ML101260166

From kanterella
Jump to navigation Jump to search

E-mail from R. Guzman to J. Dosa Acceptance Review Revised Questions for License Amendment Requesting 14 Day Completion Time Extension for Inoperable EDG
ML101260166
Person / Time
Site: Nine Mile Point Constellation icon.png
Issue date: 05/06/2010
From: Richard Guzman
Division of Operating Reactor Licensing
To: Dosa J, Richard Guzman, Vandeputte D
Nine Mile Point, Office of Nuclear Reactor Regulation
Guzman R, NRR/DORL, 415-1030
References
TAC ME3736
Download: ML101260166 (6)


Text

From: Guzman, Richard Sent: Thursday, May 06, 2010 11:25 AM To: Guzman, Richard; 'Dosa, John J'; 'Vandeputte, Dennis E'

Subject:

RE: LIC-109 Non-Acceptance Determination w/Opportunity to Supplement -

ME3736 Nine Mile Point 2 - Inop DG 14-day Completion Time Extension (application dated 3/30/10)

John, As we discussed, see revised question nos. 1 and 8 (in bold) below. No. 1 was modified to specify Rev. 2 as the applicable RG 1.200 for providing PRA quality information needed for fire and seismic risk models. The rationale from the staff is that after reviewing RG 1.200 and the associated RIS 2007-06 which discusses implementation, Rev. 2 of RG 1.200 was delayed for implementation for one year only for the purpose of requiring the use of endorsed standards.

The high level requirements found in Section 1.2 were revised in Rev. 2, and these reflect the information needed by the staff to review the PRA. Therefore, the staff requests that the submitted information be consistent w/Rev. 2 of RG 1.200 sections 1.2.4 and 1.2.6, although the submitted information does not have to provide NMPNS's assessment of the models against the endorsed standards. Question No. 8 was revised to indicate that staff's concerns for electric grid stability/performance concerns were considered as part of this additional information need.

Please advise a time/date you can support a follow-up call to discuss these revised questions.

Early next week works for us at this time.

Thanks, Rich Guzman Sr. Project Manager NRR/DORL US NRC 301-415-1030 Richard.Guzman@nrc.gov

DRAFT Rev.1 -------

PRA Licensing Review

1. The submittal identifies that fire and seismic risk are included in the PRA model. A single paragraph referring to the IPEEE submittal and to the NRC IPEEE evaluation is provided, along with a table of the NRC review comments and their disposition from the IPEEE. The purpose of the IPEEE and the NRC Research Office staff evaluation was to identify significant plant vulnerabilities, not to establish that the analyses were state-of-the art risk analyses to support licensing actions. This level of quality is not acceptable to support a risk-informed TS change. The licensee will need to submit PRA quality information on its fire and seismic risk models consistent with RG 1.200, Revision 2, Section 1.2.4 (fires) and 1.2.6 (seismic) to demonstrate that these quantitative models are adequate for this application. The licensee should also submit confirmation that the

existing fire and seismic models, stated to be based on the IPEEE, still adequately reflect the current plant configuration with regards to mitigation of these events.

2. Other plant hazards are not identified as included in the quantitative risk analyses, nor are qualitative dispositions provided to determine that the risk from these hazard groups is insignificant. This is inconsistent with RG 1.174 which requires all hazards to be addressed.

The licensee will need to address these external hazards unless they are included in the quantitative results; if so, then the technical adequacy of these PRA models will then need to be addressed per RG 1.200 Section 1.2.

