IR 05000331/1997014

Insp Rept 50-331/97-14 on 970822-0927.No Violations Noted. Major Areas Inspected:Licensee Operations,Engineering,Maint & Plant Support

ML20199G233
Person / Time
Site:	Duane Arnold
Issue date:	11/12/1997
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20199G223	List: IR 05000331/1997014 ML20199G217
References
50-331-97-14, NUDOCS 9711250129
Download: ML20199G233 (15)

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U S. NUCLEAR REGULATORY COMMISSION REGION 111 [

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Docket No: 50 331'  ;

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License No: DPR 49 i

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Report N /97014(DRP) t r

Licensee: lES Utilities In i

- 200 First Street P. O. Box 351  :

Cedar Rapids, IA 52406 0351 [

Facility: Duane Arnold Energy Center ;

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1-Location: Palo, Iowa -

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Dates: August 22. depternber 27,1997

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inspectors: C. Lipa, Senior Resident inspector :

M. Kurth, Resident inspector -

I Approved by: Michael J. Jordan, Chief Reactor Projects Branch 5

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EXECUTIVE SUMMARY Duane Arnold Energy Center NRC inspection Report No. 50 331/97014(DRP)

This inspection report included resident inspectors' evaluation of aspect? of licensee operations, engineering, maintenance, and plant suppor The inspectors identified several examples where effective teamwork resulted in prompt and appropriate resolution of emergent equipment issues. Identification and resolution of problems was goed. Examples included early identif; cation of a steam leak in the steam tunnel, identification of an inadequate surve!; lance test, and identification of an error in the Mark i analysi Operations

• The conduct of operations continued to be professional, with appropriate focus on safet (Section 01.1).

• There was good teamwork between engineering, operations, and maint6 nance departments to resolve emergent equipment issues. (Section 01.2).

• The prompt plant shutdown to repair a leak on a drain line off main steam line demonstrated conservctive operating philosophy and focus on plant safet (Section 01.2).

• The r6moval of equipment froni service during the plant shutdown was deliberate and well controlled. (Section 01.2)

• The startup and shutdown was characterized by careful planning and was accomplished without error. (Section Ot.2)

Maintenance

• The licensee identified a surveillance test that did not meet Technical Specifications requirements. The licensee conservatively declared the valves inoperable and promptly tested them satisfactorily. (Section M1.2).

• Emergent equipment issues were appropriately resolved. Repair efforts were well coordinated between departments. (Section M2.1).

Enaineerina

• Engineering persnnnel provided effective support for emergent issues and operability evaluations were thorough. (Section E1).

• The inspectors identified that the hand switch for ECCS keep fill pump was not labeled, listed in system standby readiness line up, or shown on the piping diagra (Section E1.1).

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• T he inspectorm identified that the HPCI discharge pressure went high aff scale during a HPCI surveillance test Subsequently, the licensee identified that the pressure was higher than that assumed in a calculation that demonstrated the lo;ds would not exceed allowable values. (Section M1.3)

MAssessment and Quality VenficatiOD e Self assessment activities were effective. The licensee resolved several problems that were identified through detailed reviews and a questioning approac (Sections 07, Mi.2, E1.1)

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Resort Details  ;

Summary of Plant Status j

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At the beginning of the inspection period, the plant was operated at 100 percent power. On -

A9aust 22,1997, a power reduction was initiated to bring the plant to a cold shutdown conditio ;

The, shutdown was scheduled when a circulating water system tube leak in the main condenser i was discovered. After repair, the plant startup was commenced on August 27. On September 9  ;

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another plant shutdown was initiated due to concerns with a steam leak in the steam tunnel. The leak was due to a cracked weld joint on a 1 inch pipe re:lucer off the "A" main steam lin Following successful repair, the olant startup was commenced on September 13,1997. The

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plant was operated near full power for the remainder of the inspection perio l. Operations ,

' 01 Conduct of Operations 01,1 - General Comments (71707) i The inspectors conducted frequent reviews of plant operations. This included observing routine control room and in plant activities, attending shift turnovers and crew briefings, and performing panel walkdowns. The conduct of operations was professional and focused on safety, with appropriate management oversight. Noteworthy observations are detailed in the sections belo .2 Plant Startups and Shutdown Insoection Scoce (71707) .

