ML20203D888

Special Study, Operating Experience Feedback for Svc Water Sys Failures & Degradations 1986-1995

ML20203D888
Person / Time
Issue date:	02/28/1998
From:	Houghton J, Mohammed Shuaibi NRC OFFICE FOR ANALYSIS & EVALUATION OF OPERATIONAL DATA (AEOD)
To:
Shared Package
ML20203D883	List: ML20203D880 ML20203D884 ML20203D888
References
AEOD-S98-01, AEOD-S98-1, NUDOCS 9802260191
Download: ML20203D888 (82)

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I AEOD/S98-01'

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SPECIAL STUDY OPERATING EXPERIENCE FEEDBACK FROM SERVICE WATER SYSTEM FAILURES AND DEGRADATIONS (1986 -1995)

FEBRUARY 1998 Prepared By:

Mohammed Shualbi James R. Houghton Reliability and Risk Assessment Branch -

Safety Programs Division Office for Analysis and Evaluation of Operational Data U. S. Nuclear Regulatory Commission i

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!' EXECUTIVE

SUMMARY

This report documents the third study performed by the Office for Analysis and Evaluation of Operational Data (AEOD) on service water system (SWS) failures and degradations. This current study that covers SWS events from 1986 through 1995 utilized data from 1992 through 1995 to update the April 1993 AEOD SWS study, AEOD/S93-03, "Special Study, Operating Experience Feedback - Service Water System Failures and Degradations," which covered the years 1986 through 1991. The data were obtained from Licensee Event Reports (LERs), NRC's Service Water System Operational Performance inspection (SWSOPI) program, the Individual Plant Evaluation (IPE) program reports, and the Accident Sequence Precursor (ASP) studies.

The combined data from 1986 through 1995 were used in this report.

This report evaluates the safety performance of service water systems and the impact of licensee and NRC Initiatives on SWS performance. The report characterizes LERs into Safety Significant SWS LERs and other SWS LERs. It further distinguishes Safety Significant SWS LERs by their nature and effect on the system. Analyses of the trends in and contriuutions to the Safety Significant LERs foim the basis for the assessment of the overall safety performance and the effectiveness of NRC and licensee activities.

Additional evaluations include analysis and trending of SWS LER cause mechanisms, regional performance, and review of IPE and ASP Information relating to SWS events.

Background

The original service water system study, NUREG 1275, Volume 3, " Operating Experience Feedback Report - Service Water System Failures and Degradations,"

indicated that SWS performance required regulatory attention based on the perception that the safety significance of service water system failures and degradations was high and warranted corrective actions to reduce both the frequency and potential consequences of ope,ating events. In response to this report and other concems, the NRC issued Generic Letter (GL) 89-13 which addressed concerns for failures and degradations due to biofouling, corrosion, erosion, and silting (mechanistic causes) and to design, personnel, and procedural deficiencies (nonmechanistic causes). In addition, the NRC instituted the SWSOPI program to evaluate licensee performance of GL 89-13 issues.

A follow-on study (April 1993) determined that the nonmechanistic cause categories accounted for a large number of events, with the personnel / procedures errors category predominant. None of the operating events in the LERs during the period studied in the second report (1986-1991) caused actual total system failure (Safety Significance Category 1). Of the 56 events during this period,14 resulted in conditional SWS failures (complete failure of all redundant SWS trains but recovery occurred in sufficient time to avoid safety systems failures) or potential SWS failures Uhe SWS system was declared inoperable but no actual or conditional SWS failure occurred).

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Methodology in the approach to classifying events for this current study, LERs were reviewed for the ,

period 1986 - 1995 and classified into one of six Safety Significance Categories as indicated in the table below. Of the 579 SWS related LERs reviewed,147 (approximately 25%) were classified es Safety Significant LERs. The categories of Safety Significant LERs are briefly described as follows:

Safety ~

Significance Number Cateacry 11112 LY2n11 Demerintion 1 Actual Total failure of SWS 0 Total loss of SWS with damage to equipment required to provide core cooling.

2 Actual total Failure + Conditional 9 Conditional totai toss of SWS recovered prior to damage to equipment required for core cooling.

3 Potential Total Falture/ 39 Potential total falture of the SWS was ident. fled, but Degradation no actual falture occurred.

4 Actual Partist falture 22 Actual failure to one train of SWS, usually a comonent failure in the train caused loss of a train.

$ Potential Partial fatture/ 14 Potential loss or degradation to one train of Degradi(lon SWS.

6 Falture/ Degradation of 63 Failure to a specific support system heat exchanger Another System caused by SWS without other effect on SWS.

Findings The major findings relating to the review of the SWS operating experience are:

(1) There were no failures of SWS that resulted in an actualloss of core cooling capability. The few short term losses of SWS (less than 2% of the 579 reported SWS events) that had an impact on core cooling capability were identified and recovered promptly. These involved four "at power" events and five events during shutdown operations. For the "at power" events, the recovery time was usustly less than 30 minutes.' Most of the "at power" events involved failure of one train while the other redundant train of SWS or emergency power was out-of service for maintenance or testing. Several of the shutdown events required a longer recovery time (approximately four hours). However, recovery occurred without any significant impact on core cooling or damage to equipment served by the SWS.

(2) The analysis of the safety significance of the events indicated that e Events in which one train of SWS was actually lost accounted for a little 8

During these events preferred (offsite) power was available. However, had there been a loss of offsite power, service water would have been required within about 15 minutes to provide cooling to emergency diesel generators.

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less than 4% of the 579 reported SWS events. These usually involved failure of one SWS pump, thus affecting redundant availability of service water to dependent ESF systeme (e.g., EDGs, ECCS).

e The majority of SWS events involved actualloss of a specific support system component (e.g., EDG heat exchanger due to debris, sitt, or valve misalignment) or conditions with the potential for causing loss of one or more SWS trains due to design or procedural deficiencies. Examples would include (a) all service water pumps performance was degraded below design due to design deficiencies and (b) improper testing sequence resulted in securing the only operable service water pump prior to completing testing on the pump being returned to service).

(3) Approximately 12% (17 of 147) of the Safety Significant SWS events were also identified as precursor events in t'io ASP program. The number of ASP events relating to SWS problems is about 8% of the total 219 ASP events. The majority of these ASP SW3 events involved the loss of a specific support system heat exchanger, used for AFW or RHR (Safety Significance Category 6) or involved conditions with a potential for total failure of the SWS, usually the SWS pumps (Safety Slgnificance Category 3). The conditional core damage probabilities associated with these ASP events ranged from 1.3E 6 to 4.8E-4. These CCDP ranges are consistent with the IPE results for SWS related initiators for the population of plants.

(4) No trend was detected in the annual rate of all SWS LERs (579) over the period 1986-1995. However, the number of Safety Significant SWS LERs (Category 2-

6) increased over the 1986 through 1995 period. Licensee programs in response to GL 89-13 efforts played a significant role in identifying safety significant SWS LERs. Of the 147 Safety Significant SWS LERs,46 appear to have been identified as a result of efforts related to GL 89-13. This study found no trend (Increase or decrease) in the number of Safety Significant LERs when these 46 events related to GL 89-13 are removed from the database. Figure ES-1 shows a plot of the Safety Significant SWS LERs.

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, am ma summunen -+-8 5 Lins s (5) A SWSOPl review was performed to see if new safety significant items were found in the CWSOPIs that were not in operating experience, and to see if inspection findings were connistent with operating experience. Six LERs were generated as a result of SWSOPl findings including one Safety Significance Category 6 LER (specific support system heat exchanger) and five LERs that were not classified in the Safety Significance categories. The SWSOPIs were primarily reviews of the design bases and licensee compliance with regulatory requirements for processes to monitor and verify continued applicability of the design bases. Program and process reviews formed the bulk of the inspection instructions and the 15 dings reflect issues predominantly related to program and process deficiencies rather than operational failures or degradations.

(6) The IPEs indicate the peccentage of CDF attributable to SWS failure is about 13% for PWR plants and 7% for WR plants. There was no statistically significant trend (increase or decrease)il the relative contribution to CDF among BWRs or PWRs with respect to plant age. This indicated that the data are v

insufficient to conclude that " aging" effects are a significant contributor to the IPE results.

Conclus!ons Licensee activities in response to GL 8913 appear to have been successfulin identifying safety significant programmatic and design related issues affecting SWS ,

performance. Licensee GL 89-13 efforts primarily identified problems of the " Potential l

Failure / Degradation" type rather than problems of the " Actual Failure" type. This is  !

consistent with the intent of one of the GL 89-13 requirernents to verify design I adequacies and maintenance programs. This is indicative of successful efforts to identify and correct design and maintenance issues which might become operational problems if left unattended.

Data for this review of SWS operating experience were gathered during the period of GL 8913 formulation and implementation. Since GL 89-13 activities were completed relatively late in the period, it is not possible to assess the overallimpact of GL 89-13 on SWS performance. However, the frequency and nature of the SWS events reported supports the risk implications of SWS performance indicated in IPE and ASP analyses.

