ML040790667
| ML040790667 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 03/12/2004 |
| From: | Scherer A Southern California Edison Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML040790667 (2) | |
Text
.J ;SOUTHERN CALIFORNIA A. Edward Scherer EDISONI Manager of Nuclear Regulatory Affairs An EDISONV INTERNATIONALt Company March 12, 2004 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555
Subject:
Docket Nos. 50-361 and 50-362 Special Report- Unusual Environmental Event San Onofre Nuclear Generating Station, Units 2 and 3 Gentlemen:
In accordance with Section 4.1 of Appendix B to Facility Operating License Nos. NPF-10 and NPF-15 for San Onofre Nuclear Generating Station (SONGS) Units 2 and 3, this letter provides the required written report for an occurrence involving an unusual environmental event. On February 3, 2004, Southern California Edison (SCE) reported an unusual fish kill to the NRC (NRC Log No. 40504) and this letter provides the required 30-day follow-up written report.
On February 2 and 3 at SONGS, a routine 24-hour survey was performed to determine the amount of fish loss due to normal operations. During the sampling period, an unusually large amount of pacific sardines entered the intake. SCE determined the quantity to be approximately 13,590 pounds (roughly 6,940 pounds from Unit 2 and 6,650 pounds from Unit 3). The fish kill was likely a result of unusual environmental factors related to winter storm conditions. SCE believes the unusual fish loss was due to the simultaneous occurrence of large ocean swells, turbid water from rain runoff from nearby streams, and the presence of large schools of sardines close to shore. Under these conditions, the visual cues and guiding currents at the intake were temporarily disrupted.
Using 2002 data for reference, total fish loss for both units combined is considered to be approximately 90 pounds per 24-hour period. Historical data show between 70-85 percent of fish is returned to the ocean unharmed via the Fish Handling System.
P.O. Box 128 San Clemente, CA 92674-0128 949-368-7501 Fax 949-368-7575
- Document Control Desk At the time of the event, Units 2 and 3 were operating at about 100% power and plant operations did not change during this period. Under normal conditions, the fish elevator is operated once per 12-hour shift. However, due to the higher influx of fish, the fish elevator was operated as often as necessary to return fish to the ocean via the Fish Handling System to lessen fish loss. Since this occurrence appears to be the result of a combination of winter storm conditions and natural variation in the movement of fish schools, there are no actions that could be taken that could preclude this event or prevent its recurrence.
SCE verbally notified the San Diego Regional Water Quality Control Board of this event and no preliminary responses were received. This information will also be included in the routine Annual Marine Environmental Analysis and Interpretation Report to be issued in July 2005.
As a result of an administrative oversight, this written report is overdue. NRC Region IV Management and San Onofre NRC Resident Inspectors were notified of this oversight.
If you have any questions, please contact Mr. Geoff Cook at (949) 368-7571.
Sincerely, cc: B. S. Mallett, NRC Regional Administrator, Region IV B. M. Pham, NRC Project Manager, San Onofre Units 2, and 3 C. C. Osterholtz, NRC Senior Resident Inspector, San Onofre Units 2 and 3