05000443/LER-2004-001, For Accident Monitoring Instruments Inoperable Due to Inadequate Indicating Range
| ML042380304 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 08/17/2004 |
| From: | Kiley M Florida Power & Light Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| SBK-L-04021 LER 04-001-00 | |
| Download: ML042380304 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 4432004001R00 - NRC Website | |
text
FPL Energy Seabrook Station FPL Energy Seabrook Station P.O. Box 300 Scabrook, NIl 03874 (603) 773-7000 August 17, 2004 Docket No. 50-443 SBK-L-04021 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Seabrook Station Licensee Event Report (LER) 2004-001-00 for Accident Monitoring Instruments Inoperable Due to Inadequate Indicating Range Enclosed is Licensee Event Report (LER) 2004-001-00.
This LER reports an event that occurred at Seabrook Station on June 22, 2004. This event is being reported pursuant to the requirements of 10 CFR 50.73(a)(2)(i)(B).
Should you require further information regarding Regulatory Programs Manager (603) 773-7194.
this matter, please contact Mr. James M. Peschel, Very truly yours, FPL ENERGY SEABROOK, LLC
\\f~b 661nA, Operations Manager cc:
S. J. Collins, NRC Region I Administrator S. P. Wall, NRC Project Manager, Project Directorate I-2 G. T. Dentel, NRC Senior Resident Inspector I- If -
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ENCLOSURE TO SBK-L-04021
Abstract
On June 22, 2004, the accident monitoring instrumentation (AMI) for containment enclosure negative pressure was declared inoperable after discovery that the instruments did not encompass the range of pressure needed to measure the variable under worst case conditions.
An engineering evaluation, performed in 1991 in response to NRC Information Notice 88-76, determined that a negative pressure of (-) 0.685 inch water gauge needed to be measured at the location of the instruments to ensure that (-) 0.25 inch water gauge existed between the entire containment enclosure and the outside environment.
However, the installed instruments had a range of only 0 to (-) 0.50 inch water gauge. While Technical Specification 3.3.3.6 has a 48-hour allowed outage time for two inoperable containment enclosure pressure channels, this condition existed since 1991until discovery on June 22,2004, resulting in a condition prohibited by the Technical Specifications. A review of previous LERs identified no similar occurrences.
The cause of this event was the lack of a formal inter-discipline review of the engineering evaluation performed in 1991, resulting in a failure to recognize the AMI aspects of this instrumentation. Implementation of a design change to re-scale the containment enclosure negative pressure instruments corrected this condition. No adverse safety consequences resulted from this event.
NRC FORM 366 (7-2001)
(if more space is required, use additional copies of (If more space is required, use additional copies of NRC Forn 366A) (17)
This event resulted in no adverse safety consequences. The design function of these accident monitoring instruments is to provide information to indicate whether the containment enclosure emergency air clean up system (CEEACS) is accomplishing its design function of maintaining a negative pressure in the containment enclosure following an accident. However, the event does have regulatory significance in that it constituted a condition prohibited by the Technical Specifications.
Although the instruments were inoperable because they did not encompass the range of pressure necessary to measure containment enclosure pressure under worst case conditions, the inoperable instruments had no impact on the ability of the CEEACS to accomplish its safety function. Following the issuance of engineering evaluation SBC-475, the new pressure value was properly incorporated into surveillance procedure EX1808.014, 'Containment Enclosure Emergency Exhaust Filter System 18 Month Surveillance", which verifies the ability of the CEEACS to establish a negative pressure in the containment enclosure. The procedure uses calibrated measuring and test equipment installed at various locations in the containment enclosure, and the results have shown that the CEEACS has been capable of producing the required negative pressure.
This event was classified as a maintenance rule functional failure, as defined in maintenance rule system function PAM-01, for EAH-PDI-5782 and EAH-PDI-5789.
IV Corrective Actions Design change 04 DCR 008, Re-scaling of Containment Enclosure Negative Pressure (EAH-P-5782 and EAH-P-5789) was implemented to expand the range of the instruments to include the maximum pressure required by SBC-475.
No additional corrective actions were required to address the lack of a formal inter-discipline process in 1991 that led to this event. Since that time, the station has implemented a robust condition reporting system that provides an effective means for tracking document reviews and completing the associated actions.
V. Similar Events
None