IR 05000298/2010008

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)

Text

August 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.

UNITED STATES NUCLEAR REGULATORY COMMISSION R E GI ON I V 612 EAST LAMAR BLVD, SUITE 400 ARLINGTON, TEXAS 76011-4125

Nebraska Public Power District

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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 Nuclear Asset Manager Nebraska Public Power District P.O. Box 98 Brownville, NE 68321

John C. McClure, Vice President and General Counsel Nebraska Public Power District P.O. Box 499 Columbus, NE 68601

David VanDerKamp Licensing Manager Nebraska Public Power District P.O. Box 98 Brownville, NE 68321

Michael J. Linder, Director Nebraska Department of Environmental Quality P.O. Box 98922 Lincoln, NE 68509-8922

Randy Rohrs, Chairman Nemaha County Board of Commissioners Nemaha County Courthouse 1824 N Street, Suite 201 Auburn, NE 68305

Julia Schmitt, Manager Nebraska Department of Health and Human Services Division of Public Health Nebraska State Office Building, 3rd Fl Lincoln, NE 68509-5026

Nebraska Public Power District

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Deputy Director for Policy Missouri Department of Natural Resources P.O. Box 176 Jefferson City, MO 65102-0176

Director, Missouri State Emergency Management Agency P.O. Box 116 Jefferson City, MO 65102-0116

Chief, Radiation and Asbestos Control Section Kansas Department of Health and Environment Bureau of Air and Radiation 1000 SW Jackson, Suite 310 Topeka, KS 66612-1366

Melanie Rasmussen, State Liaison Officer/

Radiation Control Program Director Bureau of Radiological Health Iowa Department of Public Health Lucas State Office Building, 5th Floor 321 East 12th Street Des Moines, IA 50319

John F. McCann, Director, Licensing Entergy Nuclear Northeast Entergy Nuclear Operations, Inc 440 Hamilton Avenue White Plains, NY 10601-1813

Keith G. Henke, Planner Division of Community and Public Health Office of Emergency Coordination P.O. Box 570 Jefferson City, MO 65102

Art Zaremba Director of Nuclear Safety Assurance Nebraska Public Power District P.O. Box 98 Brownville, NE 68321

Ronald D. Asche, President and Chief Executive Officer Nebraska Public Power District 1414 15th Street Columbus, NE 68601

Chief, Technological Hazards Branch FEMA, Region VII 9221 Ward Parkway Suite 300 Kansas City, MO 64114-3372

Nebraska Public Power District

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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

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Enclosure

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

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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

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,

Electrical, and Systems Branch, Division of License Renewal

LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED

Closed

05000298/2010-001 URI Adequacy of Aging Management for the Torus (Section 4OA5)