05000282/LER-2007-003, Regarding Unanalyzed Condition Due to Breached Fire Barrier
| ML072960414 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 10/23/2007 |
| From: | Wadley M Nuclear Management Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-PI-07-071 LER 07-003-00 | |
| Download: ML072960414 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(ii) 10 CFR 50.73(a)(2)(v), Loss of Safety Function |
| 2822007003R00 - NRC Website | |
text
October 23, 2007 Prairie Island Nuclear Generating Plant Operated by Nuclear Management Company, LLC L-PI-07-071 10 CFR 50.73 U S Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Prairie Island Nuclear Generating Plant Units 1 and 2 Dockets 50-282 and 50-306 License Nos. DPR-42 and DPR-60 LER 1-07-03, Unanalyzed Condition due to Breached Fire Barrier Licensee Event Report (LER) 1-07-03 is enclosed. The LER describes a breached fire barrier that was identified. This event was previously reported in accordance with 10 CFR 50.72 on August 24,2007.
Summarv of Commitments This letter contains one new commitment and no revisions to existing commitments.
Nuclear Management Company, LLC, will supplement this LER affer the root cause evaluation of the as-found condition is complete.
Michael D. Wadley Site Vice President, Prairie Nuclear Generating Plant Nuclear Management Company, LLC Enclosure cc:
Administrator, Region Ill, USNRC Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Department of Commerce, State of Minnesota 171 7 Wakonade Drive East Welch, Minnesota 55089-9642 Telephone: 651.388.1 121
ENCLOSURE LICENSEE EVENT REPORT 1-07-03 3 Pages Follow
Estimated burden per response to comply with this mandatory collection request: 50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br />.
Reported lessons learned are incorporated into the licensing process and fed back to industry. Send comments regarding burden estimate to the Records and FOlAlPrivacy LICENSEE EVENT REPORT (LER)
Service Branch (T-5 F52), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to infocollects@nrc.gov, and to the Desk Officer, Office of On August 9, 2007, Nuclear Management Company, LLC (NMC) staff documented an apparent breach between the Train A and Train B auxiliary feedwater pump rooms. The floor trench in the rooms is separated by a 12-inch thick concrete barrier. One of the penetrations in the barrier was a 4-inch pipe sleeve through which a 3-inch rubber hose has been run for several years. An evaluation of the as-found configuration determined on August 24, 2007, that the as-found configuration could have adversely affected the ability to safely shutdown in the event of a fire and NMC notified the NRC per 10 CFR 50.72(b)(3)(ii) as an unanalyzed condition. Thus, this event is being reported in accordance with 10 CFR 50.73(a)(2)(ii) as an unanalyzed The hose was removed and the fire barrier was restored (filled with fire-retardant wool and capped with U.S. NUCLEAR REGULATORY COMMISSION (1-2001)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION TEXT (If more space is required, use additional copies of NRC Form 366A) (17)
EVENT DESCRIPTION
On August 9,2007, Nuclear Management Company, LLC (NMC) staff documented an apparent breach between the Prairie Island Nuclear Generating Plant (PINGP) Train A and Train B auxiliary feedwater' pump rooms. The floor trench in the rooms is separated by a 12-inch thick concrete barrier. One of the penetrations in the barrier was a 4-inch pipe sleeve through which a 3-inch rubber hose has been run for several years. An evaluation of the as-found configuration determined on August 24, 2007, that the as-found configuration could have adversely affected the ability to safely shutdown in the event of a fire.
EVENT ANALYSIS
The as-found configuration was a breached fire barrier, such that the required degree of separation for redundant safe shutdown train was lacking, thus, this event is being reported in accordance with 10 CFR 50.73(a)(2)(ii) as an unanalyzed condition.
Impact on Safety Svstem Functional Failure Performance Indicator No actual loss of function occurred as a result of the as-found condition. Consequently, this event is not reportable per 1 OCFR 50.73(a)(2)(v).
SAFETY SIGNIFICANCE
This event did not result in a loss of function. In the event of a fire, it is possible that flammable liquids could have passed between rooms in the space between the hose and the pipe sleeve. The PINGP fire protection program requires compensatory measures be taken for missing or breached fire barriers (specifically, establish a fire patrol in the affected fire areas). A formal fire patrol had been established in the affected fire areas for other issues; of the several years the as-found configuration was in place, the only periods during which a formal fire patrol did not exist was from September 19,2005, to December 12, 2005 and from December 22, 2005, to April 7,2006 (with a brief exception during maintenance on January 18, 2006). Even though no formal fire patrol existed during the identified periods, a review of card reader logs indicates the fewest times the room was accessed on any day during this period was 15 times, which increases the likelihood any fire would have been detected prior to affecting redundant trains. Thus, this event did not affect the health and safety of the public and the safety significance of this event is considered minimal.
' Ells System Identifier: BA
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION
CAUSE
NMC is performing a root cause evaluation of this event. When the root cause evaluation is complete, NMC will submit a supplement to this LER.
PAGE (3) 3 of 3 FACILITY NAME (1)
Prairie Island Nuclear Generating Plant Unit 1
CORRECTIVE ACTION
TEXT (If more space is required, use additional copies of NRC Form 366A) (17)
The hose was removed and the fire barrier was restored (filled with fire-retardant wool and capped with threaded caps).
DOCKET NUMBER (2) 05000282 As part of the root cause evaluation for this event, NMC will identify additional corrective actions that will be included in the planned supplement to this LER.
PREVIOUS SIMILAR EVENTS
LER NUMBER (8)
Review of Licensee Event Reports for Unit 1 and Unit 2 since 2004 found no previous similar events where a fire barrier was found to have been breached without compensatory measures.
REVISION NUMBER YEAR 07 03 0
SEQUENTIAL NUMBER