The inspectors monitored licensee activities during two reactor startups and one shutdown. This included observation of portions of each shift's activities, management and reactor engineering briefings, operator use of procedures, and coordination between control room and in plant operator . : Following repair of main condenser tube leak, the licensee commenced a reactor startup on August 27,199 ,

e On September 9,1997, the plant w1s shutdown to repair a steam leak on a drain line off the "A" maln steam lin .. Following repair of the steam leak, the licensee commenced reactor startup on -

September 13,196 b, Observations and Findinas The inspectors observed thorough briefings involving station management and reactor engineers prior to power changes and control rod movements. Activities were well  ;

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- coordinated between and among control room operators and in plant operators. - The inspectors noted appropriate procedure usage and management oversigh .

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During the plant shutdown on September 9,1997, the licensee acted promptly to begin a power reduction following identification of a cracked weld on a drain line off the *A' main steam fir.e in the steam tunnel. The inspectors observed good teamwork between operations, maintenance, and engineering personnel. Engineering and maintenance personnel entered the steam tunnel to assess the crack and determine a repair pla Based on a review of crack location and configuration, engineering personnel expressed concerns that the crack was potentially fatigue related and could quickly become large Subsequently, operations began a fast power reduction in accordance with integrated Plant Operating Instruction, IPOl 4. The inspectors observed the power reduction and manual scram at approximately 23 percent power. Prior to the scram, the shift manager briefed personnel on their panel assignments and parameters to monitor. Activities were well coordinated and performed in a controlled manne During startup activities on September 13,1997, problems with several stuck control rods were appropriately resolved. The licensee had some difficulty with control rods that were stuck at posWion 00. Operators appropriately entered Abnormal Operating Procedure AOP 255.1, * Control Rod Movement / indication Abnormal." The procedure allowed increasing control rod drive (CRD) drive water pressure from normal pressure of 250 265 pounds per square inch differential (psid) up to 310 350 psid. In all cases but one, the increased drive water pressure was sufficient to move the control rod and then pressure was restored to normal. In one case, control rod number 38-23 did not move evon with CRD drive water pressure at 350 psid. The inspectors observed good engineering personnelinvolvement to determine the basis for the 350 psid maximum value in the procedure. The licensee contacted General Electric for technical assistance and concluded that pressure could be increased up to 500 psid maximum. The licensee completed a safety evaluation applicability review form and the procedure was revise Subsequently, control rod 38 23 was successfully moved with pressure at 450 psi The inspectors had one concern during the startup on September 13. The inspectors observed one instance when the operations shift supervisor (OSS) was manipulating a valve hand switch on the control panels. This appeared to be contrary to plant management expectations. Based on previous discussions with plant management, the inspectors understood the expectation to be that the OSS would remain in a supervisory role and not operate equipment. Also, the conduct of operations procedure (ACP 1410.1)

specified that the OSS shall remain in a supervisory role and refrain from manipulating equipment. Plant management explained that in this case, the OSS was coaching the operators on a difficult to adjust valve and the shift manager was in the control room providing adequate oversight. The licensee initiated Action Request 972283 to evaluate the wording of the conduct of operations procedure. The inspectors had no safety concerns with this specific instance and it was characterized as an observatio '

c. Conclusiomi The inspectors concluded that the plant startups and plant shutdown were well controlled evolutions. The startup and plant shutdown was characterized by careful planning and was accomplished without error, There was good teamwork between oporations, maintenance, and engineering personnel to resolve emergent issues. The removal of equipment from service during the plant shutdown was deliberate and well controlle The prompt plant shutdown to repair the steam leak demonstrated conservative operating philosophy and focus on plant safet . . . - . - - - -- - - .-- .- . ._-.- . .._~ .- -. - - - . - - ---

t 0 Reactor Water Cleanuo System isolation Inspection Scope (71707. 72700,93702) .

i On September 21,1997, the licensee informed the inspectors that an engineered safety features (ESF) actuation had occurred. The reactor water cleanup system isolated on a ,

high differential flow signal. This was reported in accordance with 10 CFR Part 50.7 The inspectors reviewed the event, including root cause and corrective action l T Observations and Findinas .

