ML082540516

Generic Letter 2008-01. Managing Gas Accumulation in Emergency Core Cooling Decay Heat Removal and Containment Spray

ML082540516
Person / Time
Site:	Oconee, Mcguire, Catawba, McGuire
Issue date:	09/25/2008
From:	Melanie Wong Plant Licensing Branch II
To:	Harrall T Duke Energy Carolinas
Olshan L N, NRR/DORL, 415-1419
References
TAC MD7809, TAC MD7810, TAC MD7843, TAC MD7844, TAC MD7852, TAC MD7853, TAC MD7854
Download: ML082540516 (14)

Text

September 25, 2008 Mr. Thomas P. Harral, Jr.

Vice President, Plant Support Nuclear Generation Duke Energy Carolinas, LLC 526 South Church Street Charlotte, NC 28202

SUBJECT:

CATAWBA NUCLEAR STATION, UNITS 1 AND 2; MCGUIRE NUCLEAR STATION, UNITS 1 AND 2; AND OCONEE NUCLEAR STATION, UNITS 1, 2, AND 3, RE: GENERIC LETTER 2008-01, MANAGING GAS ACCUMULATION IN EMERGENCY CORE COOLING, DECAY HEAT REMOVAL, AND CONTAINMENT SPRAY SYSTEMS, PROPOSED ALTERNATIVE COURSE OF ACTION (TAC NOS. MD7809, MD7810, MD7843, MD7844, MD7852, MD7853, AND MD7854)

Dear Mr. Harral:

On January 11, 2008, the Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems (Agencywide Documents Access and Management System (ADAMS) Accession No. ML072910759). The GL requested licensees to submit information to demonstrate that the emergency core cooling, decay heat removal, and containment spray systems (hereinafter referred to as the subject systems) are in compliance with the current licensing and design bases and applicable regulatory requirements, and that suitable design, operational, and testing control measures are in place for maintaining this compliance.

In accordance with Section 50.54(f) of Title 10 of the Code of Federal Regulations (10 CFR),

GL 2008-01 required that each licensee submit the requested information within 9 months (hereinafter referred to as the 9-month submittal) of the date of the GL. The GL also stated that if a licensee cannot meet the requested 9-month response date, the licensee is required to provide a response within 3 months (hereinafter referred to as the 3-month submittal) of the date of the GL, describing the alternative course of action it proposes to take, including the basis for the acceptability of the proposed alternative course of action.

By letter dated May 8, 2008, Duke Energy Carolinas, LLC (the licensee) submitted a 3-month response to GL 2008-01 for Oconee Nuclear Station, Units 1, 2, and 3, McGuire Nuclear Station, Units 1 and 2, and Catawba Nuclear Station, Units 1 and 2. The NRC staffs assessment of the responses for Oconee Nuclear Station, Units 1, 2, and 3, McGuire Nuclear Station, Units 1 and 2, and Catawba Nuclear Station, Unit 2 is contained in the enclosures to this letter.

The NRC staff reviewed the licensees proposed alternative course of action and the associated basis for acceptance and concluded that for Oconee Nuclear Station, Units 1, 2, and 3, McGuire Nuclear Station, Units 1 and 2, and Catawba Nuclear Station, Unit 2, with the exception of the clarifications and associated requests discussed in the enclosures, they are acceptable. This letter allows the licensee to implement its proposed alternative course of action provided that

T. Harrall Jr. implementation is consistent with the clarifications and associated requests discussed in the enclosure.

If you have any questions regarding this letter, please feel free to contact Mr. Leonard N.

Olshan at 301 415-1419.

Sincerely,

/RA/

Melanie C. Wong, Chief Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-413, 50-414, 50-369, 50-370, 50-269, 50-270, and 50-287

Enclosures:

As stated cc w/encls: See next page

T. Harrall Jr. implementation is consistent with the clarifications and associated requests discussed in the enclosure.

If you have any questions regarding this letter, please feel free to contact Mr. Leonard N.

Olshan at 301 415-1419.