These analyses indicate that for the general population of plants the SWS performance was a measurable, but not dominant, contributor to risk. Plant-specific risk contributions can vary.

Recommendations AEOD should continue to monitor the overall industry experience as indicated by LERs and the additional reliability data that will become available via the industry's Equipment Performance Information and Exchange (EPIX) system. Trending should be updated with a minimum of two additional years of experience to determine if safety significant improvements in SWS performance have actually been achieved and to assure that new or unidentified SWS safety concems are not present. The purpose of this work will be to determine if the operating experience indicates safety significant improvement in performance as SWS actions in response to GL 89-13 are completed NRR should evaluate the effectiveness of future SWS inspections (SWSOPIs or other inspections of SWS performance)in light of the risk significance of the operating experience discussed in this report. Future inspection activities should be more focused on the generic risk insights in this study with respect to safety significant SWS performance in consideration of plant specific PRA results and relevant operating experience.

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TABLE OF CONTENTS Eage 1

BAC KG R O U N D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 ,

2 SCOPE................................................4 3 APPROACH AND METHODOLOGY . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 s

3.1 LERData................................................ 5 3.2 GL 89-13 and SWSOPl Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3.3 ASPData................................................ 8 3.4 IPEData................................................ 9

4 RESULTS ..............................................10 4.1 Assessment of LER Data (1986 through 1995) . . . . . . . . . . . . . . . . . . . 10 4.2 SWSOPl Findings (1991 through 1995) e'id Assessment of GL 89-13 Effort s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 4.3 Assessment of SWS ASP Data (1986 through 1994) ............... 29 4.4 Assessment of SWS IPE Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 5 FINDINGS, CONCLUSIONS, AND RECOMMENDATIONS . . . . . . . . . . 32 5.1 Fi n d i n g s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2 .

5.2 Conclu sio n s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 5.3 Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 6 RE F ERE N C ES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 APPENDIX A - TABLES ,

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FIGURES Elgute Eage 1

All SWS LERs (Mechanistic & Non-Mechanistic) . . . . . . . . . . . . . . . . . . 13 2 Normalized Occurrence Rates for all SWS LERs by Cause Categories . 14 3 Pie Chart Breakdown of the Personnel Errors Subcategory for SWS Related LERs for the Period of i986 to 1995 . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4 Pie Chart Breakdown of the Procedural Errors Subcategory for SWS Related l LERs for the Period of i986 to 1995 . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 5 Gafety E;gnificant SWS LERs (Mechanistic & Non-Mechanistic) . . . . . . . 20 6 Quantity Mechanistic & Non-Mechanistic SWS LERs vs. Safety S ig nifica n ce C at eg ory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 l 7 Normalized Occurrence Rates by Safety Significance Categories for Safety Significant SWS LERs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 8 Breakdown of the Safety Significance Categories into their Causes . . . . 23 9 SWSOPl Findings by Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 10 SWSOPl Findings / Plant inspected vs. Calendar Year . . . . . . . . . . . . . . 27 11 IPE Fraction of Total CDF due to SWS for BWR IPEs . . . . . . . , . . . . . . 31 12 IPE Fraction of Total CDF due to SWS for PWR IPEs . . . . . . . . . . . . . . 31 viii

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l APPENDIX A-TABLES l Iable P_ age l 1 SWS Related LERs from 1/1/86 to 12/31/95 . . . . . . . . . . . . . . . . . . . . . A-1 1 2 Total SWS Failures - Conditional - Category 2 ...................A-12 3 Potential Total Failure / Degradation of SWS - Category 3 . . . . . . . . . . . A-13 4 Actual Partial Failure of SWS - Category 4 . . . . . . . . . . . . . . . . . . . . . A-17 5 Potential Partial Failure /!.segradation of SWS - Category 5. . . . . . . . . . A-20 6 SWS Causes Failure / Degradation of Another System

- C a t eg o ry 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2 2 7 SWS Related ASP Events for the years 1986 through 1994 . . . . . . . . . A-29 4

8 Percent of CDF Attributable to SWS Failure (From IPE Analyses Submitted to NRC) ............................... A-30 9 Summary of SWSOPI Report Individual Findings and issues . . . . . . . . A-31 10 NRC SWSOPl Report Examples - T issues . . . . . . . . . . . . . . . . . . . ............................

. ypes of Deficiencies or A-35 11 Normalized Occurrence Rates for all SWS LERs by Cause C a teg ories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-36 12 Normalized Occurrence Rates for Safety Significant SWS LERs by Cause Categories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-37 l

i 13 Normalized Occurrence Rates for Safety Significant SWS

, LERs by Significance Categories . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-38 l

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l' ACRONYMS '

AEOD Office for Analysis and Evaluation of Operational Data, NRC BWR Boiling Water Reactor CCW Component Cooling Water CDF Core Damage Frequency ESW Essential Service Water IPE Individual Plant Evaluation IST In Service Test w 1 C'd Licensee Event Report LOCA Loss of Coolant Accident LOOP Loss of Offsite Power NPRDS Nuclear Plant Reliability Data System NRC U.S. Nuclear Regulatory Commission PRA Probabilistic Risk Assessment RES Office of Research, NRC SCSS Sequence Coding and Search System SWS Service Water System SWSOPl Service Water Syst' .i Operational Performance inspection UHS Ultimate Heat Dink X

1 BACKGROUND In 1988, the Office for Analysis and Evaluation of Operational Data (AEOD) ccmpleted the first Service Water System (SWS) study (Ref.1) which provided a comprehensive review and evaluation of SWS failures and degradations observed at operating light water reactor nuclear power p! ants for the period of 1980 to 19P The review and evaluation focused on identifying causes of failures and degt ions in SWSs; the adequacy of corrective actions, both planned and implementee and the safety significance of the operating events. The results indicated that the safety significance of SWS failures and degradations was high. The failures and degradations in the SWS were due to a variety of causes and had adverse impact on a large number of interfacing safety-related systems and components required for accident mitigation.

The causes of failures and degadations included various fouling mechanisms (e.g.,

sediment deposition, biofouling, corrosion and erosion, pipe coating failure, calcium carbonate), as well as foreign material and debris intrusion; flooding; equipment failures; personnel and procedural errors; and seismic and other design deficiencies.

Interfacing systems and components adversely impacted by a SWS failure or degradation included the component cooling water system, emergency diesel generators, emergency core cooling system pump coolers and heat exchangers, the residual heat removal system, containment spray and fan coolers, control room chillers, and reactor building cooling units.

The 1988 study identified 980 opeiating events in which the SWS v>as involved. Of these,276 had potential generic safety significance and were evaluated further in the study. The 1988 study recommended that licensees:

(1) Conduct, on a regular basis, performance testing of all heat exchangers that are cooled by the SWS and that perform a safety function to verify heat transfer capability; (2) Verify thi the SWS is not vulnerable to a single failure of an active component; (3) Inspect, on a regular basis, important portions of the piping of.the SWS for corrosion, erosion, and biofouling; and (4) Reduce human errors in the operation, repair and maintenance of the SWS.

On July 18,1989, as a result of concern with the compliance of nuclear power plants' SWSs with General Design Criteria (GDC) 44,45, and 46 and quality assurance requirements, the NRC issued Generic Letter (GL) 89-13. " Service Water System Problems Affecting Safety-Related Equipment,"(Ref. 2). NRC Recommended Actions in this GL were based on the findings of the 1988 study. The GL required licensees and applicants to supply information about their respective SWSs to assure compliance-with aoplicable regulations and to confirm that the safety functions of these systems 1

were being met. On November 28 and 30 and December 5 and 7,1989, the NRC conducted workshops on the GL during which the NRC answered questions related to the GL. On April 4,1990, the NRC issued Supplement 1 to GL 89-13 (Ref. 3) to clerify the requirements specified by GL 8913. This supplement included a list of the questions and answers read into transulpts during the workshops. In addition, the Office of Nuclear Reactor Regulation (NRR) developed a task action plan to resolve SWS problems that appeared to be continuing after the release of GL 89-13. This plan included tasks for: (1) establishing a single focal point within the NRC for resolving SWS problems, (2) coordinating the resolution of identified weaknesses in Probabilistic Risk Assessm3nt (PRA)/Probabilistic Safety Assessment (PSA) methodology, (3) identifying specific concerns being addressed in Generic issue GI-153, " Loss of Essential Service Water in LWRs," and considering alternate approaches for SWS issue resolution, (4) developing additional generic communications, and (5) developing, performing, and evaluating SWS audits (Ref. 4). To monitor the effectiveness of the task action plan, NRR requested AEOD support in analyzing and developing trends from SWS operating data (Ref. 5).

With the issuance of GL 8913 in mid 1989 and initial NRC audits of plant SWSs for compliance, NUMARC was requested, during a joint meeting in November 1991, to respond to NRC staff concems regarding the status of the implementation of the recommendations in the GL and the overall condition of SWSs. NUMARC responded to the staff with an initialletter in January 1992. A second letter in April 1992 contained additional details on Licentee Event Reports (LERs) used as a database in the initial letter, in their initialletter, NUMARC stated their understanding of the NRC staff's expressed concems to be "that industry was not aggressively pursuing the implementation of GL 89-13," and summarized the bases for the concems as: 1) the large number of events relating to SWS operability,2) the impodance of the SWS as a contributor to overall risk of core melt, and 3) that SWS events continue to occur.

NUMARC also reviewed SWS LERs for the period 1990 through 1991. They compared these events with those in the 1988 study and analyzed the data using the same nine cause categories used in the 1988 study. NUMARC stated that 98 SWS events occurred in this time period, and that they evaluated 33 of these as potentially safety significant. They fudher stated that these 33 events represent a greater than 50 peicent reduction in the average annual number of significant events since the 1980 through 1987 time frame. The second letter, in response to an NRC request, provided the NRC staff with the listing and brief description of the 98 LElis and an additional,-

separate listing of the 33 "Potentially Safety Significant Service Water LERs."

NUMARC concluded that:

"Our assessment leads us to conclude that utilities (licensees) are devoting significant resources towards service water improvements and are aggressively 2

pursuing the implementation of Generic Letter 89-13. The results of the Infilal implementation Indicate improvement in service water system reliability.

Acco?dingly, we believe that complete implementation of the generic letter by the entire Industry will further improve service water reliability. The concems raised 1 by the NRC staff at the November (1991) meeting do not appear to be supported by recent service water reliability history and the St. Lucie inspection results do not provide rationale for additionalindustry actions beyond inose requested by Generic Letter 89-13. In addition, it should be noted that the Generic Letter 89-13 actions are the beginning of a monitoring and improvement program which will continue beyond the initialimplementation dates."

In response to the NRR request for AEOD support in analyzing and developing trends from SWS operating data, a second AEOD SWS study,"Special Study Operating Experience Feedback - Service Water System Failures and Degradations," AEOD/S93-03, (Ref. 6) dated April 1993, reviewed LER operating experience from 1986 through 1991. The study determined that the nonmechanistic cause categories accounted for a large number of events, with the personnel / procedures errors category predominant.

The study found no total SWS failure events in the LER database for the time period evaluated, in addition to evaluating LERs, the study also evaluated SWS component failures as recorded by the Nuclear Plant Reliability Data System (NPRDS). The study noted that the mechanistic cause categories for silt, biofouling, corrosion / erosion, and debris can be more significant for plants located near shorelines or large, shallow rivers.

The study concluded that LER operational experience data from 1986-1991 showed no discernible trend of increased or decreased risk from the SWS.

The objective of this update to the second SWS study is to review and analyze LER and other SWS related data for the years 1986 through 1995 and provide feedback to NRR of findings and conclusions.

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l 2 SCOPE '

The SWS .y concerns degradation or failure of SWS functions. It is concerns )nly with those operations of SWS tha' are required for plant safety, and which , suld be required to function to mit'ste transient events and accidents ar., allow safe shutdown of the plant. This update to the study extends the 1986 through 1991 stldy by evaluating LER data for the years 1992 through 1995 and integrating the data from both periods to provide a longer term assessment of SWS performance. In addition, the update provides insights related to SWS events evaluated in the Accident Sequence Precursor (ASP) program, and findings identified by NRR's service water systern operational performance inspection (SWSOPI) program. Lastly, the update examines the general risk implications of SWS events by examining the percent contribution of SWS related failures to core damage frequency as indicated in Individual Plant Examinations (IPEs) which were conducted under GL 88-20 (Ref. 7).

Data for this update were obtained from several sources. LERs were obtained from the NRC's Sequence Coding and Search System (SCSS) database which is maintained by Oak Ridge National Laboratory; ASP Events were obtained from applicable volumes of NUREG/CR-4674, " Precursors to Potential Severe Core Damage Acciderits;" and SWSOPl findings were obtained from NRR's SWSOPl database. In addition, general risk implications involving the SWS were examined through utilization of the IPE database developed by the Office of Nuclear Regulatory Research (RES).

The periods assessed by this study varied depending on the type of data analyzed. For LERs, the study focused on updating the prior study with data for the years of 1992 through 1995. For SWSOPl findings, the entire NRR SWSOPl database y as considered. The SWSOPI database provided information for the period of 1991 through 1995. For ASP, the period of 1986 through 1994 was assessed.

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t 3 APPROACH AND METHODOLOGY 3.1 LER Data Safety system malfunctions that result in the system not being operable as defined by the respective plant Technical Specifications (TS) or Safety Analysis Report (SAR) are required by 10 CFR 50.73 to be reported in LERs.

Inoperability, as used in this report, describes LER reported events in which the system did not meet the operability requirements identified in the TS or SAR.

Inoperabilities include such events as seismic deficiencies, late performance of a test, etc. Failure, on the other hand, is used to describe inoperabilities in which the safety function of the system is lost. These include such events as failure to start or failure to run. LERs assessed in this study were of the total or partial system "inoperability" type (including potential inoperability) and may not have resulted in actual s stem failures.

LER data were used to assess the performance of the SWS over the period of the study. These data were evaluated to identify trends of LERs and the importance of such trends as related to SWS performance. Trends were separately analyzed for: 1) total number of LERs,2) number of safety significant (Significance category) LERs,3) LERs of different Significance categories, and

4) LERs of different causes, in addition, regional analysis of LER data was performed for plants located in the different NRC Regions.

3.1.1 SWS Failure /Dogradation Cause Categories As was done in the two prior studies, a breakdown of the additional 1992 tnrough 1995 SWS LER failure events were classified by cause. The cause categories used for SWS failures and degradations are as follows:

Category A - Silting / Sedimentation Category B - Blofouling Category C - Corrosion / Erosion Category D - Foreign Material / Debris Category E - Personnel / Procedural Errors Category F - Design / Seismic Deficiencies Note: Cetegories A D are considered " mechanistic" and categories E and F are considered " nonmechanistic".

3.1.2 SWS Safety Significance Categories e

in addition to grouping events by failure causes, the LERs were evaluated according to their safety significance. This categorization of reported SWS 5

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events considers the extent of system or train failure, the likelihood of system recovery, and the actual or potentialimpact on other safety systems / functions reporteo in the LER. While this second ranking is still qualitative it does provide a means of distinguishing the more serious events from the rouilne or less important ones. The Safety Significance categories used in this study are:

Category 1 - Actual Total Failure of SWS Category 2 - Actual Total Failure of SWS - Conditional Category 3 - Potential Total Failure / Degradation of SWS Category 4 - Actual Partial Failure of SWS Category 5 - Potential Partial Fal!ure/ Degradation of SWS Category 6 - SWS Causes Failure / Degradation of Another System 3.1.3 SWS Safety Significance Category Definitions

• Category 1 - Actual Total Failure of SWS Category 1 is defined as a comotete failure of all redundant SWS trains such that the recovery of the safety function did not occur, or is judged could not have occurred, within the time necessary to avoid degradation / failure of many or all of the safety systems (e.g., emergency A.C. power, engineered safeguards systems, etc.) which rely on the dWS for heat removal. Category 1 is considered to have the highest safety significance of the categories defined in this study.

• Category 2 - Actual Total Failure of SWS - Conditional Category 2 is defined as a complete failure of all redundant SWS trains, where recovery occurred, or is judged coulo have occurred within the time necessary to avoid degradation / failure of many or all of the safety systems (e.g., emergency A.C. power, engineered safeguards systems, etc.) which rely on the SWS for heat removal. The necessary recovery time may vary with specific plant design, reactor type, and mode of operation. Although these events are less significant than the previous category, they are still important. Without timely discovery and intervention, events of this

' ategory could result in the types of consequences associated with lategory 1 events (i.e., core damage). Category 2 events are further grouped into two subcategories, namely, "at power" events and shutdown events. An example of Category 2 events is a situation where all SWS pumps were inadvertently placed in a " pull-to-lock" condition where they would not have automatically started when demanded. However, operator discovery and correction of the switches, either before or at the time of the need for the SWS, results in SWS recovery.

6

o Category 3 - Potential Total Failure / Degradation of SWS Category 3 'a defined as a potential failure or degradation of all redundant SWS trains due to a design or other deficiency which results in the SWS being declared inoperable, but no actual or conditional total failure occurs (i.e., did not meet Category 1 or 2 definitions). This category covers situations where complete SWS failure could "potentially" result but does not. An example is a situation where all SWS trains were declared technically inoperable for some tirno due to the discovery of a condition that placed the system outside of its design bases (e.g., service water strainers rot seismically qualified). However, since an actual total failure of the SWS did not occur, it is categorized as potential.

• Category 4 - Actual Parthi Failure of SWS Category 4 is defined as the actual failure of one or more SWS trains but not the entire system. It is important to note that for an event to be classified as Category 4, operability of at least one train of the SWS must have been maintained throughout the event. An example of this category is a situation where a plant shutdown was required when the "B" service water train was inoperable due to biofouling for a time that exceeded Technical Specification limits.

• Category 5 - Potential Partial Failure / Degradation of SWS Category 5 is defined as the potential failure or degradation of one or more SWS trains, but not the entire system. As was done in the previous category, it is important to note that for an event to be classified as Category 5, at least one train of the SWS must have not been affected by the event. An exaneple of this category is a situation where design basis reconstitution efforts uncovered two scenarios in which a single failure could threaten operability of a cooling water pump.

• Category 6 - SWS Causes Failure / Degradation of Another System Category 6 is defined as the total or partial failure, or degradation of a system interfacing with SWS due to SWS related causes (i.e., silting or biofouling achieved through the SWS interface, SWS valve misalignment, etc.). This category, for specific support systems only, is mutually exclusive of the other five categories, as the SWS has neither failed nor degraded. An examples of this category is a situation.where an auxiliary feedwater pump oil cooler was found isolated from the SWS due to a mispositioned system interface valve. Another example is a situation where the containment fan coolers were declared inoperable due to 7

I

l sitting, biofouling, or debris, o Other All other SWS events that are considered less safety significant than Categories 1 through 6 above.

3.2 GL 89-13 and SWSOPl Findings The NRC issued Temporary Instruction (TI) 2515-118 (Ref. 8) to assess licensees' planned or completed actions in response to the recommendations of GL 8913. SWSOPIs are performed as area-of-emphasis inspections in accordance with this Tl. This study evaluated the impact of GL 89-13 efforts, including SWSOPIs, on SWS performance by analyzing the effect of these efforts on the trends of LERs. This was accomplished by first identifying the LERs that may have resulted from either GL 89-13 or SWSOPl efforts; and then, analyzing trends of LERs excluding those identified in the first step. These trends were then compared to the trends identified in the LER section of the study to identify any effects that GL 89-13 efforts may have had. This was only performed for the LERs categorized in Significance Categories 1 through 6.

When reviewing the findings of this section, it is important to keep in mind the relationships and differences between problems identified as a result of efforts such as GL C413 inspections and those identified through operating experience.

The types of findings associated with such efforts as GL 89-13 are primarily focused on system or component design capability and the potential for operation under specific design basis conditions. Operating experience, on the other hand, is generally constrained to actual failures found during the more frequent operating states or to failures uncovered by routine testing. While there is some overlap, operating experience failures mostly identify reliability issues.

From a risk (safety) perspective, both capability and reliability are important.

However, the uniqueness of various SWS designs and the abt.ance of integrated risk models of these systems limits the ability to assess the relative importance of each of these types of findings.

3.3 ASP Data As stated in NUREG/CR-4674, " Precursors to Potential Severe Core Damage Accidents: 1994 A Status Report," the primary objective of the ASP Program is to systematically evaluate U.S. nuclear plant operating experience to identify, document, and rank those operating events which were most significant in terms of the potential for inadequate core cooling and core damage. In addition, the program has the following secondary objectives: (1) to categorize the precursor l events for plant specific and generic implications, (2) to provide a measure which 8

l l

I

can be used to trend nuclear plant core damage risk, and (3) to provide a partial check on PRA-predicted dominant core damage scenarios (Ref. 9). This study identifies SWS related ASP events and provides insights on the significance and causes of such events. No trending of the data from the ASP program was puformed due to sparsity of data and changes to the methods incorporated during the period which could impact ASP analysis trend results.

3.4 IPE Data IPEs performed under GL 88 20 list the more important core damage scenarios due to internal events, and the expected core damage frequency per reactor year due to each of these scenarios. The IPE database includes information on system to system dependencies, core damage frequnneles for the different scenarios, and other related attributes such as coupling between systems or trains. In addition, the IPE database prov8 fes the total core damage frequency estimate per reactor year for all accident sequences. Therefore, to find the fractional contribution of an individual scenario type to a plant's total core damage frequency one can divide the sum of the core damage frequancies attributable to that scenario type by the total core damage frequency. This was performed for the SWS in this study. The relative importance of the SWS to CDF for PWR and BWR plants and the trend of this importance vs. commercial operation start dates also were assessed.

This study addresses only IPE scenarios which involve the loss of SWSs or functions of these systems that are required for safe shutdown as an initiating event. For this study, the analysis of the contribution of the SWS to the CDF was conservative in that it was not limited to the essential service water system. It also included transients through to the ultimate heat sink and for PWRs, component cooling water system tranGonts. The following are the IPE transient initiators used in this study to characterize SWS contribution to CDF:

For BWRs: Transients were T-ESW or T UHS.

For PWRs: Transients were T-ESW, T-CCLV, and T-UHS.

IPE studies also account for core damage cutsets from scenarios which contain SWS failures in combination with other initiating events and component failures.

Since the IPEs do not provide detailed cutsets for core damage sequences, no analysis of the SWS contribution to CDF was performed in this study for the scenarios where SWS was not the initiating event .

9

4- RESULTS 4.1 Assessment of LER Occurrence Rate Data (1986 through 1995)

For the period 1986 through 1995, a totai of 579 SWS related LERs were identified through a search of the SCSS database. Of the 579,218 occurred during the update period 1992 through 1995. Appendix A, Table 1 provMes a listing of all 579 LERs. .

A plot of the 579 LERs vs. the calendar year they were reported is provideC in Figure 1. Regression analysis on the data detected no trend in the rate of tual LERs generated over the entire period, in addition, Figure 1 shows a breakdo vn of the LERs into mechanistic causes (Cause Categories A, B, C, and D) and non mechar 'stic causes (Cause Categories E & F). This breakdown, shows that non mechanistic LERs outnumbered mechhulstic LERs by a ratio of three to one.

4.1.1 Cause Category Results A breakdown of the 579 LERs into Cause Categories achieved the following approximate distribution: '

e. Cause Categor) A (Sitt & Sedimentation)

The silt and sedimentation events (Figure 2a - Category A) were predominantly caused by lower water level in the supply to the SWS for plants located near fresh water rivers and lakes. The numb 9r of events '

and percentage of the total SWS events (37 events; 6.4%) is not .

considered significant any no trend is evidont.

• Cause Category B (Blofouling)

The biofouling events (Figure 2b - Category B) were predominantly caused by ingress and growth of clams and mussels in plants located near warm, fresh water rivers and lakes. The number of events and percentage of the total SWS events (31 events; 5.4%) is not considered significant and no trend is evident.

e Cause Category C (Corrosion / Erosion)

The corrosion / erosion events (Figure 2c Category C) were predominantly due to exposure of SWS piping to uninhibited water, resulting fr. corrosion. The number and percentage of the total SWS events (58 events; 10%) is not considered significant and no trend is evident. .

10

e Cause Category D (Foreign Material / Debris)

The foreign materials / debris events (Figure 2d Category D) were mostly due to storm-carried debris into the SWS and resulting clogging of valves and heat exchangern. The number of events and percentage of total i

SWS events (17 events: 2.9%) is small and is not considered significant.

No trend is evident.

• Cause Category E (Personnel / Procedural Errors)

The personnel / procedural errors (Figure 2e Category E) were predominantly due to valve and equiprnent alignment errors. The number and percentage of total SWS ewnts (267 events 46%)is high and considered significant. No trend is evident.

Due to the relatively large number of events identified in Cause Category E, the category was divided into two subcategories, Personnel Errors and Procedural Errors. This resulted in an approximately even distribution between the two subcategories with 129 LERS being attributed to personnel errors and 138 LERs being attributed to procedural errors. The two subcategories were then further evaluated and causal breakdowns of each are shown in Figures 3 and 4, respectively.

Figure 3a shows that approximately 37% of the 129 LERs attributed to personnel errors occurred during valve or equipment alignment, while 21% occurred during maintenance, modifications, or installatinn tests.

Figure 4a shows that approximately 31% of the 138 LERs attributed to procedural errors occurred in valve or equipment alignment procedures, while 28% occurred in inservice test (IST) or surveillance test procedures.

Figures 3b and 3c show that the highest percentage of personnel errors continue to be related to valvo and equipment alignment.

Figures 4b and 4c show that the highest percentage of procedural errors have shifted from valve and equipment alignment from the previous study (1986 - 1991) to IST/ Surveillance Testing for this update (1992 - 1995).

11

• Cause Category F (Design / Seismic Deficiencies) -

The design / seismic deficiencies events (Figure 2f - Category F) were predc:r,inantly design deficiencies among a variety of SWS components.

The number and percentage of total SWS events (169 events: 29%) were

- relatively high, but varied in applicability to components and to specific plant SWS design. Therefore, these events were considered as lesser significance than the Category E events, above. .

Normalized plots of the different Cause Categories over the period of the study -

are provided in Figure 2. Normalization was necessary because the number of operational reactors varied over the period due to initial start-ups and permanent shutdowns of plants. The ordinate of each plot was achieved by dividing the number of LERs by the reactor-years of operation for that year. Regression analysis performed on the data of each of these categories indicated no trends.