On September 21.1997, while removing the "A" reactor water cleanup (RWCU) pump from service, a Group V isolation (RWCU isolation) occurred. System isolation valves closed as expected in response to the isolation s;gnal. The isolation signal was received when the indicated differentin flow exceeded the setpoint of 40 gallons per minute differential (gpmd).

Subsequently, the instrument technicians determined that return flow transmitter FT 2748 was degraded. When flow was reduced to zero during system isolation, the differential flow summer received a negative signallarge enough to trip the 40 gpmd setpoint. The licensee replaced FT 2748, tested it satisfactorily, and returned the RWCU system to servic The inspectors observed prompt response by engineering and maintenance personnel to determine the cause of the problem and take appropriate corrective actio Conclusions The inspectors concluded that the licensee properly rasponded to and resolved the ESF actuatio .

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02 Operational Status of Facilities and Equipment 0 Engineered Safety Feature System Walkdowns (71707)

The inspectors used Inspection Procedure 71707 to walk down accessible portions of the following ESF systems:

eStandby diesel generators

• Residual heat removal system eCore spray (CS) system

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' Equipment operability, material conditloa, and housekeeping were acceptable in all cases. One discrepancy regarding a hand switch for the RHR/CS keep fill pump is discussed in Section M2.1. This was brought to the licensee's attention and correcte The inspectors identified no substantive concems as a result of these walkdown ,

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07 Quality Assurance in Operations 0 Licensee Self Assessment Activities (71707)

During the inspection period, the inspectors reviewed multiple licensee self assessment activities, including:  !

e Action Request Screening Meetings l e Operations Committee Meeting l

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The inspectors concluded that the self assessment activities observed were effectiv ;

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IL Maintenance

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M1 Conduct of Maintenance l M1.1 General comments ,

' insoection Scope (62707) (61726)

The inspectors observed or reviewed all or portions of the following maintenance activities and surveillance tests: ,

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• Torus water levelinstrument calibration, STP 42F006-SA i

e High pressure coolant inlection (HPCI) simulated automatic actuation, STP 45D003 A e Control building chiller valve maintenance e Primary containment isolation valve testing, STP 47B009-Q i

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e Secondary containment integrity, STP 47J001.CY e Daily instrument checks, STP 42A001

• Generator output breaker CB 4290 repair Conclusions The inspectors verified that testing was performed in accordance with applicable procedures, that applicable Technical Specifications were met, and that results were acceptable. Followup actions for observations by the inspectors during the HPCI testing are discussed in Section M1,3 belo M1.2 - Inadequate Technical Specifications (TS) Required Surveillance Procedure insoection Scoce (61726)

During the inspection period, the licensee identified one case where TS surveillance requirements were not properly completed. The inspectors reviewed the TS requirements, immediate corrective actions, proposed long-term corrective actions, and results of testing. The inspectors verified that applicable limitirJ conditions for operation (LCO) were me . t r

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b, Observations and Findinos The bcensee was prompted by an in Service Testing (IST) program commitment to I review the surveillance test procedure for the primary containment isolation system ,

(PCIS) valve functional test. The purpose was to ensure proper testing according to  !

