ML20196A452

Responds to Violations Noted in Insp Rept 50-155/87-22. Corrective Actions:Rev to Shutdown Procedure to Stroke Valve MO-7071 When Reactor Pressure Below 50 Psig During Plant Shutdowns Proposed

ML20196A452
Person / Time
Site:	Big Rock Point File:Consumers Energy icon.png
Issue date:	02/01/1988
From:	Frisch R CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
NUDOCS 8802050053
Download: ML20196A452 (2)

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l Consumers POW 8r L

ME AUGANIAM'S MtdNiftE55 General officos: 1945 West Parnall Road, Jack son, MI 49201 . (517) 788-0550 l February 1, M88 l

i Nuclear Regulatory Commission

! Document Control Desk l Washington, DC 20555 DOCKET 50-155 - LICENSE DPR BIG ROCK POINT PLANT -

STR0KE TESTING OF MO-7071 Inspection Report No. 50-155/87022 identified a NRC concern that while l performing T30-22 valve MO-7071 was being tested in a manner which did not i assure that maximum differential pressurr existed across the valve during l testing. During performance of T30-22, at that time, it was noted that back l

1eakage through the "telltale" between MO-7070 and VPI-303 provided evidence l that the piping between VPI-303 and MO-7071 was depressurizing (via leakage through V?I-303) and this resulted in MO-7071 being tested against maximum l differential pressure in the reverse direction. Consumers Power Company

committed to revise the test procedure as discussed with the inspectors and to submit a copy of the revised test procedure within sixty days.

A change was made to T30-22 to include the following step:

"Verify that pressure between check valve VPI-303 and MO-7071 has bled off by observing the following: With MO-7071 open observe the flow from the telltale between MO-7070 and MO-7071. Then, after closure of M0-7071, observe that the flow from the telltale decreased l indicating depressurization of the spool piece between VPI-303 and M0-7071."

The following observations were made recently while performing the revised T30-22 which requires additional action;

1. MO-7070 was opened and a steady stream was noted from the telitale.

2. M0-7070 was closed and the stream from the telltale stopped completely.

! 3. MO-7071 was opened and no flow through the telltale was noted.

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4. M0-7071 was closed with no change in flow noted, f0 OC02as-0033-n04 8802050053 800201 PDR

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o Nuclear Regulatory Commission 2' Big Rock Point Plant i Stroke Testing of MO-7071  ;

February 1,- 1988 i The abo *;e sequence indicates that check valve VPI-303 is holding and pressure is being trapped between VPI-303 and MO-7071. Under this condition the valve i may be required to function with a large differential pressure across the  ;

valve (Reactor pressure trapped between the valves and atmosphere pressure in the Reactor vessel) during an accident condition. It is believed that the i first test of M0-7071 after a start-up already shows that the valve will ,

stroke with this large differential pressure. This is due to the fact that there should be no pressure between VPI-303 and MO-7071 af ter start-up.

Since it has been discovered that the change to T30-22 previously discussed with the NRC has been found to not perform its intended purpose it is proposed to change the shutdown procedure to stroke M0-7071 when the reactor pressure  ;

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< is less than 50 psig during plant shutdowns. To demonstrate operability, this will permit stroking MO-7071 with a large differential pressure trapped between MO-7071 and VPI-303 as would be the case during an accident condition.

This change will be implenented during the next refueling shutdown currently I scheduled for April 1988.

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, {] . ' i l WhN l Ralp R Frisch i j Senior Licensing Analyst i

i CC Administrator, Region III, NRC i '

NRC Resident Inspector - Big Rock Point Plant i

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