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NRC Section XI Report - December 2002

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Presented By: Mr. Wally Norris, United States Nuclear Regulatory Commission


NRC Report
Section XI
December 2002

1. Amendment to 10 CFR 50.55a - 97A through 00A

The final amendment to 10 CFR 50.55a incorporating the 1997 Addenda through 2000 Addenda by reference was published on September 26, 2002 (67 FR 60520) and is available at the Office of Federal Register website: http://www.access.gpo.gov/su_docs/fedreg/a010803c.html

Efforts relative to a proposed amendment to 10 CFR 50.55a to incorporate the 2001 Edition/Addenda and the 2002 Addenda have been initiated. The schedule for publication to receive public comments is not yet available.

2. ASME Code Cases - Rulemaking/Regulatory Guides

Four draft regulatory guides were published for public review on December 28, 2001: DG-1090, (Proposed Revision 32 to Regulatory Guide 1.84), "Design, Fabrication, and Materials Code Case Acceptability, ASME Section III; DG-1089, "Operation and Maintenance Code Case Acceptability," ASME OM Code; DG-1091, (Proposed Revision 13 to Regulatory Guide 1.147), "Inservice Inspection Code Case Acceptability, ASME Section XI, Division 1; and DG-1112, "ASME Code Cases Not Approved for Use." The guides address Supplement 4 to the 1992 Edition through Supplement 11 to the 1998 Edition, and OMN-1 through OMN-13. Fifteen comment letters were received on the draft guides, and eight letters were received on the proposed rule. The staff has completed its proposed responses and revised the rule and guides accordingly. The final package is being reviewed by NRC management. The Committee to Review Generic Requirements (CRGR) and Advisory Committee on Reactor Safeguards (ACRS) reviews are being scheduled. It is anticipated that the final rule and guides will be published in early February 2003.

The NRC staff has completed its review of the Code Cases in Supplement 12 to the 1998 Edition through Supplements 1, 2, and 3 to the 2001 Edition. Proposed Revision 33 to Regulatory Guide 1.84, Proposed Revision 14 to Regulatory Guide 1.147, and Proposed Revision 1 to RG XXX, "ASME Code Cases Not Approved for Use," are in office review. These draft guides are scheduled to be published in March 2003.

3. ASME PRA Standard

Draft Regulatory Guide DG-1122, "An Approach for Determining the Technical Adequacy of PRA Results for Risk-Informed Activities," which will provide the NRC position on consensus PRA standards and industry PRA documents, is scheduled to be published for public review and comment (90 days) in December 2002.

4. Risk-Informed Activities

The NRC website contains information at http://www.nrc.gov/what-we-do/regulatory/rulemaking/risk-informed/reactor-safety.html relative to risk-informed activities in the Reactor Safety Arena.

Recent activities in the application of RI-ISI methodology include the extension of the RI-ISI methodology as an alternative to augmented inspection programs for break exclusion region (BER) requirements typically identified in Standard Review Plan Sections 3.6.1 and 3.6.2 piping. Both EPRI and WOG have developed methodologies to expand their current RI-ISI methodologies for this application. The staff has approved the use of the EPRI methodology to change the BER programs (ML021790158). If the BER program is described in the final safety analysis report, licensees may implement changes to the BER program according to the provisions of 10 CFR 50.59. Review of the WOG methodology is continuing. The staff is planning to update the RI-ISI Regulatory Guide 1.178 and SRP Section 3.9.8 by the summer of 2003.

The staff met with NEI and other industry representatives in November 2002 to discuss "living program" guidance for risk-informed in service inspection (RI-ISI) programs. RI-ISI programs must be updated to reflect changes in the plant, and general industry experience that might impact the program. The schedule and extent of such changes is under development. NEI stated that it intends to complete guidance on this process and to provide it to the staff for review and comment by the Spring of 2003. There are currently no plans for the staff to approve the guidance.

