IR 05000373/1997015

Insp Repts 50-373/97-15 & 50-374/97-15 on 970908-12. Violations Noted.Major Areas Inspected:Plant Operations, Maint & Engineering

ML20212B542
Person / Time
Site:	LaSalle
Issue date:	10/10/1997
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20212B511	List: IR 05000373/1997015 ML20212B505 ML20212B527
References
50-373-97-15, 50-374-97-15, NUDOCS 9710280118
Download: ML20212B542 (10)

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U.S. NUCLEAR REGULATORY COMMISSION REGIOM111

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Dockets No: 50-373, 50-374 Licenses No: NPF 11, NPF-18

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Report Nos: 50-373/97015(DRP), 50-374/97015(DRP)

Licensee: Commonwealth Edison Company Facility: LaSalle County Station, Units 1 and 2

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Location: 2601 N. 21st Road >

Marsellies,IL 61341 Dates: September 8 - September 12,1997 Inspectors: K Riemer, Dresden Senior Resident inspector M. Miller, Reactor Inspector, Region lli Approved by: A. Vegel, Acting Chief Division of Reactor Projects Branch 2 9710200118 971010 PDR ADOCK 05000373 G PDR

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EXECUTIVE SUMMARY LaSalle County Station, Units 1 and 2 NRC Inspection Report 50-373/97015(DRP); 50-374/97015(DRP)

This inspection report documents the NRC assessment of the September 4,1997, incident when the licensee was unable to comply with a required action statement of the plant Technical Specifications. The report covers a 1-week period of inspection conducted by regional and resident inspector staf Licensee performance during this event was characterized by work planning deficiencies due to a

. loss of focus on Technical Specification complianc Plant Operations

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The 1 A emergency diesel generator failed its surveillance test and as a result, the licensee was unable to comply with the minimum technical specification (TS)

requirements for operable emerger'cy core cooling systems while in operational condition 4. The inspectors identified a violation conceming failure to meet TS criteri (Section O1.1)

Maintenance a

The licensee's positive emphasis on shutdown risk came at the expense of TS compliance. As a result, the licensee was not as sensitive to the TS requirement These factors contributed to a situation where all of the station's emergency core cooling systems were technically inoperable and the licensee was unable to perform the required action statement specified in the TS. (Section M1.1)

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The licensee missed a prior opportunity to address the issue of TS compliance in the work planning process when a problem identification form documenting a similar situation was initiated in January 1997. (Section M1.1)

Enaineerinq

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Engineering personnel failed to thoroughly address the frequency meter warmup issue due to a lack of a questioning attitude. (Section E1.1)

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Report Details Summary of Plant Status

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Unit 1 was in cold shutdown for a forced outage during the entire inspection period and Unit 2 remained shut down for a refueling outage with all fuel removod. The licensee continued to keer, both units shut down to perform design basis configuration reviews and to address equipment and human performance problem I. 00erations 01 Conduct of Operations -

0 Inocerability of Technical Specification Reauired Ememency Core CooFoo Systems M.CJ11 Inspection Scope (7170Z)

On September 4,1997, the licensee entered a Division I work window with only the 1 A ,.

mmergeacy diesel generator (EDG) operable. The 0 EDG was inoperable and the 18 EDG was "available" but not " operable." Prior to cc,mpleting the Division I work window, a Technical Specification (TS) required surveillance test was run on the 1 A EDG. The diesel failed the surveillance test and as a result, the "1B" and "1C" low pressure coolant injection (i.PCI) subsystems, as well as the 1 A EDG, were declared inoperable. The licensee was unable to meet the required action statement of TS 3.5.2. The inspectors reviewed the licenseo's response to this even Observations and Findinas The initial plant ECCS configuration on September 4,1997, was in compliance with TS requirements for operational condition 4. Specifically Technical Specification 3. (ECCS Shutdown) requiced that at least two of the following shall be operable when the plant was m operational condition 4 or 5: Iow pressure core spray (LPCS) system Iow pressure coolant injection (LPCI) subsystem "A" The above two systems were Division I systems, powered by the 0 EDG. The systems were unavailable due to the Division I work windo LPCI subsystem "B" LPCI subsystem "C" The above two systems were Division ll systems, powered by the 1A EDG. The systems were operabl the high pressure core spray (HPCS) system

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The HPCS system was the Division ill system, powered by the 1B EDG, This system was "available", yet not " operable."

The Division 11 systems (items c. and d. above) were operable and the licensee met the minimum TS requirements for shutdown ECCS equipment prior to commencing the '

7 Division I work windo LaSalle Administrative Procedure (LAP) 100-47," Shutdown Risk Management Instruction," stated that an inoperable system (as defined by TS) was considered

"available"if the system was able to perform its intended safety functio On September 4,1997, the licensee operated the 1A EDG to satisfy the surveillance requirements of TS 4.8.1.1.2. The TS required (once per 184 days) that the licensee verify that the fast start voltage, frequency, and speed come up to specification within 13 seconds. Specifically, TS 4.8.1.1.2 required that the diesel reach a rated frequency of 60

+ 3.0,- 1.2 Hz within 13 seconds. The actual time to reach the required frequency was 17.95 seconds. The diesel failed to meet the surveillance acceptance criteria and was declared inoperatie. As a result, the LPCI "1B" and "1C" systems were subsequently declared inoperable. Technical Specification 3.5.2 required, in part, that with none of the above referenced systems inoperable, the licensee needed to restore at least one subsystem / system to OPERABLE with 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> or establish SECONDARY CONTAINMENT INTEGRITY within the next 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The licensee was unable to meet the required action statements of TS 3.5.2 as discussed in Section M The licensee replaced the frequency meter and reperformed the surveillance on September 5,1997. The recorded time for frequency response was 14.41 seconds. The licensee performed an operability determination and subsequently declared the 1 A EDG operable (reference Section E.1 of this report for inspector assessment of the licensee's operability evaluation). The total time that the 1 A EDG was technicaPv inoperable was approximately 34 hours3.935185e-4 days <br />0.00944 hours <br />5.621693e-5 weeks <br />1.2937e-5 months <br />. The failure to meet the TS required action statement within the required 4-hour time period is a violati~1 of TS 3.5.2 (50-373/97015-01). Conclusions The 1 A EDG failed its surveillance test and as a result, the licensee was unable to comply with ihe minimum TS requirements for operable ECCS while in operational condition 4. The inspectors identified a violation concerning the failure to meet TS criteri II. Maintenance M1 Conduct of Maintenance M Schedule issues for Work Windows Co_ntribute to TS Non-compliance Inspection Scope (62707)

During the inspection period, tho inspectors interviewed cognizant licensee personnel responsible for the planning of the ECCS work window and reviewed the equipment status in effect when the issue occurred

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I Observations and Findinna Prior to commencing the Division I work window the licensee established the following systems as either "availatee" or TS operable for decay heat removal, core coverage, and electrical power:

For Decay Heat Removal

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LaSalle System Operating Procedure (LOP)-CD 10,"Lise of Main Condenser as an Altemate Decay Heat Removal Method in Cold Shutdown." The licensee considered this method to be Availabl *

LOP-RT 13, RWCU [ reactor water cleanup) Lineup for Heat Removal." The licensee considered thh, method to be a TS equivalent method for decay heat removal, .

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"1B" loop of shutdown cooling: This method was Operabl For Core Coveraag a

LPCI subsystem "1B": This syste'n was Operabl +

LPCI subsystem "1C"; This system was Operabl .

HPCS system: The licensee considered this system Availabl 'filectrical Power

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0 EDG: This diesel was inoperable (Division I work window).

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1A EDG: This diesel was Operabl +

1B EDG: This dieselwas Availabl The licensee established the minimum required TS requirements prior to commencing work on the Division I systems. The licensee had planned for redundancies in the systems designated as "available," but did not establish contingencies for the TS required