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4.1.2 Safety Significance Category Results Furtner evaluation of the 579 SWS LERs placed 147 of them into Safety Significance categories with the following categorization:

• Safaty Significance Category 1 (Actual Total Failure)

There were no events in this category. .

Safety Gignificance Category 2 (Actunt Total Failure - Conditional)

' Of the 9 events in this category,4 were "at power" and 5 were during shutcown operations. For the "at power" events, the recovery time was usuairy less than 30 minutos, with no observed damage to equipment served by the SWS. Most of these "at power" events involved failures of one train following another train of SWS or emergency power being out-of service for maintenance or testing. For several of the shutdown events, a longer recovery time (approximately 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />) was reauired. However, recovely occurred without any significant impact on core cooling or damage to equipment served by the SWS. One of these shutdown events, Oconee 1, was also an SWS related ASP event (see Appendix A, Table 7).

Safety Significance Category 3 (Potential Total Failure / Degradation)

For the 39 events in this category, the total SWS was aeclared inoperable.

However, although failures were postulated or degradations occurred, no actual failures of the total SWS were observed. Inoperability due to conditions outside the design basis that could result in totalloss of the SWS typified some of the events in this category. Seven of the 17 SWS related ASP events were also in this category (see Appendix A, Table 7).

Safety Significance Category 4 (Actual Partial Failure)

For the 22 events in this category, actual failure of one train typified the events, usually due to a pump or piping component failure. These usually involved failure of one SWS pump, thus affecting redundant availability of service water to dependent ESF systems (e.g., EDGs, ECCS). The majority of SWS events involved actualloss of a specific support system component (e.g., EDG heat exchanger due to debris, siit, or valve misalignment) or conditions with the potential for causing loss of one or more SWS trains due to design or procedural deficiencies (e.g., (a) all service water pumps performance was degraded below design due to design deficiencies and (b) improper testing sequence resulted in 17

securing the only operable se:Vice water pump prior to completing testing on the pump being returned to service). One of these events was also an SWS related ASP event (see Appendix A, Table 7).

• Safety Significance Category 5 (Potent. Partial Failure / Degradation)

For the 14 events in this category, potential loss or degradation of one train typified the events, usually due to SWS components (e.g., pump, strainer, piping, or valves).

• Safety Significance Category 6 (Failure / Degradation of Another System)

For the 63 events in this category, failure or degradation of specific support system heat exchangers served by the SWS typified the events, usually caused by debris, biofouling, or silt / sedimentation. Eight of these events were also SWS related ASP events (see Appendix A, Table 7).

Appendix A, Tables 2 through 6 provide a listing of LERS by Safety Significance categories. This categorization shows that approximately 25% of all SWS LERs reported for the period of the study (147 of 579 LERs) were pl aced in the Safety Significance categories. However, this breakdown also shows that of the 147 LERs, 63 LERs (approximately 43%) involved failures of interfacing specific support system components between the SWS and other systems. These LERs would not have affected the ability of the SWS to provide cooling for the other systems it supports. This leaves 84 LERs (14.5% of the total 579 LERs) which were placed in Safety Significance categories and which could have affected the atiility of the SWS to function as designed. Of the 84 LERs,37% were actual failures, while 63% were potential failures. Fifty-Seven percent affected the entire SWS while 43% affected only part of the SWS. A most important finding of this breakdown is that no events were classified as Actual Total Failure of SWS (Category 1) and that only 9 events were classified as Actual Total Failures of SWS - Conditional (Category 2).

No Vend was detected in the annual rate of all SWS LERs (519) over the period 1986 -1995. A plot of the 147 Safety Significant LERs vs. the calendar year they were reported is provided in Figure 5. Regression analysis on the data in this figure detected a slightly increasing trend over the period. In addition, the LERs were divided into mechanistic and non-mechanistic causes. This breakdown shows that these LERs are approximately evenly divided between the two. The breakdown also shows that the detected trend is mostly attributable to an increase in ;be non-mechanictic LERs.

A distribution of the 147 LERs among their Safety Significance categories is 18 I

provided in Figure 6. Figure 7 prou 3s normalized plots of the different Safety Significance categories over the period of the study. Normalization was achieved in the same manner as was discussed earlier for Figure 2. Regression analysis perform 3d on the data of each of these categories identified a slightly increasing trend for Safety Significance Category 3 (Potential Total Failure / Degradation). A strong increasing trend was identified for Safety

_' Significance Category 5 (Potential Partial Failure /Degradatic.). However, it

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should be notea that the number of these events (Category.5 only) is relatively small and that they have only been reported after the issuance of GL 89-13. In addition, the significance of the events in Category 5 (Potential Partial Failure / Degradation) is relatively minor when compared to the events of the other Safety Significance categories. No other trends were identified.

Causal breakdowns of LERs for each of the Safety Significance categories are 7 _ provided in Figure 8. These distributions show that Cause Categories E and F (Personnel / Procedural Errors and Design / Seismic Deficiencies, respectively) were the cause of approximately two-thirds of the LERs in Significance Categories 2 and 3 (events with actual or potential effects on the entire system).

The same two Cause categories were also the cause of just over half of the LERs in Safety Significance Categories 4 and 5 (events with actual or potential

_ ) effects on part of the system). In addition, slightly increasing trends were identified for Cause Categories C (Corrosion / Erosion), E (Personnel / Procedural y

Errors) and F (Design / Seismic Deficiencies).

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23 Figure 8. Breakdown of the Saftty Significance Categories into their Causes.

4.1.3 Regional Results An evaluation of LER data for the different NRC Regions was also performed.

Plants in the former NRC Region V and former NRC Region IV, were ansessed separately due to the relatively recent merger of the Regions. Norms..c "

Occurrence Rates were calculated by dividing the total number of LERs generated from plants in the NRC Region of interest by the tetcl number of reactor-years of operation achieved by those plants from 1986 through 1995. The results of this evaluation are presented in Tables A and B below.

Table A - Trends in At t SWS Events Former Former All Cause cateaorv Realon 1 Reaion 11 Reaton til Reaion IV Realon V Realons NormatizN 0.751 0.561 0.350 0.623 0.249 0.536 Occurrence Rates Mechanistic No Trend Decreasing No Trend No Trend No Trend No Trend LERS (Cat A D)

Non-Mechanistic No Trend Decreasing No Trend No Trend No Trend No Trend LERs (Cat E & F)

All LERs No Trend Decreasing No Trend No Trend No Trend No Trend Table B - Trenos in Saf ety Sionificance (Yt h ev Events former Former All Cause Cateaorv Reaton 1 Realon II Realon 111 Recion IV Reaton V Recions Normalized 0.204 0.148 0.076 0.138 0.065 0.136 Occurrence Rates Mechanistic Increasing No Trend No Trend No Trend No Trend No Trend (Cat A-D)

NwMech.snistic Increasing No Trend No Trend No Trend increasing.

Increasing Actual Failures incrcesing Decreasing No Trend No Trend No Trend No Trend (Cat 2 & 4)

Pot. Fallsras Increasins No Trend No Trend increasing No Trend increasing (Cat. 3 & 5)

All Signif. Increasing No Trend No Trend No Trend ?ncreasing Increasing Category LERs The results show that the normalized occurrence rates for plants in NRC Region ill and former NRC Region V, as identified by the analysis of all LERs and the analysis of the LERs in the Safety Significance categories are a factor of two less than those in the other Regions. Additionally, the number of LERs in Region 11 show a decreasing trend in mechanistic as well as non-mechanistic LERs when 24 l

considering al! LERs. Plants in Region ll show no trends for these categories when considering only Safety Significance category LERs.

Region I plants have increasing trends in both the mechanistic and non-mechanistic LERs among the Safety Signifhance category events.

The mechanistic LERs were predominantly due to an increase in reported corrosion / erosion causes in the 1993-1995 perit d. It is estimated that L

these were the result of increased SWS piping system inspections as a response to GL 89-13.

-The nor, mechanistic LERs were predominantly personnel / procedural deficiencies for valve and equipment alignment. There is no specific basis noted for the increasing trend.  !

4.2 SWSOPl Findings (1991 through 1995) and Assessment of GL 89-13 Efforts 4.2.1 SWSOPl Findings For the period of 1991 through 1995,32 NRC SWSOPIs (3 reduced scope and 29 full scope SWSOPIs) and 29 licensee self-assessments were performed. As a result of these efforts a total of 149 findings were identified in the NRR SWSOPl database. A listing of these findings is provided in Appendix A, Table

9. Figure 9 provides a breakdown of the types of findings identified. Tnis breakdown resulted in the following distribution:

System Design - 65 findings (43% of the 149 findings)

Operations & Maintenance - 46 findings (31% of the 149 findings)

Surveillance & Testing - 38 findings (26% of the 149 findings) in addition to the above distribution, a review of these findings found that approximately 39% of the findings involved routine activities such as maintenance, testing and surveillances which provide opportunities for licensee and/or other personnel to identify the deficiencies.

Figure 10 provides a plot of the number of findings identified per plant inspected for each year. This plot shows an increasing trend in the number of findings resulting from these efforts over the period of 1991 through 1995.

A review of the findings in the GWSOPIs database was performed to identify those findings that tesulted in LERs. Six LERs were generated directly fram SWSOPl findings including one Safety Significance Category 6 LER and five LERs that were not classified in the Safety Significance categories. The SWSOPIs were primarily reviews of the design bases and licensee compliance with regulatory requirements for processes to monitor and verify continued 25

applicability of the design bases. Program and process reviews formed the bulk of the inspection instructions and the findings reflect issues predominantly l related to program and process deficiencies rather than operational failures or degradations, l

26

Figure 9. SWSOPl Findings by Type Total Findings = 149 O&M 31 %

Design 43%

Testing 26 %

Figure 10 - SWSOPl Findings / Plant lespected vs Calendar Year 11 .

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.h d[$5adhI Ndl 1931 1992 1993 1994 1995 Calendar Year 27

r 4.2.2 Assessment of GL 89-13 Efforts A review of the 147 Safety Significance category LERs was performed to identify those LERs which appeared to have resulted from GL 89-13 efforts other than SWSOPIs or formallicensee self-assessments. in addition to the one LER identified as resulting from SWSOPIs,45 more LERs appeared to have been identified as a result of these efforts. Causal distribution of the 46 Safaty Significance category LERs resulting from GL 89-13 (SWSOPIs, self-assessments, or other efforts) and Safety Significance category distribution is provioed in Tables C and D below, ighlf C - Saf ety Stanificance Cateoorv LERs f rom GL 8913 Activities by cause Cateoorv Total GL 89 13 Percent GL 89-13 LERs to a ercent GL 89 13 LFRs in cause Cause Category LERs LERS Total LERt in Cause C & Cateaory to Total CL 6913 LEta A ($llt & 18 4 22% 9%

Sedimentation)

B (Blofouting) 23 11 48% 24%

C (Corrosion / 21 6 29% 13%

Lrosion)

D (Debris) 7 2 29% 4%

E (Personnet/ 42 9  ?.1% 20%

Procedures)

F (Design / 36 14 39% 30%

Seismic) gl 147 46 31% 100%

Tabte t) - GL 89-13 LERs hv Safety Siontficance Cateoorv Percent GL 89-13 ERs Safety Total GL 89-13 to Total LERs in Safety Percent GL 89-13 LERs in Signif.

Significance Cat. LERS LERs sianificance Cateaories Cateaory to Total CL 89-13 LERs 2 (Actual Total 9 0 0% 0%

Fall. Conditional) 3 (Pot. Tota! 39 14 36% 30%

Fall./ Degradation) 4 (Act. Partial 22 5 23% 11%

Failure) 5 (Pot. Partial 14 7 50% 15%

Fall./ Degradation) 6 (Failure of 63 20 32% 44%

Another System)

Total: 147 44 31% 100%

Table C shows that GL 89-13 efforts were more effective in identifying deficiencies related to biofouling and design than deficiencies of the other types.

Additionally this breakdown shows that approximately a third of the Safety Significance category LERs identified may have been identified as a result of GL 89-13 efforts.

The Table C data were also evaluated for its effects on the trends identified in

, the Cause categories in the previous section. Slightly increasing trends were L1 28 l

1

identified for these LERs in Cause Categories C, E, and F. Evaluation of LER data excluding the LERs that appeared to have been identified by GL 89-13 efforts resulted in no trends for any of the Cause categories. Therefore, it appears that the trends identified in the previous section were strongly influenced by GL 89-13 efforts.

Table D shows that GL 89-13 played an important role in identifying LERs in Safety Significance Categories 3,5, and 6. As for Safety Significance Categories 2 and 4, the LERs of these two categories describe actual failures and; therefore, GL 89-13 inspections are not expected to have greatly contributed to the numbers of LERs in these categories.

An evaluation was also performed to assess the effects of GL 89-13 on the generation of LERs in each of the Safety Significance Categories. A slightly increasing trend was identified for Safety Significance Category 3 and a strong increasing trend was identified for Safety Significance Category 5, Evaluation of LER data excluding the LERs that appeared to have been identified by GL 89-13 efforts in Table D resulted in no trend for the LERs in Category 3 and a strong increasing trend for LERs in Category 5. This shows that the trend in Category 3 was likely a result of efforts related to GL 89-13. Approxirrately half of the increase in Safety Significance Category 5 was due to GL 89-13 events. There was no trend for the total number of Safety Significant category LERs (i.e., LERs in Safety Significance Categories 2 through 6) when excluding GL 89-13 related LERs. This also indicates that the previously identified increasing trend resulted from LERs identified by GL 89-13 efforts.

4.3 Assessment of SWS ASP Data (1986 through 1994)

There have been 17 SWS related ASP events (out of a total of 219 pwcursor occurrences of all kinds or approximately 8%) for the time period 1986 through 1994. These precursor events are listed in Appendix A, Table 7. All 17 events were captured in the Safety Significance categories in this study. A breakdown of the 17 events into Safety Significance categories placed one event in Category 2, seven events in Category 3, one event in Category 4, and eight events in Category 6. The majority (15 of the 17) of these ASP SWS events involved the loss of a specific support system heat exchanger, used for AFW or RHR (Safety Significance Category 6) or involved conditions with a potential for total failure of the SWS, usually the SWS pumps (Safety Significance Category 3). None of these ASP events showed evidence of commonality among the SWS contributors.

The conditional core damage probability (CCDP) associated with these events ranged from 1.3E-6 to 4.8E-4 (Table 7) and were consistent with the SWS contributions to core damage frequency from IPEs. Two plants (Catawba 1 and

2) had CCDPs in the higher range (E-4), coupled with a high percentage of Core 29

Damage Frequency (CDF) attributable to SWS failure in IPE analyses (47% -

see, Appendix A, Table 8). However, neither of these events resulted in an actual total or partialloss of the SWS. One of these events involved a degraded interfacing system (AFW at Catawba 2), while the other involved a potential unavailability of the total SWS during a dual unit loss-of-offsite power (LOOP) for Catawba 1 and 2.

A breakdown of the events into Cause categories placed two events in Category B, one event in Category C, one event in Category D, five events in Category E, and eight events in Category F. This shows that approximately 76% (13 of the

17) were of the non-mechanistic type (Categories E & F).

4.4 Assessment of SWS IPE Data y

Table 8 in Appendix A provides a licting of U.S. nuclear power plants and the e contribution of SWS related initiators to each plant's overall core damage frequency. Figures 11 and 12 provide plots of these percent contributions vs.

the plant commercial operating dates for BWR and PWR plants respectively. For BWR planis, fractions of core damage attributable to SWS are nearly flat with regard to commercial op stion start dates. The slightly increasing trend of BWR IPEs is largely due to an outlier data point for the Perry 1 plant. Without the Perry 1 data point, the BWR population curve is nearly flat. For PWR plants, the figures show a decreasing trend for the fraction of cote damage attributable to SWS as a function of plant commercial operation start dates. An evaluation of this plot excluding the data from Turkey Point 3 and 4, and Catawba 1 and 2 (the four points that appear to be distinctly higher than the rest) still showed a slight decreasing trend in addition, PWR plants have about twice the contribution to core damage frequency due to loss of ESW, CCW, or UHS initiators than BWR plants. On average, PWR p' ant IPEs attribute about 13% of their core damage to SWS initiators, whereas BWR plant IPEs attribute about 7% of their core damage to SWS initiators. There was no statistically significant trend in the '

relative contribution to CDF among BWRs or PWPs with respect to plant age.

30 ,

o Figure 11 IPE Fraction of Total CDF Due to SWS for BWR IPEs so

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1 5 FINDINGS, CONCLUSIONS, AND RECOMMENDATIONS

5.1 Findings

The major findings relating to the review of the SWS operating experience are:

(1) There were no failures of SWS that resulted in an actual loss of core cooling capability. The few short term losses of SWS (less than 2% of the 579 reported SWS events) that had an impact on core cooling capability were identified and recovered promptly. These involved four "at power" events and five events during shutdown operations. For the "at power" events, the recovery time was usually less than 30 minutes.2 Most of the "at power" events involved failure of one train while the other redundant train of SWS or emergency power was out-of-service for maintenance or testing. Several of the shutdown events required a longer recovery time (approximately four hours). However, recovery occurred without any significant impact on core cooling or damage to equipment served by s the SWS.

(2) The analysis of the safety significance of the events indicated that e Events in which one train of SWS was actually lost accounted for a litt%

less than 4% of the 579 reported SWS events. These usually involved failure of one SWS pump, thus affecting redundant availability of service water to dependent ESF systems (e.g., EDGs, rces),

• The majority of SWS events involved Actualloss of a specific support system component (e.g., EDG heat exchanger due to debris, silt, or valve misalignment) or Conditions with the potential for causing loss of one or more SWS trains due to design or procedural deficiencies (e.g., (a) all service l

water pun.ps performance was degraded below design due to .

design deficiencies and f.) improper testing sequence resulted in securing the only operable service water pump prior to completing testing on the pump being returned to service).