3. The evaluation of the internal events PRA model using RG 1.200 and the applicable PRA standard does not identify the relevant capability category(ies) associated with this application, nor is the capability category(ies) of the PRA model identified in the submittal. This is inconsistent with RG 1.200 Section 4.2. The licensee will need to supplement their submittal to address the capability category(ies) of the standard applicable to this analysis.
4. There is no statement regarding any permanent plant changes implemented but not incorporated into the PRA model used to support this risk analysis. This is inconsistent with RG 1.200 Section 4.2. The licensee will need to supplement their submittal to address this issue.
5. The submittal makes extensive commitments to Tier 2 equipment restrictions (Section 3.2.5) which are credited in the risk analyses. These restrictions are to be incorporated into plant procedures and the TS bases, but not into the TS action requirements. There are no sensitivity analyses provided to allow the staff to determine which, if any, of these restrictions are critical to the acceptance of this change. The licensee will need to provide appropriate sensitivity analyses to permit staff review of the acceptability of these restrictions and their control in procedures and TS bases rather than in the TS actions.
6. The risk analyses are dependent upon the once-per-two-year use of the extended CTs, but there is no justification as to why this assumption is valid. The licensee proposes to control voluntary use of the CT to once- per-two-years, but this is to be addressed in the TS bases, not in the TS action. Emergent repairs may result in additional use of the extended CT. The licensee will need to provide a technical justification for this assumption, and will need to provide sensitivity studies to address emergent repair use of the extended CT considering the increased probability of common cause failures (consistent with RG 1.177 Appendix A).

Electrical Engineering Review

7. In the LAR, the licensee did not provide adequate justification for amending TS Section 3.8.1 to extend the Completion time for an inoperable Division 1 or 2 diesel generator from 72 hours3 days <br />0.429 weeks <br />0.0986 months <br /> to 14 days. Specifically, the licensee states " the 2-year DG inspections (which typically require 5 days to complete) and the 6-year DG overhauls (which typically require 7 days to complete)."

Provide the basis for the proposed extended Completion Time of 14 days.

8. It appears that the capacity of the proposed alternate AC power source to replace the inoperable EDG (Division 1 or 2) is not adequate to support a LOOP event with a unit trip.

Considering the changes in electric grid performance post-deregulation, the duration of loss of offsite power events has increased and that the probability of a LOOP as a consequence of a reactor trip has increased. As a deterministic measure to ensure adequate defense in depth given the changes in the electric grid performance post-deregulation, the staff requires the replacement power source has adequate capacity of

handling station blackout and loss-of-offsite power loads, to supplement the existing EDGs during the extended 14-day AOT. Provide justification to demonstrate that the proposed diesel is adequate to maintain the defense-in-depth philosophy of the emergency power system.


DRAFT Rev.1 -------

From: Guzman, Richard Sent: Wednesday, April 28, 2010 2:18 PM To: Dosa, John J

Subject:

LIC-109 Non-Acceptance Determination w/Opportunity to Supplement - ME3736 Nine Mile Point 2 - Inop DG 14-day Completion Time Extension (application dated 3/30/10)

John, By letter dated March 30, 2010, Nine Mile Point Nuclear Station, LLC (NMPNS) submitted a license amendment request (LAR) for Nine Mile Point, Unit No. 1 (NMP2). The purpose of this e-mail is to provide the results of the NRC staff's acceptance review. The acceptance review was performed to determine if there is sufficient technical information in scope and depth to allow the NRC staff to complete its detailed technical review.

The NRC staff has reviewed NMPNS's LAR and has found it unacceptable for review with the opportunity for the licensee to supplement. We would like to set up a conference call to discuss the identified information insufficiencies which is provided below in draft form. Please let me know your availability for a teleconference for sometime next week but no later than 5/5/10. I'd like to propose Tuesday anytime between 9a - 11a or 1p - 3p for the call. Please contact me if you have any questions.

Thanks, Rich Guzman Sr. Project Manager NRR/DORL US NRC 301-415-1030 Richard.Guzman@nrc.gov

DRAFT----------------

PRA Licensing Review

1. The submittal identifies that fire and seismic risk are included in the PRA model. A single paragraph referring to the IPEEE submittal and to the NRC IPEEE evaluation is provided, along with a table of the NRC review comments and their disposition from the IPEEE. The purpose of the IPEEE and the NRC Research Office staff evaluation was to identify significant plant

vulnerabilities, not to establish that the analyses were state-of-the art risk analyses to support licensing actions. This level of quality is not acceptable to support a risk-informed TS change.

The licensee will need to submit PRA quality information on its fire and seismic risk models consistent with RG 1.200 Section 1.2.4 (fires) and 1.2.6 (seismic) to demonstrate that these quantitative models are adequate for this application. The licensee should also submit confirmation that the existing fire and seismic models, stated to be based on the IPEEE, still adequately reflect the current plant configuration with regards to mitigation of these events. The staff will be using the RG 1.200 endorsed standards to evaluate portions of the IPEEE PRA for fires relevant to this amendment request.