Sincerely,

/RA/

Melanie C. Wong, Chief Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-413, 50-414, 50-369, 50-370, 50-269, 50-270, and 50-287

Enclosures:

As stated cc w/encls: See next page DISTRIBUTION:

PUBLIC RidsOgcRpResources LPL II-1 R/F RidsAcrsAcnw_MailResource RidsNrrDorlLpl 2-1 MWong RidsRgn2_MailCenterResource RidsNrrLAMOBrien DBeaulieu, DPR/PGCB RidsNrrPMLOlshan SSun, DSS/SRXB RidsNrrPMJStang WLyon, DSS/SRXB RidsNrrDorlDPR ADAMS Accession Number:ML082540516 NRR-106 OFFICE LPL2-1 PM LPL2-1 PM LPL2-1 LA PGCB/BC DSS/DD LPL2-1 BC NAME LOlshan JStang MOBrien MMurphy JWermiel MWong DATE 9/22 /08 9/22/08 9/24/08 9/23/08 9/22/08 9/25/08 OFFICIAL RECORD COPY

Catawba Nuclear Station, Units 1 & 2 09/30/2008 G:\ADRO\DORL\LPL2-1\Boilerplates\PLANT MAILING LISTS\Catawba.doc cc:

Site Vice President Catawba Nulcear Station Duke Power Company, LLC Senior Resident Inspector 4800 Concord Road U.S. Nuclear Regulatory Commission York, SC 29745 4830 Concord Road York, South Carolina 29745 Associate General Counsel and Managing Attorney Manager Duke Energy Carolinas, LLC Division of Waste Management 526 South Church Street - EC07H Bureau of Land and Waste Management Charlotte, North Carolina 28202 Dept. of Health and Environmental Control 2600 Bull Street Regulatory Compliance Columbia, South Carolina 29201-1708 Duke Energy Corporation 4800 Concord Road Manager York, South Carolina 29745 Nuclear Regulatory Issues and Industry Affairs North Carolina Municipal Power Duke Energy Corporation Agency Number 1 526 South Church Street 1427 Meadowwood Boulevard Mail Stop EC05P P.O. Box 29513 Charlotte, North Carolina 28202 Raleigh, North Carolina 27626 Saluda River Electric County Manager of York County P.O. Box 929 York County Courthouse Laurens, South Carolina 29360 York, South Carolina 29745 Vice President Piedmont Municipal Power Agency Customer Relations and Sales 121 Village Drive Westinghouse Electric Company Greer, South Carolina 29651 6000 Fairview Road 12th Floor Assistant Attorney General Charlotte, North Carolina 28210 North Carolina Department of Justice P.O. Box 629 Owners Group (NCEMC)

Raleigh, North Carolina 27602 Duke Energy Corporation 4800 Concord Road NCEM REP Program Manager York, South Carolina 29745 4713 Mail Service Center Raleigh, North Carolina 27699-4713 Senior Counsel Duke Energy Carolinas, LLC North Carolina Electric Membership Corp. 526 South Church Street - EC07H P.O. Box 27306 Charlotte, NC 28202 Raleigh, North Carolina 27611

Catawba Nuclear Station, Units 1 & 2 cc:

Division of Radiation Protection NC Dept. of Environment, Health, and Natural Resources 3825 Barrett Drive Raleigh, North Carolina 27609-7721 Group Vice President, Nuclear Generation and Chief Nuclear Officer P.O. Box 1006-EC07H Charlotte, NC 28201-1006 Enclosure 1

ASSESSMENT OF 3-MONTH RESPONSE TO GENERIC LETTER 2008-01 OCONEE NUCLEAR STATION, UNIT NOS. 1, 2, AND 3 DOCKET NOS. 50-269, 50-270, AND 50-287

1. Background

On January 11, 2008, the Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems (Agencywide Documents Access and Management System (ADAMS) Accession No. ML072910759). The GL requested licensees to submit information to demonstrate that the emergency core cooling, decay heat removal, and containment spray systems (hereinafter referred to as the subject systems) are in compliance with the current licensing and design bases and applicable regulatory requirements, and that suitable design, operational, and testing control measures are in place for maintaining this compliance.

Specifically, the GL requested licensees to provide: (1) a description of the results of evaluations that were performed in response to the GL; (2) a description of all corrective actions that the licensee determined were necessary; and (3) a statement regarding which corrective actions were completed, the schedule for completing the remaining corrective actions, and the basis for that schedule.

