05000245/LER-1981-018, Forwards LER 81-018/03L-0.Detailed Event Rept Encl

Forwards LER 81-018/03L-0.Detailed Event Rept Encl

ML20030B154
Person / Time
Site:	Millstone
Issue date:	07/27/1981
From:	Mroczka E NORTHEAST NUCLEAR ENERGY CO.
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20030B155	List: 05000245/LER-1981-018, Forwards LER 81-018/03L-0.Detailed Event Rept Encl 05000245/LER-1981-018-03, /03L-0:on 810629,diesel Generator Heat Detector Found Inoperable.Caused by Hanging & Bent Conduit for Capillary Tubes Due to IE Bulletin 80-11 Block Wall Mods. Watch Patrol Established & Tubes Repaired or Replaced
References
MP-1-1827, NUDOCS 8108060166
Download: ML20030B154 (2)

LER-1981-018, Forwards LER 81-018/03L-0.Detailed Event Rept Encl

Event date:
Report date:
2451981018R00 - NRC Website

text

L@

'.=

NOR'lill!AST irl'IIJI'II!S j :*l.;.1;.':. J r'"f f.%"'"

ffnffo*nE CONNECTICUT 06101 3

l:% l, X: r """

g0:n ese-6911 L

L J ;rt:1. R J T..?,l '

July 27, 1981 MP-1-1827 Mr. Boyce H. Grier A

/

Director, Region I 67 7{f y

7J/ g!

l 1}

B Office of Inspection and Enforcement fE_"/ /.LfG 6 51981 U. S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, Pennsylvania 19406 t. --

f'>,,,, _mm,<

a is

Reference:

Facility Operating License No. DPR-21 Docket No. 50-245 Reportable Occurrence R0-81-18/3L O

Dear Mr. Grier:

This letter forwards the Licensee Event Report for Reportable Occurrence R0-81-18/3L required to be submitted within thirty days pursuant to the requirements of the Millstone Unit 1 Technical Specifications, Section 6.9.1.9.b.

An additional three copies of the report are enclosed.

Yours truly, NORTHEAST NUCLEAR ENERGY COMPANY M

d'

. J. Mroczka Station Superintendent Millstone Nuclear Power Station EJM/TST:bjo

Attachment:

LER R0-81-18/3L cc:

Director, Office of Inspection and Enforcement, Washington, D. C.

(30)

Director, Office of Management Information and Program Control, Washington, D. C.

(3)

U. S. Nuclear Regulatory Commission, c/o Document Management Branch, Washington, D. C.

20555 Ye 8108060166 B10727 If PDR ADOCu 05000245 S

PDR

o s

ATTACHMENT TO LER 81-18/3L NORTHEAST NUCLEAR ENERGY COMPANY MILLSTONE NUCLEAR DOWER STATION - UNIT 1 PROVISIONAL LICENSE NUMBER DPR-21 DOCKET NUMBER 50-245 IDENTIFICATION OF OCCURRENCE onditions leading to operation in a degraded mode permitted by a limiting condition for operation.

CONDITIONS PRIOR TO OCCURRENCE The plant was operating at a steady state power level of 100 percent.

DESCRIPTION OF OCCURRENCE On June 29, 1981, at 1100 hours0.0127 days <br />0.306 hours <br />0.00182 weeks <br />4.1855e-4 months <br />, while performing routine surveillance, (Diesel Day Tank Fire Detector Functional Test), the heat detector was found inoperable. Technical Specifications 3.12.E.1 requires as a minimum, the fire detection instrumentation for each fire detection zone, including diesel generator fuel oil day tank room, shall be operable whenever equipment in that fire detection zone is required to be operable.

The diesel generator is required to be operable.

APPARENT CAUSE During the outage that began October 4,1980, block wall modifications as required by IE Bulletin 80-11, and insulation were installed in the diesel generator room.

Damage from this activity included hanging and bent conduit for capillary tubes in the heat detection system, which resulted in the system being made inoperable.

ANALYSIS OF OCCURRENCE Operability of the fire detection instrumentation ensures warning capability is available for the prompt detection of fires.

This capability is required in order to detect and locate fires in their early stages.

Prompt detection of fires will reduce the potential for damage to safety-related equipment and is-an integral element in the overall facility fire protection programs.

In the event that a portion of the fire detection instrumentation is inoperable, Technical Specification 3.12.E.2.a requires within one hour to establish a watch patrol to inspect the zone with the inoperable instrument, and at least once per hour thereafter. With this requirement fulfilled, there was no reduction in the margin of safety.

CORRECTIVE ACTION

Watch patrol was established within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> of the discovery as required by Technical Specifications.

Damaged conduit and capillary were replaced or repaired within the 14 day allowable time limit as stated in Technical Specification 3.12.E.2.b.