05000295/LER-1997-001-03, :on 970110,recirculation Sump Covers Were Not Installed at Original Construction.Cause Is Unknown & Impact on Plant Operation Is Unknown.Sump Cover Was Removed,Holes Were Drilled & Cover Replaced Prior to Expiration of LCO

:on 970110,recirculation Sump Covers Were Not Installed at Original Construction.Cause Is Unknown & Impact on Plant Operation Is Unknown.Sump Cover Was Removed,Holes Were Drilled & Cover Replaced Prior to Expiration of LCO

ML20134L382
Person / Time
Site:	Zion File:ZionSolutions icon.png
Issue date:	02/10/1997
From:	Brennan N COMMONWEALTH EDISON CO.
To:
Shared Package
ML20134L378	List: 05000295/LER-1997-001, Forwards LER 97-001-00 Which Involved Discovery of Lack of Sump Cover Plate Holes Contrary to Plant Structural Drawing Details,Per 10CFR50.73(a)(2)(ii)(B) 05000295/LER-1997-001-03, :on 970110,recirculation Sump Covers Were Not Installed at Original Construction.Cause Is Unknown & Impact on Plant Operation Is Unknown.Sump Cover Was Removed,Holes Were Drilled & Cover Replaced Prior to Expiration of LCO
References
LER-97-001-03, LER-97-1-3, NUDOCS 9702190082
Download: ML20134L382 (1)

LER-1997-001, on 970110,recirculation Sump Covers Were Not Installed at Original Construction.Cause Is Unknown & Impact on Plant Operation Is Unknown.Sump Cover Was Removed,Holes Were Drilled & Cover Replaced Prior to Expiration of LCO

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(iv), System Actuation 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2) 10 CFR 50.73(a)(2)(1) 10 CFR 50.73(a)(2)(ii) 10 CFR 50.73(a)(2)(x)
2951997001R03 - NRC Website

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LICENSEE EVENT REPORT (LER)

FACILITY NAME 20CKET NUMBER PAGE Zion Nuclear' Power Station Unit 1 0l5l0l0l0l2l9l5 1 l0Fl 0 l 1 TITLE Recirculation Sump covers holes were not installed at original construction; the cause is unknown and the impact on plant operation is j

Deing determined.

EVENT DATE LER NUMBER REPORT DATE OTHER FACILITIES INVOLVED l

MONTH DAY YEAR YEAR SEO.

REV.

MONTH DAY YEAR FACILITY NAMES DOCKET NUMBER (5)

I IlON UNIT 2 0l5l0l0l0l3l0l4 nli iln 9 17 917 oIo ol2 ilo al7 I I I I I I i 01011 1

THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR 5: (CHECK ONE OR MORE OF THE FOLLOWING)

OPERATING MODE 20.402(b) 20.405(e) 50.73(a)(2)(iv) 73.71(b)

)

POWER 20.405(a)(1)(1) 50.36(c)(1) 50.73(a)(2)(v) 73.71(c) 1l0l0 LEVEL 20.405(a)(1)(ii) 50.36(c)(2) 50.73(a)(2)(v11)

OTHER (Specify in 20.405(a)(1)(111) 50.73(a)(2)(1) 50.73(a)(2)(v111)(A)

Abstract below 20.405(a)(1)(iv)

X 50.73(a)(2)(ii) 50.73(a)(2)(v111)(B) 20.405(a)(1)(v) 50.73(a)(2)(111) 50.73(a)(2)(x) l l

LICENSEE CONTACT FOR THIS LER l

NAME TilFPHONE NUMPER N. M. Brennan, Regulatory Assurance ext. 2380 1

elal7 71alel-lzinlela COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT

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CAUSE

SYSTEM COMPONENT MANUFACTURER

CAUSE

SYSTEM COMPONENT MANUFACTURER j

TO NPRDS TO NPRDS B

N l l l l l l

l l g l g l l

l l l l 1 1 I I

I I I I I I SUPPLEMENTAL REPORT EXPECTED EXPECTED MONTH DAY YEAR SUBMISSION 1

YES (if yes. enmolete FXPECTED SUBMISSION DATE) l NO DATE Ol4 1l1 9l7 l

ABSTRACT (Limit to 1400 spaces, i.e.

approximately fifteen single-space typewritten lines).

On January 10. 1997, a dimee ional verification of the Unit 2 containment recirculation sump was performed in preparation for a pending l

modification. During this activity it was noted the two 1" holes were not in the sump cover plate as detailed on structural drawing B-278.

l The assumed purpose of the cover plate holes is to allow air to escape from the sump as it fills with water from the containment floor. If the sump does not vent, there is the potential to hinder or preclude flow to both Residual Heat Removal (RHR) pump suctions during the recirculation phase of a Loss of Coolant Accident (LOCA).

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Unit I was ramped down to 403 power to allow for inspection of the sump cover plate. At approximately 7:00 am on January 11. 1997 the inspection of the Unit 1 sump cover plate verified the holes were missing. Because adequate venting capability of the sump could not be proven.the operating department declared both RHR Pumps inoperable, entered Technical Specification 3.8.3. and placed the Unit 1 in a 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> limiting condition for operi. tion (LCO). The sump cover was removed, holes were drilled and the cover replaced prior to the expiration of the LCO. Upon completion of this work. the RHR Pumps were declared operable. Holes have been installed on the Unit 2 sump cover plates as well meeting the requirements of the design drawings.

The holes are believed to have been omitted because of a plant construction installation error. Investigation into the event is ongoing, and

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an evaluation is being performed to determine the safety impact of the lack of sump cover holes. Once completed. a supplemental LER will be submitted.

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9702190082 970210 PDR ADOCK 05000295 PDR S