IR 05000413/1998003
| ML20247B868 | |
| Person / Time | |
|---|---|
| Site: | Catawba  |
| Issue date: | 04/30/1998 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML20247B864 | List: |
| References | |
| 50-413-98-03, 50-413-98-3, 50-414-98-03, 50-414-98-3, NUDOCS 9805110099 | |
| Download: ML20247B868 (28) | |
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U.S." NUCLEAR REGUL'ATORY COMMISSION
REGION II
Docket Nos: 50-413, 50-414
. License Nos:
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Report Nos.: 50-413/98-03. 50-414/98-03 Licensee: Duke Energy Corporation Facility: Catawba Nuclear Station. Units 1 and 2 Location: 422 South Church Street Charlotte, NC 28242 Dates: February 22 - April 11,1998 Inspectors: D. Roberts, Senior Resident Inspector R. Franovich, Resident Inspector M. Giles, Resident Inspector (In Training)
Approved by: C. Ogle, Chief Reactor Projects Branch 1 Division of Reactor Projects
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Enclosure
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9805110099 990430 PDR ADOCK 05000413 0 PDR
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EXECUTIVE SUMMARY
' Catawba fluclear Station'. Units 1 and 2 :
NRC Inspection Report 50-413/98-03. 50-414/98-03 This integrated inspection included aspects of licensee operation maintenance, engineering, and plant support. The report covers a 7-week l period of resident inspectio Ooerations
- The Unit 2 annulus ventilation system was inoperable for five and one-half hours on March 12-13. 1998, due to personnel error during the issuance and implementation of a compensatory action form prior to performing work on a lower containment airlock access door. Th licensee's root cause attributed the event to an inadequate process for determining what compensatory actions were required to perform work on the door. The fact that three statements in the compensatory action i manual essentially prohibited work on the door under the given i circumstances was not developed in the licensee's root cause analysi The event was reported.to the NRC in accordance with regulatory requirements. (Section 01.3)
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- The licensee performed a good assessment of the compensatory action
. program which provided insightful findings and has initiated corrective actions to improve the overall program and its implementation. (Section
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< * An administrative error led operators to unknowingly vent an inservice reactor coolant pump seal injection filter, resulting in momentarily low seal injection flow to all four RCPs. The error highlighted a long-standing design flaw associated with RCP seal injection filter differential pressure indication and annunciation in the control roo Licensee personnel had previously worked around the indication deficiency by relying on administrative means to determine which filter was in service, but'had not included this issue in the o)erator work around program nor had measures been taken to correct t1e instrumentation design flaw. (Section 04.1)
- The observed active simulator exam was challenging and required operators to demonstrate their abilities in recognizing and handling i- degraded plant conditions. Although the observed scenario did not l' challenge operators on the use of Technical Specifications, licensee
! management indicated that other scenarios have involved and will f continue to involve performance measures in this area. Overall, crew conduct was professional and orderly:-however, the use of three-part communications during the observed scenario was not consistently reinforced as it has been during actual control room activitie (Section 05.1)
e' The licensee has effectively implemented its operating experience feedback program, as demonstrated by daily discussions in management meetings and resolution of pertinent plant issues through the corrective action program. (Section 07.1)
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Maintenance
. Eight apparent violations were identified concerning surveillance testing of the auxiliary building ventilation (VA) system. These .
apparent violations involved noricompliances with the requirements of TS 3.7.7: 10 CFR Part 50, Appendix B. Criteria XI and XVI: 10 CFR Part l
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I 50.71.e:' and TS 6.8.1.a. The Unit 2 A-train VA system surveillance test i failures did not reveal evidence that the system's ability to perform i its safety function was degraded. The licensee's identification of the March 16, 1998, test failure was a good observation. However, the licensee exhibited non-conservative decision-making concerning surveillance test failures, the implications for system operability, and
! TS action statement entr (Section M3.1)
Enaineerina
. Engineering human performance issues contributed to the apparent violations associated with auxiliary building ventilation system
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testing. Additionally, examples of failure to complete modification implementation warranted management attertio (Section E1.1)
Plant Succort l
. Radiation protection activities were performed adequately. No 4 violations or deviations were identifie (Section R1.1)
. Primary chemistry sampling activities were observed to be in compliance with procedures and proper controls were in place for protection from potential radiological and safety hazards. Acceatance criteria contained in procedures were consistent with Tec1nical Specification (Section R1.2)
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Report Details Summary of Plant Status Unit 1 operated at or near 100 percent power during the inspection peric Unit 2 operated at or near 100 percent power during the entire inspection l period, except on March 29, 1998, when reactor power was conservatively l reduced to 97~ percent to address an erroneous operator aid computer indication of reactor power (thermal best estimate) being greater than 100 percent. The bad indication was due to input from a failed feedwater flow instrument channel associated with the 2C steam generator. The instrument input was temporarily removed from the best estimate calculation and tha unit returned to 100 percent power on March 30, 199 Review of Vodated Final Safety Analysis Reoort (UFSAR) Commitments While performing inspections discussed in this report, the inspectors reviewed the applicable portions of the UFSAR that were related to the areas inspecte The inspectors identified a discrepancy between the UFSAR and the plant concerning the normal continuously filtered operating mode of the auxiliary building ventilation system (see Section M3.1). This discrepancy was characterized as an a) Otherwise, the UFSAR wording was consistent with the o) served parent plant violatio practices, procedures, and parameter I, Operations 01 Conduct of Operations 01.1 General Comments (71707)
The inspectors conducted frequent control room tours to verify proper staffing, operator attentiveness and communications, and adherence to approved procedures. The inspectors attended operations shift turnovers and site direction meetings to maintain awareness of overall plant status and operations. Operator logs were reviewed to verify operational safety and compliance with Technical Specifications (TS).
Instrumentation, computer indications, and safety system lineups were periodically reviewed, along with equipment removal and restoration records, to assess system availability. The TS Action Item Log books for both units were reviewed for potential entries into limiting
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conditions for operation (LCO) action statements. The inspectors conducted plant tours to observe material condition and housekeepin Problem Identification Process (PIP) reports were routinely reviewed to ensure that potential safety concerns and equipment problems were resolved. In general, plant operations were conducted wel .2 Ooerations Clearances - General Comments (71707)
The inspectors reviewed the following clearance during the inspection period:
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Tagout 28-248. Nuclear Service Water System Valve 2RN-236, placed March 17, 1998
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h The inspectors observed that the' clearance was properly prepared and ~
l- authorized, and that the tagged components were in the required
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. positions with the appropriate tags-in plac .3 'Onsite Followuo of Events - Annulus Ventilation System Inocerability Insoectfon Scoce-(71707/93702) The ins 3ectors reviewed the circumstances surrounding a reportable event i in whici.the Unit 2 containment annulus ventilation. system was determined to be inoperable for a period of five and one-half hours on March 12-13, 1998, due to a blocked-o)en annulus. ventilation boundary door, Upon discovery of the event, t1e licensee made a one-hour, non-emergency report to the NRC in accordance with 10 CFR 50.72(b)(1)(ii)(B)
on March 17, 199 The inspectors reviewed compensatory action program documents, modification paperwork, and discussed this event with plant personne Observations and Findinas-The licensee identified this event four days after its occurrence following a similar near-miss on the corresponding door for Unit 1 for which PIP report 0-C98-0956 had been generated. The Unit 2 event was documented in the same PIP. On March 12. licensee personnel were in the process of changing the security access control system for control 1 access door AX3930 (Unit 2 lower containment airlock enclosure door) in accordance with Nuclear Station Modification (NSM)'CN-50463. This
- modification replaced the previous security door access card reading i system with an improved magnetic card reading system and was-implemented !
for other vital area doors and protected area access portals as wel ;
The modification was implemented .for door AX3930 on. March 12-13, 1998, using work order number 97087733 01. This door is an integral part of l the annulus ventilation (VE) system boundary and is required to be closed during and following an accident in order for the VE system (in ;
conjunction with secondary containment) to perform its accident mitigation' functions as described in Section 9.4.9.1 of the UFSAR. The Unit 1 and 2 VE systems (two trains each) are required to be operable by i TS 3.6.1.8 with the units in Modes 1 through 4. One train for each unit -
'is allowed to be ino)erable for periods of up to seven days before the i unit must commence slutdown to Mode This TS does not recognize the '
inoperability of both trains simultaneously while in Modes 1 through 4:
l thus. unit shutdown would be required within the seven-hour time frame established in TS 3. On March 12, 1998, one of the workers realized that the card reader
!- modification could not be performed on door AX393D without securing it
'in the open position, due to physical restrictions in the work area. As a result, workers obtained a generic compensatory action form from the '
work control center (WCC) and the door key was' issued from the WCC to a radiation protection worker providing job coverage. The workers then proceeded to the job location and tied the door open with a rope attached to a nearby handrail, The door was secured open for L
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approximately five and one-half hou~r s. According~to licen~see' personnel, workers were at the door for the duration that it was o)ened. Although the workers were unaware of any im)act on operability. laving the door secured open greater than four incles resulted in both trains of the containment VE system being inoperable, resulting in the unit being in TS 3. The licensee'had previously established a com
~for doors. hatches, and manways to allow non pensatory routine work toaction occur program which would require them to be opened for periods exceeding the time allotted for routine egress and ingress activities. The compensatory action program had been revamped years ago due to a similar 1990 situation in which the VE system was inoperable for ten hours due to a blocked open Unit 1 upper annulus doo Compensatory action forms were supported by written safety evaluations (with unreviewed safety question determinations) in accordance with 10 CFR 50.59. Doors could be opened for purposes of performing work as long as compensatory actions with accompanying safety evaluations supported it. The compensatory action forms were divided.into generic and specific types: with generic types addressing fire, tornado, and i security protection requirements. The specific forms addressed certain )
prerequisites and personnel responsibilities required for affected TS 2 systems to be considered operable. All compensatory action forms (generic and specific) were contained in a compensatory action manual ,
located in the WC The generic compensatory action form obtained by the workers on March 12, 1998, addressed actions to take for fire security, and tornado protection; and directed personnel to shut the door u)on hearing the announcement of- a safety injection or reactor trip. iowever, the generic form also contained an initial condition that it could only be
.used in conjunction with a specific compensatory action form while the !
unit was in Modes 1 through 4. A referenced note (number 4) in the I compensatory action guidelines restated this prerequisite. The
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accompanying 10 CFR 50.59 safety evaluation for the generic (fir I tornado, security) compensatory actions stated that the margin of safety to any TS will not be reduced because no VE pressure doors.may be opened under these compensatory actions. Operations or WCC personnel did not
observe or follow the initial conditions or note 4 and authorized the work on March 12 under just the generic compensatory action Following the event, the licensee discovered that the specific compensatory action form referenced on the generic form and in note 4 had been discontinued more than a year earlier. Discussions with licensee personnel indicated that the specific form was discontinued due to concerns that the amount of radiation dose potentially received by the worker performing door closure during an accident exceeded allowable or analyzed amount In the front of the compensatory action manual was an index which indicated for all affected doors whether or not generic or specific (or
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both)~ compensatory actions' applied'.
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For door'AX393D. the 'iddex indicated that both a generic and specific form applied. The index had not been updated to reflect the deleted status of the specific compensatory action for Discussions with cognizant personnel indicated that the index was not updated because there were intentions to provide an updated specific compensatory action with a revised 10 CFR 50.59 safety evaluation to support it. The inspectors concluded that although the.index was not up-to-date, the reference to the specific I compensatory action, along with the statements in the generic form and '
the guideline note 4. provided ample opportunity for personnel to >
further scrutinize performing the work under just the generic compensatory actio Safetv/Reaulatory Imoact Because the licensee identified this event four days after its occurrence (and after it had already been corrected with the door's closure), only a past-operability review was performed in accordance with Nuclear System Directive 203. Operability. The licensee determined that the annulus ventilation system could not have )erformed its intended function by establishing and maintaining t1e required negative-pressure of 0.5 inch' water gauge within 60 seconds of a signal as required by TS 3.6.1.8 (and described in the UFSAR) while the door was secured open greater than four inches. However, the licensee concluded l that the safety significance was reduced by the fact ~ that even with the door open, the system would have produced enough vacuum such that airflow would have been into the annulus. Additionally, the generic compensatory actions issued on March 12, 1998, directed ~ personnel to shut the' door upon hearing the announcement of a safety injection signa Due to a number'of recent PIPS regarding compensatory action program implementation. plant managenient identified just prior to the event that more attention was warranted in this area. A two-week Safety Review Group assessment was initiated just days before the event and provided several. insightful findings and recommendations to licensee management for improving the program and its implementation. The Safety Review Group assessment and associated corrective actions had not been finalized when the event happene *
The licensee's root cause determination concluded that the event was caused by an inadecuate process for determining what compensatory-actions were needec in order to perform work on the door. The inspectors noted that this root cause statement did not take into account the fact that there were three clear statements in the compensatory action manual essentially archibiting the work under the i
generic compensatory action form and tlat human performance errors were more likely the key contributors to the event.
, The licensee has' initiated several corrective actions as a result of this event. The inspectors will follow the corrective actions and
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address:the regulatory significance"of the ' event while rev'ie~ wing
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associated LER 50-414/98-0 ) Conclusions I The Unit 2 annulus ventilation system was inoperable for five and one- i half hoors on March 12-13, 1998, due to personnel error during the i l
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issuance and implementation of a compensatory action prior to performing
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work on a lower containment airlock access door. The licensee's root cause attributed the event to an inadequate process for determining what compensatory actions.were required to perform work on the door. The fact that three clear statements in the compensatory action manual essentially prohibited work on the door under the given circumstances was not developed in the licensee's root cause analysis. The licensee, however, had performed a good assessment of the compensatory action
. program which provided insightful findings and has initiated corrective actions to improve the overall program and its implementation. The event was reported to the NRC in accordance with regulatory requirement . Operator Knowledge and Performance 0 Inadvertent Ooenino of Inservice Seal In.iection Filter 2B Vent Valve Insoection Scooe (71707)
On March 30. 1998, while attempting to swap reactor coolant pump (RCP)
seal injection filters on Unit 2, o>erators unknowingly opened the vent' ,
valve on the inservice filter, whic1 resulted in a momentarily low seal '
injection flow to the reactor coolant pumps. The inspectors reviewed PIP 2-C98-1165, operator' statements, station operating procedures, and applicable system drawings. The inspectors also discussed this incident with station management and control room personne Observations and Findinos ,
On March 30, 1998, during operations shift turnover, RCP seal injection filter 2A, which was thought to be in service, was identified to th oncoming shift as requiring monitoring for increasing differential pressure. The differential pressure at shift turnover was indicated as approximately 35 pounds per square inch differential (psid). Shortly
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after shift turnover, the " Seal Injection Filter 'A' Hi D/P" annunciator
! was received in the control room. The annunciator setpoint was 40 psi A pre-job brief was conducted and the Unit 2 control room supervisor I_
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directed non-licensed operators to place the standby seal injection filter, thought to be filter 28. in service per. OP/2/A/6200/001.
E Chemical & Volume Control System Revision 81, Enclosure 4.5.
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Removing / Returning Seal Water Injection Filter 2A From/To Servic While attempting to place the standby filter in service, the o)erators
, performed step 2.1.2 by opening the vent valve on filter 2B, w11ch was
{ actually the filter already in service. The " Reactor Coolant Pump Seal
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Injection Lo' Flow" alarm was~ received-in the control room which was ' '
normal for the evolution. However, the " Reactor Coolant Pump Seal Injection Flow Low" computer alarms for all four RCPs also came in, which was not expected. Upon realizing the mishap, operators immediately closed the 2B filter vent valve. The expropriate filter changeout was accomplished successfully later in the ^if A subsequent review by licensee personnel revealed that a completed valve lineup enclosure for placing seal injection filter 2B in service had not been filed in the control copy file (located in the control room) after its completion two weeks earlier on March 17, 1998. The file contained the previously completed enclosure from March 2,1998, which had placed the 2A filter in service. This error misled the operators into believing that filter 2A was still in service on March 30, 1998. The licensee s initial planned corrective actions were focused on enhancing operating procedure OP/2/A/6200/001 to require operators to verify by three different methods which filter was in service prior to performing the swap activities.
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The inspectors questioned the validity of the A-train high differential pressure annunciator alarming while the 2B filter was in service. By
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reviewing the system drawings and observing control room instrumentation, the inspectors learned that the location of the piping taps for the 2A and 2B seal injection filter differential pressure instruments rendered the indications common to both filters, thus instruments 2NVPT5640 and 2NVPT6340 (which fed the annunciators) would indicate the same differential 3ressure regardless of which filter was in service. Discussions with t1e OSM revealed that instrument drift or a shift in calibration between the two instruments would likely determine which annunciator, " Seal Injection Filter A Hi D/P" ()anel 2AD-7, window B/4) or " Seal Injection Filter B Hi D/P" (window E/4), is I
received first. The inspector was concerned that this problem potentially allowed control room operators to receive erroneous and misleading annunciator alarms, as was the case on March 30, 1998. In addition, the alarm response procedure OP/2B/6100/010H, Annunciator Response for Panel 2AD-7, immediate actions for annunciators B/4 and E/4, directed control room operators to verify the alarm condition by using the applicable differential pressure indication. That action would not necessarily direct them to the correct filter. The inspectors concluded.that these factors were key contributors to the problem on
March 30, 1998. The fact that the incorrect valve lineup enclosure was filed in the control room was a minor contributor that exposed the more significant issue As mentioned above, station management, in its efforts to 3revent recurrence of this event, initially focused on enhancing t1e filter swa)
! procedure to incorporate the use of diverse methods in determining whici
- filter was-in service prior to change-out. The inspectors concluded that this merely compensated for (instead of correcting) the root of the problem (flawed instrumentation / annunciator design). The ins)ectors l discussed this issue further with plant management and re-emplasized
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that control room operators do not have a reliable method for
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~ determining which seal -injection-filter is in service due to the current instrumentation design flaw. The inspectors also considered this issue to be an operator work-around that had not been previously tracked by the licensee. The inspectors were told that because this had been dealt with for years, it had not been previously viewed as an operator work-aroun )erations personnel, after deliberating further on this issue, informed t1e inspectors that the indication / annunciator problem was to be included in the operator work-around progra Conclusions An administrative error lead operators to unknowingly vent an inservice reactor coolant pump seal injection filter, resulting in momentarily loa seal injection flow to all four RCPs. The error highlighted a long- l standing design flaw associated with RCP seal injection filter i differential pressure indication and annunciation in the control roo Licensee personnel had previously worked around the indication l deficiency by relying on administrative means to determine which filter i was in service, but had not included this issue in the o)erator work around program, nor had measures been taken to correct t1e instrumentation design fla Operator Training and Qualification 05.1 Evaluated Active Simulator Exam Observations l Insoection Scooe (71707)
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The inspectors observed an Active Simulator Exam (ASE) conducted as part of operator licensing requalification training. This inspection was conducted to observe simulator training for licensed senior and reactor operators and verify consistencies between the simulated and actual :
control room environments. This inspection included 3rior review of the I evaluated scenario and various Operations Management 3rocedure Observations and Findinas The ASE was of sufficient difficulty and adequately challenged all crew
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members. Several malfunctions were programmed into the scenario to test the crews ability to recognize and deal with degrading plant condition Although the number of plant failures were sufficient, the secuence and timing of events in the scenario did not allow for the use anc interpretation of TS or for the performance of related actions if required. Licensee management indicated that some scenarios are fast-paced by design and do not provide opportunities for TS action implementation. They indicated that other scenarios have been used to challenge operators on TS usage in the pas Communication used throughout the exam was clear, concise, and generally in accordance with Operations Management Procedure 1-11. Operations ,
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! 8 Communication Standards. Revision 1. -The inspector noted: however. -that'
three-part communications, as described in DMP 1-11, were not used consistently in all operator actions and crew repeat-backs during )
i procedure transitioning could be improved. Although this discrepancy was noted during the scenario, the inspectors have not observed any deficiencies in this area during actual control room activities in the plant. ~ k
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The general conduct of simulator operations was professional and orderly. Good command and control was exhibited by the operations shift manager (OSM) on duty. Crew briefings conducted by the OSM were timely and thorough, and they facilitated crew discussions on expected plant response while working through emergency procedures. The inspector noted. however, that when the Alert declaration was made, degrading i plant conditions that would potentially require upgrading the Alert I classification to a Site Area Emergency classification were not !
communicated to the cre l
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The inspector identified that EP/1/A/5000/F-0. Critical Safety Function j Status Trees. Retype 3 was not being implemented properl Specifically, step C.1.b., used to monitor critical safety functions, directed operators to " Record status upon initial review of each function and any subsequent changes in the status of any function on the l following table." The table provided was not used during the AS Critical safety function status trees were monitored by the Shift
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j Technical Advisor (STA), the results of which were recorded on notebook 4 paper. The inspectors were concerned that, during an actual event, this i inappropriate procedure implementation could lead to confusion during l the transition between critical safety function res]onse procedures and '
other emergency operating procedures. This table )y its incorporation in the procedure, served as a permanent record of critical safety ;
function status and a source of information for post-accident i evaluatio l The inspector observed the debriefing conducted by the three training department ASE evaluators and the simulator booth operator With the exception of the aforementioned procedural implementation problem, the
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evaluators * comments on crew performance were accurate, relevant and .