2. Other plant hazards are not identified as included in the quantitative risk analyses, nor are qualitative dispositions provided to determine that the risk from these hazard groups is insignificant. This is inconsistent with RG 1.174 which requires all hazards to be addressed.

The licensee will need to address these external hazards unless they are included in the quantitative results; if so, then the technical adequacy of these PRA models will then need to be addressed per RG 1.200 Section 1.2.

3. The evaluation of the internal events PRA model using RG 1.200 and the applicable PRA standard does not identify the relevant capability category(ies) associated with this application, nor is the capability category(ies) of the PRA model identified in the submittal. This is inconsistent with RG 1.200 Section 4.2. The licensee will need to supplement their submittal to address the capability category(ies) of the standard applicable to this analysis.
4. There is no statement regarding any permanent plant changes implemented but not incorporated into the PRA model used to support this risk analysis. This is inconsistent with RG 1.200 Section 4.2. The licensee will need to supplement their submittal to address this issue.
5. The submittal makes extensive commitments to Tier 2 equipment restrictions (Section 3.2.5) which are credited in the risk analyses. These restrictions are to be incorporated into plant procedures and the TS bases, but not into the TS action requirements. There are no sensitivity analyses provided to allow the staff to determine which, if any, of these restrictions are critical to the acceptance of this change. The licensee will need to provide appropriate sensitivity analyses to permit staff review of the acceptability of these restrictions and their control in procedures and TS bases rather than in the TS actions.
6. The risk analyses are dependent upon the once-per-two-year use of the extended CTs, but there is no justification as to why this assumption is valid. The licensee proposes to control voluntary use of the CT to once- per-two-years, but this is to be addressed in the TS bases, not in the TS action. Emergent repairs may result in additional use of the extended CT. The licensee will need to provide a technical justification for this assumption, and will need to provide sensitivity studies to address emergent repair use of the extended CT considering the increased probability of common cause failures (consistent with RG 1.177 Appendix A).
7. In addition to the deficiencies in PRA, it is noted that NMP2 has not proposed an alternate AC power source (AAC) to support this amendment request.

Electrical Engineering Review

8. In the LAR, the licensee did not provide adequate justification for amending TS Section 3.8.1 to extend the Completion time for an inoperable Division 1 or 2 diesel generator from 72 hours3 days <br />0.429 weeks <br />0.0986 months <br /> to 14 days. Specifically, the licensee states " the 2-year DG inspections (which typically require

5 days to complete) and the 6-year DG overhauls (which typically require 7 days to complete)."

Provide the basis for the proposed extended Completion Time of 14 days.

9. It appears that the capacity of the proposed alternate AC power source (HPCS EDG) to replace the inoperable EDG (Division 1 or 2) is not adequate to support a LOOP event with a unit trip. The NRC staff's position is that the replacement power source must have at least the same capability as the inoperable EDG (Division 1 or 2). Also, the LAR does not provide details regarding the methods and the time limitation for cross-connecting the power source to the Division 1 or 2 buses and its affect on plant shutdown. Explain why the proposed diesel is adequate to maintain the defense-in-depth philosophy of the emergency power system.

DRAFT----------------

E-mail Properties Mail Envelope Properties (F5A4366DF596BF458646C9D433EA37D7292F476A99)

Subject:

RE: LIC-109 Non-Acceptance Determination w/Opportunity to Supplement -

ME3736 Nine Mile Point 2 - Inop DG 14-day Completion Time Extension (application dated 3/30/10)

Sent Date: 5/6/2010 11:24:43 AM Received Date: 5/6/2010 11:24:43 AM From: Guzman, Richard Created By: Richard.Guzman@nrc.gov Recipients:

Richard.Guzman@nrc.gov (Guzman, Richard)

Tracking Status: None John.Dosa@cengllc.com ('Dosa, John J')

Tracking Status: None Dennis.Vandeputte@cengllc.com ('Vandeputte, Dennis E')

Tracking Status: None Post Office:

HQCLSTR01.nrc.gov Files Size Date & Time MESSAGE 30508 5/6/2010 Options Expiration Date:

Priority: olImportanceNormal

ReplyRequested: False Return Notification: False Sensitivity: olNormal Recipients received: