ML19290D636

LER 80-001/01T-0:on 800202,during Routine Calibr of Pressure Transmitters for Motor Driven Auxiliary Feed Pumps, Transmitter Isolation Block Valves Discovered Closed.Caused by Inadvertent Closing of Isolation Valves.Snubbers Added

ML19290D636
Person / Time
Site:	Point Beach
Issue date:	02/15/1980
From:	Fay C WISCONSIN ELECTRIC POWER CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML19290D623	List: ML19290D622 ML19290D636
References
LER-80-001-01T, LER-80-1-1T, NUDOCS 8002220435
Download: ML19290D636 (3)

Text

3m.

_

. . . .. .- . --. .. .. - -

_ _ _ _ _-

, LICENSEE EVENT REPORT CONTROL SLOCl<: l 1

l l l l 6

lh (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATIONI

-

[0 ITl lW l I l p l B l H l 1 l@l 0 l 0 l- l 0 l0 l 0 0 l 0 l - 0 0 l@l4 1l1l1l1l@l57 CAT l l@

F S 9 L6CENSEE CODE 14 15 LICENSE NUM8ER 25 26 LICENSE TYPg JO 68 CON'T

"

' 2 l 8 l 074l@l750 l 2REPORT 1 l DATE 5l 8 1080 @

[

? 8 Eu'RC60l L l@l610 l 5 l 0DOCK0ETl NUM8ER 0 l 2 l 6 l 668l@l690 l 2 EVENT 1 0 DATE EVENT DESCRIPTION AND PROBA8LE CONSEQUENCES h o 2 l While performing a routine calibration of the pressure transmitters for t prTTl I the motor-driven auxiliary feed pumps on 02-02-80, the technician notedl io 1 [ l that the transmitters isolation block valves were closed. These trans- 1 prTO I mitters control the feed pump discharge valves to maintain feed pump l

[ O Is l l pressure. This reduced the number of immediately operable auxiliary i O 7 l feedwater pumps and is reportable in accordance with Technical l 0 g l Speci fication 15.6.9. 2. A.2. l 7 8 9 80 DE CODE $ SCO E COMPONENT CODE SU8 CODE SU E F

O 9 4

l H l Hl@ lA l@ W@ lIlNl S lT RlUl@ y @ W @

9 10 11 12 13 18 19 20

_ SE QUE NTI AL OCCURRENCE REPORT REVISION LER RO EVENTVEAR REPORT NO. CODE TYPE NO.

@yj,%ar a 21 8l01 22

[-_j 23 10 l Ol ll 24 26 l/l 27 l0l1l 28 29 lTl Jo

[--J 31 W

J2

^

TAKEN A ON ON PLANT 4 T HOURS S8 iTT FOR b 8. SUPPL MANUFACTURER W@ (_Z_j@ 0 l0 l 010 l lY @ l42N l@ W@ lFl1l8 0l@

l3JF l@34Gl@ 35 36 31 40 41 43 44 47 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS h i O l A technican inadvertently closed the isolation valves while calibratingi i i l associated instrumentation on 01-26-80. The isolation valves were I g l barely cracked and being used as snubbers. To orevent further events I g ] snubbers were added to the lines and the valves are to be administra- I g tively locked open.

7 8 9 80 ST S  % POWE R OTHER STATUS dis O RY DISCOVERY DESCRIPTION y [E_j@ 0 7 l 8 l@l N/A l l B l@l Technician observation l ACTIVITY CO TENT RELEASE AMOUNT OF ACTivlTY LOCATION OF RELEASE ITTil W @D OFRELEASEl Z l@l N/A l lN/A l PERSONNEL EXPOSU ES NUMBER TYPE DESCRIPTION i 7 l0l0 0 l@lZ l@l N/A *

,

l PERSONNE L INJURlES NUM8ER DESCRIPTION y0 0l0l@lN/A l r 8 9 n i2 80 W','E ITTil8 9W@lN/A

' "fS R PT O~'"^'''"@ 8002220 WD F to 80 PUSLICITY NRC USE ONLY

• t$$UED DESCRIPTION F

2 o 8 9 Whl N/A 10 l

68 69 lll llllll llI 80 E NAME OF PREPARER C. W. Fay PHONE: 414/277-2811 {

=

.

.

.-

ATTACHMENT TO LICENSEE EVENT REPORT NO. 80-001/OlT-0 Wisconsin Electric Power Company Point Beach Nuclear Plant Unit 1 Docket No. 50-266 While performing a routine calibration of the pressure transmitter for the motor-driven auxiliary feed pumps on February 2, 1980, the technician noted that the isolation block valves for the transmitters were closed. The trans-mitte rs , PT-4012 fo r p ump P 38 A an d P T- 4019 fo r p ump P 38B ,

control the feed pump discharge valves to maintain feed pump pressure. With the transmitter valves closed, the pump dis-charge valve would not have opened automatically on a pressure signal if the motor-driven auxiliary feed pumps were started.

The reduced number of immediately operable auxiliary feedwater pumps below the minimum required for two unit operation for a period greater than the permitted 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is reportable in accordance with Technical Specification 15.6.9.2.A.2.

It should be noted that flow meters on the discharge of the auxiliary feed pumps and the discharge valve position indication were operable at all times; these indications are on the main control board and would enable the operator to note the no-flow condition and closed valve position in the event of a pump start.

~ The turbine-driven auxiliary feed pumps , one per unit, were immediately available at all times. Each turbise-driven pump is capable of supplying the required 200 gallons per minute to each steam generator under loss of feedwater conditions.

An additional safety factor under this degraded con-dition was the approximately 38 minutes of feed water inventory available in each steam generator in the accident situation. This 38 minute period (conservatively presuming that only .one steam generator was available) would provide ample time for an operator to provide additional auxiliary feed water to the steam generators utilizing the motor-

'

driven pumps with a minimum amount of operator action.

The ~cause of this event appears to be the error of a technician, who on January 26, 1980, inadvertently closed the heavily snubbed transmitter isolation block valves. The technician was calibrating an associated pressure gauge and closed the isolation valve which was barely cracked open, doubling as a snubber. The technician did not realize that the valve was, in fact, an open valve.

a

.

The isolation block valves are no longer used as a sn ubbe r. Snubbers have been placed in the instrument lines to preclude the need to throttle these valver and prevent future events of this nature. The isolat iem bloc k valves have also been added to the auxiliary feedwater s (stem valve check list and will be tagged to ensure that thel:'" locked open" position is maintained.

'

There have been no similar past occurrences of this nature.

.

S O