American Society of Mechanical Engineers (ASME) requirements. This review revealed  !

that certain PCIS valves were not being stroke timed in accordance with TS l

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requirements. The PCIS valves were associated with the post accident sampling system '

and the hydrogen / oxygen containment monitoring system. To satisfy the TS requirement, closure times needed to be measured. However, since 1991, closure times were not established nor measure ;

in 1991, the operating license was amended to remove stroke timo values from the TS  ;

. requirement. However, the TS still required testing and timing the valves. Prior to 1991, the TS closure times for the valves were considered to be not applicable (N/A).

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The licensee declared the valves inoperable and revised surveillance test procedure STP 478009-Q to time the valves in accordance with ASME allowable times (less than '

2 seconds), The surveillance testing was performed and all 20 valves operated within the ASME time limit Conclusions The inspectors concluded that the licensee took a conservative approach in declaring the valves inoperable upon discovery and promptly performed the necessary stroke time ,

testing to verify their operability. This is considered an unresolved item (URI) pending further review of test results and the significance of the finding (URI 50 331/97014 01(DRP)).

M1.3 Hioh Pressur3 Coolant inlection (HPC0 Surveillance Test issues Insoection Scoce (61726)

On September 23,1997, the inspectors observed the annual HPCI simulated automatic

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actuation surveillance test. This included a review of applicable Technical Specifications, a review of the Surveillarice Test Procedure STP 45D003 A, attending pre test management briefing and radiation protection briefing, observing the test, and reviewing the result b. - _ Observations and Findings The inspectors observed that the briefings were appropriate and emphasized radiological conditions, attention to detail and procedure adnerence. The test was well coordinated between control room operators, in plant operators, and instrument and control technicians. The test involved two automatit HPCI initiations and one automatic HPCI tri The inspectors identified one concern during the test when the discharge pressure gauge initially pegged high (above 1500 pounds per square inch gauge (psig)). This occurred 8 ,

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r during the second HPCI initiation. The inspectors had noted during previous HPCI tests that discharge pressure initially increased to approximately 1400 psig and then settled out at approximately 1200 psig. The .nspectors were concemed that the pressure went off scate and questioned operations management and the system engineer following the test to determine if the system had been over pressurized. The system engineer reviewed the special parnmeter monitoring traces that were routinely taken during HPCl tests and inium;ed ine inspectors that the peak pressure was approximately 1675 psig. Although this pressure was higher than the value used as an input in calculation 409-P80-311, Revision 2, the licensee was able to show that there was adequate margin to the stress limits and that there was no operability concem in this case. in calculation 409-P80 311, the engineer had assumed a peak pressure of 1590 psig, calculated the expected loads, i and then determined the margin to the stress limits based on the loads As a result of the inspectors' questions, the licensee identified the need to formally revise the calculation to use a higher peak pressure as an input valu The system engineer was also able to explain wny the peak pressure was higher in this instance, compared to other tests that the inspectors had observed. During the second start of the HPCI system, the system was fully lubricated, which allowed for faster starting than during the routine quarterly tests. Past data showed that during other testing which involved a second HPCI start, peak pressures were approximately 1675 psig. Although the inspectors noted good engineering personnel followup to the inspectors' observations of September 23,1997, the inspectors were concerned that this issue was not pursued in the past. Peak pressures up to 1675 psig occurred in the past; however, the calculation had not been revised and still assumed a peak pressure of 1590 psig. The licensee documented the occurrence on Actien Request (AR) 971966 and planned to revise the calculation. The inspectors planned to review the revised calculation. Pending further review, this issue is tracked as inspection follow-up item (IFI) 50 331/97014 02 (DRP).

During the quarterly HPCI surveillance test performed on August 20,1997, the inspectors noted that the test was secured due to increasing suppression pool temperature. The test was later reramed and completed satisfactorily. The operators had entered Emergency Operating Procedure EOP 2, * Primary Containment Control" at 95'F and maximized torus cooling. The torus temperature continued to ri:,e to 100*F at which point the test was secured. The inspectors reviewed the Technical Specifications (TS) and verified that the operators performed the appropriate actions and that TS requirements were met. The inspectors planned to review this issue further to ensure that the torus response was consistent with the design assumptions. This will be tracked as IFl 50 331/97014 03 (DRP).

c. Conclusions The inspecters verified that HPCI surveillance test results were satisfactory and the TS requirements were met. The licensee's operability evaluction for the high HPCI discharge j pressure was considered acceptable. Two inspection followup items were opened to ensure further review of the two testing issues discussed abov l

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M2 Maintenance and Materiel Condition of Facilities and Equipment  !

