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Insp Rept 50-461/92-20 on 921027-1207.Violation Noted.Major Areas Inspected:Plant Operations,Radiological Controls,Maint & Surveillance,Security,Engineering & Technical Support, Safety Assessment & Quality Verification
	ML20126B499
Person / Time
Site:	Clinton
Issue date:	12/09/1992
From:	Hague R; NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:	;
Shared Package
ML20126B480	List: ML20126B476; ML20126B492; ML20126B499;
References
	50-461-92-20, NUDOCS 9212220112
	Download: ML20126B499 (12)
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U.S. NUCLEAR REGULATORY COMMISSION

REGION III

Report No. 50-461/92020(DRP)

Docket No. 50-461 License No. NPF-62

Licensee: Illinois Power Company

500 South 27th Street

Decatur, IL 62525

facility Name: Clinton Power Station

Inspection At: Clinton Site, Clinton, Illinois

Inspection Conducted: October 27 - December 7, 1992

Inspectors: P. G. Brochman

F. L. Brush

M. J. Miller

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Approved By: / />/'//9v

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lague/ Chief Date

MReactor

ichard Prb

L./jects Section IC

Inspection Summary

Inspection from October 27 through December 7.1992. (Recort No.

50-461192020(DRP))

Areas Inspected: Routine, unannounced safety inspection by the resident and

region based inspectors of licensee actions on previous inspection findings,

plant operations, radiological controls, maintenance and surveillance,

security, engineering and technical support, safety assessment and quality

verification, and management meetings.

Results: Of the seven areas inspected, no violations or deviations were

identified-in six areas: one violation was identified in the remaining area:

(entry into an operational condition with required equipment _ inoperable -

paragraph 3.c). One unresolved item was identified concerning the analysis of

potential fires in the offgas charcoal absorber beds (paragraph 2.b).

The following is a summary of the licensee's performance during this

inspection period:

Plant Operations

- The ' reactor operators response on entry into the power-to-flow

instability region was excellent. A manual scram was promptly made and

no' power oscillations were observed.

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- The plant entered Operational' Condition 2 with the drywell and

containment H,/0, analyzer inoperable.

Maintenance and Surveillance-

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Additional failures of the reactor feedwater pump throttle linkages

occurred. The licensee replaced the bronze bushings with tapered roller

bearings.

- An excellent effort by the maintenance and engineering personnel

identified a manufacturing defect in the number one service air

compressor's fourth stage seal air hole. This problem had caused

excessive oil leakage, vibration, and also affected motor bearings.

- analyzer was a

Contributing to the

failure to utilize operations

written problem

procedures withrecogn

and not the H,/0,izing that

reprogramming a microprocessor was performing maintenance.

Security

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A review of the fitness for duty program did not identify any

deficiencies.

Enaineerina and Technical Suonort

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An excellent analysis was performed by the engineering staff of

overheating of electrical relays utilizing a ganged configuration. The

scope of the analysis was expanded beyond the specific concern

identified in an NRC-information notice and was very thorough.

- A review of the accident analysis section of the Clinton Updated Safety

Analysis Report (USAR) indicated that an offgas charcoal adsorber fire-

had not been adequately analyzed for the potential release of fission

products to the environment; and that non-conservative assumptions

appeared to have been utilized.

Safety Assessment and Quality Verification

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The quality of a third-party audit of the quality assurance (QA)

organization was excellent. Several improvement items and one weakness 1

were identified,

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DETAILS

1. Persons CEDIACitd

Illinois Power Company (IP)

J. Perry, Senior Vice President

J. Cook, Vice President and Manager of Clinton Power Station (CPS)

J. Miller, Manager - Nuclear Station Engineering Department (NSED)

R. Wyatt, Manager - Quality Assurance

F. Spangenberg, III, Manager - Licensing and Safety

R. Morgenstern, Manager - Training

J. Palchak, Manager - Nuclear Planning and Support .

L. Everman, Director - Radiation Protection

P. Yocum, Director - Plant Operations

W. Clark, Director - Plant Maintenance

R. Phares, Director - Licensing

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K. Moore, Director - Plant Technical

W. Bousquet, Director - Plant Support Services

C. Elsasser, Director - Planning & Scheduling

S. Hall, Director - Nuclear Program Assessment

J. Sipek, Supervisor - Regulatory Interface

D. Korneman, Director - Systems and Reliability, NSED

R. Kerestes, Director - Nuclear Safety and Analysis

J. Langley, Director - Design and Analysis, NSED

The inspectors also contacted and interviewed other licensee and

contractor personnel during the course of this inspection.

