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Insp Rept 50-331/98-06 on 980318-20.Violations Noted.Major Areas Inspected:Circumstances Surrrounding Removal of Sys from Service,Review of Selected Procedures & Records & Interviews W/Personnel Involved W/Removing Sys from Service
	ML20217L721
Person / Time
Site:	Duane Arnold
Issue date:	04/28/1998
From:	Leach M; NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:	;
Shared Package
ML20217L046	List: ML20217L041; ML20217L053; ML20217L721;
References
	50-331-98-06, 50-331-98-6, NUDOCS 9805040285
	Download: ML20217L721 (12)
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U. S. NUCLEAR REGULATORY COMMISSION

REGIONlli

Docket No: 50-331

License No: DPR-49

Report No: 50-331/98003(DRS)

Licensee: IES Utilities Inc.

200 First Street S.E.

P. O. Box 351

Cedar Rapids, IA 52406-0351

Facility: Duane Arnold Energy Center

Location: Palo, Iowa

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Dates: March 18 - 20,1998

Inspectors: M. Bielby, Reactor Engineer, Team Leader..

J. Larizza, Reactor Engineer

L. Collins, DAEC Senior Resident inspector (Acting)

M. Kurth, DAEC Resident inspector

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Approved by: M. Leach, Chief, Operator Licensing Branch

Division of Reactor Safety

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9905040295 990428 i

PDR ADOCK 05000331 l

G PDR 1

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EXECUTIVE SUMMARY

Duane Amold Energy Center

NRC Inspection Report 50-331/98006

This special inspection reviewed operational and engineering aspects of the licensee's decision

to remove the manual rod control system from service and rely on the safety-related trip

function to insert control rods while the plant was operating at power. During this time, the

reactor was in a "coastdown" condition with all control rods fully withdrawn. Modifications were

performed on the reactor manual control system (RMCS) to remove spurious rod blocks and

nuisance alarms in the control room. The plant was about two weeks from a refuel outage and

plant management did not want these spurious rod blocks and alarms to interfere with an

orderly plant shutdown.

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Operations

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The reduction of nuisance rod blocks and alarms to prevent unnecessary operator

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distractions showed good safety focus; however, the lack of Probablistic Risk

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Assessment calculations for online RMCS maintenance led to a narrowly focused

decision to perform the maintenance online. The Duane Arnold Energy Center technical

specifications do not address RMCS operability at power. (Section 01.2)

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Operators were not timely in their recovery of normal manual rod control as indicated by

the length of time the RMCS was allowed to remain out-of-service, and the time that

elapsed prior to conducting Post Modification Testing. (Section 01.3)

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The shift turnover sheets reflected the current status of the RMCS modifications. l

However, the Operating Log and Operations Shift Supervisor Log did not accurately j

document the status of reactivity control equipment and indicated a lack of attention to

detail. The six failures to make required log entries documenting the operational status

of the RMCS were considered a violation of 10 CFR 50, Appendix B, Criterion V.

(Section 01.4)

Engineering

. The RMCS modifications appeared to correctly address the identified equipment

problems. However, the post modification testing failed to verify the proper operation of

all components associated with the equipment modifications and was considered a

violation of Duane Arnold Energy CenterTechnical Specifications. (Section E1.2)

. A 50.59 screening correctly identified that a safety evaluation for the RMCS

modifications was not required. However, no 50.59 screening addressed removal of the

RMCS from service during plant power operation. The inspectors concluded that further

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inspection was required to determine if a violation of 10 CFR requirements had

occurred. This is considered an unresolved item. (Section E1.3)

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Report Details

1. Operations

'01 Conduct of Operations

01.1 General Comments

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During the month of ^v' arch 1998, the Duane Arnold Energy Center (DAEC) reactor was j

in a "coastdown" condition with all control rods fully withdrawn Spurious rod blocks and

nuisance alarms were being generated by the reactor manual control system (RMCS). .

Station management did not want these spurious rod blocks and alarms to interfere with l

an orderly plant shutdown and directed technicians to install modifications in the RMCS I

to repair the cause of the rod blocks and alarms. To successfully install the

modifications, the RMCS would have to be taken out-of-service. This special inspection

reviewed the licensee's decision to remove the RMCS from service while the plant was

operating at power and the decision to rely on the safety-related trip function to insert 1

control rods during the RMCS outage.

01.2 Schedulina of RMCS Modifications i

a. Insoection Scone (71707)

The inspectors conducted interviews and reviewed the licensee's preparations for the

RMCS modifications. The inspectors reviewed the following: l

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Operations Instruction 856.1, " Reactor Manual Control System."

. Technical Specification 3.3.A.

. Technical Specification surveillance requirement 4.3.A.

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Corrective Maintenance Action Request A34101. " Install Surge Suppression To ;

Prevent Rod Control Relays From Producing Period Alarms in SRMS (Source J

Range Monitors] Due to Electrical Spiking"

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CMAR A39036," Remove 14 Rod Sequence Control System Relays No Longer

Required For System Operation To Reduce Nuisance Control Rod Blocks"

. CMAR A40308, " Change Two Resistors And Reinstall Two Varistors To Reduce

Average Power Range Monitor Noise Interference From Reactor Manual Control

System Solid State Timer"

b. Observations and Findinas

Three separate Corrective Maintenance Action Request (CMAR) work packages for the

RMCS modifications were generated by the licensee's engineering department and

submitted for implementation. The CMARs were approved and sent to scheduling. The

process for scheduling the CMARs included a review of the risks and benefits of

implementing the CMARs by a Scheduling Team. The scheduling team consisted of an

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operations shift supervisor (OSS), a scheduler, a work foreman, a system engineer

. group leader, and a probabilistic risk assessment (PRA) representative.

l The scheduling team considered the following before scheduling the RMCS

l~ modifications during power operation:

l . The plant was approximately two weeks from a scheduled refuel outage and

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plant management did not want spurious RMCS generated rod blocks and 1

nuisance alarms to interfere with an orderly shutdown. l

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There was no available PRA calculation for online maintenance on the RMCS.

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Online RMCS maintenance had not been factored into the licensee's

Probabilistic Safety Assessment mode!.

!- . Technical Specifications did not directly address removal of the RMCS from

service with the plant at power.

. Operations Instruction 856.1, Section 5.0, " Shutdown Of The RMCS," had a

NOTE that stated, "The RMCS should be fully operational whenever the plant is

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operating or whenever control rod movement is desired. All or portions of the q

RMCS can be shutdown for repair or maintenance as necessary". 1

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The normal method of moving and positioning control rods during the RMCS

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outage would be unavailable; the safety-related trip function would be

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l . Operating crews would be briefed to manually trip the reactor in response to any

! abnormal reactivity event.

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. The reactor would be in "coastdown" with all control rods fully withdrawn and no

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requirement to move control rods for flux shaping.

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. The RMCS had been previousty taken out-of-service while the plant was

operating at power to complete RMCS repairs.

The licensee's team concluded the benefits involved in perforir.ing the RMCS

modifications during power operation and the contingency action developed for

addressing reactivity events made the risk acceptable.

Although the licensee observed that RMCS operability at power was not directly

j addressed in Technical Specifications, the inspectors noted that RMCS operability at

t- power was implied in the following Technical Specifications:

. Technical Specification 3.3.A.2.d which stated that the operators will have the

ability to perform actions to recouple an uncoupled control rod, and to perform

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coupling checks on control rods when they reach the fully withdrawn position.

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t . . Technical Specification surveillance requirement 4.3.A.2.f(l) stated a requirement

to exercise each fully withdrawn control rod once per week.

c. Conclusions

The reduction of nuisance rod blocks and alarms to prevent unnecessary operator

' distractions showed good safety focus; however, the lack of PRA calculations for online

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RMCS maintenance led to a narrowly focused decision to perform the maintenanco '

online.

01.3 Seauence of Events for Performance of RMCS Modifications

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a. Insoection Scone (71707)

L The inspectors reviewed the sequence of events related to removing the RMCS from

service during power operation on two different occasions between March 13 and 17,

1998.' The inspedors reviewed the following documents:

. Control Room shift tumover sheets and Operating and OSS logs for

March 13-18,1998

. Equipment Tagout Number 9802, " Reactor Manual Control System"

.b. Observations and Findings '

Friday, March 13,1998:

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. The RMCS was disabled at 10:54 a.m. to begin modifications of 24 rod control relays

under CMAR A34101 (see section E1.2). The RMCS was not tagged out-of-service

because the affected relays could be removed, modified, tested, and reinstalled

individually. During each relay removal control room operators were unable to select

and move control rods using the RMCS. Performing the individual relay modifications _ in

this configuration minimized the time required to restore the system to operability. The

actual work took approMmately eight hours. The post modification test (PMT) of the

RMCS was completed at approximately 1:33 a.m. on March 14,1998.

