ML081000213
| ML081000213 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 04/10/2008 |
| From: | Mark Kowal NRC/NRR/ADRO/DORL/LPLI-1 |
| To: | Entergy Nuclear Operations |
| Boska J, NRR, 301-415-2901 | |
| References | |
| GL-04-002, GSI-191, TAC MC4689, TAC MC4690 | |
| Download: ML081000213 (9) | |
Text
April 10, 2008 Vice President, Operations Entergy Nuclear Operations, Inc.
Indian Point Energy Center 450 Broadway, GSB P.O. Box 249 Buchanan, NY 10511-0249
SUBJECT:
INDIAN POINT NUCLEAR GENERATING UNIT NOS. 2 AND 3 - APPROVAL OF REVISED EXTENSION REQUEST FOR CORRECTIVE ACTIONS REQUIRED BY GENERIC LETTER 2004-02 (TAC NOS. MC4689 AND MC4690)
Dear Sir or Madam:
In a letter dated March 28, 2008, Agencywide Document Access and Management System (ADAMS) accession number ML080990085, Entergy Nuclear Operations, Inc. (Entergy) submitted a request for an additional extension to the completion deadline for the corrective actions required by Generic Letter (GL) 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized Water Reactors for the Indian Point Nuclear Generating Unit Nos. 2 and 3 (IP2 and IP3). In a letter dated November 20, 2007, ADAMS accession number ML073230169, the Nuclear Regulatory Commission (NRC) previously issued an extension to IP2 until the completion of the IP2 spring 2008 refueling outage. In a letter dated December 20, 2007, ADAMS accession number ML073510242, the NRC previously issued an extension to IP3 until June 30, 2008. This revised extension would allow Entergy until October 31, 2008, to perform the remaining modifications and licensing activities necessary to achieve full compliance with GL 2004-02 at IP2 and IP3.
The NRC staff has evaluated the information in your revised request and determined that it is acceptable to extend the completion date for the remaining modifications and licensing activities as described in the referenced letter, until October 31, 2008. The results of the NRC staffs evaluation of this request are enclosed.
Please contact the Indian Point Project Manager, John Boska, at (301) 415-2901 if you have any questions on this issue.
Sincerely,
/RA/
Mark G. Kowal, Chief Plant Licensing Branch I-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-247 and 50-286
Enclosure:
As stated cc w/encl: See next page
ML081000213 OFFICE LPL1-1/PM LPL1-1/LA SSIB/BC LPL1-1/BC NAME JBoska SLittle LWhitney for MScott MKowal DATE 4/10/08 4/9/08 4/9/08 4/10/08
DATED: April 10, 2008 INDIAN POINT NUCLEAR GENERATING UNIT NOS. 2 AND 3 - APPROVAL OF REVISED EXTENSION REQUEST FOR CORRECTIVE ACTIONS REQUIRED BY GENERIC LETTER 2004-02 PUBLIC RidsNrrDorlLpl1-1 RidsNrrPMJBoska RidsOGCMailCenter LPL1-1 Reading File RidsNrrLASLittle RidsAcrsAcnw&mMailCenter RidsNrrDorlDpr RidsRgn1MailCenter MScott, NRR/SSIB cc: Plant Mailing List
Indian Point Nuclear Generating Unit Nos. 2 & 3 cc:
Senior Vice President Entergy Nuclear Operations, Inc.
P.O. Box 31995 Jackson, MS 39286-1995 Vice President Oversight Entergy Nuclear Operations, Inc.
P.O. Box 31995 Jackson, MS 39286-1995 Senior Manager, Nuclear Safety &
Licensing Entergy Nuclear Operations, Inc.
P.O. Box 31995 Jackson, MS 39286-1995 Senior Vice President and COO Entergy Nuclear Operations, Inc.
440 Hamilton Avenue White Plains, NY 10601 Assistant General Counsel Entergy Nuclear Operations, Inc.
440 Hamilton Avenue White Plains, NY 10601 Manager, Licensing Entergy Nuclear Operations, Inc.
Indian Point Energy Center 450 Broadway, GSB P.O. Box 249 Buchanan, NY 10511-0249 Mr. Paul Tonko President and CEO New York State Energy, Research, and Development Authority 17 Columbia Circle Albany, NY 12203-6399 Mr. John P. Spath New York State Energy, Research, and Development Authority 17 Columbia Circle Albany, NY 12203-6399 Mr. Paul Eddy New York State Department of Public Service 3 Empire State Plaza Albany, NY 12223-1350 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Senior Resident Inspector=s Office Indian Point 2 U. S. Nuclear Regulatory Commission P.O. Box 59 Buchanan, NY 10511 Senior Resident Inspector=s Office Indian Point 3 U. S. Nuclear Regulatory Commission P.O. Box 59 Buchanan, NY 10511 Mr. Charles Donaldson, Esquire Assistant Attorney General New York Department of Law 120 Broadway New York, NY 10271 Mr. Raymond L. Albanese Four County Coordinator 200 Bradhurst Avenue Unit 4 Westchester County Hawthorne, NY 10532 Mayor, Village of Buchanan 236 Tate Avenue Buchanan, NY 10511 Mr. Jim Riccio Greenpeace 702 H Street, NW Suite 300 Washington, DC 20001
Indian Point Nuclear Generating Unit Nos. 2 & 3 cc:
Mr. Phillip Musegaas Riverkeeper, Inc.