Denotes those present during the. exit interview on December 7, 1992.

2. Action on Previous Inspection Findinos (92702)

a. (Closed) Unresolved Item (461/91018-01(DRP)): Blown fuse in

standby gas treatment system (SBGT) affects other' components. On

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August 28, 1992, a fuse failed in a load-driver for the SBGT

relays. This condition was alarmed and the-licensee replaced the

blown fuse within 3 hours3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months . A subsequent evaluation indicated that

multiple components in Division I would have failed to actuate on

valid high radiation or loss of coolant accident signals. The

inspectors had requested the licensee evaluate the reportability-

of this event, the system's conformance.to General Design

Criterion (GDC)~23, and the information contained in the

annunciator response procedures.

The licensee's analysis concluded that this event was not

reportable since no technical specification action statements were

exceeded, redundant isolation valves existed, or. equipment

received start signals from other process parameters. The

licensee concluded that while selected valves would not fail to

their safety position, on a loss of power,- that the safety

function was designed against a single failure. Therefore, the

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failure of one division would not prevent the operation of the

other and the plant's design was in conformance with GDC 23.

The licensee did revise its annunciator response procedures and

operator training to recognize that the failure of this fuse would

affect more components than the SBGT system. Based on the

licensee's corrective actions and evaluations, the inspectors have

no further concerns. This item is considered closed,

b. (Closed) Open Item (461/92010-03(DRP)): Questions on the design

of the offgas charcoal adsorber system.. The inspectors had asked

three questions on design information for the offgas system, which

was contained in the'Clinton Updated Safety Analysis Report

(USAR). The licensee had responded to the first question and was

still evaluating questions two and three. Question one related to

- the fact that USAR Table 11.3-5 did not consider the possibility

of a charcoal fire in the " equipment malfunction analysis".

The licensee stated that a charcoal adsorber fire was an event

rather than an equipment malfunction. And that this ev'at was

analyzed in USAR Chapter 15. The inspector reviewed the analysis

in Section 15.7.1.1 and identified that the assumptions used

appeared to be non-conservative and did not reflect the .

possibility that a high temperature charcoal fire might result in

the release of fission products to the environment.

In USAR Section 15.7.1.1.5.2, " Design Basis Analysis," a seismic

event was considered as the only conceivable event which would

cause significant system damage; and therefore release of

radioactive material to the environment. A fire was not

considered a reasonable possibility. However,-a high temperature

fire had already occurred at Clinton and the inspector considered

the question moot as to whether a fire was possible.

Given that a charcoal fire is a credible event, the following

assumptions necd-to.be considered. .First, any radioactivity which

had been adsorbed by the charcoal would be released as the carbon

matrix was consumed; rather than being retained, as the USAR

assumptions stated. Second, the source term used for the analysis

might not include the proper quantity of long term fission

products retained by the charcoal at the end of plant life.

Third, and more importantly, to extinguish _ the fire, nitrogen gas

(N,) would be used to purge the charcoal . beds. However, to purge

the N, into the beds an outlet path must be _available.

Consequently, any radioactivity which was released would have an

exhaust path to the environment. +

The inspector qu'estioned if-the USAR analysis accurately addressed

this accident and whether releasing the maximum possible, end of

life, quantity of fission products stored in the charcoal adsorber

beds-would result in offsite doses outside of the-limits of 10 CFR

Part 100, " Reactor Site Criteria." This issue will be followed as

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Unresolved Item (461/92020-01(DRP)). The issues raised-by the

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open item all remain open; however, they will be tracked under

this unresolved item; consequently, this open item is considered

closed.

No violations or deviations were identified.

3. Plant Qnerations

The unit operated at power until 3:12 a.m. on November 22, 1992, when

the unit was manually tripped due to entry into the power-to-flow

instability region. The reactor was taken critical on November 24.

The reactor operated at power for the remainder of the report period,

a. Onsite Event Follow-uo (93702)

The inspectors performed onsite follow-up activities for an event

which occurred during November 1992. Details of the event and the

licensee's corrective actions developed through the inspectors

follow-up are provided below:

Manual Reactor Trio yoon Entry Into the Power-to-Flow Instability '

Region

At 3:12 a.m. on November 22, 1992, with reactor power at 75

percent, the "B" reactor feed pump (RFP) minimum flow valve failed

open, diverting feedwater flow from the reactar. The "A" RFP was

out of service to inspect its throttle linkage bearings. The

diverted feedwater caused reactor level to drop from the normal

level of 36 inches [91.4 cm] to approximately 28 inches [71.1 cm].

