ML17311A981

During the Unit 2 refueling outage

completed

in March 1995,

a total of 95 valves

were repacked

and

32 were safety-related

The inspector

concluded that the licensee

was aggressively

implementing

the valve repacking

program to improve the material condition of the plant

and

the performance of the valves.

The inspector

also noted that the licensee

was

placing

a high priority on repacking

the safety-related

4.3.3

Plant

Walkdown

The inspector identified three

MOVs with apparent

packing leaks in Unit 2 on

May 3 during

a routine plant tour.

The inspector

informed the valve services

group

and they conducted

a walkdown of the safety-related

MOVs in Unit 2 and

.

identified nine more valves with apparent

packing leaks.

The licensee

subsequently 'determined that eight of the

12 leaking valves

had

been

identified two weeks earlier during operations

and engineering

system

~

walkdowns.

The inspector determined that four of the leaking valves

had

been

repacked

during the Unit 2 outage

in March 1994.

The inspector

noted that

Valve CH-524 had

a significant leak and appeared

to be actively leaking.

The

other three valves

had small

amounts of boron

on the

stem but did not appear

to be actively leaking.

The inspector

reviewed the

VSDS for Valve CH-524

and noted that the valve was

properly packed

and that the packing gland

was properly tightened,

The

inspector

noted that for motor-operated

valves the mechanics

tighten the

packing gland towards the low end of the required torque range.

The valve

services

group subsequently

performs

an as-left static diagnostic test

and

ensures

that the packing load is within the proper range.

The diagnostic test

procedure

has general

guidance that the running load should

be around

1000 pounds for each

inch of stem diameter.

The procedure

also includes

guidance that the packing should

be tightened if the running load is low.

The

inspector

concluded that the licensee's

procedures

provided adequate

guidance

to ensure that the packing of MOVs was not tightened

too much, which would

prevent operation of the valve, or not tightened

enough,

which would allow the

valve to leak.

The inspector

noted that the as-left diagnostic test

was performed with the

system filled, but not at normal operating

pressure

and temperature.

As

a

result,

the packing

may have loosened

causing

the valve to leak when the

normal

system pressure

was reached.

The licensee

agreed

to evaluate

optimizing when as-left diagnostic tests

were conducted

to minimize the

potential for subsequent

packing leaks.

The inspector

concluded that the

I

'icensee's

actions

were appropriate.

0

)

j

4.4

Other Maintenance

Work Observed

The inspector

observed

portions of the work listed below:

Feedwater

isolation valve accumulator nitrogen pre-charge - Unit l.

Disassembly of turbine driven auxiliary feedwater governor valve

Unit'.

5

SURVEILLANCE OBSERVATION

(61726)

5.1

Hain Steam Isolation Valve Testin

- Unit 2

On Hay 9, the inspector

observed

a portion of main steam isolation valve

(HSIV) partial stroke testing in Unit 2.

The inspector

observed

good

command

and control of the test

by the control

room supervisor

and the reactor

operator performing the test.

For example,

the operators

had briefed

contingency actions

in the event

a MSIV went closed

and were closely

monitoring the HSIV accumulator

pressure

for any abnormal

trends during the

test.

The inspector also observed

good communications

between

the auxiliary

'perator

and the control

room operators.

t

6

EMPLOYEE CONCERNS

PROGRAM REVIEW

The inspector

performed

a review of the licensee's

Employee

Concerns

program

(ECP)

and Management

Issues

Tracking

and Resolution

program

(MITR).

The fCP

provided employees -a method for independent

review of .technical

and safety

concerns

which they did not consider

would be adequately

resolved

through

normal

processes.

The MITR provide employees

similar review for personnel

and

administrative

concerns.

The inspector

noted the following concerns:

The HITR program

was not covered

by

a formal administrative

procedure.

As

a result,

there

were

no consistent

requirements

for the content of

MITR files or how they were to be closed.

Review of Files 94-01,

94-06,

94-09,

and 94-10 identified the following concerns:

~

The files did not include appropriate

documentation of evaluation

conclusions.

~

The files did not include final closure

correspondence

to the

concerned

employee

as to how each of his concerns

had

been

resolved.

~

The files did not indicate

any cause

evaluation or corrective

action for problems that

had resulted

in val'id employee

concerns.

~

HITR 94-43 addressed

a discrimination concern involving an engineer

having raised

safety concerns

about

ADV problems

in

a report to the

NRC.

It was not clear from the file that the concern

received

an

1

-12-

appropriately

independent

evaluation,

in that the concern

was evaluated

by the Vice President

to whom the alleged discriminating manager

was

a

direct report.

The file did not clearly .indicate the basis for Human

Resources

department

conclusion that this

I'0 CFR 50.7 concern

received

a

proper

independent

evaluation.

~

The inspector identified the following concerns

in a review of ECP

administrative guidelines

ECPOI,

ECP02,

ECP03,

and

ECP Files 94-07-03,

94-08-05,

94-09-02,

94-10-03,

and 95-01-07:

ECP Administrative Guideline

ECP02

(Handling

ECP Concerns)

does

not require

an initial letter to the concerned

employee

which

clearly documents

the scope of his concerns,

the plan of action to

evaluate

the concerns,

or. the target

schedule for completing the.

evaluation,

nor does

the guideline require

a final closure letter

to the employee

which documents

the conclusions

and

actions'esulting

from the

ECP evaluation.

~

File 95-01-07 did not indicate

any cause

evaluation or corrective

action for the mishandled

CRDR investigation

problem identified

during the

ECP evaluation.

ECP Administrative Guideline

ECP03

(ECP File Open Action Tracking)

does

not address

completion of file closure followup with the

employee.

~

The cl'osure followup for File 94-10-03 indicated that the employee

considered

that the hostile work environment

in his work group

had

"drastically improved," however,

NRC interview with the concerned

employee indicated that the employee still considers that

supervisors

in his work group are hostile to employees

raising

safety concerns.

~

The inspector interviewed six employees

who recently

had discrimination

concerns

evaluated

by the

and

MITR programs.

These

employees

consistently

expressed

satisfaction with the performance of the

program;

however,

some stated that they were not confident with the

MITR

program,

indicating that the

Human Resources

department

was not viewed

as

a credible organi'zation for representing

employee's

best interests.

The employees

also stated that senior licensee

managers

had increased

their credibility in recent

months

such that employees

were confident

that they could

come to senior managers

and receive fair treatment,

without fear of retribution.

However,

several

of the

same

employees

stated that they did not have similar confidence

in lower levels of

licensee

management

and supervision.

While progress

had

been

made in the

MITR and

and employees

seemed

generally satisfied with the

ECP,

some programmatic

weaknesses

were

identified.

The inspector discussed

these

findings with licensee

senior

~

'

0

-13-

management

responsible

for the

and

MITR programs.

They concurred with the

inspector's

observations

and planned to implement appropriate corrective

actions.

7

FOLLOWUP MAINTENANCE (92902)

7. 1

Closed

LER 529 94-008

and

Closed

Unresolved

Item 529 9431-06:

Use

Of Uncalibrated

Boronometer

Caused

a

TS Action to be Missed

This

LER involved operator's

use of an uncalibrated

boronometer to verify

reactor coolant

system

boron concentration

in order to comply with the

compensatory

action requirements

of TS 3. 1.2.7 which applied in February

and

March

1994

when

a startup

channel

was

removed

from service.

7.1.1

Background

Instrumentation

and Controls

(I&C) technicians

began

a routine 18-month

calibration of the Unit 2 boronometer

in February

1993.

They found that

one

of the instrument's

power supplies did not meet the calibration

specifications.

The

ILC technicians

stopped

work, left the boronometer

in

service, notified the Shift Supervisor,

and proceeded

to attempt to procure

a

new power supply.

The boronometer

appeared

to be operating

adequately

in that

it closely tracked reactor coolant

system

boron concentration.

The

ILC group performed work on the boronometer sporadically until November

1994.

Near the time the calibration

was completed

in November

1994,

the

licensee identified that the boronometer

may have

been

used

by operators,

during the Unit 2 refueling outage in February

and March 1994, to satisfy the

compensatory

action requirements

of TS 3. 1.2.7 which apply when

a startup

channel

was

removed

from "service.

The licensee

concluded this review in

January

1995,

having found that the boronometer

was relied

on in three

occasions.

On one of the occasions, if no credit is provided for the

use of

the boronometer to meet the

TS action,

the

TS action

was not complied with.

The inspector

noted that, despite

the questionable

calibration status of the

boronometer,

during the period it was

used for TS compliance, it remained

within

1 to

2 percent of the

RCS samples.

The inspector

reviewed the

LER and found that there were significant

weaknesses

in the evaluation of the cause of the event

and the corrective

actions

taken.

Further,

the inspector

found that the licensee's

internal

evaluations

which support the

LER were weak.

7. 1.2

Evaluation of the

Cause of the Event - Operations

The

LER statement

of cause

states,

in part:

"An evaluation

was performed

in accordance

with the

APS Incident

Investigation

Program.

The evaluation

concluded that the apparent

cause

of the boronometer

past calibration

was

a lack of concern for the

instrument

being calibrated correctly."

I

e

-14-

The inspector

noted that the cause, statement

did not address

the barrier

necessary

to prevent

an operator

from using

an boronometer of questionable

calibration to satisfy

a

TS requirement.

The inspector determined,

through

discussions

with operations

personnel,

that the appropriate

administrative

control would have

been for operators

to have

made

a control

room deficiency

log

(CROL) entry with a

CRDL tag placed

on the control board.

The licensee's initial CROR (2-4-343) evaluation identified that

I&C had

informed the shift supervisor that the calibration of the boronometer

had not

been completed.

The

CROR noted that

a second

CRDR (2-4-4?1)

was initiated for

operations

to evaluate

how the boronometer

was allowed to be used while it was

being calibrated.

CROR 2-4-471 identified that the issue

was reportable

under

10 CFR 50.73,

but did not provide any root cause

review.

The inspector

found

that,

CROR 2-4-343

was closed

based

on the evaluation to be performed in

CROR 2-4-471.

However,

CRDR 2-4-471

was subsequently

closed without a

documented

evaluation of cause

and without further corrective actions

based

on

the evaluation

provided in

CRDR 2-4-343.

As

a result,

there

was

no documented

evaluation of operations failure to identify and tag the boronometer

'eficiency.

7, 1.3

Evaluation of the

Cause of the Event - Maintenance

The licensee

had

made

some effort to identify what the inspector considered

to

be

a contributing cause

concerning

the lack of a timely calibration of the

boronometer.

The licensee identified that the calibration

had not been given

priority due to the fragmentation of the responsibility for the resolution of

equipment reliabili.ty problems.

The inspector

reviewed this evaluation

and found that it lacked rigor.

The

preventive maintenance

(PH) task to calibrate the boronometer

was considered

to be

an "operations surveillance test no-waive

PH."

The

PH task,

which had

an 18-month frequency,

had last

been completed

on September

26,

1991,

and

was

due

on March 26,

1993.

The licensee

allowed

a grace period to August 23,

1993.

The boronometer

was recognized

in its

PH basis

documentation

as

providing post-accident

indication in accordance

with Regulatory

Guide 1.97:

On July 29,

1993,

an

I&C foreman performed

a

PM work order disposition report

to delay the calibration of the boronometer.

No justification was provided

and the due date

was extended

to September

26,

1993.

The work was not

completed

in September

1993

and

no further delay requests

were documented.

In September

1994,

a Shift Technical Advisor discovered that the

PM had not

been completed.

The

I&C section leader

performed

a

PH work order disposition

report to waive the original

PH task.

CRDR 2-4-343

was initiated

and the

calibration

was completed

in November

1994 under

a new work order.

The waiver

of a "no-waive"

PH was considered

an Unresolved

Item in Inspection

Report

94-31.

The evaluation

in

CRDR 2-4-343,

which was included in the

LER, discussed

the

lack of priority placed

on calibrating the boronometer.

However, it did not

f

address

the specifics of what barriers

are provided to ensure that priority is

appropriately

placed

and

how these barriers

may have

been defeated.

Specifically:

~

Regarding

the disposition

on July 29,

1993,

how could

a "no-waive"

PM be

delayed with no documented justification for the delay?

~

After the first delay expired

on September

26,

1993,

why were there

no

subsequent

"no-waive"

PM dispositions

documented?

~

Why were there

no controls in place to ensure that post-accident

monitoring instrumentation

referred to in the Updated Final Safety

Analysis Report

be returned to service

in

a expeditious

manner?

7. 1.4

Evaluation of Corrective Acti'ons

The inspector

reviewed the actions to prevent recurrence

discussed

in the

LER.

The

LER stated that the following step

had

been

added to the

PM Process

and

.

Activities procedure:

" 18C Section/Team

Leaders

shall refer out-of tolerance results

found

during Operations

Surveillance

Tests

"NO WAIVE" PMs

on installed plant

equipment to the duty

STA or other appropriate

engineering

personnel.

The STA/engineer shall

perform

a documented

evaluation of the

significance of the problem or deficiency

and ensure that

a

CRDR is

generated, if required."

The inspector

found that this step did not address

any of the problems

noted

in the

LERs or the

CRDRs associated

with the boronometer.

The inspector

interviewed

a Shift Technical Advisor (STA),

a Control

Room Supervisor,

a

Shift Supervisor,

an

I8C Team Leader,

and

an

18C Section leader

and determined

this step.was

intended to ensure that out-of-tolerance results

are

appropriately

reviewed for their impact

on tests for which they may have

been

relied

upon

and to trend

and assess reliability of the instrument.

Typically,

as-found out-of-tolerance

results

are quickly resolved

and the instrument

placed

back in service with no impact

on ongoing plant operations.

Therefore,

IKC typically refers

subsequent

out-of-tolerance

reviews to

IKC maintenance

engineers

and not the STAs.

Furthermore,

the inspector

noted that the boronometer calibration procedure

included

two steps requiring

18C to notify the control

room of out-of-

tolerance

findings

and that this was done for the subject calibrations.

The

LER concludes

by stating that the evaluation of the event

had not been

completed.

The

LER was issued

on February

7,

1995.

All open evaluations

of

the issue

were closed

by February

14,

1995, without further documented

review.

0

I

l

'I

-16-

7. 1.5

Conclusion

The failure to assure

that

an instrument

used to meet

TS requirements

was

properly calibrated is

a violation of 10

CFR Part .50,

Appendix B,

Criterion XII, concerning

the control of measuring

and test equipment

(Violation 529/9510-01).

The inspector

noted that the licensee identified

this violation in December

1994-.

However,

the inspector considered

that the

licensee

had not performed

an adequate

cause

review nor identified appropriate

corrective actions to prevent recurrence.

The inspector considered

this to be

potentially significant in this case

since it appeared

that both licensee's

corrective actions

and event report programs failed to ensure that

an adequate

review was performed.

7.2

Closed

Unresolved

Item 50-529 94-26-02:

Failure of Motor-0 crated

Valve to Close

This unresolved

item involved the failure of a Unit 2 containment

spray

(CS)

miniflow isolation Valve SIA-664 to close during

a surveillance test

.on

September

5,

1994.

The valve also failed .to close

on August

17,

1994,

when

'perators

attempted

to verify the valve was

open

by closing the valve.

The licensee

conducted

a root cause of failure analysis

and determined that

t

the failure of Valve SIA-664 to close

was caused

by an excessive

running load.

The licensee

determined that the excessive

running load was caused

by an

obsolete

packing configuration

(10 braided rings

and

a lantern ring) .that

was

originally installed in the valve.

The valve was repacked

using low

resistance

packing,. manufactured

by Argo,

and returned to service.

The

licensee

also

changed

the bill of materials to specify the Argo packing

and

initiated work requests

to repack the Unit

1

CS and low pressure

safety

injection (LPSI)

pumps miniflow valves during the Unit

1 refueling outage

in

April 1995.

The inspector initiated the unresolved

item to assess

whether the torque

switch (T(S)

was correctly set

and if the licensee's

response

to the initial

failure to close

on August

17 was appropriate.

The licensee initiated

CROR 2-4-0301 to address

the inspector's

questions.

The inspector

reviewed the licensee's

CROR evaluation,

reviewed all the

previous diagnostic traces for Valve SIA-664,

and

had

numerous

discussions

with members of the valve services

group.

In summary,

the inspector

noted the

following weaknesses

with the licensee's

overall

response

to the problems with

Valve SIA-664:

~

The licensee

did not conduct

a thorough review of the issue

in response

to the unresolved

item.

The inspector

had to prompt

a more thorough

review which eventually led to discovering that Valve SIA-664 was

inoperable

between

August

17 and September

5,

1994.

0

~,

-17-

The licensee

did not perform

a thorough, critical review of past

diagnostic traces

to assess

the future performance of the Valve SIA-664.

As

a result,

the licensee failed to identify an anomaly in the

diagnostic traces of Valve SIA-664 which wa's

a precursor to the failures

on August

17 and September

5,

1994.

The licensee

did not have

any requirements

for the technicians

analyzing

diagnostic traces

to perform

a qualitative assessment

of the quality and

shape of the traces.

The inspector pointed out to the valve services

group the potential

problems with not performing this type of

qualitative assessment

of the diagnostic traces

in Inspection

Report 50-528/94-13

and the licensee

did not provide any additional

tools or training to help the technicians

recognize trace

anomalies.

The inspector

noted that the response

by the valve services

group to this

problem was poor,

but not typical.

For example,

the licensee

identified: and

promptly corrected

anomalies

in butterfly'valve traces.

This was noted

as

a

strength

in Inspection

Report 50-528/93-32.

However,

the inspector

concluded

that the weaknesses

described

above highlighted the

need for improvement in

the use of diagnostic trace information and the thoroughness

of evaluations

in

response

to unresolved

items.

t

7.2. I

Licensee's

Response

to the Unresolved

Item

The licensee initiated

a

CROR evaluation

in response

to the unresolved

item

and concluded that the T(S was properly set

and that the operator

had

sufficient available thrust to close the valve.

The licensee

reviewed

April 1992 diagnostic test data

and noted that Valve SIA-664 had about

4800 pounds of available thrust

and

a running load of 1800 pounds.

The

September

5,

1994,

as-found diagnostic test data

showed

2000 pounds of

available thrust

and

a running load of 2500 pounds.

The licensee

had

an upper

limit on running load of 2580 pounds.

The licensee

subsequently

concluded

that the

TOS was properly set

and that the higher than normal running load

caused

the close

T(S to interrupt the travel of the valve.

The inspector

reviewed the

CRDR and

had the following observations:

~

The licensee

had not evaluated

the operability of Valve SIA-664 between

the two apparent failures to close

on August

17

and September

5,

1994.

~

The licensee

had not determined

what would have

caused

the close

TgS to

trip if there

was still 2000 lbs of available thrust to shut the valve.

The inspector

asked

the licensee

to perform

an evaluation of the operability

of Valve SIA-664 and to review previous diagnostic traces of Valve SIA-664 to

explain the apparent

close

TgS trip on August

17 and September

5.

The

licensee

subsequently

determined that Valve SIA-664 would not'ave

been

able

t

to close

between

the two failures

and was, therefore,

inoperable for about

19 days.

e

7.2.2

Operability Evaluation

-18-

e

The inspector

reviewed the design

basis function of Valve SIA-664 to determine

the safety significance of the valve being inoperable

and to determine

the

subsequent

impact

on the overall operability of the

CS system.

Valve SIA-664

is normally open to provide

a flow path to the refueling water tank

(RWT) when

the

pump is started with the discharge

isolation valves shut.

Valve SIA-664

receives

a recirculation actuation

signal

(RAS) to close during the

recirculation

phase of a loss of coolant accident

(LOCA).

As described

in the licensee's

Updated

Final Safety Analysis Report,

Valve

SIA-664 received

a close signal to prevent the transfer of radioactive fluid

to the

RWT, mitigating

a potential

release

in excess of 10 CFR Part 100

limits.

Additionally, closing SIA-664 would prevent

a loss of inventory in

the containment

sump that eventually could challenge

the operation of the.

safety injection pumps.

TS 3.6.2.

1 required that two independent

CS systems

be operable with the

capability to automatically transfer suction to the containment

sump'n

a RAS.

As described

above,

a specified function of the

RAS is to close the

CS min'imum

flow recirculation valves.

The action statement

of TS 3.6.2. 1 allowed the

licensee

to have

one train of CS inoperable for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

Train A of CS was

inoperable for 19 days,

from August

17 to September

5, l994, in violation of

TS 3 .6 .2 . I (Violation 529/9510-02)

.

The inspector

noted that operators

would receive

an alarm indicating that the

Valve SIA-664 did not move to the closed position

on

a

RAS.

Manual operation

of the valve would be prevented

due to the

assumed

high radiation levels in

the auxiliary building.

However, operators

could secure

the operating

CS

pump

and line-up the

LPSI

pump to provide containment

heat removal.

The licensee's

probability risk assessment

(PRA) group ranked the failure of

Valve SIA-664 as having low safety significance during the scoping of the

generic letter

(GL) 89-10

MOV program.

The

PRA group did not model

a failure

'of Valve SIA-664 because

they assumed

operation of a redundant

valve in the

miniflow line to the

RWT (Valve SIA-660) that also received

a signal to close

on

a

RAS.

Based

on this information, the inspector

concluded that the safety

significance of having Valve SIA-664 inoperable

was low.

The licensee

determined that Valve SIA-664 being inoperable

was reportable

and

planned to submit

an

LER.

The licensee

stated that they would perform an

evaluation of the impact

on the Part

100 dose limit calculations

due to the

known failure of Valve SIA-664 and

an

assumed

single failure of the redundant

Valve SIA-660.

e

-19-

7.2.3 Diagnostic Trace Anomalies

The licensee

reviewed the previous diagnostic traces of Valve SIA-664 in

April 1995

and determined that there

was

an anoma'ly in the springpack

displacement

curves at the beginning of the close stroke that

had not been

previously identified and evaluated.

The licensee typically measures

the deflection of the

HOV springpack during

diagnostic tests.

The deflection of the springpack is directly proportional

to the output torque of the motor operator.

The beginning of a typical spring

pack deflection curve

shows

a steady

increase until the valve stem begins to

move through the valve packing.

At this point, the springpack deflection

should stay at

a relatively constant

value corresponding

to the running load.

The magnitude of the running load is largely determined

by the dynamic

friction between

the packing

and the valve stem.

The spring pack deflection

curve stays

at the running load .value until the valve plug begins to enter the

valve seat..

At this point the spingpack displacement

rapidly'increases

until

the operator

reaches

the point where the torque switch trips

(TST)

and the

valve is fully seated.

The licensee

reviewed the springpack deflection curves for Valve SIA-664 and

noted that the springpack displacement

curves

had

a large spike at the

beginning of the valve stroke that

was significantly larger than the

displacement

corresponding

to the running load.

The licensee

called the

magnitude of the spike the breakaway

and initially thought that it was

caused

by

a combination of the higher than

normal

packing friction and the

unique rotating rising stem

(RRS) valve.

In the

RRS valve, the stem not only

moves vertically, but it also rotates

through the packing.

In most other

HOVs, the valve stem goes vertically through the packing with no rotating

motion.

The inspector

reviewed the previous diagnostic traces for Valve SIA-664 and

noted the value of the as-found

and as-left

breakaway

torque,

the running load

torque,

and the torque at TST.