828 South Broadway Tarrytown, NY 10591 Mr. Mark Jacobs IPSEC 46 Highland Drive Garrison, NY 10524 Mr. Sherwood Martinelli FUSE USA via email
INDIAN POINT NUCLEAR GENERATING UNIT NOS. 2 AND 3 GENERIC SAFETY ISSUE (GSI)-191/GENERIC LETTER (GL) 2004-02 EXTENSION REQUEST APPROVAL By letter dated March 28, 2008, Entergy Nuclear Operations, Inc. (Entergy or the licensee),
requested an additional extension to the Nuclear Regulatory Commission (NRC) Generic Letter (GL) 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors corrective action due dates for Indian Point Nuclear Generating Unit Nos. 2 and 3 (IP2 and IP3). The intent of these extensions is to allow Entergy additional time to perform the final testing and analysis, potential resultant facility modifications, and all licensing activities to address compliance with GL 2004-02.
Previously, the NRC staff had approved an extension for IP2 GL 2004-02 corrective actions from the GL 2004-02 due date of December 31, 2007, until restart following completion of the IP2 spring 2008 refueling outage (NRC letter dated November 20, 2007, Agencywide Document Access and Management System (ADAMS) accession number ML073230169). Similarly, the corrective actions due date for IP3 was extended to June 30, 2008, (NRC letter dated December 20, 2007, ADAMS accession number ML073510242).
Entergy stated in their March 28, 2008, letter that the request for an additional extension for both units is due to developments in the test and analysis areas that include debris and chemical testing, debris erosion and capture, downstream effects, and application of the head loss correlation. The licensee explained that a failure of a test loop resulted in the need for a partial repeat of a 30-day chemical effects test causing significant delays, and that the other developments will result in re-analysis of debris transport, strainer qualification and associated evaluations.
Entergy stated in its letter that the facility modifications described in the earlier extension requests will be installed as scheduled, as discussed in the extension approval letters cited above.
The NRC staff has based its reviews for granting extensions to the due date for completion of GL 2004-02 corrective actions on the criteria stated in SECY-06-0078. Specifically, an extension may be granted if:
the licensee has a plant-specific technical/experimental plan with milestones and schedule to address outstanding technical issues with enough margin to account for uncertainties, and the licensee identifies mitigative measures to be put in place prior to December 31, 2007, and adequately describes how these mitigative measures will minimize the risk of degraded emergency core cooling system (ECCS) and containment spray system (CSS) functions during the extension period.
The SECY also states that for proposed extensions beyond several months, a licensees request will more likely be accepted if the proposed mitigative measures include temporary physical improvements to the ECCS sump or materials inside containment to better ensure a high level of ECCS sump performance.
Enclosure With regard to the first extension criterion, Entergy has provided a plant-specific technical/experimental plan, with milestones and schedules, to complete the GL 2004-02 corrective actions. While the licensee proposed plan for the remaining corrective actions is summarized below, the completed activities have been previously summarized and referenced in the previous IP2 and IP3 NRC extension approval letters cited above.
In light of the new developments, and in order to meet the regulatory requirements, Entergy stated that it has scheduled the following activities.
Hardware Installation of buffer replacement modification packages (IP2 and IP3). IP2 has an approved buffer replacement license amendment and that activity is being conducted during the spring 2008 refueling outage. IP3 buffer replacement is subject to prior NRC approval, and the license amendment request was submitted to the NRC on February 28, 2008. This buffer change will be implemented within 60 days of the approval of the license amendment request or by June 30, 2008, whichever is later.
Installation of an IP2 Vapor Containment (VC) sump strainer extension (additional strainer modules) outside the crane wall and miscellaneous other modifications. Entergy stated that it plans to install these modifications during the IP2 spring 2008 refueling outage.
Analysis Revision to net positive suction head available (NPSHA) analyses (IP2 and IP3), which will be performed concurrent with post-strainer testing strainer design certifications.
Revision to debris transport analyses (IP2 and IP3), scheduled for completion by May 28, 2008 (IP2) and July 9, 2008 (IP3).
Strainer head loss qualification for debris and chemical effects (IP2 and IP3), scheduled for completion by July 17, 2008 (IP2), and August 27, 2008 (IP3).