In accordance with Section 50.54(f) of Title 10 of the Code of Federal Regulations (10 CFR),

GL 2008-01 required that each licensee submit the requested information within 9 months (hereinafter referred to as the 9-month submittal) of the date of the GL. The GL also stated that if a licensee cannot meet the requested 9-month response date, the licensee is required to provide a response within 3 months (hereinafter referred to as the 3-month submittal) of the date of the GL, describing the alternative course of action it proposes to take, including the basis for the acceptability of the proposed alternative course of action.

2. Licensees Proposed Alternative Course of Action By letter dated May 8, 2008, Duke Energy Carolinas, LLC (the licensee) submitted a 3-month response to GL 2008-01 for Oconee Nuclear Station, Units 1, 2, and 3. The licensee stated they cannot meet the requested 9-month schedule for submitting the requested information because field verifications (surveys and walkdowns) of some segments of piping for the GL subject systems, including the high pressure injection and low pressure injection system, and residual heat removal system cannot be completed for the following reasons: (1) the verification requires entry into the containment or areas of high radiation; and (2) removal of insulation from piping may cause undesired safety consequences.

The licensee also stated that the drawing reviews and procedure reviews will be completed during the 9-month timeframe prescribed in the GL (i.e., by October 11, 2008). As an alternative course of action, the licensee plans to complete evaluations requiring field verifications, which are presently scheduled for the Oconee Unit 1, fall 2009 refueling outage, Oconee Unit 2, fall 2008 refueling outage, and Oconee Unit 3, spring 2009 refueling outage.

The licensees letter dated May 8, 2008, listed the following commitments for the Oconee Nuclear Station, Units 1, 2, and 3.:

1. Complete field verification activities on Unit 1. Evaluate the results and identify corrective actions. Send this information to the NRC by follow-on submittal within 90 days after the end of the fall 2009 refueling outage.

2. Complete field verification activities on Unit 2. Evaluate the results and identify corrective actions. Send this information to the NRC by follow-on submittal within 90 days after the end of the fall 2008 refueling outage.

3. Complete field verification activities on Unit 3. Evaluate the results and identify corrective actions. Send this information to the NRC by follow-on submittal within 90 days after the end of the spring 2009 refueling outage.

The licensee stated that the alternative course of action is acceptable based on the following:

1. The scope of deferred evaluation activities is small. The alternative course of action provides for completion of evaluations in three of the four areas of concern in accordance with the schedule required by the GL. In the fourth area, only those evaluation activities involving field verifications are deferred. Those deferrals provide for completion of these evaluations at the first available refueling outage after the requested 9-month due date.

2. Reasonable assurance of operability exists. The deferred field work is confirmatory as opposed to corrective. Drawing reviews will be completed within the schedule requested in the GL. These drawing reviews will provide a strong basis for performing gas intrusion vulnerability evaluations, consistent with the principle of reasonable assurance.

Confirmatory walkdowns in accessible areas will provide the additional supporting basis for the adequacy of the evaluation. Discrepancies discovered by walkdown or survey in accessible areas of any unit will be evaluated for extent of condition on the remaining two units on an expedited basis. As walkdown and survey results are obtained, and the need for corrective actions is identified, the principle of reasonable assurance will be continually assessed.

Based on the above considerations, the licensee stated that they have a high degree of confidence in Oconee's current gas management practices supported by operating experience, current testing practices, and past corrective actions that have been performed to manage gas accumulation issues. As such, the licensee concluded that completing performance of walkdowns and surveys on portions of the subject piping systems that require refueling outages and subsequent evaluations outside of the requested 9-month timeframe is an acceptable alternative course of action.

3. NRC Staff Assessment The NRC staff finds that, with the exception of the clarifications and associated requests discussed below, that the licensees proposed alternative course of action is acceptable based on the above-described operating experience, testing, procedures and corrective actions associated with managing gas accumulation at Oconee Nuclear Station, Units 1, 2, and 3.

