IR 05000295/1992031

Insp Rept 50-295/92-31 on 921027-930108.Violations Noted. Major Areas Inspected:Circumstances Re Apparently Closed Unit 1,1B Motor Driven Afp Discharge IV

ML20127J094
Person / Time
Site:	Zion File:ZionSolutions icon.png
Issue date:	01/15/1993
From:	Farber M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20127J075	List: IR 05000295/1992031 ML20127J073 ML20127J082
References
50-295-92-31, NUDOCS 9301250038
Download: ML20127J094 (5)

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U.S. NUCLEAR REGULATORY COMMISSION REGION 111 Report No. 50-295/92031(DRP)

Docket No. 50-295 License No. DPR-39 Licensee: Commonwealth Edison Company -

Opus West til 1400 Opus Place - Suite 300 Downers Grove, IL 60515 facility Name: Zion Nuclear Generating Station, Unit 1 inspection At: Zion, il Inspection Conducted: October 27, 1992 through January 8, 1993 Inspector: D. E. Jones Approved By: . f __

/ E Reactor Projects Section lA

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Date-i IILsDRClion_ Summary inmrtl0Lfrom October 27. 1992 throuah January 8.1H3 (Report NpMQ:

ZML91M11DBfl breas inspectedt Special, reactive safety inspection to review the circumstances regarding an apparently closed Unit 1,1B motor driven auxiliary

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feedwater (AFW) pump discharge isolation valve (ifW0038).

Basults: The f ailure to independently verify the position of IFWOO38 to be fully open during the valve realignment on October 2, 1992 is atviolation of Zion Technical Specification 6.2.1 and Administrative' Procedure (7AP)-0,

" Conduct of Operations",

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9301250038 930119 gDR ADOCK 05000295 PDR

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DElAILS Prnons_C9ntacicli

• luetken, Site Vice President, Zion Station

• 1. Joyce, Station Manager

• p tculond. Assistant Superintendent, Operations

• Wozniak, Administration

• Kaplan, Regulatory Assurance Supervisor

• Dickerson, Regulatory Assurance

• Reece-Koenig, Nuclear Licensing W. Kurth, Superintendent, production

• Indicates persons present at the exit interview on January 8,199 The inspector also contacted other licensee personnel including rnembers of the operating, maintenance, security, and engineering staf . htroole_(917921 lhis inspection was conducted to review the circumstances regarding the Unit 1,10 motor driven auxiliary feedwater -(AfW) pump dischargo isolation valve (If W0038) being found in an apparently locked closed position (not locked olen as required) following the failure to independently verify t1e position of the valvo during the October 2 realignment, a violation of Zion lechnical Specification 6.2.1 and Zion-Administrative procedure (zap)-0, " Conduct of Operations" (50-295/92031-01 (DRp)).

. OnctlpllpitqLLYRui on October 21, 1992 at 1:45 p.m., with the Unit at 97% power it was discovered that the IB AfW pump discharge isolation valve (IfW0038) was in an apparent locked closed position (not locked open as required)

while in the "unsplit" mode of operation. When IfW0038-is in:the closed position, the 10 AIW pump is isolated from the motor-driven header and cannot supply feedwater to any steam generato An equipment operator discovered the apparently closed valve while performing the valvo line-up verification check list after testing th lA turbine-driven AFW pump. The valve was fully opened within five minutes of discovery. Verification of AIW valve line-ups, and.a locked valve check list verification was performed as a compensatory measure. to ensure the operability of safety related equipmen . [han01911Y_0LlyfAh-SinirmbcLLLl992 Motor driven header split during a shutdown to repair the 1A AfW pump (IfW0038 closed)

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QI1qber 2. 1992 Motor driven header unsplit (lfW0038 apparently opened, but not independently verified open as required by Technical Specifications and administrative procedure)

DilDhcLZL_192 1:45 AfW pump discharge isolation valve (lFWOO38) found in an apparently closed position 1:50 IfWOO38 opened fully within 5 minutes of discovery ;

