ML20199F522

Special Rept 86-3:on 860604,svc Water Leak Discovered Inside Containment on Containment Fan Coil Unit Motor Coolers 11 & 12.Caused by Leaks on Two Plug Pipes & Head Gasket, Respectively.Pipe Plugs & Head Gasket Replaced

ML20199F522
Person / Time
Site:	Salem
Issue date:	06/18/1986
From:	Zupko J Public Service Enterprise Group
To:	NRC OFFICE OF ADMINISTRATION (ADM)
References
86-3, IEB-80-24, NUDOCS 8606240356
Download: ML20199F522 (4)

Text

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O PSEG Public Service Electric and Gas Company P.O. Box E Hancocks Bridge, New Jersey 08038 Salem Generating Stuion June 18, 1986 U. 3. Nuclear Regulatory Com.nission Document Control Desk Uashington, DC 20555

Dear Sir:

, SALEM GENERATING STATION LICENSE NO. DPR-70 DOCKET NO. 50-272 UNIT NO. 1 REPORT NO. 86-3 SPECIAL REPORT This Special Report describes the circumstances surrounding a service water leak in containment. This report is being submitted j within the fourteen (14) days specified by I.E. Bulletin No. 80-24.

J Sincerely yours, J. . Z tako, Jr.

l Ge eral llanager-Salem Operations j JLR:ama i

j C Distribution l

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8606240356 860618 j PDR ADOCK 05000272 S PDR ,

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The Energy People

% 2 t N p t M112 84

SPECIAL REPORT NUMBER 86-3 PLANT IDENTIFICATION:

Salem Generating Station - Unit 1 Public Service Electric & Gas Company Hancock's Bridge, New Jersey 08038 IDENTIFICATION OF OCCURRENCE:

Service Water Leak Inside of Containment - No.11 and No.12 Containment Fan Coil Unit (CFCU) Motor Coolers Event Date: 06/04/86 Report Date: 06/18/86 This report was initiated by Incident Report No.86-175 CONDITIONS PRIOR TO OCCURRENCE:

l Mode 1 - Rx Power 100 % - Unit Load 1135 MNe '

DESCRIPTION OF OCCURRENCE:

At 1552 hours0.018 days <br />0.431 hours <br />0.00257 weeks <br />5.90536e-4 months <br />, June 4,1986, during routine power ope. ation, a containment sump pwap run indicated an unidentified containment swap in-leakage rate of 12.5 GPM (the previous reading was less than 0.27 GPM). Technical Specification Action Statement 3.4.6.2.b was entered at that time, and a Reactor Coolant System (RCS) water inventory balance calculation was initiated.

Technical Specification 3.4.6.2 requires that RCS leakage be limited to a) no pressure bondary leakage, b) ten (10) GPM identified leakage, and c) one (1) GPM unidentified leakage.

Action Statement 3.4.6.2.b requires:

With any RCS leakage greater than ten (10) GPM identified or greater than one (1) GPM unidentified, reduce the leakage to l within limits within four (4) hours or be in cold shutdown within the following thirty (30) hours. Any pressure boundary leakage requires being in hot standby wii.hin six (6) hours and in cold shutdown within the following thirty (30) hours.

There were no evolutions in progress at the time; however, just prior to the occurrence, a tagout had been initiated on the Service Water System so that maintenance could be performed on a valve associated  !

with a service water strainer. No abnormal indications were observed in the control room; i.e., pressurizer level was stable, and there was no increase in charging flow or RCS makeup. A containment entry was perf ormed and service water leaks were discovered on No.11 and No.12 CFCU motor coolers. At 1714 hours0.0198 days <br />0.476 hours <br />0.00283 weeks <br />6.52177e-4 months <br />, af ter isolating service water to both CFCU's, containment sump pump runs ceased. At 1718 hours0.0199 days <br />0.477 hours <br />0.00284 weeks <br />6.53699e-4 months <br />, RCS unidentified leakage was oetermined to be less than 1.0 GPM and Action Statement 3.4.6.2.b was terminated.