Monday, March 16,1998:

The RMCS was tagged out-of-service at 9:42 a.m. by removing three power supply

fuses, and repositioning a rod movement control switch. Modifications were performed

on two relays under CMAR A40308. During this configuration, control room operators

were unable to select and move control rods using the RMCS. The licensee estimated

the time to restore RMCS operability would be 15-20 minutes. The restoration included

completion of immediate work, tag clearance, reinstallation of power supply fuses, and

repositioning of the rod movement control switch. The actual work duration was

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approximately three hours. No PMT was performed and the RMCS remained tagged

out of service through the following day until the final modification was completed.

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. Tuesday, March 17,1998:

Modifications were performed to remove 14 rod sequence control system (RSCS) relays !

and two associated annunciators under CMAR A39036. The work involved installation

of jumpers and retermination oileads. The licensee estimated it could restore the

RMCS to operability (clear tags, reinsiaii power supply fuses, and back out of the work

in progress)in approximately 15-20 minutes if it became necessary. However, it was

later determined that during one stage of the modification, the time to restore the RMCS ,

to operability would be about three to five hours. l

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The previously installed RMCS tagout was accepted at 3:41 a.m. and the actual work

duration was approximately eight hours. The tags were cleared at 1:20 p.m. Since the

RMCS was taken out-of-service at 9:42 a.m. on March 16, the RMCS had been

continuously out-of-service for over 27 hours3.125e-4 days <br />0.0075 hours <br />4.464286e-5 weeks <br />1.02735e-5 months <br />. The PMT was completed at 10:22 p.m.

During the time the RMCS was out-of-service the licensee was relying on the safety-

related reactor trip function to insert control rods for any reactivity event that may have

occurred.

c. Conclusions

Operators were not timely in their recovery of the normal manual rod control as

indicated by the length of time the RMCS was allowed to remain out-of-service, and the

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time that elapsed prior to conducting PMTs. '

01.4 Ooeratina and Ooerations Shift Suoervisor Loo Entries

a. Insoection Scooe (717071

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The inspectors reviewed the control room Operating Log, the Operations Shift l

Supervisor (OSS) Log, and associated tumover sheets for the March 12 - 17,1998, time

period. The inspectors also reviewed the following procedures:

. ACP 14.10.1, " Conduct of Operations" Revision 16

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ACP 1410.3, " Operating Logs," Revision 3

b. Observations and Findings i

The inspectors noted that ACP 1410.3, Section 3.2, required entries in the Operating

Log each shift for equipment removed and returned to service. The inspectors also

noted that ACP 1410.3, Section 3.3, required entries in the OSS Log each shift for

maintenance on major equipment.

On March 13,1998, both control room logs identified the start of RMCS modification

CMAR A34101. The individual turnover sheets for the Shift Manager, Nuclear Shift

Operations Engineer, and OSS appropriately identified the status of the RMCS j

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modifications throughout the various shift reliefs. Both control room logs identified the l

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start and completion of the PMT for the RMCS. However, neither the Operating Log nor 3

the OSS Log identified completion of CMAR A34101, nor the RMCS return to service.

The two failures to make required log entries documenting the operational status and

authorized work of the RMCS were considered violations of 10 CFR 50, Appendix B,

Criterion V. (VIO 50-331/98006-1a and -1b(DRS))

! On March 16,1998, the individual tumover sheets for the Shift Manager, Nuclear Shift

Operations Engineer and OSS appropriately identified the status of the RMCS .

throughout the CMAR A40308 modifications. However, the Operating Log did not {

contain an entry for removal of the RMCS from service, and the OSS Log did not identify {

a start or completion time for CMAR A40308. The two failures to make required log

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sntries documenting the operational status and authorized work of the RMCS were

considered violations of 10 CFR 50, Appendix B, Criterion V. (VIO 50-331/98006-1c

and -1d(DRS))

On March 17,1998, the individual tumover sheets for the Shift Manager, Nuclear Shift