The reactor recirculation flow control valves (FCV) then ran back

to their minimum position when reactor water level reached the

Level 4 setpoint - 30.8 inches [78.2 cm] - coincident with one RFP

in operation. The FCV runback decreased reactor power into the

power-to-flow instability region. The reactor operator

immediately tripped th_ reactor per procedure. No power

oscillations were observed. All systems- responded as designed and

the unit was stabilized in hot standby.

The minimum flow valve failed open due to a loss' of instrument air

(IA). The copper IA supply line failed immediately upstream of

the fitting connecting it to the valve's operator. The licensee

believed this was due to vibration induced stress hardening.- The

IA lines to both the "A" and "B"'RFP minimum flow valves were

replaced using stainless steel flexible hoses. The licensee had

developed a generic modification, FECN 24523 - in 1989 - to

replace copper IA lines after they' fail. The licensee intends to ,

inspect other copper IA lines before the end of the next refueling

outage and replace susceptible IA lines before a failure occurs.

The licensee was also evaluating the operation of the flow control

runback to determine if it could be set to a higher value or if it--

could be disabled if the plant is already operating on one RFP.

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The response of the reactor operators was excellent in assessing

the situation and promptly scramming the unit before any

oscillations began. Operations personnel had recommended before

the downpower that control rods be inserted below the 80% rod line

on the power-to-flow map; however, management had chosen not to do

this. If this had been done the reactor would not have entered

the power-to-flow instability region when the FCV ran back;

removing the need for the scram. During the subsequent repairs to

the B RFP, control rods were left inserted below the 80% rod line.

The inspectors will perform further reviews of this event after

the LER is issued.

b. Operational Safety (71707)

The inspectors observed control room operation, reviewed

applicable logs, and conducted discussions with control room

operators. During these discussions and observations, the

operators were alert, cognizant of plant conditions, attentive to

changes in those conditions, and took prompt action when

appropriate. The inspectors verified the operability of selected

emergency systems, reviewed tagout records, and verified the

proper return to service of affected components.

Tours of the circulating water screen house and auxiliary,

containment, control, diesel, fuel handling, rad-waste, and

turbine buildings were conducted to observe plant equipment

conditions, including potential fire hazards, fluid leaks,

excessive vibrations, and to verify that maintenance requests had

been initiated for equipment in need of maintenance.

The inspectors observed plant housekeeping and cleanliness

conditions and verified implementation of radiation protection

controls and physical security plan.

c. Ooerational Condition Chance With a Hydrocen/0xvaen Analyzer

Inocerable

At 8:56 p.m. on November 23, 1992, the reactor entered Operational

. Condition (OC) 2, "Startup". At 9:20 a.m. on November 24, 1992,

! operations personnel discovered that the Division II drywell and

! containment H,/0, analyzer was inoperable. On November 22, 1992,

! operations personnel had requested that maintenance personnel run

the Division II H /0, analyzer through its calibration cycle to

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verifyitwasworkingproperly. To accomplish this task,

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maintenance personnel had to reprogram the microprocessor - which

I controlled the analyzer - to execute a calibration cycle at that

time, rather than the usual time of 8:10 a.m. each day. This task

was successfully completed and at 10:30 a.m. maintenance personnel

! then reentered the commands to return the monitor to its normal

l routine. However, the maintenance technician who performed this

i task made a personal error and transposed two numbers in the

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commands he entered. This rendered the analyzer inoperable. This

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condition was not recognized until November 24, 1992, after the

unit was started up.

There were several causes to this event:

1. The controller for the H,/0, analyzer was not designed

to support the performance of a calibration check on

demand, but required that the controller's software be

reprogrammed.

2. Neither operations nor maintenance personnel

recognized that reprogramming the controller was

performing mair' aance on the analyzer. Consequently,

administrative ,,rocedures, which would require that

the monitor be declared inoperable and

post-maintenance testing be performed, were not

implemented.

3. The maintenance personnel performing this task did not

utilize any written instructions or procedures.

4. There was no independent verification to assure the

quality of the sof tware commands was maintained.

5. Operations personnel did not observe the printout on

November 23, 1992, which would have indicated that the

monitor was inoperable. Technical specifications did

not require that a channel check be performed daily,

but only monthly on the H,/0, analyzers.

Technical specification (TS) 3.0.4 required that entry into an

operational condition shall not be made unless the condition for

the limiting condition for operations are met. Technical

specifications 3.3.7.5, Table 3.3.7.5-1, Instrument 7, required ,

that both the Division I and II containment and drywell H /0,

analyzers be operable in OC 1, 2, and 3. Thefailuretobaveboth

H,/0, analyzers operable during entry it,to DC 2 was a violation of

technical specification 3.0.4 (416/92020-02(ORP)).