The inspector

noted that the breakaway

spikes

were consistently larger than the running load

and

on several

occasions

were close to challenging

the close

TgS

and operation of the valve.

The

torque values

are recorded

as

inches of springpack displacement

and were

as

follows:

I

0

l

0

Hay 1989

As-Found

As-Left

-20-

Hay 1991

As-Found

As-. Left

September

1994

.

As-Found

As-Left

Break-away

Running

Torque

Switch Trip

0.1335"

0.1490"

0.0785"

0.0610"

0.1685"

0.1645"

0.1771"

0.1103"

0.1674"

0.0820"

0.1362"

0.0171"

0.0425"

0.0834"

0.0132"

0.1923"

0.1537"

0.1771"

7.2.4

Inadequate

Corrective Actions

The inspector

concluded that the licensee

did not evaluate

the impact of'the

breakaway

torque spikes

on operation of Valve SIA-664 in 1989,

1991,

and

1994;

Additionally, the inspector determined that the licensee

was only trending the

minimum available thrust to close the valve

and

had not recognized

the spikes

as

an anomaly that needed

to be trended.

The inspector

noted that after valve

SIA-664 was repacked

in 1994 with the Argo packing,

the breakaway

torque spike

was not present

in the subsequent

traces.

t

The inspector

concluded that the licensee

had several

opportunities to

identify and correct the high breakaway torque which challenged

the

operability of Valve SIA-664 and did not take appropriate corrective actions.

As

a result,

the valve subsequently

failed to perform on two separate

occasions.

The previous opportunities to identify and correct the condition

are outlined below:

7.2.4.

1

Initial Review of 1989

and

1991 Traces

The inspector

noted that the large

breakaway

torque existed since the i'nitial

1989 trace

and could have

been identified during the initial implementation of

the

GL 89-10 program.

For example,

the

May 1991 as-found trace

showed

the

breakaway

as high as the torque at TST,

a condition which should

have

caused

the valve not to stroke.

This fact was not identified and trended.

The inspector

concluded that the

NOV program

was still maturing at that time

and'he

licensee

apparently did not have

enough

experience

to recognize

the

torque spike

as

an anomaly.

7.2.4.2

August

1994 Failure to Close

On August

17,

a control

room operator

attempted

to close Valve SIA-664 and

an

auxiliary operator

observed

the valve stem rotate

about

I/O of a turn.

The

control

room operator

observed

both the

open

and close valve position lights

indicating the valve

had stopped

in mid-position.

Control

room operators

t

subsequently

went to close

again

and Valve SIA-664 went fully closed.

The

valve was then successfully

stroked five more times.

0

-21-

The inspector

noted that Unit 2 operators

had not informed the valve services

group of the failure of Valve SIA-664 to close

(Inspection

Report 50-528/94-31).

The inspector

subsequently

informed the valve services

group

and

asked for their

assessment

of the potential

cause of the problem."

The valve services

group

determined that

once the valve began to move only the

MOV torque or limit

switches

could have

stopped

the valve from fully closing.

The valve services

group did not perform any subsequent

testing or inspection of the valve because

they

assumed

that

any evidence of the problem was destroyed

by repeatedly

stroking the valve.

The inspector

concluded that

as

a minimum the licensee

should

have evaluated

the

past diagnostic traces of Valve SIA-664 after the August

17 apparent failure to

close.

Had they reviewed the traces,

they could have identified the abnormally

high running loads

and possibly the breakaway

anomaly.

The inspector

also noted that the licensee

had problems with unexplained

losses

in the available closing torque with similar

RRS valves in Units

2 and 3.

In

some of these

cases,

there

was unusually high running loads

caused

by friction

between'the

valve plug and the valve seat.

The inspector

concluded that the "

licensee

should

have performed

a diagnostic test after the August

17 problem

based

on the

known unpredictable

performance of RRS valves.

