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IR 05000298-10-008; 05/05/2010 - 07/29/2010; Cooper Nuclear Station; Followup of License Renewal Unresolved Item Related to Suppression Chamber Pitting Inspection Report
	ML102230027
Person / Time
Site:	Cooper
Issue date:	08/10/2010
From:	O'Keefe N; NRC/RGN-IV/DRS/EB-2
To:	O'Grady B; Nebraska Public Power District (NPPD)
References
	IR-10-008
	Download: ML102230027 (12)
	v • d • e

UNITED STATES NUC LE AR RE G ULATO RY C O M M I S S I O N ust 10, 2010

SUBJECT:

COOPER NUCLEAR STATION - FOLLOWUP OF LICENSE RENEWAL UNRESOLVED ITEM RELATED TO SUPPRESSION CHAMBER PITTING -

INSPECTION REPORT 05000298/2010008

Dear Mr. OGrady:

On July 29, 2010, the U.S. Nuclear Regulatory Commission (NRC) completed their review of Unresolved Item 05000298/2009010-01, which documented concerns with your aging management plan for the containment suppression chamber coating. We have discussed the results of our review with Mr. A. Zaremba, Director, Nuclear Safety Assurance, and other members of your staff during an exit meeting conducted on July 29, 2010.

This license renewal followup inspection examined activities related to your application for a renewed license for Cooper Nuclear Station and to the impact during the current operating period. The inspection evaluated whether you maintained the design basis of your torus coating as required by our regulatory requirements. As part of the inspection, the NRC examined procedures and representative records and interviewed personnel.

As a result of our review, we concluded that no violations of regulatory requirements had resulted from this coating degradation. We have concluded that the commitment to recoat the wetted portion of your suppression chamber combined with increased frequency of the ASME,Section XI, Subsection IWE inspections provided reasonable assurance that the effects of aging resulting from the degraded coating would be effectively managed until you completed recoating the suppression chamber.

Nebraska Public Power District -2-In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter, and its enclosure, will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records component of NRCs document system (ADAMS).

ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).

Sincerely,

/RA/

Neil O'Keefe, Chief Engineering Branch 2 Division of Reactor Safety Docket: 50-298 License: DPR-46 NRC Inspection Report 05000298/2010008 w/Attachment: Supplemental Information Gene Mace Michael J. Linder, Director Nuclear Asset Manager Nebraska Department of Nebraska Public Power District Environmental Quality P.O. Box 98 P.O. Box 98922 Brownville, NE 68321 Lincoln, NE 68509-8922 John C. McClure, Vice President Randy Rohrs, Chairman and General Counsel Nemaha County Board of Commissioners Nebraska Public Power District Nemaha County Courthouse P.O. Box 499 1824 N Street, Suite 201 Columbus, NE 68601 Auburn, NE 68305 David VanDerKamp Julia Schmitt, Manager Licensing Manager Nebraska Department of Health Nebraska Public Power District and Human Services P.O. Box 98 Division of Public Health Brownville, NE 68321 Nebraska State Office Building, 3rd Fl Lincoln, NE 68509-5026

Nebraska Public Power District -3-Deputy Director for Policy John F. McCann, Director, Licensing Missouri Department of Natural Resources Entergy Nuclear Northeast P.O. Box 176 Entergy Nuclear Operations, Inc Jefferson City, MO 65102-0176 440 Hamilton Avenue White Plains, NY 10601-1813 Director, Missouri State Emergency Management Agency Keith G. Henke, Planner P.O. Box 116 Division of Community and Public Health Jefferson City, MO 65102-0116 Office of Emergency Coordination P.O. Box 570 Chief, Radiation and Asbestos Jefferson City, MO 65102 Control Section Kansas Department of Health Art Zaremba and Environment Director of Nuclear Safety Assurance Bureau of Air and Radiation Nebraska Public Power District 1000 SW Jackson, Suite 310 P.O. Box 98 Topeka, KS 66612-1366 Brownville, NE 68321 Melanie Rasmussen, State Liaison Officer/ Ronald D. Asche, President Radiation Control Program Director and Chief Executive Officer Bureau of Radiological Health Nebraska Public Power District Iowa Department of Public Health 1414 15th Street Lucas State Office Building, 5th Floor Columbus, NE 68601 321 East 12th Street Des Moines, IA 50319 Chief, Technological Hazards Branch FEMA, Region VII 9221 Ward Parkway Suite 300 Kansas City, MO 64114-3372