The NRC staff notes where the licensees 3-month submittal dated May 8, 2008, does not clearly describe the content and/or schedule for the 9-month submittals. Specifically, although the submittal states that the licensee will complete the drawing reviews and procedure reviews for the systems in the GL scope and provide results of completed evaluations within the 9-month response time (October 11, 2008), it is not clear if the licensee will perform verifications (surveys and walkdowns) of the accessible portions piping and report the results of the verifications by the reporting time.

The NRC staff requests the licensee to submit the information requested in GL 2008-01 as follows:

(1) 9-Month Initial Submittal - For the portions of the subject systems that are accessible prior to the Oconee Nuclear Station, Units 1, 2, and 3, refueling outage, provide all GL requested information to the NRC by October 11, 2008.

(2) 9-Month Supplemental (Post-Outage) Submittals - Except for the long-term items described below, provide all remaining GL requested information for the subject systems to the NRC within 90 days of the end of each of the fall 2009, fall 2008, and spring 2009 refueling outages at Oconee Nuclear Station, Units 1, 2, and 3, respectively.

For each of these two submittals (the 9-month initial and supplemental submittals), and consistent with the information requested in the GL, the licensees should provide: (1) a description of the results of evaluations that were performed in response to the GL; (2) a description of all corrective actions that the licensee determined were necessary; and (3) a statement regarding which corrective actions were completed, the schedule for completing the remaining corrective actions, and the basis for that schedule.

The NRC staff noted that the licensees submittal dated May 8, 2008, did not mention other potential long-term actions that are identified in the GL. For instance, the industry is assessing whether it is necessary to perform pump testing to determine the allowable limits on ingested gas volume in pump suctions, as well as the need to develop an analysis capability to adequately predict void movement (entrapped gas) from piping on the suction side of the pumps into the pumps. It is unlikely this industry effort will be complete for the 9-month initial or supplemental submittals. Further, technical specification changes may be necessary to reflect the improved understanding achieved during response to the GL, but these cannot be fully developed for the 9-month initial or supplemental submittals. A Technical Specifications Task Force traveler may provide a generic example that can be adopted by licensees. The NRC staff requests that the licensee address in its 9-month submittal how it plans to track such long-term actions (e.g., Corrective Action Program and/or commitment tracking). The NRC plans to perform follow-up inspections of licensee responses to GL 2008-01 at all plants using a Temporary Instruction inspection procedure.

ASSESSMENT OF 3-MONTH RESPONSE TO GENERIC LETTER 2008-01 MCGUIRE NUCLEAR STATION, UNITS 1 AND 2 DOCKET NOS. 50-369 AND 50-370

1. Background

On January 11, 2008, the Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems (Agencywide Documents Access and Management System (ADAMS) Accession No. ML072910759). The GL requested licensees to submit information to demonstrate that the emergency core cooling, decay heat removal, and containment spray systems (hereinafter referred to as the subject systems) are in compliance with the current licensing and design bases and applicable regulatory requirements, and that suitable design, operational, and testing control measures are in place for maintaining this compliance.

Specifically, the GL requested licensees to provide: (1) a description of the results of evaluations that were performed in response to the GL; (2) a description of all corrective actions that the licensee determined were necessary; and (3) a statement regarding which corrective actions were completed, the schedule for completing the remaining corrective actions, and the basis for that schedule.

In accordance with Section 50.54(f) of Title 10 of the Code of Federal Regulations (10 CFR),

GL 2008-01 required that each licensee submit the requested information within 9 months (hereinafter referred to as the 9-month submittal) of the date of the GL. The GL also stated that if a licensee cannot meet the requested 9-month response date, the licensee is required to provide a response within 3 months (hereinafter referred to as the 3-month submittal) of the date of the GL, describing the alternative course of action it proposes to take, including the basis for the acceptability of the proposed alternative course of action.