comprehensiv c. Conclusions i
The observed active simulator exam was challenging and required l l
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operators to demonstrate their abilities in recognizing and handling degraded plant conditions. Although the observed scenario did not i l challenge operators on the use of Technical Specifications. licensee j management indicated that other scenarios have involved and will *
continue to involve performance measures in this area. Overall, crew conduct was professional and orderly; however, the use of three-part !
communications during the observed scenario was not consistently !
reinforced as it has been during actual control room activities. One l l l l
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- procedure ~ implementation problem was' noted concerning the STA not using a table provided for documenting critical safety function statu Quality Assurance in Operations 07.1 General Comments (71707. 40500) ,
The ins]ectors observed activities during site direction meetings and noted tlat operating experience feedback items were discussed on a daily basis. Technical, programmatic, or human performance issues arising from different plants within the Duke system or )lants throughout the industry, were discussed in detail to determine t1eir applicability to the Catawba station. Pertinent issues were incorporated into the licensee's corrective action program via PIP reports. The inspectors have seen tangible results of these efforts including the licensee's investigation into technical issues related to the material condition of control power fuses for the emergency diesel generators. TS compliance issues, and performance issues related to the ice condenser system. The inspectors concluded that the licensee effectively implemented its operating experience feedback progra Miscellaneous Operations Issues (92901)
0 (Closed) VIO 50-413/90-19-01: Failure to Perform Adequate 10 CFR 50.59 Review Leading to VE Inoperability This violation was issued in 1990 after plant personnel blocked open a Unit 1 upper annulus door without performing a 10 CFR 50.59 safety evaluation, resulting in both trains of the Unit 1 containment annulus ventilation (VE) system being ino3erable for approximately 10 hour1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> Due to an administrative error, t1e NRC staff never reviewed this violation for closure, and never documented its closure in a subsequent inspection report. Licensee personnel brought the error to the inspectors' attention during this period while reviewing a recent similar Unit 2 VE system inoperability event discussed in section 0 of this report. The 1990 event and the one discussed in section 0 both centered around the inappropriate use of compensatory actions while performing work affecting annulus ventilation boundary doors. Following the 1990 violation, the licensee committed to providing better
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procedural guidance on the areas in which compensatory actions can be used and on the methods to be used in conducting 10 CFR 50.59 safety evaluations.
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Due to its age. the 1990 violation is administrative 1y closed and any .
common themes present between it and the recent event will be reviewed i
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and tracked by the NRC under LER 50-414/98-01 (due to be submitted after the inspection period ended).
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II, Maintenance M1 Conduct of Maintenance M1.1 General Comments on the Conduct of Surveillance Testino (61726)
The inspectors observed portions of the following maintenance activities and surveillance tests:
. IP/0/A/3850/009. Revision 37, Inspection and Maintenance Procedure for Motor Control Center Breakers (auxiliary contact replacement for 2KC-51A)
. IP/0/A/3820/007. Revision 28. Troubleshooting and Maintenance of Rotork Actuators (oil leak at actuator handwheel of 2KC-51A)
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IP/0/A/3820/004, Revision 300, Operating Checkout of Limitorque and Rotork Valve Actuators (preventive maintenance on 2KC-51A actuator)
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IP/1/A/3222/076A Revision 69. Calibration Procedure for 6T/Tm Protection Channel I
. IP/1/A/3176/001A, Approved September 8, 1995. Procedure for Containment Hydrogen Monitor System (VY) Analog Channel Operational Test
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PT/2/A/4200/027. Revision 29. NW Valve Inservice Test (0U).
Enclosure 13.7. 2NW-61B Valve Inservice Test
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PT/0/A/4400/022B, Revision 51, Nuclear Service Water Pump Train B Performance Test In general, the above-listed maintenance and surveillance activities were performed well with proper adherence to procedural compliance, equipment calibration, and radiation protection requirement M3 Maintenance Procedures and Documentation
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M3.1 Auxiliary Buildina Ventilation Surveillance Test Failure a. Insoection Scooe (61726)
On March 25, 1998. the Unit 2 A-train Auxiliary Building Ventilation (VA) System Filter Unit (ABFU) failed to meet acceptance criteria during performance of a TS surveillance test. The licensee declared the system inoperable and initiated corrective actions to correct the low flow condition. Maintenance was performed to remove unnecessary components suspected of blocking air flow. Following maintenance, the surveillance test was successfully completed late on March 25 and the system was declared operable. The licensee determined that the system had been inoperable for nine days, thereby exceeding TS LCO action requirement ____-__ _ _ ______ _ _ _ _
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The inspectors reviewed the applicable TS, UFSAR sections, and American NationaT Standards Institute (ANSI) Standard N510-1980 (which is referenced in the TS, the-TS basis and the UFSAR as the procedural guide for surveillance testing). The inspectors also reviewed: PIP reports that documented Unit 2 A-train VA system low flow conditions-identified on February 9 1998. March 16,1998. and March 25. 1998: the associated surveillance procedures: and control room logs. The inspectors discussed the test failure with engineering and operations test personnel, Observations and Findinas ,
System Description ,
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The VA system serves both a nonsafety and a safety-related function, including an Engineered Safety Features (ESF) function during accident conditions. During normal plant operation, the system services non-safety and safety-related loads with the HEPA and carbon filters !
continuously in service. During accident conditions. the system is designed to draw 5,640 cubic feet per minute (cfm) only from the i emergency core cooling system (ECCS) aump rooms (the safety-related i portion of the system) and maintain t1e rooms at a negative pressure to minimize radiation dose associated with component leakage in those rooms. A safety injection signal will cause dampers to isolate nonsafety-related )ortions of the system from the safety-related
. portions so that t1e system can fulfill this safety functio l Backaround Information: A-Train low Flow Condition Identified Durina B-Train Test-
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-On February 9. 1998, the licensee performed surveillance test PT/0/A/4450/01C. Auxiliary Building Filtered Exhaust Filter Train Performance Test, approved May 5. 1986, on the Unit 2 B-train VA syste The test implemented 18-month TS surveillance requirements 4.7.7. .7.7.b.3. 4.7.7.e and 4.7.7.f. Step 11.1 of the procedure defined a pressure drop across the filter unit of less than 7.9 inches water gauge while operating the system at the designed flow rate of greater than or equal to 27,000 cfm and less than or equal to 32.000 cfm as acceptance criteria for Section 12.2.1 of the test, which governs airflow capacity
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tests of Unit 2 A and B-train ABFUs. Measured airflow for Unit 2 B-train had met the acce)tance criteria at 30,272 cfm: however, the technicians performing tie test had noted that 2 A-train VA system flow, j which had been quantified to calculate flow for the Unit 2 B-train surveillance test, was low at 26.771 cfm. Although the Unit 2 B-train surveillance had been successfully completed, the Engineering l organization was notified of the Unit 2 A-train low flow condition, and L : station PIP 2-C98-0514 was generated to document the issue.
