ML18107A293

LER 99-002-00:on 990413,determined That Number 12 Auxiliary Bldg Exhaust Fan Was Rotating Backwards.Caused by mis-wiring of Motor Due to Human Error by Maint technician.Mis-wiring Was Corrected & Fan Was Returned to Svc.With 990512 Ltr

ML18107A293
Person / Time
Site:	Salem
Issue date:	05/12/1999
From:	Garchow D, Nagle J Public Service Enterprise Group
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
LER-99-002-02, LER-99-2-2, LR-N990221, NUDOCS 9905210035
Download: ML18107A293 (4)

Text

Prjbfic Ser.vice Electric and Gas Company P.O. Box 236 Hancocks Bridge, New Jersey 08038-0236 Nuclear Business Unit Regional Administrator U.S. Nuclear Regulatory Commission Region 1 475 Allendale Road King of Prussia, PA 19406-1415 Gentlemen:

IAY 181999 LR-N990221 LICENSEE EVENT REPORT 272199-002-00 SALEM GENERA TING STATION -UNIT 1 FACILITY OPERA TING LICENSE NO DPR 70 DOCKET NO. 50-272 This Licensee Event Report entitled "Auxiliary Building Ventilation Found Outside of Design" is being submitted in accordance with the requirements of 10CFR50.73 (a)(2)(ii)(B) "Any event or condition that resulted in the condition of the nuclear power plant, including its principal safety barriers, being seriously degraded;.

or that resulted in the nuclear power plant being in a condition that was outsidethe design basis of the plant". Attachment David F. Garcho General Manag -Salem Operations C U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 /JCN Distribution:

LER File 3.7 9905210035 990512 PDR ADOCK 05000272 S PDR The pu\rer is in your hands. 95*2168 REV. 6194

--1 NRC F.ORM 366 U.S. NUCLEAR REGULATORY COMMISSION

• (6-1998) LICENSEE EVENT REPORT (LER) (See reverse for required number of digits/characters for each block) APPROVED BY 011118 NO. 3150-0104 EXPIRES 06/30/2001 Estimated burden per response to comply with this mandatOI}'

information collection request 50 hm. Reported lessons learned are incorporated into the licensing process and fed back to industry.

Forward comments regarding burden estimate to the t'tacords Management Branch (T-S F33), U.S. Nuclear Regulatory Commission, Washington, DC 20555-000.1, and to the Paperwork Reduction Project (3150-0104), Office of Management and Budget. Washington, DC 20503. 11' an infonnation collection does not display a currentty valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection. . FACILITY NAME 111 DOCKET NUMBER (21 PAGE!31 SALEM GENERATING STATION UNIT 1 05000272 1 OF 3 TITLE 141 Auxiliary Ventilation Found Outsid.e of Desian EVENT DATE (S) MONTH DAY YEAR 04 13 OPERATING MODE(9) POWER LEVEL 101 NAME 99 100 LER NUMBER 161

• REPORT DATE 171 OTHER FACILITIES INVOLVED 181 I SEQUENTIAL I REVISION YEAR NUMBER NUMBER MONTH DAY YEAR FACILITY NAME DQCKET NUMBER 05000 FACILITY NAME DOCKET NUMBER 99 2 00 05 12 99 05000 TL-" --"'"' ---n. *-* *---* --1111 20.2201 (bl 20.22031a)l2llvl

50. 731all211il

50. 731all2llviii) 20.22031all1 l 20.22031a)l311il X 50. 73(a)(2l(ii)

50. 73(a)l21(x) 20.22031all2llil 20.22031all311iil

50. 731all2lliiil

73. 71

____ -+-_.0THER 20.2203(all2lliiil 50.361cll1 I 50. 731al(2)1vl Specify in Abstract below 20.22031al(211ivl 50.361cll21

50. 731all2llviil or in NRC Form 366A LICENSEE CONTACT FOR THIS LER 1121 TELEPHONE NUMBER (Include Area Codel John C. NaQle Senior Licensina Enaineer 609-339-3171 rnMDI i:Ti: nu., 1 ,.,., p--p _,, REPORTABLE CAUSE SYSTEM COMPONENT MANUFACTURER TO EPIX C:l IDlll -----*-A I 11A\ 'YES (If ves comolete EXPECTED SUBMISSION DATE). ....... ., CAUSE oo.o *LI*" DCDnDT l 1 '2\ REPORTABLE SYSTEM COMPONENT MANUFACTURER TO EPIX EXPECTED SUBMISSION DATE 1151 Mnl\lTM nAV ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) 1161 On 04/13/99 at 2135, the Unit 1 auxiliary building was identified by the operators as being at a pressure of+0.03 inches of water with respect to the outdoors.

The Updated Final Safety Report (UFSAR) Section 9.4.2.2.1 states that the auxiliary building is designed to be at a slight negative pressure continuously, with respect to the outdoors, to satisfy the criterion for preventing the uncontrolled release of radioactivity, therefore the plant was being operated outside of the design basis. Subsequent investigation determined that the #12 auxiliary building exhaust fan was rotating backwards.

Corrective maintenance activities had been performed on the prior day that required the motor leads to be disconnected.

The apparent cause is mis-wiring of the motor due to human error by the maintenance technician.

The mis-wired fan had been returned to service at 1337 on 04/13/99.