M Plant Materiel Condition i inspection Scope (62707)

T' 0 inspectors noted that ther a were five emergent equipment issues during the spection period in each case, the inspectors observed appropriate licensee response  ;

to repair and to determine the root cause. The examples are listed below: ,

• During the plant startup on August 28,1997, the licensee attempted several times before being successful at closing the generator output l*reaker (CB4290) to synchronize to the grid. The inspecte s observed the licensee's troub',tshooting efforts and inspection activities and noted that planning was well coordinated between operations personnel and electrical maintenance personnel and that  !

problem identification and resolution was prompt. (AR970697)

+ On September 8,1997, the "C" River Water Supply pump did not start due to the

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failure of the breaker to close. The inspectors observed that troubleshooting '

plans were well developed and included vendor participation. No obvious defects were identified. The breaker was removed from service and sent to the manufacturer for further testing. No defects were identif:ad by the manufacture The breaker will be reassembled, tested, then sent back to Duane Amold as a spare. (AR972089)

• On September 8,1997, a steam tunnel entry was made due to an ir, creasing *

I trend on a steam tunnel temperature instrument. A fatigue crack was identified on a 1 inch pipe weld off of the "A" main steam line. The reactor was shutdown on September 9 and engineering personnel prepared a modification package to r3 configure the piping on all 4 main steam lines to prevent recurrence. The inspectors observed that conservative and prompt actions were taken to repair the steam pipe crack upcn discovery. (See Section 01.2 for details) Also, the operator who identified ins increasing temperature trend showed a strong questioning attitude. (AR972091)

• On September 12,1997, containment atmosphere dilution valve, SV43328, was opened during surveillance testing. Shortly after opening, the open indication was

%st. Afterward, the upstream pressure regulators would not function properl The affected penetration was isolated and the valve was removed and sent offsite to be rebuilt. The inspectors verified that TS requirements were met. (AR972098)

• On September 21,1997, a reactor water cleanup isolation occurred. The cause was determined to be a failed flow transmitter. The inspectors observed the  !

licensees root cause determination process and appropriate actions taken to remedy the failed transmitter. See Section 01.3 for details.(AR972270)

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! Conclusions The inspectors concluded that repair efforts were prompt and well coordinated between  !

operations, maintenance, engineering, ar.d radiation protection departments. Engineering personnel provided effectiva support for emergent issue {

l l11 Engineering E1 Conduct of Engineering Inanection Scone (37551)

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The inspectors evaluated engineering involvement in resolution of emergent materist condition problems and other routine activities. The inspectors reviewed areas such as operability evaluations, and root cause analyses. The effectiveness of the licensee's controls for the identhication, resolution, and prevention of problems was aiso examine j Conclusions s

- As discussed in Sections M2.1 and O1.2, the inspectors noted that engineering personnel i provided effective support for emergent equipment issues. As discussed in Sections E1.1 and M1.3, operability evaluations were considered thorough and no concerns were note '

E Incorrect Assumption in Mark 1 Analysis insoection Geone (37551)

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The licensee informed the inspectors of an issue regarding the Mark 1 analysis calculations for core spray piping penetrations. The inspectors reviewed the licensee's operability evaluatio . Observations and Findinas On September 12,1997, during reanalysis of core spray piping penetrations to support the emergency core cooling system suction strainer modification, the licensee idenJied an error in the original analysis. The piping had been analyzed without including the additional weight of water in the piping. Engineering personnel documented the issue on AR 970296 and provided an operability evaluation to the operations department. The operability evaluation was based on revised calculations, which showed that the updated ,

loads were withir, ASME code allowable limits. The inspectors had no concerns with the licensee's resolution of this issu Conclusions