l An operabi.lity evaluation was completed to demonstrate that the Unit 2 A-train Auxiliary Building Filtered Exhaust System was operable. The operability evaluation, documented in PIP 2-C98-0514.' indicated that one
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of the normal-VA system ventilation supply air' handling units ~(ABRSU-2) ~
to the auxiliary service building (radwaste facility) had been out of service during~the test. According to the operability evaluatio ABRSU-2 could normally supply 9.545 cfm of outside air to each Unit 2 VA l system filtered exhaust train. The basis of the determination that the )
Unit 2 A-train of VA was operable was the assumption that, with ABRSU-2 i
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in service -the flow capacity. acceptance criterion would have been me No test was performed at that time to confirm this assumption. Furthe the licensee identified that clogged flow-straighteners on the system needed to be removed, as. documented in PIP report 2-C98-051 The inspectors discussed the test results with engineering personnel and reviewed design basis and UFSAR documentation. The inspectors L considered that because the train was not being tested directly and was not due to be tested, the licensee's approach was consistent with NRC guidelines for operability determination .A-Train VA Test and Subseouent Inocerability The following paragraphs document several human performance deficiencies occurring between March.16 through 25, 1998, and the inappropriate actions and decisions made by station management associated with the March 16, 1998. Unit 2 A-train surveillance test failure. Several non-compliances with the licensee's test procedures, administrative ,
programs, and regulatory requirements ultimately caused the Unit 2 i A-train of VA to be inoperable in excess of TS limits. Long-standing '
procedural deficiencies that were identified stemmed from inadequate test control for this system. Because of the significance of these issues in the aggregrate, the non-compliances were all characterized as apparent violations and are discussed individually in the following paragraph On March 16. 1998, the licensee performed a scheduled surveillance test on the Unit 2 A-train ABFU using the same 3rocedure as previously referenced for B-train testing and with AB1SU-2 in service. Measured airflow was 26.129 cfm. which was below the airflow capacity test acceptance criterion of 30.000 cfm +/-10%. Step 12.2.1.4.1 of the procedure was initialed by the test technician that the acceptance-criteria had not been met. Ste 12.2.1.4.2 directed the test technician
.to notify the Shift Supervisor performance Engineer and the Licensing Engineer and have the system (equipment) declared ino)erable in
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accordance with its LC0 in TS. Instead, the test tec1nician notified the Work Control Center (WCC) SR0 that the test acceptance criteria had not been met and that the system was inoperable. The Operations Shift Manager (OSM) was not formally notified of the test failure and low flow condition, although he was cognizant of the issue. The system was not declared inoperable in accordance with the surveillance procedure. As a result of this initial error, the system was inoperable for over nine days, and the TS LC0 3.7.7 action statements were not met. This failure to have the. system declared inoperable in accordance with applicable
)rocedures is characterized as Apparent Violation (EEI) 50-414/98-03-01:
railure-to Follow Surveillance Test Procedur _ _ _ - _ _ _ _ _ _ _
Nuclear System Directive-(NSD) 203. Operability. Revision 10.~ Appendix A. 203. Operability Policy for Previously Identified Items, defines the licensee's policy governing failed TS surveillance tests as follows:
"Upon initial discovery of a failed surveillance, the affected system, subsystem, train, component or device shall be declared inoperable and the applicable TS action statement entered." Despite this administrative requirement. the Unit 2 A-train VA system was not declared inoperable. The failure to declare the Unit 2 A-train VA system inoperable following a failure of system performance to meet TS surveillance test acceptance criteria was the first of two non-compliances with NSD 203 and is characterized as Example 1 of Apparent Violation (EEI) 50-414/98-03-02: Failure to Follow Administrative Procedure Governing Operabilit On March 16. 1998, the test technician. his supervisor, the system engineer, and the WCC SRO discussed the test failure. The system engineer 3rovided a verbal statement that the Unit 2 A-train VA system was opera]le. The basis of this operability statement was that the safety function of the system, to draw 6.540 cfm from the ECCS pump rooms and maintain them at a negative pressure to minimize radiation dose associated with ECCS aump leakage could still be performed. The inspectors noted that the ] asis for the operability determir.: tion associated with the low flow condition identified on February 9.1998, had been invalidated by the March 16 test results (with AHU ABRSU-2 o)erating). The inspectors were not aware of any attempt to reconcile t1e March 16. 1998, test failure with the basis of the operability determination associated with the low flow condition that had been identified on February 9.199 The inspectors noted that a formal, documented operability notification was not provided for the March 16, 1998, test failure in accordance with NSD 203. Operability. Revision 10. Section 203.9.1 General Requirements, which states " Notification to Operations (OSM) shall be accomplished by com)1etion of Appendix E. 203 Operability Notification Form, as described ]y this directive." During the root cause investigation into tnis event, licensee personnel contended that no formally documented operability form was required since one had not been requested and the system in question was not considered inoperable by operations at the time of the March 16, 1998, failure. The inspectors
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considered that the results of the test, which were documented as a failure in the surveillance procedure, alone constituted a requirement to provide written documentation of the system's operability. The failure to provide a formally documented operability notification to the OSM following a failure of the Unit 2 A-train VA system performance to meet TS surveillance test acceptance criteria is charac.te-ized as Example 2 of Apparent Violation (EEI) 50-414/98-03-02: Failure to Follow Administrative Procedure Governing Operabilit Station PIP 2-C98-1002.-generated on March 18, 1998 (two days after the test failure). was screened for significance by the Safety Review Group on Marcil 19. and was assigned to Engineering for evaluation. However, the Engineering review did not begin until March 23. The inspectors
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questioned the timeliness with which the issue received a formal engineering review, and station management responded that the PIP was generated two days after the test failure because the person that initiated the PIP on March 18 did not work on March 17. In addition, the PIP was screened on a Thursday, and Duke employees do not typically work Friday through Sunday. Nonetheless, station management acknowledged that performance in this area did not meet timeliness expectation '
On March 23. engineering personnel began to question the basis of the conclusion that the system was operable. since the TS surveillance acceptance criterion of 30.000 cfm +/-10% clearly had not been met and, thereby nullified any other basis of system operability. To demonstrate operability, a second attem)t to meet the TS surveillance acceptance criterion was planned. The Jnit 2 A-train VA system test was initiated again late on March 24, 1998. The spent fuel building ventilation (VF) system was removed from service to provide additional assurance that the minimum flow requirements for the test could be me However. ABRSU-2 would not start and was not available for the tes Airflow was measured at 26.946 cfm without ABR$U-2 running. Following corrective maintenance on ABRSU-2, a second attempt to run the test ,
early on March 25 yielded a test result of 26.889 cfm. A misaligned backdraft damper was identified and correctly ali ned. A third attempt to meet test acceptance criteria revealed an airf.ow of 26.969 cfm. The Unit 2 A-train VA system was declared inoperable. The inspectors noted i that even though the system's operability was questioned on March 23. it was not declared inoperable until after the last test failure on March 2 The inspectors noted that NSD 203. Operability. Revision 10. A)pendix . Generic Letter 91-18 NRC Inspection Manual Part 9900: Tec1nical i Guidance. Section H.2.6.5. Surveillance and Operability Testing in l Safety Configuration. states that repetitive testing to achieve I acceptable test results without identifying the root cause or correction of any problem in a previous test is not acceptable as a means to establish or verify operability. The repetitive attempts to meet surveillance test acceptance criteria is characterized as Example 3 of i Apparent Violation (EEI) 50-414/98 03-02: Failure to Follow i Administrative Procedure Governing Operability. The licensee stated !