Nebraska Public Power District -4-Electronic distribution by RIV:

Regional Administrator (Elmo.Collins@nrc.gov)

Deputy Regional Administrator (Chuck.Casto@nrc.gov)

Acting DRP Director (Anton.Vegel@nrc.gov)

Acting DRP Deputy Director (Troy.Pruett @nrc.gov)

DRS Director (Roy.Caniano@nrc.gov)

Acting DRS Deputy Director (Jeff.Clark@nrc.gov)

Senior Resident Inspector (Nick.Taylor@nrc.gov)

Resident Inspector (Michael.Chambers@nrc.gov)

Branch Chief, DRP/C (Vincent.Gaddy@nrc.gov)

Senior Project Engineer, DRP/C (Bob.Hagar@nrc.gov)

CNS Administrative Assistant (Amy.Elam@nrc.gov)

Public Affairs Officer (Victor.Dricks@nrc.gov)

Public Affairs Officer (Lara.Uselding@nrc.gov)

Project Manager (Fred.Lyon@nrc.gov)

Branch Chief, DRS/TSB (Michael.Hay@nrc.gov)

RITS Coordinator (Marisa.Herrera@nrc.gov)

Regional Counsel (Karla.Fuller@nrc.gov)

Congressional Affairs Officer (Jenny.Weil@nrc.gov)

OEMail Resource ROPreports Only inspection reports to the following:

DRS/TSB STA (Dale.Powers@nrc.gov)

OEDO RIV Coordinator (Margie.Kotzalas@nrc.gov)

R:\REACTORS\_CNS\2010\CNS2010008 LRI-GAP ADAMS ML ADAMS: No ; Yes ; SUNSI Review Complete Reviewer Initials: GAP

Publicly Available ; Non-Sensitive Non-publicly Available Sensitive RIV: DRS/EB2 C:DRP/C C:EB2 GAPick VGGaddy NOKeefe

/RA/ /RA/ /RA/

07/9/10 07/9/10 08/10/10 OFFICIAL RECORD COPY T=Telephone E=E-mail F=Fax

U.S. NUCLEAR REGULATORY COMMISSION

REGION IV

Docket: 50-298 License: DRP-46 Report: 05000298/2010008 Licensee: Nebraska Public Power District Facility: Cooper Nuclear Station Location: 72676 648A Ave Brownville, NE 68321 Dates: May 5 through July 29, 2010 Inspectors: G. Pick, Senior Reactor Inspector Approved By: Neil O'Keefe, Chief Engineering Branch 2 Division of Reactor Safety-1- Enclosure

SUMMARY OF FINDINGS

IR 05000298/2010008; 05/05/2010 - 07/29/2010; Cooper Nuclear Station, Followup of License

Renewal Unresolved Item The report covered a 3-month period of in-office review and evaluation by a senior regional inspector.

NRC-Identified and Self-Revealing Findings

B.

Cornerstone: Mitigating Systems

No findings were identified.

Licensee-Identified Violations

No findings were identified.

REPORT DETAILS

OTHER ACTIVITIES (OA)

4OA5 Other - License Renewal

(Closed) Unresolved Item 05000298/2009010-01: Adequacy of Aging Management for the Torus Background As described in Inspection Report 05000298/2009010, the license renewal inspection team had identified concerns related to the adequacy of the coating on the wetted portion of the containment suppression chamber (torus) because of the degraded conditions of the coating. Specifically, the applicant identified a large amount of general corrosion and localized pitting during each of the last three ASME,Section XI, Subsection IWE inspections (approximately 600 localized areas during each inspection)on the wetted surface of the torus. The license renewal inspection team concluded that the applicant continued to meet the ASME,Section XI, Subsection IWE requirements for assuring the structural integrity of the torus. However, the license renewal inspection team was concerned that the applicant may not have planned appropriate actions to manage the effects of aging for the submerged portions of the torus during the period of extended operation since the corrosion present appeared to indicate that the coating no longer provided the required protection from erosion and/or corrosion.