(3) Approximately 12% (17 of 147) of the Safety Significant SWS events were also identified ac precursor events in the ASP program. The number of ASP events relating to SWS problems is about 8% of the total 219 ASP events. The majority of these ASP SWS events involved the loss of a specific support system heat

+

exchanger, used for AFW or RHR (Safety Significance Category 6) or involved conditions with a potential for total failure of the SWS, usually the SWS pumps (Safety Significance Category 3). The conditional core damage probabmies 2

During these events preferred (offsite) power was available. However, had there been a loss of offsite power, service water would have been required within about 15 minutes to provide cooling to emergency diesel generators.

32

I associated with these ASP events ranged from 1.3E-6 to 4.8E-4. These CCDP ranges are consistent with the contribution of SWS related initiators to the CDFs in IPEs for the population of plants.

(4) No trend was detected in the annual rate of all SWS LERs (579) over the period 1986-1995. However, the number of Safety Significant SWS LERs (Category 2-

6) increased over the 1986 through 1995 period. Licensee programs in response to GL 89-13 efforts played a significant role in identifying safety significant SWS LERa, Of the 147 Safety Significant SWS LERs,46 appear to have been identified as a result of efforts related to GL 89-13. This study found no trend in the number of Safety Significant LERs when these 46 events related to GL 89-13 are removed from the database.

(5) A SWSOPl review was performed to see if new safety significant items were found in the SWSOPIs that were not in operating experience, and to see if inspection findings were consistent with operating experience Six LERs were generated as a result of SWSOPl findings including one Safet, Significance Category 6 LER (specific support system heat exchanger) and five LERs that

, were not classified in the Safety Significance categories. The SWSOPIs were p ,,, rily reviews of the design bases and licensee compliance with regulatory quiremente for processes to monitor and verify continued applicability of the design bases. Program and process reviews formed the bulk of the inspection instructions and the findings reflect issues predominantly related to program and p ..ess deficiencies rather than operational failures or degradations.

(6) The IPEs indicate the percentage of CDF attributable to SWS failure is about 13% for PWR plants and 7% for BWR plants. There was no statistically significant trend (increase or decrease) in the relative contribution to CDF among BWRs or PWRs with respect to plant age. This indicated that the data are insufficle 't to conclude that " aging" effects are a significant contributor to the IPE results.

5.2 Conclusions Licensee activities in response to GL 89-13 appear to have been successful in identifying safety significant programmatic and design related issues affer., ting SWS performance. Licensee GL 89-13 efforts primarily identified problems of the Ychntial Failure / Degradation" type rather than problems of the " Actual Failure" type. This is consistent with the intent of one of the GL 89-13 requirements to veF#y design adequacies and maintenance programs. This is indicative of a substantial effort to identify and correct design and maintenance issues which might become operational problems if left unattended.

Data for this review of SWS operating experience were gathered during the period of GL 89-13 formulation and implemenMtion. Since GL 89-13 activities were completed 33

relatively late in the period, it is not possible to assess the overall impact of GL 89-13 on SWS perfomiance. However, the frequency and nature of the SWS events reported supports the risk implications of SWS performance indicated in IPE and ASP analyses.

These analyses indicate that for the general population of plants the SWS performance was a measurable, but not dominant, contributor to risk. Plant-specific risk contributions can vary.

5.3 Recommendations .

AEOD should continue to monitor the overall industry experience as indicated by LERs and the additional reliability data that will become available via the industry's Equipment Performance information and Exchange (EPIX) system. Trending should be updated with a minimum of two additional years of experience to determine if safety significant improvements in SWS performance have actually been achieved and to assure that new or unidentified SWS safety concerns are not present. The purpose of this work will be to determine if the operating experience indicates safety significant improvement in performance as SWS actions in response to GL 89-13 are completed NRR should evaluate the effectiveness of future SWS inspections (SWSOPIs or other inspections of SWS performance)in light of the risk significance of the operating experience discussed in this report. Future inspection activities should be more focused on the generic risk insights in this study with respect to safety significant SWS performance with consideration of plant-specific PRA results and relevant operating experience.

S e

6 REFERENCES

1. NUREC-1275, Vol. 3, " Operating Experience Feedback Report - Service Water Systerr. Failures and Degradations," November 1988 (AEOD).

I

2. NRC Generic Letter 89-13, " Service Water System Problems Affecting Safety-Related Equipment," July 18,1989.

3. NRC Generic Letter 89-13, Supplement 1, " Service Water System Problems Affecting Safety Related Equipment," April 4,1990.

4. NRC Memorandum from Ashok C. Thadani," Resolution of Service Water System Problems at Commercial Nuclear Power Plants," September 11,1991.

5. NRC Memorandum from Ashok C. Thadani to Thomas M. Novak," Trending of Service Water System Problems," December 10,1991.

6. AEOD/S93-03, "Special Study, Operating Experience Feedback - Service Water System Failures and Degradations," April 1993.

7. NRC Generic Letter 88-20," Individual Plant Examination for Severe Accident Vulnerabilities - 10 CFR 50.54(f)," November _23,1988.

8. NRC Memorandum from William T. Russell, " Temporary Instruction (TI) 2515/118 Service Water System Operational Performance inspection (SWSOPI)," January 7,1993.

9. NUREG/CR-4674," Precursors to Potential Severe Core Damage Accidents:

1994 - A Status Report," Vol. 21, December 1995.

10. NRC Information Notice No. 90-26, " Inadequate Flow of Essential Service Water to Room Coolers and Heat Exchangers for Engineered Safety-Feature Systems," April 24,1990.

11. NRC Memorandum from R. Lee Spessard, to Charles E. Rossi, et al. "SWSOPl Performance Effectiveness Review," October 18,1994.

12. NRC Memorandum from Charles E. Rossi, to Lee Spessard, "AEOD Comments on NRR Approach to Service Water System Operationa1 Performance inspection (SWSOPI) Program Review," September 20,1994.

13. NRC Information Noticc No. 90-39, "Recent Problems with Service Water Systems," June 1,1990.

35

e s

0 4

'l SERVICE WATER SYSTEM FAILURES AND DEGRADATIONS APPENDIX A - TABLES

APPENDIX A Table 1. SWS Related LERs from 1/1/86 to 12/31/95. LERS are sorted by: 1. Significance a

Category (SC),2. Cause Category (CC), and 3. LER REFERENCE Number

1. ' D8T PLANT RA88E REFE8ENCE DATE - TR CD8tPDENT ' CC SC 1 ASP SWP L C. C. O. RATI ~ T u ' A i ' til1L COM - REG PIE i 1 280 Surryl l280t94012 5150 80 iP wes 8 42  ; ;72 ,72 !788 ;P 'W ,SW iVEP i3d #2 2 !3t1 j$elen2 f 311l8S001 ;1/185 ~

89 iP wry C l2 i iB0 81 (1115 iP lW iUX iP EG ;3 il '

3 1237;0=seen2 l237,8S028 .9 % 89 '89 . Pwee 'D !2 i 170 !70 !794 l8 jG iSL iCWE 4g ;3 4 1250 ;iwket Pt3 l2548S 001 !1/1489 39 i Porsemel if ;2 j72 l72 I693 PW .BX ;FPL :3b 4  ! ;2 1 g i334 instene2  !!36!92 012 ; 716!9 2 192 :Pecedire .E '2 i i 175 !75 1870 .P iC ,8X NNE !3bt il P 8 400 ;5heere> hems 640$88,012 ;E1188 188 Proceene E 2 i '87 ,87 900 .P iW ES { CPL ;3 ;2 3 '

7 I458 her8 erd 1 i45t8S020 '4/19lt9 ;89 Pn,ceene E '2 85 86 '936 ;8 (G ' SW lGSU lSh

• 1

4 8 5247 Wen Pt2 :247I91 009 18 10/93 93 iPug if ,2 i i73 l74 ;I73

• lP iw IUE iCEC i3 11 g i26910censel ;26t%011 i1W1/86 Ils l Deep lF !2 l1 1 j73 l73 ,887 ir !B iUX 10PC 13b l2 10 1213 jHeddam hsch t ;213!91 017 8l23!91 191 :Stener iA i3 i

!67 i6S ,580 ;P lW ;SW iCYA j3 il  !

