GNRO-2003/00057, Report of Changes and Errors to 10CFR50.46 Evaluation Model
| ML032930350 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 10/20/2003 |
| From: | Bottemiller C Entergy Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| GNRO-2003/00057 | |
| Download: ML032930350 (3) | |
Text
Waterloo Road P.O. BOX 756 Port Gibson, MS 391 50 Tel 601 437 6299 Manager Plant Licensing October 2 0, 2003 US. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555
Subject:
Report of Changes and Errors to 10CFR50.46 Evaluation Model Grand Gulf Nuclear Station Docket No. 50-416 License No. NPF-29 G N RO-2003/0005?
Ladies & Gentlemen:
In accordance with 1 OCFR50.46 (a)(3)(ii), Grand Gulf Nuclear Station (GGNS) is required to report to the Commission, at least annually, the estimated effect on the limiting Emergency Core Cooling System (ECCS) analyses caused by changes to or errors discovered in acceptable ECCS evaluations. The purpose of this letter is to report two errors associated with the GGNS ECCS analyses that have been identified since the last 10CFR50.46 report dated October 31, 2002 (GNRO 2002100093). The impacted analyses were performed by General Electric Nuclear Energy (GENE) using their NRC approved SAFERlGESTR methodology.
The first error resulted in an incorrect volume split in the nodes above and below the Reactor Pressure Vessel (RPV) water surface and incorrect initial liquid mass.
The total volume of the vessel was correct. GENE determined that this error resulted in an increase of 5 O F to the GGNS licensing basis peak clad temperature (PCT).
The second error resulted in a higher initial steam separator pressure drop and overly restricted the flow through the separator during the LOCA event. GENE determined that there was no impact to the GGNS licensing basis PCT as a result of this error.
O c t o b e r 20, 2003 Page 2 of 2 G N RO-2003/00057 Therefore, the overall impact to the GGNS licensing basis PCT as a result of the errors and change listed above is an increase of 5 OF. As such, the GGNS licensing basis PCT changes from ~1845°F to <1850"F, which remains well below the 2200°F acceptance criterion of 1 OCFR50.46.
This letter does not contain any commitments. Should you have any questions or require additional information, please contact this office.
Yours truly, CAB/GW I/gwi
Attachment:
LICENSEE-IDENTIFIED COMMITMENTS cc:
Hoeg T. L.
(GGNS Senior Resident)
(w/a)
Levanway D. E.
(Wise Carter)
(w/a>
Reynolds N. S.
(w/a>
Smith L. J.
(Wise Carter)
(w/a>
Thomas H. L.
(w/o)
U.S. Nuclear Regulatory Commission ATTN: Mr. Bruce Mallett (w/2) 61 1 Ryan Plaza Drive, Suite 400 Arlington, TX 7601 1-4005 U.S. Nuclear Regulatory Commission ATTN: Mr. Bhalchandra Vaidya NRRIDLPM ATTN: FOR ADDRESSEE ONLY ATTN: U.S. Postal Delivery Address Only Mail Stop OWFN17D-1 Washington, D.C. 20555-0001 W2)
LICENSEE-IDENTIFIED COMMITMENTS TYPE ONE-CONTINUING COMMITMENT TIME COMPLIANCE (Check only one type)
ACTION None NIA NIA SCHEDULED COMPLETION DATE (If Required)