2. Licensees Proposed Alternative Course of Action By letter dated May 8, 2008, Duke Energy Carolinas, LLC (the licensee) submitted a 3-month response to GL 2008-01 for McGuire Nuclear Station, Units 1 and 2. The licensee stated they cannot meet the requested 9-month schedule for submitting the requested information because field verifications (surveys and walkdowns) of some segments of piping for the GL subject systems cannot be completed because some of the piping is located in areas which are inaccessible during power operation due to location inside containment or in high radiation areas. The following portions of these systems will not be accessible until the next refueling outage for each unit:

1. safety injection system cold and hot leg injection piping inside containment;

2. chemical and volume control system cold leg injection piping inside containment;

3. residual heat removal system cold and hot leg injection piping inside containment; and,

4. residual heat removal suction piping from the hot legs inside containment Enclosure 2

The licensee also stated that the drawing reviews and procedure reviews for the systems in the GL scope and results of completed evaluations will be completed during the 9-month timeframe prescribed in the GL (i.e., by October 11, 2008). As an alternative course of action, the licensee plans to complete the remaining field verifications during the first available refueling outage which is presently scheduled for Unit 1 in the fall of 2008, and for Unit 2 in the fall of 2009. The licensees letter dated May 8, 2008, listed the following commitments for the McGuire Nuclear Station, Units 1 and 2:

1. Submit a supplemental response to the NRC documenting the Unit 1 field verifications and any impact on the GL 2008-01 response as a result of these evaluations within 90 days following the end of the fall 2008 refueling outage.

2. Submit a supplemental response to the NRC documenting the Unit 2 field verifications and any impact on the GL 2008-01 response as a result of these evaluations within 90 days following the end of the fall 2009 refueling outage.

The licensee stated that the alternative course of action is acceptable based on the following:

1. The scope of deferred evaluation activities is small. The alternative course of action provides for completion of evaluations in three of the four areas of concern in accordance with the schedule required by the GL. In the fourth area, only those evaluation activities involving field verifications are deferred. Those deferrals provide for completion of these evaluations at the first available refueling outage after the requested 9-month due date.

2. Reasonable assurance of operability exists. The deferred field work is confirmatory as opposed to corrective. Drawing reviews will be completed within the schedule requested in the GL. These drawing reviews will provide a strong basis for performing gas intrusion vulnerability evaluations, consistent with the principle of reasonable assurance.

Confirmatory walkdowns in accessible areas will provide the additional supporting basis for the adequacy of the evaluation. Discrepancies discovered by walkdown or survey in accessible areas of any unit will be evaluated for extent of condition on the remaining unit on an expedited basis. As walkdown and survey results are obtained, and the need for corrective actions is identified, the principle of reasonable assurance will be continually assessed.

Based on the above considerations, the licensee stated that they have a high degree of confidence in McGuire's current gas management practices supported by operating experience, current testing practices, and past corrective actions that have been performed to manage gas accumulation issues. As such, the licensee concluded that completing performance of walkdowns and surveys on portions of the subject piping systems that require refueling outages and subsequent evaluations outside of the requested 9-month timeframe is an acceptable alternative course of action.

3. NRC Staff Assessment The NRC staff finds that, with the exception of the clarifications and associated requests discussed below, that the licensees proposed alternative course of action is acceptable based

on the above-described operating experience, testing, procedures, and corrective actions associated with managing gas accumulation at McGuire Nuclear Station, Units 1 and 2.

The NRC staff notes where the licensees 3-month submittal dated May 8, 2008, does not clearly describe the content and/or schedule for the 9-month submittals. Specifically, although the submittal states that the licensee will complete the drawing reviews and procedure reviews for the systems in the GL scope and provide results of completed evaluations within the 9-month response time (October 11, 2008), it is not clear if the licensee will perform verifications (surveys and walkdowns) of the accessible portions piping and report the results of the verifications by the reporting time.

The NRC staff requests the licensee to submit the information requested in GL 2008-01 as follows:

(1) 9-Month Initial Submittal - For the portions of the subject systems that are accessible prior to the McGuire Nuclear Station Unit 1 fall 2008 and Unit 2 fall 2009, refueling outages, provide all GL requested information to the NRC by October 11, 2008.

(2) 9-Month Supplemental (Post-Outage) Submittals - Except for the long-term items described below, provide all remaining GL requested information for the subject systems to the NRC within 90 days following the end of each of the fall 2008 and fall 2009 refueling outages at McGuire Nuclear Station, Unit 1 and 2, respectively.