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that it performed the repetitive tests on March 24 and 25 due to the i failures of AHU ABRSU-2 and its associated backdraft damper to operate during the first two attempts. However, the inspectors concluded that if these first two attempts at meeting the acceptance criteria had been i satisfactory, the procedure would have directed personnel to declare the i test successful and the system operable, regardless of the caerating l status of the two components in Furthermore, neitler of these '
componentscausedthesystentohuestio ail to meet surveillance test acceptance criteria. Therefore, the inspectors concluded that the tests i were repeated to achieve acceptable result ~
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Similarly. NSD 408. Testing. Revision 5. Section 408.7.2.2. Invalid l Test states that failure to meet acceptance criteria is by itself not a i
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- valid reason to consider the'-test ' invalid and're-perform a procedure '
section. Based on discussions with licensee personnel, the inspectors concluded that if the airflow acceptance criteria had been met, the surveillance tests would have been considered valid. Therefore, the multiale attempts to meet the airflow capacity test acceptance criteria are characterized as Apparent Violation (EEI) 50-414/98-03-03: Failure
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to Follow Administrative Procedure Governing Testin TS LC0 Implications The inspectors were concerned that the licensee had opportunities on i March 23, 1998, to prevent the equipment inoperability from exceeding l l the TS seven-day limit and inquired as to why the Unit 2 A-train of VA 1
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was not considered inoperable before the March 24-25, 1998, test '
failures. The 1-icensee indicated that the March 16, 1998, test was considered an invalid test during discussions between plant managemen ;
operations, engineering, and regulatory compliance personnel on March '
24, 1998, based on the operating status of the VF system at the time of the test. The inspectors did not agree with the licensee's conclusion that the March 16 test was an invalid test for several reasons: (1) the test procedure did not specify a particular system alignment as an initial condition for the conduct of the test: (2) involvement of engineering to provide an operability determination. indicated that the test was considered valid at the time of the failure: (3) NSD 40 Testing. Revision 5. Section 408.7.2.2. Invalid Test states that
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failure to meet acceptance criteria is by itself not a valid reason to consider the test invalid and re-perform a procedure section: and (4)
step 12.2.1.4.2 directed the test technician to have the system (equipment) declared inoperable in accordance with its LCO in TS if the airflow capacity acceptance criterion could not be met. In other words, the test procedure provided the airflow value of 30.000 cfm +/-10% as a basis for operability, not as a criterion for differentiating valid tests from invalid test The inspectors concluded that the licensee's decision to consider the 1 l
Unit 2 A-train VA system inoperable beginning March 25. 1998 (instead of l March 16. 1998). was in error. The licensee stated that March 25, 1998, was considered the time of discovery of the ino)erability of the VA train because only the last test performed on tlat date was considered valid. The inspectors concluded that, because the licensee recognized
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on March 24, 1998, the operability evaluation for the March 16. 1998.
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test failure was flawed, a more reasonable time of discovery would have been March 24. The inspectors considered that March 16. 1998, was the actual time of discovery because the low flow condition was revealed and {
acknowledged by the licensee on that dat ,
Technical Specification 3.7.7. Auxiliary Building Filtered Exhaust System. states that with one train of the VA system inoperable, restore the inoperable-train to operable status within 7 days or be in at least hot standby within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in cold shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. Because the licensee did not declare the Unit 2 A-train VA system inoperable on March 16 and take timely corrective <
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- action to correct a degraded flow condition the' system was inoperable'
for nina days, and the action required by T3 3.7.7 was not performe The inspectors concluded that the 15 3.7.7 action requirement to be in Hot Standby had expired as of March 25. In addition, when the Unit 2 A-train VA system was declared inoperable on March 25. 1998. station management contended that the LCO action statement began at that time and not'on March 16,11998. because the earlier test was considered invalid. The licensee did not re-characterize the March 16, 1998, test as a valid failure and consider the Unit 2 A-train VA system inoperable since that time. As a result, the licensee did not com)1y with associated TS action requirements on March 25, 1998. T11s failure to comply with actions associated with TS 3.7.7 is characterized as Apparent Violation (EEI) 50-414/98-03-04: Failure to Comply with Actions Required by TS 3.7.7 with One Train of the VA System Inoperable for-Longer than Seven Day Root Cause of Flow' Degradation Station PIP 2-C98-1002 was initiated on March 18 (two days following the test failure) to document the Unit 2 A-train VA system low flow tes result. The information in the PIP indicated that an immediate corrective action to address the Unit 2 A-train VA system low flow condition was to eliminate flow blockage within ductwork to increase VA system flows on Unit 2. The inspector determined that the engineering personnel involved in the operability evaluation (on March 16)
considered air flow straighteners in the system the root cause for the
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I previous low flow conditions. An immediate corrective action was l identified in the PIP to perform minor modification CNCE-7901 to correct l the low flow conditio )
Minor modifications (MM) CNCE-7900 (Unit 1) and CNCE-7901 (Unit 2) had been implemented in 1996 to correct a previously identified trend in degrading flow conditions of the VA system trains. The modifications involved the removal of unnecessary air flow straighteners in the system ductwork. The flow straighteners had been provided in proximity to flow instruments to establish a uniform air flow. This provided a means to ;
reliably measure and quantify air flow in the ductwork immediately downstream of elbow Flow gauges had been removed prior to 1996, and air flow measurements have been obtained by an alternative means since that time. The air flow straighteners were no longer performing any
function, and had been collecting dust and clogging over time.
j- In 1996, seven straighteners had been removed from portions of the ductwork that were shared between the two units. Six had been removed from Unit 1 VA system [ including one (the only) flow straightener in each of the safety-related trains of the system]. Six had been
~ identified for removal from Unit 2 VA system, but only three were actually removed in 1996 (including those in the A and B train safety-related . portions- of the system). The licensee had recently discovered that the other three straighteners had not been identified in the implementing work orders and had not been removed.