The inspector

b'ased

this conclusion

on the fact that the only real indicator of future performance of

an

MOV is

a diagnostic test

and the extent of controls

on the use of diagnostic

equipment

should

be commensurate

with the degree of uncertainty

in the

performance of the valve.

The inspector further noted that the licensee

had

a procedure for troubleshooting

MOV failures in August

1994.

The stated

intent of the procedure

was to "provide

a guideline for use in troubleshooting

MOV actuator failures,

and to ensure that

the cause of the failure determined,

corrected,

and documented".

The inspector

reviewed the procedure

and noted that there

was

a section for troubleshooting

a

TST which would have eventually led the technicians

to perform

a diagnostic test.

7.2.4.3

September

1994 Failure to Close

The inspector

noted that the licensee

had another opportunity to identify and

evaluate

the breakaway

torque spikes after the September

1994 failure to close

and subsequent

root cause of failure analysis.

The inspector

noted that

a review

of the as-found trace

on September

5 clearly shows the break

away torque spike

and the as-left trace after the packing replacement

does not have the breakaway

anomaly.

The inspector

noted that although the valve services

technicians

were analyzing the diagnostic traces,

they were not critically reviewing the

quality of the trace

and were not sensitive to changes

in the characteristics

of

the curves.

The inspector

concluded that if the licensee

had done

a qualitative

review of the

shape of the as-left curve to the as-found

curve they should

have

recognized

the breakaway

anomaly.

The inspector

had

a similar concern with the adequacy of diagnostic trace reviews

following the failure of another

RRS valve to close during

a differential

pressure

test

in March

1994

( Inspection

Reports

50-528/94-09,

Section

2. 1,

and

0

-22-

50-528/94-13,

Section S.l).

This particular failure was caused

by having the

wrong motor pinion gear ratio that caused

the va'lve to stroke too fast.

A

qualitative review of the as-left

and as-found traces clearly showed the

significant drop in stroke time.

The inspector

subsequently

concluded that the

licensee

did not have appropriate

acceptance

criteria because

they did not review

the relative

shape of the curves.

A noncited violation was issued

based

on the

licensee's

indication that

a qualitative assessment

of the shape of the

diagnostic trace would be included in the diagnostic test procedure.

The inspector

reviewed the current diagnostic test procedure

and noted that the

licensee still did not require

a qualitative review of the

shape

and quality of

the trace

and

a comparison of the as-left to the as-found trace.

The licensee

subsequently

determined that there

was

a

CRDR action to add the qualitative

.

assessment

to the diagnostic testing procedure,

but that it was incorrectly

closed without the action being completed.

7.2.5 Transportability of Breakaway

Torque Anomaly

The inspector

asked

the licensee

what were the most susceptible

valves to the

increased

packing loads

and if they had the

new low resistance

Argo 'packing

installed.

The licensee

determined that the most susceptible

valves

were the

RRS

valves with Limitorque SMC-04 actuators.

There are

55 of these

valves

in the

high pressure

safety injection,

LPSI,

CS and reactor coolant

systems

in all three

units.

. The licensee

had repacked all but eight of these

valves with the

new Argo

packing.

The licensee

could not find any documentation

that two of the eight

valves

had ever

been

repacked.

The licensee

evaluated

the traces for the eight

MOVs that did not have the

new

Argo packing

and noted that the spikes existed

in three of these

valves.

The

licensee

concluded that. if the value of the spike exceeded

50 percent of the

TST-.

value then the operability of the valve needed

to be evaluated.

The licensee

determined that the Unit 3 LPSI miniflow isolation Valve SIA-669 had

a spike of

about

55 percent of the

TST value.

The licensee

determined that the packing load

trended

down during maintenance

intervals

and there

was not

an operability

concern with Valve SIA-669.

The inspector

reviewed the licensee's

transportability evaluation

and agreed with

the licensee's

assessment

that there

was not

an

immediate operability concern

with any other

7.2.6

Corrective Actions

The licensee

planned to repack the eight valves that

had not been

packed with the

low resistance

Argo packing in the next available outage.

The licensee

also

agreed

to trend the breakaway