ML20149D523

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SALP Rept 50-461/97-01 for Period of 950625-970405
ML20149D523
Person / Time
Site: Clinton Constellation icon.png
Issue date: 06/23/1997
From:
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20149D520 List:
References
50-461-97-01, 50-461-97-1, NUDOCS 9707170166
Download: ML20149D523 (7)


See also: IR 05000461/1997001

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Clinton Power Station

SALP 14

(Report No. 50-461/97001) i

L INTRODUCTION

The Systematic Assessment of Licensee Performance (SALP) process is used to develop

the Nuclear Regulatory Commission's (NRC) conclusions regarding a licensee's safety j

performance. Four functional areas are assessed: Plant Operations, Maintenance,

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Engineering, and Plarl Support. The SALP report documents the NRC's observations and '

insights on a licensee s performance and communicates the results to the licensee and the

public. It provides a vehicle for clear communication with licensee management that

focuses on plant performance relative to safety risk perspectives. The NRC utilizes SALP

results when allocating NRC inspection resources at licensee facilities

This report is the NRC's assessment of the safety performance at Illinois Power's Clinton

Power Station for the SALP 14 period from June 25,1995 through April 5,1997.

An NRC SALP Board, composed of the individuals listed below, met on April 30,1997, to

review the observations and data on performance and to assess performance in i

accordance with the guidance in NRC Management Directive 8.6, " Systematic Assessment I

of Licensee Performance"

Board Chairman -

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'J. L.'Caldwell, Director, Division of Reactor Projects, Region ill

Board Members

G.-H. Marcus,' Director, Projects Directorate 1113, NRR

M. N. Leach, Acting Deputy Director, Division of Reactor Safety l

G. L. Shear, Acting Deputy Director, Division of Nuclear Meterial Safety 1

Jh PERFORMANCE ANALYSIS )

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A. Plant Ooerations >

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Performance in this functional area was adequate, a decline from performance in the

previous period. Areas of decline included procedure use and adherence, quality of

' procedures, control room conduct of operations, and personnel errors. Management was

unable to provide satisfactory guidance and oversight to the plant staff to address these

problems, especially the procedure related issues, until after significant NRC intervention.

Further, management fostered an environment which placed excessive emphasis on

minimizing equipment and unit outage ' time. The September 5,1996, reactor' recirculation

(RR) pump seal failure and follow up to that event revealc<i the extent of decline in these

areas. In March through May 1997, the licensee made improvements in_the areas noted

above'as part of a recovery program, and NRC inspectors noted improvements.

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Management failed to provide appropriate control over procedures, and was unable to l

- provide-adequate guidance on procedure use until after significant NRC involvement. This

!- deficiency resulted in a pervasive problem with procedural adherence, with some instances

. amounting to careless disregard for NRC regulations. During the September 5,1996, RR

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- pump seal failure event, operators improperly used procedures which led to a failure of the

,1 RR pump seal and other complications. The NRC identified the procedural adherence

-issues shortly after the September 5 event. The administrative procedure guiding

procedural adherence allowed staff to modify procedures without observing important

procedural change controls. Licensee management did not articulate to plant staff the

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proper level of procedural adherence control and procedure change requirements until April

.1997, after NRC inspection activities continued to identify numerous procedural adherence

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problems. Appropriate procedural adherence and procedure change policies and programs

were implemented at the end of the period.

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Some operating procedures were not appropriate for the intended evolution. The

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surveillance procedure for high pressure core spray (HPCS) valve operability allowed the

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. test to be performed under plant conditions which prevented the operators from obtaining

~ accurate test results. A reactor water cleanup pump failed upon loss of suction flow

j during a bus restoration. The pump did not trip because the procedure in use allowed

j system operation when pump trip protective features were inoperable. Improper

3 procedural instructions for defeating the reactor core isolation cooling suction transfer logic  ;

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were identified during procedure use in a plant transient. Recovery of the main condenser

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l :following a scram was significantly delayed due, in part, to system restoration procedure

{- problems. 'At the end of the period, the licensee was involved in significant procedure i

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reviews and upgrades, especially in the areas of operations surveillance, instrument

surveillance, and system operating precedures. ]

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At times management and staff placed excessive emphasis on minimizing equipment and j

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unit outage time. A plan to support an outage schedule by intentionally defeatin'g the ]

j - primary containment hatch interlock while the reactor was critical was developed by plant j

, staff and was approved by plant management early in the SALP period. NRC intervention '

was required to prevent this inappropriate action. Plant management's decision to reduce  ;

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outage time by maintaining.the plant in hot stand-by following a complicated reactor trip 1

. resulted in cycling the safety relief valves approximately 85 times. This decision increased l

r the likelihood of a relief valve sticking open, causing an uncontrolled cooldown. In an  !

. effort to maintain the reactor at power on September 5,1996, plant management

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responded to a degraded seal on the "B" RR pump in a manner which led to seal failure of

the pump, a preventable entry into emergency operating procedures, and the declaration of

an Unusual Event. After the RR pump seal failure, the unit was shut down in a protracted

manner allowing maximum time for the leakage rate to decrease below the Technical

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Specification limit, which would have allowed continued unit operations. Individual ,

' operators manipulated the.feedwater system in a manner outside of the approved i

procedural guidance to reduce outage time and expedite unit restart following the l

September 1996 event. l

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' Although conduct of operations in the control room was adequate, a number of errors

were identified. Failure to track identified leakage during the RR pump seal failure event

complicated the operating crew's ability to evaluate the proper emergency action level

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classification. An incorrectly performed valve line-up resulted in a large spill of feedwater '

which was not identified for two shifts despite repeated control room annunciator

indications of high emergency core cooling system sump levels. NRC inspectors identified

some instances of inadequate short term relief turnovers, incomplete operator logs and

rounds sheets, and informal control room communications. Further, the inspectors

identifieil one example of an operator leaving the "at the controls" area without proper

relief.

In addition, there were a number of personnel errors in activities conducted outside the

control room area. Multiple errors in preparing, implementing, and clearing a tagout

resulted in racking in a high voltage circulating water pump motor breaker contrary to the i

requirements of a tagout. An inadvertent reactor protection system trip was initiated

when an operator removed intermediate range rnonitor "E" from service with IRM "F"

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already deenergized. An operator incorrectly positioned the division 11 emergency diesel l

generator maintenance switch while performing a tagout, and the second operator failed to j

perform an adequate independent verification of the tagout. j

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Management implemented two partial work stand-downs in February 1997 to address the i

excessive number of personnel errors. Following the second February 1997 stand-down,

notable improvements in performance were observed by the NRC. Following an NRC

inspection debrief involving a March 9,1997, procedure adherence incident, the licensee l

made critical changes to procedures governing procedural adherence and the temporary

procedure change process, in concert with these actions, other operating, surveillance,

and maintenance procedures were revised to support the emphasis on strict procedural

adherence. Late in the period, inspectors observed operators making detailed changes to

procedures when surveillance such as diesel generator operability runs could not be

performed as written, then proceeding in a controlled deliberate manner to complete the

task. Management monitoring and industry peer reviews performed from March through

June 1997 resulted in improvement in control room formality and communications near the

end of the period.

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The Plant Operations area is rated Category 3. '

B. Maintenance j

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Performance in this functional area declined during this assessment period, but remained j

good overall. With notable exceptions, safety related plant equipment was well

maintained. The licensee's maintenance program appropriately identified a number of

systems requiring additional monitoring, and ensured those systems were receiving j

additional attention. However, problems with procedure adherence, procedure and work i

package quality, work control, and timely resolution of equipment concerns were evident j

throughout the period.

Timely resolution of known material condition concerns was lacking in sorra instances.

While the Clinton facility has historically performed wellin maintaining safaty systems,

some long term deGcient conditions have been allowed to exist with respect to balance-of-  ;

plant equipment. Examoles included the drywell floor drain sump monitoring system, "B"  !

circulating water purnp starting problems, and control room deficiencies. Extensive NRC l

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intervention was required to ensure adequate resolution of some material condition

deficiencies including control room correctives, feedwater check valves and safety related

breaker problems.

