ML083360264

E-mail Request for Additional Information Re Exemption from Requirements of 10 CFR Part 50, Appendix R, Section III.G.1.b for Fire Area 31

ML083360264
Person / Time
Site:	Fort Calhoun
Issue date:	09/17/2008
From:	Wang A Plant Licensing Branch IV
To:	Hansher B Omaha Public Power District
Wang, A B, NRR/DORL/LPLIV, 415-1445
References
TAC MD8049
Download: ML083360264 (1)

Text

From: Alan Wang Sent: Wednesday, September 17, 2008 1:07 AM To: 'HANSHER, BILL R'

Subject:

FP RAI Bill, here is an RAI for the FP exemption. Let me know if you want a call before I issue. Alan By letter dated February 4, 2008, the Omaha Public Power District requested an exemption for the Fort Calhoun Station, Unit 1 from requirements of Section III.G.1.b of Appendix R to Part 50 of Title 10 Energy of the Code of Federal Regulations (10 CFR 50), and the 72-hour requirement to provide repair procedure(s) and material for cold shutdown capability for redundant cold shutdown components.

The proposed exemption request addresses the power and control cables for the four raw water pumps that are routed from the auxiliary building through outside cable pull boxes 128T and 129T into the underground duct bank and manhole vaults number 5 and 31 into the intake structure building.

The Nuclear Regulatory Commission staff has reviewed the information the licensee provided that supports the proposed changes to their approved fire protection program. In order for the staff to complete its evaluation, the following additional information is requested:

RAI #1 Section II of Appendix R to 10 CFR Part 50, General Requirements, states that the fire protection program shall extend the concept of defense-in-depth to fire protection in fires areas that are important to safety, with the following objectives:

- Prevent fires from starting.

- Rapidly detect, control, and extinguish those fires that do occur.

- Protect structures, systems, and components that are important to safety so that a fire that is not promptly extinguished by the fire suppression activities will not prevent the safe shutdown of the plant.

The staff requests that the licensee provide a description of the defense-in-depth features in the underground duct bank and manhole vaults number 5 and 31.

RAI #2 Your letter dated February 4, 2008 Attachment 1, Page 6, states that, In the unlikely event that all raw water pumps are lost for any reason, OPPD maintains an abnormal operating procedure (AOP) for loss of the raw water system. If all raw water pumps are lost, due to any condition, the procedure directs the operators to trip the reactor and enter emergency operating procedures (EOPs) based on observed plant conditions" AOPs often do not assume damage to collateral equipment in a fire area or cable tunnel.

Please confirm that the post-fire safe-shutdown analysis assumes that the FCS Unit 1 AOPs have all equipment available during a postulated fire.

Without a heat sink (loss of raw water), for a pressurized water reactor, EOPs often result in going to a "feed and bleed" means of protecting the core. Confirm that the post-fire safeshutdown analysis EOPs do not rely solely on feed and bleed as the means of protecting the core.

RAI #3 Clarify and confirm that the types of combustibles have not changed and total combustible loading in the intake structure building has not increased, and that there is no change in active

and passive fire protection features as last described in your letter dated August 30, 1983. If there is a change in the types of combustibles or there is an increase in combustible load or change in fire protection features in the intake structure building, the staff requests that the OPPD provide details and a basis for why the change remains acceptable.

Also confirm that the pyrocrete enclosure is in place to protect the cables for raw water pumps AC-10A and AC-10B from fire in the intake structure building.

E-mail Properties Mail Envelope Properties (419623E8C7444444BF132DA3AE69EDA2105EA954DC)

Subject:

FP RAI Sent Date: 9/17/2008 1:07:25 AM Received Date: 9/17/2008 1:07:00 AM From: Alan Wang Created By: Alan.Wang@nrc.gov Recipients:

bhansher@oppd.com ('HANSHER, BILL R')

Tracking Status: None Post Office:

HQCLSTR02.nrc.gov Files Size Date & Time MESSAGE 11242 9/17/2008 Options Expiration Date:

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