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The~1996 Unit 2 modification referenced three work orders for removing the flow straighteners. Work orders 96067501 and 96067502 governed the removal of two air flow straighteners from the safety-related A and
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B-trains of the VA system, respectively. Work order 96041503 was initiated to remove four additdonal air flow straighteners from shared, non-safety-related portions of the VA system. However, only one of the four components was removed from the VA system ductwork. Rather than identify each com3onent to be removed, the work order stated. " Remove air flow monitor loneycomb straightening vanes per minor modification CNCE-7901. . to resolve system VA filtered exhaust low air flow concerns." The minor modification listed the affected flow straighteners for each uni The Catawba Nuclear Station Modification Manual' Revision 9. was in effect at the time the modification was closed. Section 5.6.2. state " Prior to returning the MM Work Orders to the Operational Control Group for Return-To-Service, the Implementation Accountable or MM Originator shall verify that all activities as described by the MM have been implemented in the field or a Variation Notice written to revise the MM's scope accordingly." The inspector noted that the Minor Modification Post-Implementation Notice indicated that the modification was completed on December 23, 1996. The inspector concluded that adequate instructions to remove the straighteners were provided at the time and that, based on the existence of the remaining flow straighteners as of March 1998, the licensee failed to verify that the modification had been fully implemented in the field. The failure to verify that all activities as described in the 1996 MM had been implemented is characterized as Apparent Violation (EEI)
50-414/98-03-05: Failure to Verify Full Modification Implementation in Accordance with the Modification Manual. The remaining three air flow straighteners were subsequently removed on March 25, 1998, as a corrective action following the three test failures earlier that da Untimely Corrective Actions The inspectors concluded that the licensee was cognizant of the root cause of the low flow condition (clogged air flow straighteners);
however, inaction following the February 9.1998, identification of the Unit 2 A-train VA system low flow condition, and inaction following the
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failure of the Unit 2 A-train VA system to meet acceptance criteria during the performance of a scheduled surveillance test on March 1 , constituted a failure to take immediate corrective action to correct a known low flow condition. According to 10 CFR Part 5 Appendix B. Criterion XVI. measures shall be established to ensure that conditions adverse to cuality, such as failures and nonconformances, are promptly identified anc corrected. The failure to take timely corrective action to correct the root cause of the low flow conditions is characterized as Apparent Violation (EEI) 50-414/98-03-06: Failure to Take Timely Corrective Actions for Degraded Flow Conditions that Affected Unit 2 A-train Auxiliary Building Ventilation System Operabilit _ _ - _ - _ _ - _ - _ _ - _ - _ _ _ - _ - _ - _ - - - _ _ - _ - - _ _ _ - _ - _ _ _ _ _ - -- _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
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According to 10 CFR Part 50. A)pendix B. Criterion XI. Test Control, a test program shall be establis1ed to ensure that all testing required to
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satisfactorily in service. Test procedures shall include provisions for ensuring; in part.- that all prerequisites for the given test have been met and that the test is performec under suitable environmental conditions. Test results will be documented and evaluated to ensure that the test requirements have been satisfied. Similarly. ANSI-N510-1980. Testing of Nuclear Air Cleaning Systems. Section 4.2. Test Procedures, states that test procedures shall identify, among other things, the arrangement or clearances that have to be made prior to the ;
test and the prerequisites that have to be met. According to ANSI
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N510-1980. testing of air cleaning systems is an integral part of the licensee's Quality Assurance Program, and surveillance tests are used to monitor the condition of associated systems. The ANSI standard also i states that an airflow capacity test acceptance criterion shall be
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airflow within +/-10% of system design flow, thereby providing the basis for the TS acceptance criterion of 30.000 CFM +/-10%.
Despite the requirements of 10 CFR Part 50. Appendix B. Criterion XI.
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and ANSI N510-1980, the procedure, which had not changed since 1986 did l not establish a prerequisite, controlled system configuration or suitable environment (pertaining to the status or position of various L interfacing systems and equipment) for adequate performance of the tes As a result, a consistent, repeatable test methodology had not been established to ensure that system performance trends were mliable indicators of flow degradation. T1e failure to 3rovide adecrte test controls in the surveillance test procedure is cwxterizec as Apparent Violation (EEI) 50-414/98-03-07: Failure to Provide Adequate Test Controls in Accordance with 10 CFR Part 50. Appendix B. Criterion X and ANSI N510-198 Safety /Reculatory Significance The licensee identified the problems of March 16. 1998, after questioning the operability determination during an unrelated operability assessment the following week, Prior to bringing the March 16. 1998, test failure to the inspectors' attention, the licensee had
initiated a root cause investigation to evaluate various . issues associated with the conduct of the test (i.e.. adequacy of the test procedure, appropriateness of the o)erability determinations, and informal communication of the opera)ility status of the system). The final results were to be documented in PIP 2-C98-1077. The licensee r
also provided a past operability evaluation of the Unit 2 A-train VA system, which concluded that the train was technically inoperable from ( March 16 -25, 1998. but that the system's safety function, as defined in the UFSAR. was.not degraded during that period. This was primarily based on the fact that the remaining flow straighteners were located in the nonsafety-related portion of the system, which is isolated on a safety injection signal, and that flow in the safety-related portion was
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not affecte However ~the licensee concluded that this' issue was reportable per 10 CFR 50.73 and was planning to submit an LER at the end of the inspection perio *
The inspectors concluded that the licensee exhibited appropriate sensitivity to operability determinations during the independently initiated self-assessment that, on March 23, 1998. led them to discover the March 16. 1998, surveillance test failure. H wever, decisions made following the identification of the March 16, 1998. : surveillance test failure revealed a reluctance to comply with the required TS action statemen UFSAR Review The inspectors reviewed the UFSAR to assess the basis for the licensee's determination of safety significance. During this review, the inspeci. ors found that UFSAR Sections 7.6.12.1 and 7.3.1.1.1 stated that the VA system normally operated with the HEPA and carbon filters in bypas Radiation monitoring is provided upstream of filter trains an in the unit vent. - Upon a high upstream radiation indication, the UFSAR indicated that bypass dampers will automatically close and the filter
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train inlet dampers will automatically open to direct air flow through the filter trai The inspectors determined that the VA system's normal ,
alignment was in filter mode, contrary to the UFSAR description, and i that the system did not realign to that mode on a high radiatico signa Minor Modifications CNCE-61117 and CNCE-61118 were implemented for Units 1 1 and 2. respectively, in April 1996. The modifications involved a l change to the system's normal . alignment such that the filter units were l normally and continuously in service. However, the UFSAR had not been I updated to reflect the change. The inspectors reviewed the associated ;
safety evaluation for the modi'ication (done per 10 CFR 50.59) to !
determine if the licensee had edequately addressed the potential for an unreviewed safety question (US0). The licensee determined that the change did not involve a USQ and did not impact the system's ability to perform its safety function. The major impact of operating the system !
in continuous filter mode was that the filters received more operating time and. thus, were sampled and replaced more frecuently (based on the TS surveillance requirement to )erform methyl iodice penetration testing every 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of carbon adsor)er operation). The inspectors reviewed
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. previous TS surveillance test results associated with differential pressures across the filter trains and concluded that system performance met acceptance criteria. - The licensee indicated that it was considering a modification to return the system to normaR; operating in the bypass mode due to the additional maintenance burde The inspectors concluded that the 1996 modification had not been reflected in the UFSAR. Title 10 of CFR part 50.71.e states that each person licensed to operate a nuclear power reactor shall periodically update the FSAR to ensure that the information included in the FSAR contains the latest material developed. The updated FSAR shall be revised to include the. effects of, in part, all changes made in the
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facility or procedures as described in the FSAR: and all safety evaluations performed by the licensee in support of conclusions that changes did not involve an unreviewed safety question. The licensee indicated that the UFSAR changes incurred by the modification were included in the modification package, and that the associated 10 CFR 50.59 review was included in the annual update package, but that the l- updated' system description was never transmitted to the UFSAR update process. The failure to update the UFSAR is characterized as Apparent Violation (EEI) 50-414/98-03-08: Failure to Revise the UFSAR Description of Normal VA System Operatio Conclusions Eight apparent violations were identified concerning surveillance testing of the auxiliary building ventilation (VA) system. These apparent violations involved noncompliance with the requirements of TS 3.7.7: 10 CFR Part 50. Appendix B. Criteria XI and XVI: 10 CFR Part 50.71.e: and TS 6.8.1.a. The Unit 2 A-train VA system surveillance test failures did not reveal evidence that the system's ability to perform its safety function was degraded. The licensee's identification of the March 16. 1998, test failure was a good observation. However, the licensee exhibited non-conservative decision-making concerning surveillance test failures, the implications for system operability, and TS action statement entr III. Encineerin_g El Conduct of Engineering E1.1 General Comments (37551)
While engineering activities in general were noted to be performed adequately, examples of poor performance were tied to the apparent violations described in section M3.1 of this re) ort. Specifically, a two-year-old modification to remove flow straighteners from the nonsafety-related portions of the Unit 2 auxiliary building ventilation system was not completed until train A of the system failed a TS surveillance test on March 25. 1998. Additionally, operability
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evaluations to address previously-identified low system flow conditions were inadequate in that they did not sufficiently address TS acceptance criteri Another human performance issue surfaced during the inspection period while addressing a separate item involving a plastic cover that was found (without an approved modification) taped to a nonsafety-related ventilation register in the same system on March 2 . While the latter issue had no safety implications due to the com)onents involved, the number of human performance issues associated wit 1 it, including the failure to completely implement an earlier modification to install-sheet metal over the register, along with the
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other issues mentioned above, warranted increased management ~ attention ~
in the area of modification implementation.