A number of long-standing material condition issues were pursued during the extended

refueling outage. Significant reductions were made in the number of control room

deficiencies, a problem identified in the previous SALP period, with over 400 items

resolved. Near the end of the period, operators and staff were aggressively identifying

additional items, and maintenance staff was actively working to correct them. A

concentrated effort on the outboard feedwater isolation check valves resulted in

dramatically reduced as left leakage rates. In May and June 1997, the licensee expended

considerable resources to ensure operational readiness for safety related breakers.

Although most routine maintenance activities were conducted safely, maintenance i

procedures did not always provide sufficient control of activities in some important areas. l

inadequate procedures resulted in diesel generator preconditioning during performance of I

monthly surveillance, damage to the reactor recirculation piping due to the implementation

of freeze seals, and failure to meet procedural requirements regarding Use History

Analyses, in addition, the Division 111 emergency diesel generator was inoperable for

almost a year, in part due to maintenance personnel not questioning a large discrepancy

between as-found and as-left relay calibration data, in response to the problems, the  !

licensee initiated an extensive review and revision of existing maintenance procedures. l

Deficiencies in work packages and work planning complicated some maintenance tasks. j

Work planning deficiencies included lack of contingency planning, inadequate tagouts, and l

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failure to provide parts required to complete activities. The reactor trip of April 1996 was l

'due, in part, to the work package for switchyard work which was deficient in that it failed l

to differentiate design differences in switchyard breakers and to provide an impact matrix l

to discuss the risk of this maintenance on losing a reserve auxiliary transformer at power. l

A second reactor trip in June 1996 was attributed to personnel error while performing l

maintenance in a difficult environnient.

At the end of the period, the licensee was working on improving the maintenance work

control process, improving surveillance procedures, and in ensuring proper procedure

adherence. NRC observed improved procedure adherence and that procedures were being

changed when problems were identified.

The Maintenance area is rated Category 2.

C,, Enaineerina

Overall performance in engineering was adequate. Strengths noted during the previous

SALP in self-assessment, design, and response to high-priority issues were absent from

the current SALP period. Problems with resolution of long-term issues, corrective actions,

and inconsistent management oversight that existed in the last period continued. In

addition, weaknesses in root cause investigation and corrective action, design control,

operability evaluations,10 CFR 50.59 evaluations, and procedure compliance surfaced

during the SALP period.

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Root cause investigations and corrective action for equipment problems were often not

appropriate or timely. In particular, a long term common mode failure problem associated

with hardened grease in electrical breakers and difficulties with drywall sump leakage

monitoring instrumentation noted in the last SALP were neither aggressively pursued nor

' corrected. Most notably, the licensee failed to properly evaluate the condition of 480V,

4160V, and 6.9Kv breakers even after hardened grease had been identified in the

breakers. There were examples late in the period where aggressive actions were taken.

For example, the licensee's identification and response to instrument inaccuracies in

surveillance and degraded voltage associated with the 345Kv supply through the reserve

auxiliary transformer were considered positive.

Some design activities resulted in inadequate designs and design errors resulting in

significant problems in a number of areas. Several design changes were unsuccessful and

had to be modified for important plant equipment to operate satisfactorily, including the

drywell leakage monitoring system and a regulating transformer installation in the auxiliary

power system to address degraded voltage concerns.

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The operability evaluation program lacked appropriate guidance for engineers and I

operators, the program could not easily retrieve previous evaluations, and actions i

recommended by the operability evaluations were not always complete nor were they

tracked. Some operability evaluations appeared to focus on justifying system operability

rather than objectively evaluating the situation against system operability and consistency

with the USAR. Specific examples included incorrect motor operator valve weights used ,

in seismic analyses and control room chiller auto-start load on the diesel. generator.

Safety evaluations conducted per 10 CFR 50.59 were not always performed as required

and when' performed the' evaluations were at times inadequate. Of greatest concern was

the use of engineering generated " Action Plans" which.were used to direct operators to )

perform special tests on' reactor systems without appropriate safety evaluations'or required ]

reviews. Examples of 10 CFR 50.59 deficiencies included: a special test which isolated j

the cycled condensate system from the residual heat removal (RHR) system resulting in l

RHR inoperability; disabled annunciators for demineralizer differential pressure; and the l

removal of emergency diesel generator air start system dryer check valve springs. An

. improved safety evaluation program was developed as corrective action for these

problems. The improved program included training for all engineering and operations

personnel on the purpose of 10 CFR 50.59, designation of specially trained and selected ]

individuals to review all safety evaluations, and increased emphasis on safety evaluations. 1

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A number of examples of failure to follow procedures were noted during several l

inspections. One of the most significant contributed to the RHR inoperability example

noted previously, which involved engineers indicating it was acceptable to combine steps

from disparate procedures without further review. The problem appeared to be the cause

or a significant contributor to a variety of engineering weaknesses identified during the

SALP period.

g . Late in the assessment period, the licensee took a number of steps to identify additional

i problems and correct known deficiencies. Shortly after the Operational Safety Team

( Inspeiction results were published, the licensee's Engineering Department contracted for an

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outside organization to review all engineering activities. In addition, third party focused

reviewswere conducted for areas where program improvements had been implemented,

including operability and 10 CFR 50.59 evaluations. The changes in these two specific

programs were viewed as significant improvements in the Engineering Department's

methods for conducting business.

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The Engineering area is rated Category 3.

E Plant Suocort

Plant Support performance, although adequate, declined during this assessment period

primarily due to a significant performance decline in radiation protection (RP). Deficiencies

identified in RP mirrored those identified in other areas. Specifically, problems were

identified in licensee workers' sensitivity towards and understanding of radiological

controls and alarms, and procedural adequacy and adherence. While the problems did not

result in any overexposures to licensee personnel or its contractors, the issues were

indicative of management controls not being effectively implemented in the radiation

protection area which led to a programmatic breakdown. Similar problems with

procedural adherence and understanding requirements were also evident in the Security

functional area. These problems impacted effective irnp;cmentation of several access

cortrol programs, a response activity, and some barrier control activities. Emergency

preparedness performance was good, but afsc declined. Several examples were noted

where emergency plan requirements were neither implemented in a timely manner nor well

understood by plant staff.

Radiation protection program management failed to recognize that a lack of sensitivity

towards and understanding of radiological controls and alarms existed among the work

force. This was exemplified by a number of staff actiens including: two occasions where

a worker or workers secured the supply gas to a porta! contamination monitor, rendering

the monitor inoperable; an apparent deliberate contamination of an RP technician; and

worker (s) identified to be sleeping and smoking in the radiologically controlled area, in

adoition, procedural adherence and adequacy problems contributed to several radiological

events. The events included, contamination of three workers during resin sluicing,

pressurization of a radiological waste transfer line prior to having performed an adequate

radiological survey, and inadvertent entry of three workers into the drywell in violation of a

Radiation Safety Work Plan (RSWP). Although none of the events resulted in worker

overexposures, the inadvertent entry into the drywall put the workers at risk of a

potentially lethat exposure had fuel handling resumed and a mishap occurred while they

were in the upper levels of the drywell. Some aspects of the radiation protection program

remained good, such as ALARA planning and controls, and reactor water chemistry;

however, the above problems indicated that most of the radiation protection program is in

need of significant improvement.

Security and Emergency preparedness (EP) performance declined but were considered

good. In addition to a lack of understanding of security and EP plan requirements, these

areas exhibited weaknesses similar to those in the other areas with regard to procedural

adherence and adequacy. In the security area, these problems impacted effective

implementation of several access control programs, a response activity, and some barrier

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controls activities. In the EP area, the lack of staff unde.rstanding of the EP plan was I

evidenced by a lack of classification conservatism during the September 5,1996 event.

Additionally, the EP staff was not aggressive in evaluating actual events, in updating the

Updated Safety Analysis Report, and in completing timely corrective action for identified

backup Meteorological tower instrumentation failures. How3ver, these problems did not

affect the overall excellent performance during the 1996 annual exercise.

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Following the end of this SALP period a follow up inspection into the radiation protection f

area identified the beginnings of improvements in the area. Some improvement was )

observed in the awareness among licensee staff of radiation protection requirements and

practices. Some improvements were also observed in planning and execution of work,

with an emphasis on applying lessons learned. Management expectations on procedure

adherence and supervisory oversight of work activities had been emphasized during special

training sessions.

The Plant Support area is rated Category 3.

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