In-vessel and ex-vessel downstream effects re-evaluations (IP2 and IP3). The ex-vessel re-evaluation will be conducted in accordance with WCAP 16406-P Rev. 1, and is planned to be completed by July 8, 2008 for both units. The in-vessel evaluation for both units will be conducted in accordance with WCAP-16793 and is planned to be completed by May 14, 2008.
Resolution of NRC audit open items and supporting activities (IP2 and IP3), planned to be completed prior to strainer head loss qualification.
Licensing NRC approval of a passive failure-related license amendment request (IP2 and IP3) as discussed in the March 28, 2008, Entergy letter. Entergy plans to implement the passive failure-related licensing basis changes prior to October 31, 2008. However, implementation is contingent upon prior NRC approval of the license amendment request with sufficient time to implement the change. In order to support the October 31, 2008, date, the licensee stated that the NRC would have to approve the amendment request by August 31, 2008. The license amendment request was submitted on March 13, 2008.
With regard to the second extension criterion, the licensee has stated that modifications, mitigation measures, compensatory measures, and/or favorable conditions are in effect at IP2 and IP3, minimizing the risk of degraded ECCS and CSS functions during the extension period.
The NRC staff evaluations of the previous extension requests concluded that Entergy had put mitigation measures in place at IP2 and IP3 to adequately reduce risk for the previous requested extension periods (spring 2008 for IP2 and June 30, 2008, for IP3) as stated in the NRC extension approval letters cited above.
In its March 28, 2008, letter Entergy stated that the mitigation measures and unit-specific conditions evaluated by the staff in the previous extension requests, which include strainer replacement, have remained unchanged. Entergy stated that it will implement the following additional measures for the requested extension period; Indian Point Unit 2
- 1. Containment sump buffer replacement.
- 2. Installation of screens on certain crane wall penetrations.
- 3. Installation of grating on the containment sump trench.
- 4. Screen modification on the LT-938 sump level instrument housing.
- 5. Installation of containment sump extension (additional strainer modules) in the annulus outside the crane wall that will complete the strainer installation.
Indian Point Unit 3
- 1. Containment sump buffer replacement.
The licensee also noted other favorable factors that are applicable to IP2 and IP3. These include a compartmentalized containment that reduces debris transport, a delay of 20-30 minutes after a loss-of-coolant accident occurs before recirculation begins (which would allow some debris to settle to the containment floor), and a containment coatings inspection and evaluation program.
Entergy noted that with the installation of the new strainers and other associated modifications, as described above, there has been a significant reduction in the vulnerability to debris blockage and downstream effects as compared to the original physical configuration. This was stated to be due to the significant increase in strainer surface area, the elimination of potential upstream flow chokepoints, and the reduction of the debris strainer bypass term due to the bypass steel mesh filter in each strainer module. It was also stated that there will be a further reduction in vulnerability following buffer replacement in both units, which would reduce the amount of chemical precipitates generated in the containment and, in turn, reduce head loss across strainer fiber beds. It was further stated that installation of the IP2 containment sump strainers outside the crane wall during the spring 2008 outage will reduce vulnerability by enhancing the back-up or secondary emergency sump capability of the VC sump.
A factor which also reduces vulnerability increase is the fact that there are two independent sumps in each units containment, the internal recirculation sump and the smaller VC sump.
The internal recirculation sump is the primary sump used for accident mitigation, and the VC sump provides backup capability to allow for the effects of a passive failure.
A further factor which reduces vulnerability is the availability of four low head pumps available for accident mitigation, any one of which can provide complete accident mitigation: two internal recirculation (IR) pumps that draw from the internal recirculation sump, and two residual heat removal pumps that draw from the VC sump.
A final factor that reduces vulnerability is that the new strainer design reduces the risk of downstream component blockage because the new design has small diameter holes (3/32 inch) and a bypass eliminator steel mesh filter which reduces the total quantity of fiber that could bypass the strainer.
The NRC staff believes that Entergy has a reasonable plan for IP2 and IP3 that should result in the installation of final GL 2004-02 corrective actions that provide acceptable strainer function with adequate margin for uncertainties. Furthermore, the NRC has concluded that Entergy has put mitigation measures in place at IP2 and IP3 to reduce vulnerability to debris blockage and downstream effects for the proposed extension period. Based on the licensee having satisfactorily addressed the NRC GL 2004-02 due date extension criteria as discussed above, the NRC staff finds it is acceptable to extend the completion date for GL 2004-02 corrective actions for IP2 and IP3 to October 31, 2008. Implementation of the IP3 buffer change and the change in the passive single failure licensing basis for IP2 and IP3 are contingent on NRC approval of the licensees license amendment requests.
Entergy should complete its remaining GL 2004-02 corrective actions as discussed above.
Approval of these extensions to the GL 2004-02 corrective action due dates for IP2 and IP3 shall not be construed as approval of the operating license amendment requests discussed above.