From a listing of the causes of this event it was apparent that

the licensee's " software QA" program had failed to prevent this

problem. The licensee had recently revised its software QA

program and had just issued it before this event occurred;

however, the new program had not been implemented. In its

response to the violation, the NRC requested the licensee address

whether its newly issued software QA program adequately controls

activities on this type of safety-related computer.

As corrective action the licensee has developed procedures to

change the programming on the controller and briefed maintenance

and operations personnel on this event. The inspectors will

review this event further after the LER is issued.

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No deviations were identified. One violation was identified.

4. Radiolooical Controls (71707)

External Surveys

As part of routine monitoring, the inspectors performed a radiological

survey to verify accuracy of the licensee's survey maps. The results'of

the monitoring were found to be in close agreement with the licensee's

surveys.

No violations or deviations were identified.

5. tiaintenance and Surveillance (61726 & 62703)

a. Observations Of Work Activitin

Station maintenance and surveillance activities of both

safety-related and nonsafety-related systems and components listed

below were observed or reviewed to ascertain that they were

conducted in accordance with approved procedures, regulatory

guides, industry codes or standards, and in conformance with

technical specifications.

Document & tivity

023534 Votes Testing of Valve 1SXO97A

D25008 Div I DG Output Breaker Inspection

D26498 Clean / Inspect Valve IE51-F068

D30476 Rebuild Horizontal Fire Pump

D31903 Repair Controller for valve IWS01818

D32476 Replace bearing on ISA01C Air Compressor

D33015 Replace valve IE51-F324A

D36798 Votes Testing of Valve IE12-F049

7911.35 Calibrate Alnor Dosimeters-

9080.01 Diesel Generator Operability Test

9404.02 Valve Stroke Timing IE51-F068, F077, F078

9433.16 RCIC storage tank level channel IE51-N035A

calibration

b. Reactor Feedwater Pumo (RFP) Maintenance

The 8 RFP had been taken out of service to inspect the condition

of the bronze bushings in the throttle linkage. This was done as

part of the licensee's extensive efforts to resolve the problem

with the throttle linkage binding. The licensee had previously

l done extensive machining to repair the bushings and had committed

to inspect the condition of-the bushings after 150 hours0.00174 days 0.0417 hours 2.480159e-4 weeks 5.7075e-5 months of

operation (see Inspection Report 461/92012, Paragraph 4.c). When

the throttle linkage was initially inspected, maintenance

personnel noted that the linkage was difficult to move by hand.-

Examination of the bushings showed accelerated wear and pitting of

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both the bushings and the steel journals. The licenser. replaced

the bushings with new ones for both the A and B RfPs.

The unit was subsequently restarted on November 24, and with less

than 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months of service the B RFP throttle linkage again locked

up. The pump was isolated without inducing a transient.

Examination of the bushings indicated severe galling and damage to

bushings and damage to the journals. Based on the lack of success

in resolving the problems with the bushings, the licensee

replateu the bronze bushings with double tapered roller bearings.

This was ai m done for the A RFP.

The licensee initiated a failure analysis of the bronze bushings,

which was still in progress at the end of the inspection period.

After replacing the bushings in the A RFP the licensee experienced -

problems with the hydraulic control actuator for the throttle

linkagc. The problem had not been corrected by the end of the

report period and the inspectors will perform further evaluation

in a subsequent report on this problem and the results of failure

analysis.

c. Service Air Comoressor Activitit:i

The licensee rebuilt the ISA01C service air compressor (SAC) and

[ subsequently observed that the oil seal on the fourth stage failed

prematurely. The licensee investigated this problem and

discovered that the manufacturer had improperly drilled a seal air

port hole in the fourth stage and that the hole was slightly

misaligned. Maintenance personnel filled in the hole and drilled

, a new '-e.

The itcensee also inspected the bearings on the air compressor's

motor, in the past, the licensee would repair the SAC after

. problems were observed, return the SAC to service, and .

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subsequently nocice that the motor bearings were damaged. This

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time the licensee inspected the motor bearings before the SAC was

returned to service and discovered the outboard bearing was

damaged. The SAC was successfully returned to service.

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The inspectors noted excellent efforts of the maintenance and

engineering personnel in identifying the misdrilled seal air port

hole and the interrelationship between problems in the compressor

and the motor bearings.