The mis-wiring was corrected and the fan was returned to service at 1110 on 04/14/99 .. Tech Spec 3.7.7.1, which provides a seven day action statement, was in effect for the duration of the event. A 4-hour report was made to the NRC as requi*red by the plant's Emergency Classification Guide and 10CFR50. 72 (b) ( 1) (ii) . This report is being made pursuant to 10CFR50. 73 (a) (2) (ii) (B) "Any event or condition that resulted in the condition of the nuclear power plant, including its principal safety barriers, being seriously degraded;.

or that resulted in the nuclear power plant being in a condition that was outsiae the design basis of the plant;" NRC FORM 366 (6-1998)

NRC FORM 366A (6-19981 U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER) TEXT CONTINUATION FACILITY NAME 111 Salem Generating Station Unit 1 DOCKE:T 121 NUMBER 121 05000272 TEXT (If more space is required, use additional copies of NRC Form 366AJ 1171 PLANT AND SYSTEM IDENTIFICATION Westinghouse

-Pressurized Water *Reactor LER NUMBER 161 I SEQUENTIAL I REVISION YEAR NUMBER NUMBER 99 02 00 Auxiliary Building Environmental Control System/Fan

{VF /FAN}** PAGE 131 2 OF 3

• Energy Industry Identification System (EIIS) codes and component function identifier codes appear as {SS/CCC} in the text. CONDITIONS PRIOR TO OCCURRENCE The unit was operating at 100% power at the time of the event. DESCRIPTION OF OCCURRENCE Operations noted, on 4713/99 at approximately 2135 hours0.0247 days <br />0.593 hours <br />0.00353 weeks <br />8.123675e-4 months <br />, that the Unit*l auxiliary building pressure was indicating

+0.03 inches of water with respect to the outdoors.

The design of the auxiliary building is for a continuous slight negative pressure with respect to the outdoors (UFSAR 9.4.). This design assures that there is no unfiltered unmonitored release of radioactivity to the environs.

Upon investigation, it was determined that the #12 auxiliary building exhaust fan was rotating backwards.

A review.of work relative to this fan revealed that the fan was removed from service at 2216 hours0.0256 days <br />0.616 hours <br />0.00366 weeks <br />8.43188e-4 months <br /> on 4/12/99 for corrective maintenance activities on a the junction box. The fan had been returned to service at 1337 hours0.0155 days <br />0.371 hours <br />0.00221 weeks <br />5.087285e-4 months <br /> on 04/13/99.

A reverse rotating centrifugal fan is able to move air but at a reduced capacity thus the total capability of the two exhaust fans was less than that of the supply fan, resulting in a slight pressurization of the building, a condition outside of the design bases. The auxiliary building is equipped with a low differential pressure (DP) alarm which did not function during this event. Investigation determined that the associated actuating device was not providing consistent actuation prior to the event and has been removed from service for repairs. During an after-the-fact review of corrective action requests by licensing, the fact that this event had been mis-classified was noted and the shift was notified to make a report to the NRC as required by the plant's Emergency Classification Guide and 10CFR50.72(b)

(1) (ii) (B), which requires reporting when the plant is found, during operation, to be in a condition that is outside of the design basis. CAUSE OF OCCURRENCE The fan had been rewired incorrectly due to human error .during restoration from corrective maintenance activities.

The independent verification associated with the activity also failed to identify the incorrect termination.

NRC FORM 366A (6-19981

. [NHC FORM 366A (6-1998) U.S. NUCLEAR REGULATORY COMMISSION FACILITY NAME (1) LICENSEE EVENT REPORT (LER) TEXT CONTINUATION DOCKET (2) NUMBER 121 SALEM GENERATING STATION UNIT 1 05000272 TEXT (If more space is required, use additional copies of NRC Form 366AJ ( 17) PRIOR SIMILAR OCCURRENCES YEAR 99 LER NUMBER (6) PAGE (3) I I REVISION NUMBER NUMBER 02 00 3 OF 3 Over the past two years several examples of improper equipment restoration have been cited in both Licensee Event Reports and Inspection Reports for Salem Units 1 and 2. (Inspection Report 98-09 and LERs 272/98-005 Inoperability Of The 12 Fuel Oil Transfer Pump Due To Installation Of Incorrect Control Switch, 311/98-002 23 Over temperature Delta Temperature Channel Found Inoperable, 311/98-004 Failure to Comply With Technical Specification Surveillance Requirement 4.1.3.1.1, and 311/98-012 22 Auxiliary Feedwater.

Pump Inoperabili ty Caused By The Failure To Restore The Pump Runout Protection Pressure Transmitter To Service Following Calibration).

SAFETY CONSEQUENCES AND IMPLICATIONS The auxiliary building ventilation system consists of two 100% supply fans and three 50% capacity exhaust fans. During normal operation one supply and two exhaust fans are in operation with exhaust flow exceeding supply flow. The exhaust fan was able to provide a significant percentage of the design flow while rotating backward, as *is typical of centrifugal fans. However, due to the reduced exhaust capacity the auxiliary building was at a slight positive pressure relative to outdoors such that there was a potential for an unmonitored leakage pathway. During the short period that the fan was operating incorrectly the radiological conditions within the auxiliary building were acceptable (no airborne contamination) thus the likelihood of an unmonitored release was very low. In addition, continuous monitoring equipment was reviewed after the event and no increase in activity was noted for the time that the building was potentially pressurized.

If there had been an accident during the period of time that the fan was rotating backwards the safety significance would have been minimal because there was an additional exhaust fan available which would have started automatically, thus ensuring negative pressurization.

CORRECTIVE ACTIONS Personnel involved with the event have been held accountable consistent with Corporate Policies.

Procedures are being modified to require the use of a phase rotation meter whenever equipment is electrically terminated.

These revisions will be completed by 06/30/99.

Although not a causal factor, the auxiliary building Low DP alarm is being repaired.

The work is currently scheduled mid July. NRC FORM 366A (6-1998)