ML030370172

E-mail from T Alexion to D Millar at ANO-1, Unit 2 Regarding Extension of Low Pressure Safety Injection (LPSI) Allowable Outage Time (AOT)

ML030370172
Person / Time
Site:	Arkansas Nuclear
Issue date:	01/23/2003
From:	Alexion T NRC/NRR/DLPM/LPD4
To:	Millar D Entergy Nuclear Operations
Billings, SA
Shared Package
ML030420086	List: ML030370171 ML030370172 ML030370238 ML030370243 ML030370253 ML030370275 ML030370298
References
Download: ML030370172 (3)

Text

g I Thomas Alexion - RAI FOR LPSI/AOT EXTENSION Paae 1 1 From: Thomas Alexion To: DMILLAR@entergy.com; SBENNE2@entergy.com Date: 1/23/03 4:24PM

Subject:

RAI FOR LPSI/AOT EXTENSION Dana, Steve, See the attached.

Tom

REQUEST FOR ADDITIONAL INFORMATION EXTENSION OF LOW PRESSURE SAFETY INJECTION ALLOWABLE OUTAGE TIME ARKANSAS NUCLEAR ONE, UNIT 2

1. What is the present annual average core damage frequency (CDF)?

2. What is the present annual average large early release frequency (LERF)?

3. What is the proposed delta LERF/year?

4. What is the proposed incremental conditional large early release probability (ICLERP)?

5. Provide the above information in addition to the delta CDF/year and the incremental conditional core damage probability (ICCDP) for external events. (See the emergency diesel generator allowable outage time application for external events.)

6. Provide additional external events information as is presently being prepared for the emergency diesel generator allowable outage time application, as follows:

a. Please describe the methodology used to generate the external events risk numbers, including the final numbers generated for each external event. If aspects of the external events analysis approach used in this application are substantially different from the methods described in previous recent applications (e.g., the power uprate application), please explain and justify the use of the different approach.

b. For the fire analyses, as an alternative to justifying the use of a different approach discussed in Question 6.a above, the licensee could describe how this application would impact each of the unscreened fire quadrant analyses and results identified in the June 28, 2001, letter to the U.S. Nuclear Regulatory Commission (NRC) regarding its power uprate application. The NRC staff notes that in this letter, the licensee identified 17 unscreened fire quadrants involving 15 fire areas and provided the associated post-uprate core damage frequency for each quadrant.

Page Pq 11I IC:\WINDOWS\TEMP\GWIOO1 .TMP Mail Envelope Properties (3E305D8F.525: 0: 20628)

Subject:

RAI FOR LPSI/AOT EXTENSION Creation Date: 1/23/03 4:24PM From: Thomas Alexion Created By: TWA@nrc.gov Recipients Action Date & Time entergy.com Transferred 01/23/03 04:24PM DMILLAR (DMILLAR@entergy.com)

SBENNE2 (SBENNE2 @entergy.com)

Post Office Delivered Route entergy.com Files Size Date & Time LPSI.AOT.RAI 4112 01/23/03 04:22PM MESSAGE 663 01/23/03 04:24PM Options Auto Delete: No Expiration Date: None Notify Recipients: Yes Priority: Standard Reply Requested: No Return Notification: None Concealed

Subject:

No Security: Standard To Be Delivered: Immediate Status Tracking: Delivered & Opened