ML102180203: Difference between revisions

From kanterella
Jump to navigation Jump to search
(Created page by program invented by StriderTol)
(StriderTol Bot change)
 
Line 42: Line 42:
VEPCOs application dated March 30, 2010, included the aforementioned deviations from the proposed language in TSTF-425, Revision 3. The NRC staff has reviewed the proposed deviation from TSTF-425 and requests that the licensee modifies the application as described above, or develop an alternate resolution to the issue with Insert #2 as described in item 3, and including appropriate justifications.
VEPCOs application dated March 30, 2010, included the aforementioned deviations from the proposed language in TSTF-425, Revision 3. The NRC staff has reviewed the proposed deviation from TSTF-425 and requests that the licensee modifies the application as described above, or develop an alternate resolution to the issue with Insert #2 as described in item 3, and including appropriate justifications.
Please submit the response to these RAIs by September 3, 2010.                                            If you have any questions please contact me.
Please submit the response to these RAIs by September 3, 2010.                                            If you have any questions please contact me.
___________________________
V. Sreenivas, PH.D., C.P.M.,
V. Sreenivas, PH.D., C.P.M.,
Project Manager, Rm.#O8F6, LPL2-1 North Anna Power Reactors, Units 1 and 2 Division of Operating Reactor Licensing-NRR (301) 415-2597, v.sreenivas@nrc.gov
Project Manager, Rm.#O8F6, LPL2-1 North Anna Power Reactors, Units 1 and 2 Division of Operating Reactor Licensing-NRR (301) 415-2597, v.sreenivas@nrc.gov

Latest revision as of 20:23, 11 March 2020

E-mail Regarding Request for Additional Information, Risk Informed Technical Specifications Initiative 5b, TSTF-425 Revision 3
ML102180203
Person / Time
Site: North Anna  Dominion icon.png
Issue date: 08/06/2010
From: V Sreenivas
Plant Licensing Branch II
To: Heacock D
Dominion, Virginia Electric & Power Co (VEPCO)
Sreenivas V.NRR/DORL/LPL2-1 415-2597
References
Download: ML102180203 (2)


Text

From: Sreenivas, V Sent: Friday, August 06, 2010 11:44 AM To: 'david.heacock@dom.com' Cc: 'Tom Shaub'; 'david.sommers@dom.com'; Howe, Andrew; Waig, Gerald; Kulesa, Gloria

Subject:

REQUEST FOR ADDITIONAL INFORMATION: Risk Informed Technical Specifications Initiative 5b, TSTF-425 REVISION 3 By letter dated March 30, 2010, Virginia Electric and Power Company (VEPCO) requests amendments, in the form of changes to the Technical Specifications (TS) to Facility Operating License Numbers NPF-4 and NPF-7, for North Anna Power Station Units 1 and 2, respectively. The proposed amendments would modify TS by relocating specific surveillance frequencies to a licensee-controlled program with the implementation of Nuclear Energy Institute (NEI) 04-10, "Risk Informed Technical Specifications Initiative 5b, Risk-Informed Method for Control of Surveillance Frequencies." The purpose of this email is to provide the results of the U.S. Nuclear Regulatory Commission (NRC) staffs detailed technical review of this request. Please submit the following additional information to complete its detailed technical review.

REQUEST FOR ADDITIONAL INFORMATION RELATED TO AN AMENDMENT TO IMPLEMENT TSTF-425 REVISION 3 VIRGINIA ELECTRIC AND POWER COMPANYNORTH ANNA POWER STATION UNITS 1 AND 2, DOCKET No. 50-338 AND 50-339

1. In Table 1 of Attachment 2 of the submittal, the importance of each gap to this application in many instances is dispositioned simply by referring to the Nuclear Energy Institute (NEI) 04-10 requirement to assess deficiencies with sensitivity analyses. This statement alone is insufficient for the staff to find the probabilistic risk assessment (PRA) model adequate to support the application. The licensee is requested to provide its assessment of the significance of each gap to the calculation of risk increases associated with changes to surveillance frequency. This is requested for the following items in Table 1: #1, #2, #3(1), #4(1), #5, #7, #9,
  1. 10, and #17.
2. In Table 1 of Attachment 2 of the submittal, several gaps (#3, #4(1), #5, #7, #9) identify missing logic in the PRA model (inadequate scope). It is not clear to the staff how missing scope in a PRA can be addressed by sensitivity analyses. The licensee is requested to discuss how it would conduct such analyses for this application. This is requested for the following items in Table 1: #3, #4(1), #5, #7, and #9.
3. In Attachment 1, Section 2.2 item 3 identified a deviation from Technical Specification TaskForce-425 associated with the proposed Bases. Subsequent to the submittal, the U. S. Nuclear Regulatory Commission issued additional guidance on acceptable Bases (ADAMSML109900990) which addressed the specific issue.