l E8 Miscellaneous Engineering Issues (92903)
E (Ocen) URI 50-413.414/97-14-03: Noncompliance With 10 CFR 50, Appendix A, General Design Criterion 57. Closed System Isolation Valves
' The inspectors had performed Temporary Instruction 2515/136 - Operation Of Dual Function Containment Isolation Valves in November 1997. The purpose of this instruction was to determine if the licensee had
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procedures in place to remotely close containment isolation valves when required while a safety injection (SI) or a containment spray signal was
.present. At the time, licensee 3ersonnel indicated that, for certain valves, remote closure was possi]le only after the emergency diesel generator (EDG) load sequencer was reset (in addition to the normal action of resetting the ESF or SI signal). The URI was opened, in part, l to address the potential impact of this action on the accident !
mitigation functions of safety-related equipmen l After researching elementary diagrams and discussing this issue with l cognizant engineering personnel, the inspectors learned that resetting i the EDG load sequencer did not affect the dual function safety-related valves, and was not required for these valves to close to perform their containment isolation function. The previous information su) plied by 3 the licensee was in error. The new information alleviated t1e i inspectors * concern related to resetting the load sequence This unresolved item will remain open pending the resolution of a ,
noncompliance with 10 CFR 50, Appendix A. General Design Criterion 5 '
The licensee had submitted an exemption request to the NRC for this issue in September 199 IV. Plant Support-R1 _ Radiological Protection and Chemistry Controls R1,1 General Comments (71750)
From observations during routine plant tours, the inspectors noted that radiation protection activities were performed adequately. No violations or deviations were identifie R1.2 Primary System Samolina Activites - General Comments (71750)
- The inspectors observed primary. system sampling activities on March 25.
l 1998, performed in accordance with OP/2/A/6200/034, Revision 004, l
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Operating Procedure for Unit 2 NM Automation Sampling System, to verify proper procedure adherence and to ensure proper controls were in place for radiation protection and personnel safety. The inspectors reviewed Chemistry Management Procedure CMP 3.4.17.1, Primary Chemistry. Revision p 31 and verified that acceptance criteria met TS requirements. The
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- inspectors noted that the chemistry-technician requested approval from control room personnel prior to performing valve manipulations required for sampling, and kept control room personnel aware of associated valve status during sampling evolutions. The inspectors observed proper use of procedures. Techniques used during the sampling demonstrated the appropriate sensitivity to potential radiological and safety hazard No violations were identifie l l
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V. Manaaement Meetinas X1 Exit _Heeting. Summary i ..
.The inspector presented the inspection results to members of licensee management at the conclusion of the inspection on April 21, 1998. The licensee' acknowledged the findings presented. No proprietary information was identi fied.
l PARTIAL LIST OF PERSONS CONTACTED Licensee M. Birch. Safety Assurance' Manager -
M. Boyle. Radiation Protection Manager l R. Glover. Operations Superintendent P. Herran. Engineering Manager R. Jones.~ Station Manager M. Kitlan. Regulatory Compliance Manager G. Peterson. Catawba Site Vice-President R. Propst._ Chemistry Manager
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Commissioner N. Diaz L. Reyes Regional Administrator I
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-INSPECTION PROCEDURES USED
'IP 37551: Onsite Engineering IP 61726: Surveillance IP 62707: Maintenance Observation IP 71707: Plant Operation IP 71750: Plant Support-Activities-IP 92901: Followup - Operations IP 92903: Followu) - Engineering IP 93702: Onsite ;ollow-up of Events IP 40500: Effectiveness of Licensee Controls in Identifying, Resolving and Preventing Problems ITEMS OPENED. CLOSED, AND DISCUSSED Ooened 50-414/98-03-01 EEI Failure to Follow Surveillance Test Procedure (Section M3.1)
50-414/98-03-02 EEI Failure to Follow Administrative Procedure Governing Operability - Three Examples (Section M3.1)
50-414/98-03-03 EEI Failure to Follow Administrative Procedure Governing Testing (Section M3.1)
50-414/98-03-04 EEI Failure to Comply with Actions Required by TS 3.7.7 with One Train of the VA System Inoperable for More than Seven Days (Section M3.1)
50-414/98-03-05 EEI Failure to Verify Full Modification Implementation in Accordance with the Modification Manual (Section M3.1) ~
-50-414/98-03-06 EEI Failure to Take Timely Corrective Actions for Degraded Flow Conditions that Affected Unit 2 A-train Auxiliary Building
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Ventilation System Operability (Section M3.1)
50-414/98-03-07 EEI Failure to Provide Adequate Test Control in Accordance with 10 CFR Part 5 Appendix B, Criterion XI, and ANSI N510-1980 (Section M3.1)
'50-414/98-03-08 EEI Failure to Rbvise the UFSAR Description of Normal VA System Operation (Section M3.1)
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l i
!
!
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L 25-Closed'-
50-413/90-19-01~ VIO Failure to Perform Adequate 10 CFR 50.59 Review Leading to VE Inoperability i (Section 08.1)
Discussed-50-413.414/97-14-03 URI Noncompliance With 10 CFR 50. Appendix General Design Criterion 57. Closed System
,
Isolation Valves (Section E8.1)
LIST OF ACRONYMS USED'
ABFU -
Auxiliary Building Filter Unit
'AHU -
Air Handling Unit ASE --
Active Simulator Exam CFR -
-Code of Federal Regulations ECCS -
Emergency Core Cooling System l
'
EDG -
Emergency Diesel Generator-EEI -
Escalated Enforcement Item ESF -
Engineered Safety Feature FSAR - Final Safety Analysis Report o LC0 -
Limiting Condition for Operation LER~ -
Licensee Event Report NSD -
Nuclear System Directive NSM -
Nuclear Station Modification OMP -
Operations Management Procedure OSM -
.0perations Shift Manager PIP .
Problem Investigation Re] ort PSID -- Pounds per Squarc Inch Differential :
RCP -
Reactor Coolant Pump T -
. Average Reactor Coolant. System Temperature T5, -
Technical Specificatio UFSAR.- Updated Final Safety Analysis Report UR Unresolved Item US0 -
Unreviewed Safety Question Auxiliary Building Ventilation System
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VA- -
VF --
Spent Fuel Pool Ventilation System VIO -
Violation
!.: :WCC' -
Work Control Center p .WO -
Work Order
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t i