5. Luluation of Event i The AfW system consists of a turbine (IA) and two motor driven (IB and IC) pumps supplying turbine and motor driven headers to the steam generators. The design of the AfW system, through alignment of in-line valves (lFWOO35, IFW0037,-and ifWOO38, IFWOO42), allows for both " split" and "unsplit" modes of operation. The normal mode of operation,-during which all three AFW pumps are available, is "unsplit". In this mode valves (IFWOO35 and IFW0037) connecting the two headers are chain locked closed and- valves (IFWOO38 and IFW0042) connecting-the IB pump to the motor driven header are chain locked open. When the 1A AfW pump is

inoperable, the motor driven pumps are " split" and the IB pump supplies the turbine driven header through chain locked open valves (IfWOO35 and ,

ifWOO37) and isolated from the motor driven header by chain-locked closed valves (IfW0038 and ifWOO42).

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> The motor driven header was split on September 26, 1992 during a ( shutdown to repair the lA AfW pump. The AFW headers were returned to the l

unsplit mode on October 2,1992. Valve ifWOO38 was apparently not fully opened, and not independently verified to be fully open as required by -

Zion Administrative Procedure, ZAP-0,-" Conduct of Operations".

Upon discovery of IFW0038 in an apparently closed position on October 21, 1992, the licensee initiated an extensive root cause evaluation. Af ter interviewing approximately 74 personnel, the actual position of the valve (fully closed or-partially open) was inconclusive-.

However, factors that led the root cause team to believe that the valve

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was in a partially open position (throttled) were previous binding of .

the valve in the mid-position, and operations personnel that remember seeing the valve's rising stem above the valve handwheel. . Flow tests with the four inch gate valve partially- open (9/16") were performed and -

the valve passed the required 110 gpm flow.

i L The valve misalignment was apparently overlooked due to personnel error,-

l_ in that, valve IFWOO38 was not independently verified to be fully open j in accordance with Zion Administrative Procedure (ZAP)-0, " Conduct of Operations", during the_ valve realignment on October 2,199 . , = - . - - . - ..-.- . - = - . -

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6. Licensee Corrective Action The valve was -reopened within five minutes of discovery. The licensee verified the AFW system valve line-up and performed a locked valve check list verification on both units as a compensatory measure to ensure the operability of safety related equipmen The licensee's proposed long-term corrective actions include: annual training of equipment attendants on valve mispositioning events revision of the appropriate procedure to require running both motor driven pumps and verifying flow to each steam generator when

" splitting" and "unsplitting" headers disassembly and inspection of IFW0038 independent verification performance enforcement by the Assistant Superintendent of Operating position indication methodology for manual AFW valves will be provided by human factors engineers procedure revision to require the AFW headers to be "unsplit" during plant startup disciplinary actions for individuals involved in the event !

7. Lifety Sinnificance The licensee divided the safety analysis of the event into two cases; valve IFW0038 was either throttled open or fully close Testing concluded, in the throttled oaen (9/16") case, that the IB AFW i pump would still be able to provide t1e design basis flow of 110 gpm to '

each steam generator. Therefore, the 18 AFW pump would have been operable from October 2, 1992 to October 21,1992, in the case of IFWOO38 being fully closed, therefore rendering the IB AFW pump inoperable, 'the 1A and IC AFW pumps were operable and capable of providing 300% of design flow during the time period in questio The safety significance of this event lies in the failure of the operations department to properly control evolutions on safety-related system ,

% Conclusion-The failure to independently _ verify the position of IFW0038 to be fully-open during the valve realignment on-0ctober 2,1992 is a violation of= !

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Technical Specification 6.2.1 and Zion Administrative Procedure (ZAP)-0,

" Conduct of Operations." Exit Interview (30703)

The inspector met with licensee representatives (denoted in Paragraph 1)

throughout the inspection period and at-the conclusion of the inspection on January 8, 1993, to summarize the scope and findings of the inspection activities. The licensee acknowledged the inspector's comments. The inspector also discussed the likely informational content of the inspection report with regard to documents or processes reviewed

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by the inspector during the inspection. The licensee did not identify any such documents or processes as proprietar >

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