5. Generic Activities on PWR Alloy 600/182/82 PWSCC

The Davis-Besse Lessons Learned Task Force report was issued on September 30, 2002. The full 96 page report (plus attachments) is available on the NRC’s web site at: http://www.nrc.gov/reactors/operating/ops-experience/vessel-head-degradation/news.html. The third periodic update (November 2002 Issue) on the NRC response to the reactor vessel head damage at the Davis-Besse Nuclear Power Station is available at the above website address. One item of note is that the results of bottom vessel head nozzle tests are inconclusive. FirstEnergy identified rust stains on the bottom of the reactor vessel in June 2002 when plant workers removed the insulation from the reactor vessel in order to examine its condition. The licensee believes the stains probably resulted from previous cleaning of the reactor vessel head. Leakage from the penetrations for incore monitoring tubes has not positively been ruled out however. There has been no history of such leakage in other U.S. pressurized water reactors. Framatome has performed an analysis of the chemical composition of the corrosion products from the top of the reactor and stains on the bottom, but the analyses did not provide a conclusive link to the upper vessel head cleaning; nor did they show evidence of leakage from the incore tube penetrations. Davis-Besse is reviewing its options for definitive testing of the bottom nozzles for leaks. The NRC will review the utility's testing and inspection plans and monitor the tests. The issue will be resolved prior to the NRC considering whether the plant can restart. On November 8, 2002, the NRC staff posted on its web site model requests for additional information (RAIs) related to boric acid corrosion control programs (NRC Bulletin 2002-01). Plant-specific RAIs have subsequently been issued to each licensee. The bulletin requested licensees to submit the basis for concluding that their boric acid inspection programs provide reasonable assurance of compliance with the applicable regulatory requirements discussed in Generic Letter 88-05 and the bulletin. Most of the licensees' 60-day responses lacked specificity, and the NRC staff could not complete its review of the boric acid corrosion control (BACC) programs in light of the lessons learned from the Davis-Besse event. The staff concluded that the information requested in Bulletin 2002-01 may not have been sufficiently focused. The NRC staff's review of the licensees' 60-day responses provided the basis for development of the questions in the request for additional information (RAI). Licensees are expected to provide responses in sufficient detail to facilitate a comprehensive staff review of their BACC programs.

6. Future Reactor Licensing Activities - Advanced Reactor Infrastructure Assessment

In response to Staff Requirements Memorandum (SRM) for COMJSM-00-0003, the staff prepared and issued information paper, "Future Licensing and Inspection Readiness Assessment [FLIRA]," SECY-01-0188, dated October 12, 2001. The FLIRA committed the staff to perform an advanced reactor Infrastructure Assessment (IA), to set directions for research programs, and to identify necessary tools and expertise necessary to support the regulation of new reactor designs. In response to that commitment, the staff identified technology gaps and Agency needs in the form of methods, tools, data, and expertise. These needs are primarily associated with non-LWRs. Recently Exelon’s withdrawal of their pre-application review for the PBMR, however, has impacted and shifted research priorities. Accordingly, High Temperature Gas Cooled Reactors (HTGRs) research has been scaled back but not eliminated. HTGR research will remain focused at generic level, and on Gas Turbine-Modular Helium Reactor (GT-MHR) design. The GT-MHR will undergo pre-application review during FY03-FY04. In addition, many of the key technical issues identified in the IA (e.g., high temperature materials, graphite, and TRISO fuel particle performance) are generic to all HTGRs and as such, will receive a higher priority over those considered to be associated with a particular plant design. Advanced reactor research has also been identified for reactor designs that have been submitted since the IA was performed, e.g., ESBWR, SWR-1000, and ACR-700. These new activities will be added to the IA. The IA has been transmitted to the NRC Executive Director for Operations.

7. Risk-Informing 10 CFR Part 50 (Option 2)

The NRC staff has prepared a proposed rule, 10 CFR 50.69, "Risk-Informed Treatment of Structures, Systems, and Components," under Option 2 of the NRC’s initiative to incorporate risk insights into its regulations. The Commission has sought for a number of years to find various ways to use the risk insights gained to shape the NRC’s regulatory system in new ways. Option 2 was to focus on the requirements dealing with safety-related structure systems and components (SSC's). Consistent with Commission direction, the staff made its preliminary rule language publicly available on the NRC website on November 29, 2001. The staff reviewed the comments received on the draft rule and posted a revision to the draft rule dated April 3, 2002. Comments on the revised draft rule were received from NEI in a letter dated May 15, 2002, and from ASME in letters dated June 3 and 17, 2002. A public meeting was held on June 18, 2002, to discuss the NEI and ASME comments. The NRC staff considered the comments and posted a further revised draft rule dated July 31, 2002. NEI is preparing guideline document NEI 00-04, "Option 2 Implementation Guidance." On Thursday November 21, 2002, a Commission briefing was held on risk informing special treatment requirements (the proposed rule and Differing Professional Views [DPV] on the proposed 10 CFR 50.69 rule package are available at http://www.nrc.gov/reading-rm/doc-collections/commission/slides/2002/20021121/. The filers of the DPV believe that the treatment of RISC-3 components is not sufficient to maintain safety and protect the public health and safety. The staff has focused its review of NEI 00-04 on categorization, and did not plan to develop or endorse regulatory guidance for treatment of RISC-3 components. NEI submitted a draft of NEI 00-04 on June 28, 2002. On August 14, 2002, the NRC staff provided comments to NEI on the guidance document (ADAMS Accession No. ML022270004). The NRC staff plans to complete a regulatory guide that would endorse NEI 00-04 with clarifications and exceptions, as necessary. At the present time, there are a number of issues that need further discussion and development before NRC can complete such a document.

Pilot plant activities at Wolf Creek, Surry, Quad Cities, and Palo Verde were conducted to evaluate the proposed NEI Option 2 implementing guidance (NEI 00-04). The staff plans to use the lessons learned from these efforts to improve the NEI guidance and the Option 2 regulatory framework. There are issues that remain to be resolved in the implementation guidance.


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