For each of these two submittals (the 9-month initial and supplemental submittals), and consistent with the information requested in the GL, the licensees should provide: (1) a description of the results of evaluations that were performed in response to the GL; (2) a description of all corrective actions that the licensee determined were necessary; and (3) a statement regarding which corrective actions were completed, the schedule for completing the remaining corrective actions, and the basis for that schedule.

The NRC staff noted that the licensees submittal dated May 8, 2008, did not mention other potential long-term actions that are identified in the GL. For instance, the industry is assessing whether it is necessary to perform pump testing to determine the allowable limits on ingested gas volume in pump suctions, as well as the need to develop an analysis capability to adequately predict void movement (entrapped gas) from piping on the suction side of the pumps into the pumps. It is unlikely this industry effort will be complete for the 9-month initial or supplemental submittals. Further, technical specification changes may be necessary to reflect the improved understanding achieved during response to the GL, but these cannot be fully developed for the 9-month initial or supplemental submittals. A Technical Specifications Task Force traveler may provide a generic example that can be adopted by licensees. The NRC staff requests that the licensee address in its 9-month submittal how it plans to track such long-term actions (e.g., Corrective Action Program and/or commitment tracking). The NRC plans to perform follow-up inspections of licensee responses to GL 2008-01 at all plants using a Temporary Instruction inspection procedure.

ASSESSMENT OF 3-MONTH RESPONSE TO GENERIC LETTER 2008-01 CATAWBA NUCLEAR STATION, UNIT NO. 2 DOCKET NO. 50-413 AND 414

1. Background

On January 11, 2008, the Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems (Agencywide Documents Access and Management System (ADAMS) Accession No. ML072910759). The GL requested licensees to submit information to demonstrate that the emergency core cooling, decay heat removal, and containment spray systems (hereinafter referred to as the subject systems) are in compliance with the current licensing and design bases and applicable regulatory requirements, and that suitable design, operational, and testing control measures are in place for maintaining this compliance.

Specifically, the GL requested licensees to provide: (1) a description of the results of evaluations that were performed in response to the GL; (2) a description of all corrective actions that the licensee determined were necessary; and (3) a statement regarding which corrective actions were completed, the schedule for completing the remaining corrective actions, and the basis for that schedule.

In accordance with Section 50.54(f) of Title 10 of the Code of Federal Regulations (10 CFR),

GL 2008-01 required that each licensee submit the requested information within 9 months (hereinafter referred to as the 9-month submittal) of the date of the GL. The GL also stated that if a licensee cannot meet the requested 9-month response date, the licensee is required to provide a response within 3 months (hereinafter referred to as the 3-month submittal) of the date of the GL, describing the alternative course of action it proposes to take, including the basis for the acceptability of the proposed alternative course of action.

2. Licensees Proposed Alternative Course of Action By letter dated May 8, 2008, Duke Energy Carolinas, LLC (the licensee) submitted a 3-month response to GL 2008-01 for Catawba Nuclear Station, Units 1 and 2 The licensee stated actions requested by the GL will be completed for Unit 1 by October 11, 2008. However, for Unit 2. The licensee stated it cannot meet the requested 9-month schedule for submitting the requested information because field verifications (surveys and walkdowns) of some segments of piping for the GL subject systems and because some of the piping is located in areas which are inaccessible during power operation due to location inside containment or in high radiation areas. The following portions of these systems will not be accessible until the next refueling outage for Unit 2:

1. safety injection system cold and hot leg injection piping inside containment

2. chemical and volume control system cold leg injection piping inside containment

3. residual heat removal system cold and hot leg injection piping inside containment

4. residual heat removal suction piping from the hot leg(s) inside containment Enclosure 3

The licensee also stated that the drawing reviews and procedure reviews for the systems in the GL scope and results of completed evaluations will be completed during the 9-month timeframe prescribed in the GL (i.e., by October 11, 2008. As an alternative course of action, the licensee plans to complete the remaining field verifications during the first available refueling outage which is presently scheduled for spring 2009. The licensees letter dated May 8, 2008, listed the following commitments for the Catawba Nuclear Station, Unit 2:

1. Submit a supplemental response to the NRC documenting the Unit 2 field verifications and any impact on the GL 2008-01 response, as a result, of these evaluations within 90 days following the end of the next refueling outage scheduled for the spring 2009.