- The inspectors concluded that the licensee promptly documented and evaluated this Issue upon identificatio ;

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E3 Engineering Procedures and Documentation E3,1 - - Residual Heat Removal / Core Spray (RHR/CS) Keepfill Pump not Addressed in Operating

Instruction (Oli Line-uo Inspection Scoce (71707. 37551)

As discussed in Gection 02.1, the inspectors performed system walkdowns and observed work activities in the plant. Also, the inspectors reviewed plant equipment and design configurations against the plant drawings and applicable procedures, One discrepancy was identifie b, Observations and Findinas The inspectors identified that the local hand switch for the RHR/CS keepfill pump was not labeled. Upon further review, the inspectors found that the hand switch position was not part of the standby readiness line up section for Operating Instruction (01) 149, " Residual Heat Removal System". In esponse to this finding, the licensee determined that the associated plant drawing needed to be updated to include the hand switch and initiated AR972083. The licensee was currently in the process of updating the drawing, Conclusions The inspectors were concerned that the hand switch for the RHR/CS keepfill pump was not properly characterized in the standby readiness line-up section of the RHR OI, and was not included in the system drawing. The inspectors observed that the licensee appropriately entered the findings into their corrective action (AR) process. The inspectors had no further concerns, IV Plant Suonort There were no concems in the plant support are V. Manaaement Meetinag X1 Exit Meeting Summar/

The inspectors presented the inspection results to members of licensee management at the conclusion of the inspection on September 26,1997. The licensee acknowledged the findings i presented. The inspecters asked the licensee whether any materials examined during the I inspection should be considered proprietary. No proprietary information was identifie I l

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PARTIAL. LIST OF PERSONS CONTACTED 1.lsnaus- -

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J. Franz, Vice President Nuclear:.

Gc Van Miudiesworth, Plant Manager L _

r 4 '.R. Anderson, Manager, Outagn and Support -i

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- J; Bjorseth, Maintenance Superintendent -

. D. Curtland. Operations Manager _ _

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R. Hite, Manager, Radiation Protection .

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M. McDermott, Manager, Engine.> ring

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K. Peveler, Manager, Regulatory Performance _

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INSPECTION PROCEDURES USED IP 37551i - Onsite Engineering '

IP 61726: Surveillance Observation IP 62707: - Maintenance Observation -

IP 71707: . Plani Operations IP 71750: Viant Support .

IP 92700: Onsite Followup of Written Reports of Nonroutine Events at Power Reactor Facilities IP 32901: Followup Operations IP 92902: Followup - Engineering _

IP 92903:- Followup - Maintenance lP 93702: Prompt Onsite Response to Events at Operating Power Reactors

'lTEMS OPENED, CLOSED,- AND DISCUSSED Opened

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URI Inadequate PCIS surveillance testing 50 331/97014-02_ IFl High HPCI pressure during testing 50-331/97014 03 IFl High torus temperatures during HPCI testing

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LIST OF ACRONYMS USED ACP Administrative Control Procedure AOP Abnormal Operating Procedure ASME American Society of Mechanical Engineers CFR Code of Federal Regulations CRD Control rod drive CS Core spray DAEC Duane Arnold Energy Center EOP Emergency Operating Procedure ESF Engineeied safety feature HPCI High Pressure Coolant injection IFl Inspection followup item IP inspection procedJre IPOl - Integrated Plant Operating Instructions-IR Inspection report IST In-service testing LCO Limiting Condition for Operation NRC . Nuclear Regulatory Commission Ol Operating Instruction OSS Operations Shift Supervisor PCIS Primary containment isolation system PSID Pounds per quare inch differential PSIG - Pounds pers square inch gauge RHR Residual heat removal RWCU Reactor water cleanup STP- Surveillance Test Procedure TS Technical Specification URI Unresolved item 15