ML20024G714

Responds to NRC Re Items of Noncompliance Noted in Insp of License DPR-22.Corrective Actions:Relocation of Trip Test Potentiometers

ML20024G714
Person / Time
Site:	Monticello
Issue date:	06/02/1972
From:	Wachter L NORTHERN STATES POWER CO.
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML20024G713	List: ML20024G712 ML20024G714
References
NUDOCS 9104250443
Download: ML20024G714 (2)

Text

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NORYHERN STATES POWER COMPANY i

M WN E A POU S, W N N E GOTA 99409 4

June 2, 1972 I

Mr Boyce H Grier, Regional Director Directorate of Regu.tatory Operations, Region III 799 Roosevelt Road G1en Ellyn, Illinois 60137 D:ar Mr Order:

MONTICELLO NUCLEAR GENERATING PIANT Docket No. 50-263 License No. DPR-22 In your letter of May 9,1972, you identified an activity which appeared to be in noncompliance with AEC requirements. A copy of the correspondence describing this activity is attached for reference. As requested, the follow-ing information is hereby submitted.

Each of the four Main Steam Line Radiation Monitor channels is provided with a front panel Trip Test switch and an interna 14 located trip test potentio-meter. The trip test potentiometer is uced in conjunction with the Trip Test switch to supply a simulated detector input signal to the monitor for the purpose of checking the monitor trip settings. The monitor trip sottings are checked weekly.

Located within each channel in the immediate vicinity of the trip test potentiometer are the zero, upscale trip, and downscale trip adjustments.

t On April 20, 1972, a Work Request Authorization was submitted for Main Steam Line Monitors B, C, and D because the zero readings were found to be outside of the surveillance test procedure limits.

It was considered possible that an operator had inadvertentIy adjusted or affected monitor "tero" adjust-ments during the April 18th test of the trip settings. As had been previously discussed with the Assistant Plant Superintendent and Plant Results Engineer, the Engineer, Instruments decided that it was a convenient time to relocate the trip test p'atentiome'ters to the front panel of the instruments to eliminate the potential for upsetting the zero adjustments during weekly trip settin6 tests.

Relocation of the trip test potentiometers consisted of drilling a hole in the chassis front panel and chan6 ng the potentiometer mounting orientation from i

chassis floor to chassis front panel. No wires were lifted to chan6e the mount-ing orientation because there was no significant change in location. This chan6e in mountin6 orientation provided fmnt panel access to the trip test potentio-meter, and climinated the need for the operator to partially withdrav the i

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. June 2,1972 Mr Ibyce H Grier monitor chacnic drawer to perform the weekly tcut of trip settings.

The change did not involve the circuit which la active during normal operation of the monitor channel, and involved no change in the test circuit design function.

We believe there was adequate control over thic activity to the extent conciatent with its importance to safety.

This action did not constitute a change to the facility ac described in the FfdJ1 and no governed by regulations 50 59 Contrary to the implicaticn in your letter dated May 9,1972 ve believe this action does l

not and should not constitute a " change or modification to plant systems or equipment" vhich requireo the Operations Coenittee to " review and submit recom-mendations te, SAC for concurrence" (and the SAC to review and advice the Vice Precident to trike appropriate action).

It tny be noted that the developing program of additional administrative controls at Monticello vill address it.celf to changes to equipment or instrumentation which

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L Thece controls will ectablish that when the work are a part of a safety system.

to be perforced does not constitute a change as regulated by 50 59 (b), no review beyond the Cierationn Cocnittee vill be required unleco the Operations Cotnittec or the Plant FWnager specifically requests Safety Audit Committee review.

j Yourc very truly, h

L J Wachter, Vice President Powcr Prodae Lion & System Operation i

IJW/CEL/t.a i

cc: W W Lnrkin L 0bbyer 7

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