SPECIAL REPORT 86-3 DESCRIPTION OF OCCDDDRNCE: (cont'd)

In accordance with the requirements of I.E. Bulletin No. 80-24, the Commission was notified of the event at 1655 hours0.0192 days <br />0.46 hours <br />0.00274 weeks <br />6.297275e-4 months <br />; notification was in accordance with the requirements of the Code of Federal Regulations, 10CFR 50.72. At 1921 hours0.0222 days <br />0.534 hours <br />0.00318 weeks <br />7.309405e-4 months <br />, the RCS water inventory balance calculation was completed, at which time, RCS unidentified leak rate was confirmed to be less than one (1) GPM.

APPARENT CAUSE OF OCCURRENCE:

Investigation revealed that the motor cooler for No.11 CFCU had developed a leak on two pipe plugs (which were found to be corroded),

and No.12 CFCU had developed a head gasket leak. The leaks occurred during the isolation of No.1 Service Water Bay for planned maintenance on 13SW25 (Service Water Strainer Blowdown Isolation Valve). The control room console operator perf orming the evolution closed llSW17 (Service Water Pump Discharge Cross-over Valve) prior to opening 11 and 12SW23 (Nuclear Service Water Header Cross-over Valves). This resulted in the inadvertent isolation of No.11 Nuclear Service Water Header. Realizing his mistake, the operator opened 11 and 12SW23 to restore service water to the header; however, the CFCU motor cooler leaks resulted from a pressure surge which occurred when the beader was repressurized. Although there were no procedural violations, proper judgement was not exercised when performing the ev olution. The event was therefore attributed to operator error.

ANALYSIS OF OCCURRENCE:

The RCS leakage limits are based on ensuring the ability to detect leakage from the reactor coolant boundary. The one (1) GPM value is sufficiently low to ensure early detection of additional leakage; the ten (10) GPM identified leakage limitation provides allowance f or a limited amount of leakage from known sources whose presence will not interfere with the detection of unidentified leakage by the leak l detection systems; and, pressure boundary leakage of any magnitude is  !

una cceptable, since it may be indicative of an impending gross f ailure :

of the pressure boundary. The leaks were identified, determined not l to be f rom the pressure boundary and unidentified leakage was reduced to less than one (1) GPM within the time specified by the action r eq uir ement s. Service water to the motor coolers was expeditiously isolated and the sump pumps readily removed all leakage, resulting in no accumulation of water inside of containment. With respect to the inoperable f an coil units, the CFCU's provide one-hundred percent (100%) redundancy to the Containment Spray System for the purpose of l containment cooling and depressurization during a high energy line l break inside containment. The Containment Spray System remained operational, and the loss of the CFCU's did not impact the ability to reduce or control containment pressure under accident conditions.

Additionally, both CFCU's were restored to an operable status within the time required by the Technical Specifications. This event therefore involved no undue risk to the health or safety of the public, and no equipment damage resulted from the service water leak.

However, all service water leaks inside containment are reportable in accordance with I.E. Bulletin No. 80-24.

SPECIAL REPORT 86-3 CORRECTIVE ACTION:

The CFCU motor coolers suffered no damage other than the leaking pipe plugs on No. 11 and the head gasket on No. 12. The pipe plugs on No.

11 motor cooler and the head gasket on No.,12 motor cooler were replaced. The pipe plugs on No.12 motor cooler were also replaced as a precautionary measure. The CFCU's were satisf actorily tested; No.

11 CFCU was restored to an operable status at 0215 hours0.00249 days <br />0.0597 hours <br />3.554894e-4 weeks <br />8.18075e-5 months <br />, June 5, 1986, and No. 12 was restored to an operable status at 2152 hours0.0249 days <br />0.598 hours <br />0.00356 weeks <br />8.18836e-4 months <br />, June 6, 19 86.

The operator involved was counselled concerning his actions, and other operators were apprised of the occurrence via the Operations Department Newsletter. As with all personnel error related events, the Nuclear Training Department will review this occurrence and upgrade existing training programs as deemed necessary to prevent recurrence.

Gene al M ager- I S1 Operations JLR:tns SORC Mtg 86-045

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