2. Submit supplemental response to the NRC documenting the Unit 1 field verifications and any impact on the GL 2008-01 response as a result of these evaluations within 90 days following the end of the fall 2009 refueling outage.

The licensee stated that the alternative course of action is acceptable based on the following:

1. The scope of deferred evaluation activities is small. The alternative course of action provides for completion of evaluations in three of the four areas of concern in accordance with the schedule required by the GL. In the fourth area, only those evaluation a field verifications are deferred. Those deferrals provide for completion of these evaluations at the first available refueling outage after the requested 9-month due date.

2. Reasonable assurance of operability exists. The deferred field work is confirmatory as opposed to corrective. Drawing reviews will be completed within the schedule requested in the GL. These drawing reviews will provide a strong basis for performing gas intrusion vulnerability evaluations, consistent with the principle of reasonable assurance.

Confirmatory walkdowns in accessible areas will provide the additional supporting basis for the adequacy of the evaluation. Discrepancies discovered by walkdown or survey in accessible areas of any unit will be evaluated for extent of condition on the remaining unit on an expedited basis. As walkdown and survey results are obtained, and the need for corrective actions is identified, the principle of reasonable assurance will be continually assessed.

Based on the above considerations, the licensee stated that they have a high degree of confidence in Catawba's current gas management practices supported by operating experience, current testing practices, and past corrective actions that have been performed manage gas accumulation issues. As such, the licensee concluded that completing performance of walkdowns and surveys on portions of the subject outside of the requested 9-month timeframe is an acceptable alternative course of action.

3. NRC Staff Assessment The NRC staff finds that, with the exception of the clarifications and associated requests discussed below, that the licensees proposed alternative course of action is acceptable based on the above-described operating experience, testing, procedures, and corrective actions associated with managing gas accumulation at Catawba Nuclear Station, Unit 2.

The NRC staff notes where the licensees 3-month submittal dated May 8, 2008, does not clearly describe the content and/or schedule for the 9-month submittals. Specifically, although the submittal states that the licensee will complete the drawing reviews and procedure reviews for the systems in the GL scope and provide results of completed evaluations within the 9-month response time (October 11, 2008), it is not clear if the licensee will perform verifications (surveys and walkdowns) of the accessible portions piping and report the results of the verifications by the reporting time.

The NRC staff requests the licensee to submit the information requested in GL 2008-01 as follows:

(1) 9-Month Initial Submittal - For the portions of the subject systems that are accessible prior to the Catawba Nuclear Station, Unit 2, spring 2009 refueling outage, provide all GL requested information to the NRC by October 11, 2008.

(2) 9-Month Supplemental (Post-Outage) Submittal - Except for the long-term items described below, provide all remaining GL requested information for the subject systems to the NRC within 90 days following the end of the next refueling outage scheduled for spring 2009 at Catawba Nuclear Station, Unit 2.

For each of these two submittals (the 9-month initial and supplemental submittals), and consistent with the information requested in the GL, the licensees should provide: (1) a description of the results of evaluations that were performed in response to the GL; (2) a description of all corrective actions that the licensee determined were necessary; and (3) a statement regarding which corrective actions were completed, the schedule for completing the remaining corrective actions, and the basis for that schedule.

The NRC staff noted that the licensees submittal dated May 8, 2008, did not mention other potential long-term actions that are identified in the GL. For instance, the industry is assessing whether it is necessary to perform pump testing to determine the allowable limits on ingested gas volume in pump suctions, as well as the need to develop an analysis capability to adequately predict void movement (entrapped gas) from piping on the suction side of the pumps into the pumps. It is unlikely this industry effort will be complete for the 9-month initial or supplemental submittals. Further, technical specification changes may be necessary to reflect the improved understanding achieved during response to the GL, but these cannot be fully developed for the 9-month initial or supplemental submittals. A Technical Specifications Task Force traveler may provide a generic example that can be adopted by licensees. The NRC staff requests that the licensee address in its 9-month submittal how it plans to track such long-term actions (e.g., Corrective Action Program and/or commitment tracking). The NRC plans to perform follow-up inspections of licensee responses to GL 2008-01 at all plants using a Temporary Instruction inspection procedure.