ML20211J075
| ML20211J075 | |
| Person / Time | |
|---|---|
| Site: | Catawba  |
| Issue date: | 06/10/1986 |
| From: | Tucker H DUKE POWER CO. |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NUDOCS 8611100273 | |
| Download: ML20211J075 (2) | |
Text
o DuxnPownaCor.muy P.O. nox 33180 CHAltLOTTE, N.C. 28242 HALH. TUCKER
,o Bd terreinoxe 1]
na* s (704) a73-4stu l
l June 10, 1986 l
Dr. J. Nelson Grace, Regional Administrator U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 Re:
Catawba Nuclear Sta ion, Unit 1 l
Docke.t No.f50-413, Relief From Technical Specifications
Dear Dr. Grace:
This letter constitutes written followup of a request for temporary waiver of Technical Specification requirements which was made (and subsequently granted) via a telecon between Duke Power Company personnel and members of your staff on June 5, 1986. This temporary emergency relief from compliance with Technical Specification Limiting Conditins for Operation was requested to avoid unnecessarily shutting down Catawba Unit 1.
The proposed relief request was needed to allow the unit to remain in HOT l
STANDBY to identify UNIDENTIFIED LEAKAGE from the Reactor Coolant (NC) System.
At 9:48 A.M. on June 5, 1986, it was discovered that the computer program for calculating UNIDENTIFIED LEAKAGE was showing 1.9 gpm UNIDENTIFIED LEAKAGE. At this time, the source of the leakage was not known. Allowing the unit to l
remain in HOT STANDBY for the extended period of time helped us find the leak cince the unit remained near normal operating temperatures and pressures.
If UNIDENTIFIED LEAKAGE had not been reduced to less than 1 gpm before then we would have complied with the remainder of the ACTION statement. This would i
have required the unit to be in COLD SHUTDOWN at 1:48 A.M., June 10, 1986. The i
leak was identified and the unit exited the ACTION statement at 1550 hours0.0179 days <br />0.431 hours <br />0.00256 weeks <br />5.89775e-4 months <br /> on June 8, 1986.
UNIDENTIFIED LEAKAGE of 1.9 gpm poses no challenge to the ability of the NC System to maintain system water inventory. Activity levels have remained within acceptable limits and do not indicate any gross leakage of Reactor l
Coolant. On June 1, 1986 a leak was detected allowing minor leakage of Reactor Coolant into the Component Cooling System (KC). Thisleakagehasnowbeeg c.ssegtially eliminated and activity levels in KC have dropped from 6 x 10 to 5 x 10 cpm. This is not causing any problems in the leakage calculations, l
since there are no other indications of leakage, such as rising sump levels l
inside containment or indications of primary to secondary leakage and the j
leakage barely exceeds the specification limits. The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> extension was o m oo m gtge b
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i Dr. J. Nalton C5, R2gionsl Ad=inistretor
'h June 10, 1986 Page Two justified to allow verification of the UNIDENTIFIED LEAKAGE. This extension posed no undue risk to the health and safety of the public.
This avoided one thermal cycle on the reactor and associated systems. This has real benefits in terms of availability, component lifetime and safety.
Very truly yours, get Hal B. Tucker RWO: sib xc:
Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C.
20555 NRC Resident Inspector Catawba Nuclear Station i
i l
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