Evaluation The Updated Final Safety Analysis Report discussed the suppression chamber coating and the need to prevent corrosion of this safety-related structure required for safe shutdown. Chapter 5, Section 2.3.3.2, identified that the lower half (i.e., wetted area) of the suppression chamber had a general corrosion allowance of 3/32 inches. Chapter 5, Section 2.5.1, specified the interior surfaces of the drywell and suppression chamber, including waterline regions, shall be visually inspected each refueling outage cycle for evidence of corrosion or leakage.

In Engineering Evaluation 01-047, the licensee specified that:

(1) the protective coatings applied to surfaces inside the primary containment were nuclear safety related;

(2) the application of coatings was a special process as defined in 10 CFR Part 50, Criterion IX; and

(3) the original coatings applied to surfaces inside containment provided corrosion protection and prevented degradation of the substrate as long as the coating remained as a continuous film intact on the surface.

Subsequent to opening this unresolved item, the applicant committed in Letter NLS2010050, Response to Open Items from the Safety Evaluation Report and Request for Additional Information Related to the License Renewal of Cooper Nuclear Station, dated May 4, 2010, to recoat the suppression chamber, which would occur no later than 3 years after entering the period of extended operation. As a compensatory measure, the applicant committed to increase the frequency of inspections of the wetted surfaces of the suppression chamber and analyze the impact and any growth of the pitting that may be occurring. The applicant described in the letter that the amount of material remaining at their observed pitting corrosion rate of 2 mils per year would allow operation for an additional next 20 years without exceeding minimum wall thickness.

Because of the remaining wall thickness and the apparent corrosion rates, the inspector concluded that the suppression chamber wall should remain unaffected until the applicant recoated the suppression chamber wall. Consequently, the commitment to recoat the wetted portion of the suppression chamber combined with the increased frequency of inspection and evaluation provided additional assurance that the applicant would remain aware of the suppression chamber condition and maintain the ability of the suppression chamber to perform its safety-related function.

The applicant documented this issue and their commitments in Condition Report 2010-04515.

Conclusion The inspector determined that the applicant had taken appropriate actions to address the effects of aging that resulted in a degraded suppression chamber coating.

Specifically, the applicant committed to:

(1) recoat the suppression chamber within 3 years of entering the period of extended operation;

(2) conduct increased ASME,Section XI, Subsection IWE inspections of the wetted portion of the suppression chamber each outage rather than every other outage; and

(3) conduct a pitting analysis following each inspection The inspector determined that these actions provided reasonable assurance that the licensee implemented actions to manage the aging of the suppression chamber that resulted in corrosion because of degraded coatings.

This unresolved item is considered closed.

4OA6 Meetings

Exit Meeting Summary

On July 29, 2010, the inspector presented the results of the in-office inspection of the suppression chamber reviews to Mr. A. Zaremba, Director, Nuclear Safety Assurance, and other members of the applicants staff. The applicant acknowledged the issues presented. No proprietary information was identified.

SUPPLEMENTAL INFORMATION

KEY POINTS OF CONTACT

Licensee Personnel

D. Bremer, Project Manager, License Renewal

D. Buman, Director, Engineering

D. VanDerKamp, Manager, Licensing

W. Victor, Licensing Engineer

A. Zaremba, Director, Nuclear Safety Assurance

NRC Personnel

R. Auluck, Chief, Aging Management of Structures,

Electrical, and Systems Branch, Division of License Renewal

A. Sheikh, Senior Engineer, Aging Management of Structures,