" operable" systems. The 1B EDG and HPCS were "available"; the licensee had operated the diesel and verified that the pump performed The work remaining on the 1B EDG was relatively minor and in some casea, required only paperwork completion prior to declaring the diesol operable. Tt e standby gas treatment (SBGT) sysu:m was "available" to perform its function, but required cbsure of engineering issues and testing to demonstrate TS operabilit The licensee knew,vnd discussed, the fact that the 1 A EDG surveillance would come due during the other division work window. The licensee assumed that the 1 A EDG would pass the surveillance based on past successfu: performances. As a result of this assumption and the lack of contingency planning, the licenseo was unable to meet the TS required actions when the 1 A EDG failed the surveillance tes During the root cause investigation of the incident, the licensee identified that a prior problem identification form (PIF) 97 0575, documenting a similar occurrence, had been initiated in January 1997. In that case TS requirements were met but Operations department personnel raised concerns about being put in the situation where a TS entry was required. The licensee classified the January 1997 PIF as e scheduling concern (i.e., had the existing schedule been met the issue would not have occurred) rather than as a planning concern. The licensee missed a prior opportunity to address the issue of TS compliance in the work planning proces . _ - - _ _ _ - _ _ _ - _ _ _ _ _ _ - - _ _ _ _ _ = - - - - - - - - - - - - - - - - _ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

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l Conclusions The licensee's positive emphasis on shutdown risk came at the expense of TS

compliance. As a result, the licensee was not sensitive to the TS requirements. These y factors contributed to a situation where all cf the station's ECCS were technically iroperable and the licensee was unable to perform the required action statement (

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specified in the TS. The licensee also missed a prior opportunity to address the issue of TS compliance in the work planning proces q M1.2 Systems "Available" Durina Division I Work Window

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s a h;nection Scope (62707)

The inspectors assessed the status of the equipment "available" during the Division I work window to determine the safety significance of the even Observations and Findinas Though not technically operable, the 18 EDG was "available" to provide electrical power to the HPCS system. The inspectors reviewed the Inoperable / Degraded Equipment .

Listing with cognizant licensee personnel and determined that additional testing and documentation closeout were needed to declare the 1B EDG operable. The licensee had operated the diesel to verify it could perform and eupply electrical power to the HPCS syste The status of secondary containment was similar to that of the 1B EDG and HPCS systems. The SBGT system was "available" to perform its function. There were no physicallimitatiens that would have prevented secondary containment from performing its function. However, outstanding engineering issues and design questions would have required a lengthy amount of time to resolve and enable the licensee to declare secondary containment " operable " Conclusions Due to the redundant systems available for decay heat removal and core crurage, the inspectors concluded that the issue was of minor safety significance. The inspectors concluded that the issue was a TS compliance issu Ill. Enaineerina E1 Conduct of Engineering E Review of Failed Division 11 Emeroency Diesel Generator (EDG) Surveillance Inspection Scope (37551 and 6172#)

The inspectors reviewed the circumstances related to the failed 1 A EDG surveillance (LOS-DG-M2) on September 4,1997, the succeeding surveillance conducted on September 5,1997, and the surveillance evaluation used to determine that the EDG was operable following the second surveillanc _ _ _ _ _ _ _ _ _ _ - _ _ _ - __ _ _ - _ _ - - _ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - . - - - - - -

4 - e Objiervations and Findinot On September 4, the 1 A EDG was not able to attain the TS required frequency band within a maximum of 13 seconds. Using a meter located in the control room panel, the operators documented that the frequency was attained in 17,95 seconds. The TS also required the EDG to reach a required speed within 13 socords. The operators noted that the EDG reached the required speed in 9.58 seconds. The licensee issued PlF L1997-05525 to document the surveillance test failure, and determined that the control room meter performed erratically, and as a result replaced the mete On September 5,1997, during the post-maintenance test, the operators observed that the required frequency was reached in 14.46 seconds based on control room indicatio However, the time from a local frequency meter was 9.14 seconds. The licensee performed a surveillance evaluation to justify operability by using the local meter. The licensee determined that the control room frequency meter had a relatively long response characteristic until a steady and stable frequency reading could be obtained. This response time was significantly longer than 13 seconds. The TS did not specify which frequency meter to use to demonstrate compliance; therefore, the local indication was used to support the operability of the diesel. In addition, the licensee considered the voltage and diesel speed responses as an independent demonstratloa that the EDG was operabl The licensee also determined that the operators were not provided guidance on when to stop the stop watch in relation to the meter indication. The frequency meter received power from the EDG and was energized following the flashing of the generator field The initial response of the control room meter was to peg high and then start to decrease into the required range. As the meter decreased off the high peg, operators were unclest if the meter was recovering from being pegged or if the meter was starting to track actual frequenc The inspectors had the following comment:

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The vendor manual (Yokogawa 4555K24 701) stated in a note, " Allow ten minutes warm-up after energizing frequency meter before reading." The control room and local frequency meters for the EDGs on both units were subject to this guidance, Since the meters were energized during the EDG start sequence, the ten minute warm up was not met before using either meter to validate TS compliance. The existence of the warm up note was known to the licensee when the evaluation for the September 5,1997, surveillance test was performed. However, this information was not considered when referencing the l~al meter to justify the operabihty conclusio The inspectors were also concerned about the past operabihty of all EDGs due to the questionable frequency meters. Following further hcensee evaluation and consultation j with the vendor, the vendor provided verbalinformation that the frequency meters would respond in 2.5 seconds with an accuracy of three percent of full scale upon initial energization. The 10-minute period was required for one percent accuracy. This instrument inaccuracy did not affect the results of previous test l l

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s in addition to the surveillance problems encountered, the frequency meters used for all the EDGs were not consistent. Some meters had a frequency ranges of 58 to 62 Hz, some had 55 to 65 Hz and others had 45 to 65 Hz. Some meters pegged high when the generator field was flashed and others pegged low, in the de-energized state, some meters pegged low, some high, and one stopped at 60 H Conclusions The frequency meters had been used to validate TS compliance for many years, although the vendor manual clearly raised questions about the meters suitability. When the licensee was faced with the second failure of the surveillance, they became aware of the meter warm up question but did not address it in the evaluation. The failure to address the warmup isste when identified, demonstrated J poor questioning attitude on the part .

of engineering. Additionally, the Operations department accepted the evaluation without questioning the limited scope of the initial call. Despite the quality of the evaluation, the inspectors considered the EDG operable based on the vendors supplemental informatio The mixture of frequency meter ranges and response characteristics placed an additional human factors problem on the operators. While the m.eter characteristics for this surveillance contributed to the surveillance problem, having differently responding meters for the operators to deal with, added to the overall potential of an operational errors. The licensee identified the inconsistencies between the meters but listed it under"Long Term" solutions to prevent recurrence of this even VI. Manaaement Meetinas X1 Exit Meeting Summary The inspectors presented the results of these inspections to licensee management listed below at an exit meeting on September 12,1997. The licensee acknowledged the findings presented. The inspectors asked the licensee if any materials examined during the inspection should be considered proprietary. The licensee identified non _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ - _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ - _ - - _ _ _ - _ _ _ _ _ _ - - - _ - _ - . -

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f PARTIAL LIST OF PERSONS CONTACTED -

Comed W. Subalusky, Site Vice President S. Smith, Unit 2 Plant Manager J. Mcdonald, Quality . id Safety Assessment (Q&SA) Manager J. Pollock, Support Engineering Supervisor R. Chrzanowski, ISEG Supervisor J. Bums, Operations Support Supervisor *

R. Palmieri, System Engineering Manager W. 'Jekielski, Shift Manager T. Gupana, QC Supervisor J. Bally Restart Manager B. Riffei, Corrective Actions Manager H. Vinyard, EMD Master Mechanic NRC A. Stone, Acting Branch Chief, Region 111 DRP K. Riemer, Senior Resident inspector, Dresden Station D. Calhoun, Acting Senior Resident inspector, LaSalle Station Present at exit meeting on September 12,1997,

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INSPECTION PROCEDURES USED IP 37551 Onsite Engineering IP 61726 Surveillance Observation IP 62707 Maintenance Observation IP 71707 Plant Operations ITEMS OPENED, CLOSED, AND DISCUSSED 9PEl

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50 373/97015-01 VIO Failure to meet TS action as required UST OF ACRONYMS USED EDG Emergency Diesel Generator HPCS High Pressure Core Spray LAP LaSalle Administrative Procedure LOP LaSalle System Operating Procedure LOS LaSailo Operating Surveillance LPCI Low Pressure Coolant injection LPCS Low Pressure Core Spray NRC Nuclear Regulatory Commission PIF Problem identification Form RHR Residual Heat Hemoval SBGT Standby Gas Treatment System TS Technical Specification VIO Violation

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