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No violations or deviations were identified.

6. Security

Etness for Duty Proaran)

The inspector reviewed the licensee's fitness for duty (ffD) records for

positive tests in the first half of 1992. The records were complete and

provided information on the substance involved and actions taken by the

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licensee on the individual's access to Clinton station. There was an

absence of documented information on whether impaired individuals, who

had access to the plant, had been involved with any safety-related

activities; and if so, was there any impact on those activities,

llowever, the FfD program manager had met with plant management in each

case and discusscd the impact, in all of the cases, there was no impact

on safety related systems, structures, or components. Following

discussion with the inspector, the licensee decided to document these

discussions and consolidate them with the other positive test

information. I

No violations or deviations were identified.

7. [naineerina and Technical Suppgri

The inspectors reviewed the licensee's evaluation of the applicability

of HRC Information Notice (IN) 92-27, " Thermally Induced Accelerated

Aging and failure of ITE/Gould A.C. Relays used in Safety-Related

Applications." The IN addressed using class J10 relays mounted in a

horizontal " ganged" arrangement. The licensee reviewed the installation

for all class J relays and determined that Clinton had two instances of

normally energized class J13 relays, in a ganged configuration.

However, this arrangement had been tested by another utility and no

3roblems were identified. The inspectors concluded that the licensee

lad expanded the scope of its analy:,;is beyond the requirements of the IN

and performed a thorough evaluatia. The inspectors have no concerns on

this issue.

No violations or deviations were identified.

8. Safety Assesignt and Ouality Verification

a. Self Assessment Capability (40500)

The inspector reviewed a third-party audit of the quality

assurance (QA) organization. The audit aapeared to be very

thoroigh and identified strengths and wea(nesses. Findings from

the audit were as follows: Several weaknesses were noted in the

quality engineering's inspection planning. Strengths were noted

in the level of training of quality engineers and the niorning

turnover meeting. Quality verification personnel were

knowledgeable of inspection progrsm requirements.

The audit recommended that the matrixes for the audit schedule,

Appendix B, and technical specifications be conse);o; ted to assure

proper coverage. The licensee's response stated the its present

structure was adequate. The certification of auditors was found

to be current and audit checklists were thorough and supported

audit findings. Problems and concerns were properly identified on

condition reports or recommendations. The overall conclusion was

that the audit and surveillance program was effective in assessing

QA program implementation.

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However, problems were identified in procurement QA. Procurement

document reviews were marginally adequate. The QA reviews did not

incit le drawings or specifications. The QA acceptance of items .

was ut. satisfactory. The primary problem was a lack cf objective

evidence in support of testing / inspections required to demonstrate

the acceptability of items. Contributing to this was a lack of

attention to detail. This problem was most apparent in commercial

grade dedications. The licensee's response noted that this

problem had been identified earlier. The licensee concluded that

the previous corrective action had failed to resolve the problem

and was developing new corrective actions.

The inspectors will review this issue in a subsecuent report after

the licensee's corrective actions are implementec and a followup

audit is performed.

b. Licensee Event Report follqw-up (90712 & 92700) .

Through direct observation, discussions with licensee personnel,

and review of records, the following licensee event reports (LER)

were reviewed to determine that the reportability requirements

were fulfilled, immediate corrective action was accomplished, and

corrective action to prevent recurrence had been accomplished in

accordance with technical specifications.

LIB Title

461/92001 Main Transformer "B" phase fault resulted in a

Turbine Trip and Reactor Scram.

461/92002 Reactor Feed Pump Control Lockup resulted in a

low Reactor Water Level Trip.

No violations or deviations were ide,itified.

9. tLanagmquLlicetina

Mr. J. S. Ferry, Senior Vice President and members of his staff met with

Mr. A. B. Davis, Regional Administrator, and members of his staff on

November 10, 1992, at the Clinton Power Station. Topics incluJed

efforts to improve the corrective action and Generic Letter 89-10

programs, maintenance program performance, and the nuclear program

strategic plan.

10. Unresolved Itemi

Unresolved items are matters about which more information is required in

order to ascertain whether they are acceptable items, violations, or

deviations. One unresolved item disclosed during the inspection is

discussed in paragraph 2.b.

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I' t pectors met with the licensee representatives denoted in

pa. ; graph I at the conclusion of the inspection on December 7,1992.

The inspectors surnarized the purpose and scope of the inspection and

the finding;. The inspectors also discussed the likely informational

content of the inspection report, with regard to documents or processes

reviewed by thi inspectors during the inspection. The licensee did not

identify any such documents or processes as proprietary.

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