety Injection System at ANO-2

2. A-PENG-CALC-012, Rev. 00, Implementation of the EPRI Risk-Informed Inservice

/

Inspection Evalustion Procedure for the Reactor Coolant System at ANO-2

3. A-PENG-CALC-014, Rev. 00, Implementation of the EPRI Risk-Informed Inserviceh Inspection Evaluation Procedure for the Chemical and Volume Control System at ANO-2

4. A-PENG-CALC-015, Rev 00, Implementation of the EPRI Risk-Informed Inservice Inspection Evaluation Procedure for the Containment Spray System at ANO-2 9710070298 970930 PDR ADOCK 05000368 a

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- 2CAN099706 Page 2

5. -A-PENG-CALC-016, Rev. 00, . Implementation of the EPRI Risk Informed Inservice Inspection Evaluation Procedure for the Low Pressure Safety Injection and Shutdown -

Cooling Systems at ANO.2

6. A-PENG CALC-017, Rev. 00, Implementation of the EPRI Risk Informed Inservice Inspection Evaluation Procedure for the Emergency Feedwater System at ANO-2

7. A PENG-CALC-018, Rev. 00, Implementation of the EPRI Risk Informed Inservice Inspection Evaluation Procedure for the Main Feedwater System at ANO-2

8. A PENG-CALC 019, Rev. 00, Implementation of the EPRI Risk-Informed Inservice l Inspection Evaluation Procedure for the Main Steam System at ANO-2 The August 29, 1997, NEI letter referenced previously failed to mention that the risk evaluation of the service water system, which is-in process, will not be submhted until

- December 1997, s

- ABB _ Combustion Engineering (ABB-CE) functioned as the principal investigator in the application of the EPRI Risk Informed Inservice Inspection Evaluation Procedure to the l - ANO-2 pilot study. ' ABB-CE was assisted in the consequence evaluation and failure potential assessment for cert.in systems by Yankee Atomic and Structural Integrity Associates, respectively. Calculation NSD-018, " Consequence Evaluation of ANO 2 EFW, Containment Spray, and Main Steam & Feedwater System Piping," which was prepared by Yankee Atomic as input to the applicable ABB-CE system calculations listed above, is also enclosed for NRC reference.

To support the project, Entergy assembled a dedicated team of plant staff with diverse experience in probabilistic risk assessment, operations, inservice inspection and structural analysis. The plant team's project support duties included-the collection of the required design inputs, respondmg to inquiries from the principal investigators, resolution of issues arising during the evaluations, participation in plant walkdowns to assess spatial interactions, review of_ the plant service history relative to piping pressure boundary degradation-occurrences and a thorough review of each aspect of the system calculations with primary focus on the technical accuracy _and adequacy of the system consequence evaluations and failure potential assessments. This team, which interfaced with other plant staff personnel

- (e.g., operations, system engineering, chemistry, etc.) on an as needed basis, ensured that plant specific knowledge and insights were factored into the risk evaluations. This day-to-day involvement in the project enabled the plant staff to actively participate in the performance of the system risk evaluations and promoted ownership in the effort.

Even though the system risk evaluations have been rigorously reviewed by the plant project team, ANO intends to. subject the system risk evaluations to an additional plant review in parallel with the NRC's review. This review, which is targeted for this fall, will consist of a completely independent review by plant staff from various departments. Entergy chose to delay this integrated plant review pending the incorporation of all review comments from the plant project team and the ABB-CE technical reviewers to enable this final independent review tb De performed on completed system calculation packages. Entergy believes any potential comment: that will result from this review will be minimal because of the intensive

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s. _.

U. S. NRC

o- September 30,1997 2CAN099706- Page 3 review pe formed by the plant project team, and as such, believes that submittal of the system risk evaluations at thia time is appropriate.

Entergy requests prompt staff review of this submittal. A formal request for NRC approval will be made following the submittal of the service water system risk evaluation in December--

-1997.

Should you have any questions or comments, please contact me.

Very truly yours, l

b. 12 %

Dwight C. Mime Director, Nuclear Safety DCM/dwb Enclosures

cc

Mr. Ellis W. Merschoff Regional Administrator U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 760118064 NRC Senior Resident Inspector Arkansas Nuclear One -

P.O. Box 310

- London, AR 72847 -

Mr. George Kalman 2 NRR Project Manager Region IV/ANO-1 & 2 U. S. Nuclear Regulatory Commission NRR Mail Stop 13-H-3 One White Flint North

- 11555 Rockville Pike Rockville, MD 20852 M _