ML053070552
| ML053070552 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 10/24/2005 |
| From: | O'Connor T Constellation Energy Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NMP1L 1992, TAC MC8061 | |
| Download: ML053070552 (2) | |
Text
Constellation Energy-P.O. Box 63 Lycoming, NY 13093 Nine Mile Point Nuclear Station October 24, 2005 NMP1L 1992 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001
SUBJECT:
Nine Mile Point Unit I Docket No. 50-220 Facility Operating License No. DPR-63 Clarification of Information Submitted in the License Amendment Request to Revise the Lake Water (Ultimate Heat Sink) Temperature Limit - Technical Specification 3.3.7 (TAC No. MC8061)
Gentlemen:
This letter clarifies certain information provided in a recent license amendment request that was subsequently approved by the NRC.
By letter dated August 08, 2005 (NMP1L 1971), as supplemented by the letter dated August 11, 2005 (NMP1L 1974), Nine Mile Point Nuclear Station, LLC (NMPNS) submitted an application to amend Nine Mile Point Unit I (NMP1) Technical Specification (TS) 3.3.7, "Containment Spray System." The proposed change was to increase the maximum lake water temperature limit from 81 0F to 830F. Lake Ontario serves as the ultimate heat sink for the NMP1 containment spray system and other safety-related systems. Based on its review and evaluation of the NMPNS submittals, the NRC staff concluded that the proposed amendment was acceptable.
Accordingly, by letter and enclosed Safety Evaluation (SE) dated August 12, 2005, the NRC issued License Amendment No. 190 which increased the maximum lake water temperature limit from 810F to 830F.
In the August 08, 2005 letter, NMPNS noted that the design basis analysis of the torus temperature response following a loss of coolant accident (LOCA), described in Updated Final Safety Analysis Report (UFSAR) Section XV-C.5.3, was performed using the General Electric proprietary computer code, SHEX-04. However, for the analyses performed to support the license amendment request (LAR), the letter stated only that the SHEX analysis was revised (i.e.,
the specific code version was not indicated). NMPNS wishes to clarify that the version of the computer code used to support the LAR was SHEX-05. SHEX-05 is the current code version and has been used in power uprate evaluations for several BWRs. There are no differences in the
%ciDI
Page 2 NMP1L 1992 methodology between the SHEX-04 and SHEX-05 versions. In addition to a change to the computer platform, improved input and output formats were incorporated into SHEX-05 for a better interface with code users. Benchmark calculations, which were performed before applying the SHEX-05 version for NMP 1, show that there are insignificant differences in the containment response predictions between the two versions. Therefore, NMPNS concludes that this clarification does not alter the NRC's SE conclusion regarding acceptability of increasing the maximum lake water temperature limit from 81IF to 830F.
The NRC SE for License Amendment No. 190 states that the licensee used the SHEX-04 computer program to perform analyses to support the LAR (SE Section 3. 1, pages 3 and 4). The NRC may wish to revise their SE to reference the SHEX code version actually used by NMPNS (i.e., SHEX-OS).
If you have any questions regarding this letter, please contact James A. Hutton, Director Licensing, at (315) 349-1041.
Ve ruy u
Tim hJ. O'Conn r Pla eneral Manager TJO/DEV/sac cc:
Mr. S. J. Collins, NRC Regional Administrator, Region I Mr. L. M. Cline, NRC Senior Resident Inspector Mr. T. G. Colburn, Senior Project Manager, NRR (2 copies)
Mr. John P. Spath, NYSERDA