The insert provided in TSF-425 to replace text in the TS Bases describing the basis for each frequency relocated to the SFCP has been revised from, The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program, to read The Frequency may be based on factors such as operating experience, equipment

reliability, or plant risk, and is controlled under the Surveillance Frequency Control Program. This deviation is necessary to reflect the [DNPS/QCNPS] basis for frequencies which do not, in all cases, base frequency on operating experience, equipment reliability and plant risk.

TSTF-425, Revision 3, Relocate Surveillance Frequencies to Licensee Control -

RITSTF Initiative 5b, (ADAMS Accession Nos. ML090850627, ML090850630, ML090850638, and ML090850640) was approved by Notice of Availability published in the Federal Register on July 6, 2009. TSTF-425, Rev. 3 involves the relocation of most time-based surveillance frequencies to a licensee controlled program, called the Surveillance Frequency Control Program (SFCP), and adds the SFCP to the administrative controls section of TS. The SFCP does not include surveillance frequencies that are event driven, controlled by an existing program, or are condition-based.

Part of the TSTF-425 change to NUREG 1430 - 1434 (Standard Technical Specifications) provides an optional insert (INSERT #2) to the existing Technical Specification (TS) Bases to facilitate adoption of the TSTF while retaining the existing NUREG TS Surveillance Frequency TS Bases for licensees not choosing to adopt TSTF-425. The TSTF-425 TS Bases INSERT #2 states:

"The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program."

Several licensees requesting license amendments to adopt TSTF-425 have identified a need to deviate from this statement because it only applies to frequencies that have been changed in accordance with the Surveillance Frequency Control Program (SFCP) and does not apply to frequencies that are relocated but not changed.

The NRC staff agrees that the TSTF-425 TS Bases insert applies only to relocated SFs that are subsequently evaluated and changed in accordance with the SFCP, and that the current insert does not apply to SFs relocated to the SFCP but remain unchanged. For SFs relocated to the SFCP but not subsequently changed in accordance with the program, the existing TS Bases description remains a valid Bases for these SFs.

One option to address this concern for those instances where the licensee used TSTF-425 Insert 2, is to modify the wording used in the application as follows:

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program In addition, the following statement should be included regarding SF Bases relocated to the SFCP:

The existing Bases information describing the basis for the Surveillance Frequency will be relocated to the licensee-controlled Surveillance Frequency Control Program.

It should be noted that only the Bases for the Surveillance Frequency can be relocated to the SFCP. The Bases for the TS Surveillance will remain in the TS Bases and should not be relocated to the SFCP. The licensee is requested to provide a revision to its proposed Bases changes consistent with this guidance.

VEPCOs application dated March 30, 2010, included the aforementioned deviations from the proposed language in TSTF-425, Revision 3. The NRC staff has reviewed the proposed deviation from TSTF-425 and requests that the licensee modifies the application as described above, or develop an alternate resolution to the issue with Insert #2 as described in item 3, and including appropriate justifications.

Please submit the response to these RAIs by September 3, 2010. If you have any questions please contact me.

V. Sreenivas, PH.D., C.P.M.,

Project Manager, Rm.#O8F6, LPL2-1 North Anna Power Reactors, Units 1 and 2 Division of Operating Reactor Licensing-NRR (301) 415-2597, v.sreenivas@nrc.gov

      • This email message, and any files transmitted with it, may contain confidential, non-public, sensitive and proprietary data intended solely for the person(s) to whom this email message is directly addressed. Unauthorized use of the data contained in this message is prohibited. If you are not the intended recipient of this message or have received this message in error, please notify the sender immediately by telephone or email Reply and delete the original message and any attachments without keeping a copy***

April R. Thorpe, Contract Secretary Plant Licensing Branch 2-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Phone: 301-415-1688 Fax: 301-415-1222 April.Thorpe@nrc.gov E-mail Properties Mail Envelope Properties (AF843158D8D87443918BD3AA953ABF781625202556)

Subject:

REQUEST FOR ADDITIONAL INFORMATION: Risk Informed Technical Specifications Initiative 5b, TSTF-425 REVISION 3 Sent Date: 8/6/2010 11:44:00 AM Received Date: 8/6/2010 11:44:00 AM From: Sreenivas, V Created By: V.Sreenivas@nrc.gov Recipients:

david.heacock@dom.com ('david.heacock@dom.com')

Tracking Status: None tom.shaub@dom.com ('Tom Shaub')

Tracking Status: None

david.sommers@dom.com ('david.sommers@dom.com')

Tracking Status: None Andrew.Howe@nrc.gov (Howe, Andrew)

Tracking Status: None Gerald.Waig@nrc.gov (Waig, Gerald)

Tracking Status: None Gloria.Kulesa@nrc.gov (Kulesa, Gloria)

Tracking Status: None Post Office:

HQCLSTR02.nrc.gov Files Size Date & Time MESSAGE 0 1/1/4501 Options Expiration Date:

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