Operations Engineer and OSS appropriately identified the status of the RMCS

throughout the CMAR A40308 modifications. Both control room logs identified the start

and completion of the PMT for the RMCS. However, the Operating Log did not contain

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an entry for restoration of the RMCS to service, and the OSS Log did not identify a start

or completion time for CMAR A39306. The two failures to make required log entries

documenting the operational status and authorized work of the RMCS were considered

violations of 10 CFR 50, Appendix B, Criterion V. (VIO 50-331/98006-1e and -1f(DRS))

c. Conclusions

The shift turnover sheets reflected the current status of the RMCS modifications. The

Operating Log and OSS Log did not accurately document the status of reactivity control

equipment and indicated a lack of attention to detail. The six failures to make required

log entries documenting the operational status of the RMCS were considered a violation

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of NRC requirements.

Ill. Enaineerina

E1 Conduct of Engineering

E1.1 General Comments

The inspectors reviewed the engineering department's involvement in evaluation and

modification testing of the reactor manual control system while the plant was operating

at power. The inspectors conducted personnel interviews and reviewed selected

portions of certain procedures and representative records.

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E1.2 Review of RMCS Corrective Maintenance Action Reauests

a. Insoection Scoce

The inspectors assessed the work packages for performing RMCS modifications, and

reviewed the PMT in detail with the system engineer. The following were also reviewed

by the inspectors:

. Technical Specification 6.8.1

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Maintenance Directive MD-024, " Post Maintenance Testing Program,"

Revision 12

b. Observations and Findings

The licensee prepared three CMARs to address nuisance rod blocks and annunciators

associated with operation of the RMCS. The work was considered an Engineered

Maintenance Action, and the PMT was required by MD-024. The inspectors noted that

Technical Specification 6.8.1 required that procedures addressing testing requirements

for equipment that could have an impact on the nuclear safety of the facility shall be

implemented. MD-024 required that post maintenance testing be performed, if

appropriate, following corrective maintenance on components regardless of Quality

Level to verify: the ability of the system or component to perform its intended function,

the original deficiency was corrected, and no new problems were created.

CMAR A34101 was initiated September 12,1996, to eliminate circuit noise from 12 rod

control relays that produced " spiking" of source range monitor indications. The identified )

solution was to install surge suppression resistor-capacitor (RC) filters across the coil of l

each rod control relay. The PMT was identified as STP 3.1.3-01. The inspector

requested a detailed review of STP 3.1.3-01. During the review, the system engineer

acknowledged that the PMT did not test the " Continuous insert" relay (C11-K018)

subsequent to completion of the modification. This was considered a violation of DAEC

Technical Specifications. (VIO 50-331/98006-02a(DRS)).

CMAR A39036 was initiateo October 15,1997, to eliminate nuisance rod blocks from 14

RSCS relays that were no longer required to be functional by Technical Specifications.

Additionally, the two associated annunciators were not required to be operable. The

identified work was to install jumpers, reterminate leads, and subsequently remove the

relays and annunciators. The PMT was identified as performance of" Rod Adjustment

Sheets, Version 98-005, A2 Sequence."

CMAR A40308 was initiated December 8,1997, to eliminate electronic noise

interference with te average power range monitors (APRMs) during rod movements at

reactor power levels less than approximately 12%. The interference caused nuisance

APRM downscale annunciators. The identified resolution was to install smaller resistors

in the RC filter for each of two relays, and reinstall a previously removed (CMAR

A36763) metal oxide varistor across each coil of the same two relays. The two relays

were part of the RMCS solid state timer that provided timing sequences to operate the

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control valves on the hydraulic control units for control rod movement. The PMT was

identified as performance of" Rod Adjustment Sheets, Version 98-005, A2 Sequence."

The inspector requested a detailed review of the PMT. During the review, the system I

engineer acknowledged the PMT did not test the " solid state timer malfunction" l

computer points subsequent to completion of the modification. This was a second

example of a violation of DAEC Technical Specifications. (VIO)(50-331/98006-

02b(DRS)).

c. Conclusions 1

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The RMCS modifications appeared to correctly address the identified equipment

problems. However, the post modification testing failed to verify the proper operation of

all components associated with the equipment modifications and was considered a

violation of DAEC Technical Specifications.

E1.3 Taking RMCS Out-Of-Service During Power Ooeration j

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a. Insoection Scooe i

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The inspectors reviewed the details of removing the reactor manual control system from

service for an extended period of time with the plant operating at full power.

b. Observations and Findings

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The licensee performed a 10 CFR 50.59 review of the three CMARs which determined I

that a safety evaluation for the RMCS modification was not required. However, the

screening did not reference the removal of the RMCS from service during normal power

operation.

The licensee's Technical Specifications did not address the rod control system

operability directly. Technical Specification 3.3.A.2.d implied that an operator will have

the ability to perform actions to recouple an uncoupled control rod and to perform

coupling checks on control rods when they reach the fully withdrawn position.

Technical Specification surveillance requirement 4.3.A.2.f(l) implied that the rod control

system will be operable since it contains a requirement to exercise each fully withdrawn

control rod once per week.

The licensee's Updated Final Safety Analysis Report (UFSAR) Chapter 7.7.3.1, " Power

Generation Objective," stated "The objective of the reactor manual control system is to

provide the operator with the means to make changes in nuclear reactivity so that

reactor power level and power distribution can be controlled." Furthermore, UFSAR

Chapter 15.1.2, " Loss of a Feedwater Heater," stated "If power exceeded the normal

full-power flow control line, the operator would be expected to insert control rods to

return the power and flory to their normal range. If this was not done, the neatron flux

could exceed the scram setpoint causing a scram."

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.. On March 13,16 - 17,1998, the licensee operated the RMCS in a manner not described

in UFSAR Sections 7.7.3.1 and 15.1.2. A written safety evaluation had not been

performed to determine whether or not the change to the system configuration specified

in the UFSAR involved an unreviewed safety question. Specifically, no safety screening

evaluation was performed for the removal of the RMCS from service with the reactor at

power.

c. Conclusions

A 50.59 screening correctly identified that a safety evaluation for the RMCS

modifications was not required. However, no 50.59 screening addressed removal of the

. RMCS from service during plant power operation. The inspectors concluded that further

inspection was required to determine if a violation of 10 CFR requirements had

occurred. This is an unresolved item. (URI 50-331/98006-03(DRS)).

V. Management Meetings

X1 Exit Meeting Summary

The inspectors presented the inspection results to members of licensee management at the

conclusion of the inspLtion on March 20,1998. On April 8,1998, a telephone exit was

conducted to inform the licensee that a potential violation item discussed during the exit on

March 20,1998, would become an unresolved item. The licensee acknowledged the findings

presented.

The inspectors asked the licensee whether any materials examined during the inspection

should be considered proprietary. No proprietary information was identified.

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PARTIAL LIST OF PERSONS CONTACTED

Licensee Exit. March 20.1998

J. Bjorseth, Maintenance Manager

D. Curtland, Operations Manager

J. Easton, Procedures Supervisor

J. Franz, Senior Vice President Nuclear Generation

B. Hopkins, PSA Engineer

K. Huber, Systems Engineering Supervisor

M. Huting, Program Engineer Supervisor

K. Kleinheinz, Scheduling

D. May, Maintenance Process Support Sup.

M. McDermot, Engineering Manager

D. Mienke, Nuclear Design

K. Morgan, Quality Assurance

R. Murrell, Licensing

K. Peveler, Regulatory Performance Manager

J. Probst, Engineering Maintenance Rule Coordinator

J. Quimby, l&C Project Engineering

C. Sullivan, Systems Engineering

G. Van Middlesworth, Plant Manager

Telechone Exit. Acril 8.1998

M. Davis, Assistant Operations Supervisor

l R. Murrell, Licensing

K. Peveler, Regulatory Performance Manager

G. Van Middiesworth, Plant Manager

D. Wilson, Assistant Vice President Nuclear Generation

l M. Bielby, Reactor Engineer

L. Collins, DAEC Senior Resident inspector (Acting)

M. Kurth, DAEC Resident inspector

J. Larizza, Reactor Engineer

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INSPECTION PROCEDURE USED

IP 71707 Conduct of Operations

ITEMS OPENED, CLOSED, AND DISCUSSED

Opened

50-331/98006-01 VIO Inadequate operating ';g entries for work on RMCS

50-331/98006-02 VIO Inadequate post modi cation testing on RMCS

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50-331/98006-03 URI Inadequate 50.59 serr sning for taking RMCS out-of-service

during power operation

Closed

None

Discussed '

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ML20217L721

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