11 l213 iMedemmhed! l213'92 015 612$92 i32 iStimmer A ;3 j i67 '68 (580 il P lW iSW lCYA {3 1 12 1247 lineen Pt2 s247l8SO11 SII'83 189 ;$trenar iA l3 l j ;73 l74 i t'3 lP !W IUE : CEC 13 'l i 131213 !Heddam bcki l213/95019 11W11!95 l95 :Strainem it ;3 67 68 1580 3P lW iSW ;CT4 i3 ;l i 14 l219 i0, ster Cask '2191 % 010 l7l5J94 194 !heet Eschever 18 !3 ,

i 69 i69 i450 ll iG BR lJCP 14g 11 Il l219 i0yster treek i21W94015 !4lS"B4 iS4 ! Flow Element 3 !3 i69 l69 j650 lB iG BR iJCP j4g il 18 j245 Miesteral 1245/88-007 !$8:88 8 ;3 188 l6trumer l l70 (71 j660 il lG !EX JNNE i4g il 17 l280 ISunyt :280/95 006 '8l22l95 !95 'Pwres 8 '3 i i72 172 I788 ;P lW jSW MP 13d 12 18 1302 ICrystal Rn=3 i30tR013 !$13/94 ip4 'Neet bihange 18 !3  ! i77 477 it25 !P 18 IGX FPC i3b l2 Ig (213 p hock 1 l213l31015 18116/93 iS3 iFdter Houent it ;3 '

167 68 ;580 !P lW '5W ;CYA 13 i il 20 ;245 (Mailstenel ;245l92 026 110i2l92 :92 'Poe 'C  !

170 (71 <B {G iEX 1NNE 4g 13 4 i G60  !! t 21 (245 Wstenel !245i91023 i10f15 9J !93 Pos :C ,3 , j70 '71 !660 i8 G EX kNE +4g Il 22 l213 :Heesen heckl l213l91017 !l1/1!93 ;93 'Stemner 0 13  ; ~67 68 1580 ;P lw lSW iCYA 3 11 i

23 (370 lMcGam2 i370ts?-017 9'4 87 i87 ;Ht beh 0r 0 .3 l3 183 84 11180 .P 'W 10P iDPC i3c .2 l 24 i245 !Wstenel :24SS4016 11@4l90 105 .Persemel E 1 '

l70 171 1660 B !G E) NNE '4e 11 la 23 j250 lTwkey Pt3 ;25&tS006 ' 3l12.89 ;89 .Persarmai if 3 i !72 !72

! 1693 iP !W lBX 4 FPL l3b !2 2C l260 !8mwru ferry 2 ;260l85 013 4/S 89 189 :Pmcedure ;3 i74 i75 ,8 G !UX iTVA '4s 27 !368 l A&arue:2 {368 91-012 4'16l91 91 .Pmcodwo

'E 13 114 ,78 (1065

,912

2 *

\

E 180 .P < C .BX l APL in 4 P 23 ;3691McGwm1 36 2 91 014 Il044'91 191 Persemel ;E ;3 !81 81 (1150 P iW iUX 10PC 13e '2

• 2g !382 lwaterters 3 38191006 ;10/1593 lS3 ' Procedure ;E .3  ! iS5 '85 11104 iP iC LEX iLPL j2s =4 ;y 30 '413 !Catswbel '413.91 002 .2l25;93 it? Paceens E .3 117 ! 185 ;85 ;1145 ;P !W l0P 10PC i3c l2 il 31 482 ;welf Censk 482l91014 Sil,90 i3S Pmceene ;85 185

'E i3 i !1170 lP !W ;BX :KGE 13b i4 'l 32,443!Canswesi '48187-018 tilSit7 87 Persomst ;E 13 l I64 iS4 l l1171 lP lW 18X IUEC 13 i3 P 33 !245 iMdistenel ;245!92 014 ,3l12lS2 192 lDeer 4 F l3 i l 170 !71 l660 i t lG iEX [NNE l4g !1 l

255/%C36 .86 iDemy 34 l255 lPahendre 9/30/86 IF 13 l l 171 l71 1805 !P lC 8X lCPC lh 13 1 351255

P LL. 1255/86 021 (1114/88 188 'Deae :F l3 '7 l 171 171 {805 ;P IC 18X lCPC l& ;3 l 38 l261 iRehemen2 1281!92 015 i7l31192 lS2 ISeers (F 13 l l l70 i?1 1700 iP lW lEX iCPL 13e ;2 i 37 !271 lVemumt fases (271! % 002 I2!$94 M Deep if !3 I I j72 j72 l514 !8 iG lEX lYYC {4g l1 1

38 1771 IVenumt Yemee l271t%013 110r13/94 i94 'Pye I72 !72 iS14 8 lG iEX iVYC jeg

.F  ! l it i 391295 ;Zioni 129S85019 !10f25Its ;88 ;Demy if 13 j9 i j73 i73 (1040 P !W ;3L ICWE la 13 l 40 !298 lComper ;298/91 001 ;2l2SS3 !93 Deep !F i3 i {74 j74 l778 8 iG iBR pdPP l4g j4 l 41 !?98 !Ceaser !298l94028 111!1l94 194 10eep F l3 ! I I74 174 l778 (8 !G lBR jNPP ;4g i4 i 42 j302 !Cryste Rner3 i3C2l94018 l11l211/90 ;90 0eep 1 !F i3 i l 177 177 j825 [P i8 IGX [FPC l& 12 l 43l209iMensYuese (30$%003 l2 22!94 194 :Dene IF 13 ! ( 172 ;72 ;825 jP lC lSW lMYA i3 il i 44 1313 l A&sueni !313ttS023 1S/12189 it9 Deep if 13 ilo 1 l74 ;74 1850 jr 18 ;BA jAPt la !4 i 45 l336 {Wstene2 l336/15010 111iT19 iS9 lSmenic lF l3 l l l75 !75 1870 (P it itX f80dE l&f il  !

481387 P -- _1 f3877%008 ! 3 31!94 194 lSannic !F 13 l l {82 183 l1065 18 IG j&X l ppt l5g 11  !

47 ;400 'Shearetherns t40048 6 006 l2ltl81 i38 ! Deep iF i3 # I j87 187 :2 l900 lP {W !ES lCPt 13  !

481529 Pee Veres2 t 521%003 !6l13l95 195 !Ce&de Camector iF !3 l . 186 '86 l122' IP IC IBX LAPS th !5 49 l295 !Ft. Cadneuil 1219 % 003 !3454 .94 :Pwie :A i4 1 l l73 l74 l478 lP !C lGH 10PP l& 14 i 50 _l311 :Se6em2 ;311It&002 1111 388 !s8 !Puge IA :4 i >

itC 181 l1115 lP tw juX l PEG i3 11 l 51 '423 lWstene3 423l91019 ;7l2S91 iS1 tHt bcher '8 ;4 l is6 !86 l1154 lP iW ISW l80dE l3ef d i 52 1213 inedden bek t ?213r$4.002 l 2l12l94 i94 Poe i4 f !67 l68 il

't I l580 [P lW iSW ICTA 13 53 j750 jiskey Pt3 '4TZ7 88 188 lPysg

{ 25@8&OO7 lC ;4 l l 172 (72 j633 (P jW l5X lFPL l1 12 54 i211 !Swev2 ;281'86 006 i$i16/96 l86 iPoeg, !C i4 l i 173 l73 1788 lP lW ISW l YEP {3d _

12 1 55 1324 .Sammsck2 ;324'S2 0C8 l10I19hl: 152 IPse IC i4 l i i75 j75 i821 it IG IUE ICPt !5e (2 l A-1

)

APPENDIX A

• Tabb 1. SWS R2t:d LER3 frcm 1/1/86 to 12/31/95. LERS cre cert:d by: 1. Signifiernca Category (SC),2. Cause Category (CC), and 3. LER REFERENCE Nurnber .

1. - D8T PLANTG8af REFERENCE ' SATE ' VR CaMPOSSI  ;CC' SC ASP SWP ' L t. ' t_8. '- HATE : T' W A E WTIL Cesi - MS ~ PIE 5612M l8eewe Vese,1 l334'94 004 !5/8!M lM :Poe IC 14 '

I 176 176 l835 iP lW iSW !DLC i3d (1  !

57 I387 F 1 f 387l86 021 j ll24!86 l86 jPwies 4 lC l ;82 l83 l1065 18 16 j8X jPPL l58 11  !

$8 [416 jGrand GJf !414/94 003 l110/94 !94 iPwup IC l4 { ,82 i45 il250 i8 lG lBX iMPL 4 !2 i 59 je43 !&sebmit 1 443l91006 !4f1!93 iS3 iVelve IC i4 i i (90 (90 11200 {P [W jut (NHT [3g it  ;

60 l213 lHeddamlenckt j213'91004 illl2/93 l$3 l P '- if 14 i # il7 its ,580 iP iW iSW ICYA ;3 Il 1V g) 1780 Iswvyt 1294 86 031 l10l30/86 186 lPaceees lE ;4 l )

l72 172 {788 tPW ISW (VEF (3d g2 (230 iSwryl I2 h J280/8&O32 11134f36 !86 JPr.e e-. it to l l j72 l72 (788 ;P lW iSW lVEP 13d 12 je 83 !?93 lPdemn1 f293/95010 11113l95 i95 lPH- E I4 l l l72 l72 j655 j8 IG !8X j8EC jeg l1 ti 641336 (Mnetene2 g5 iM6 iDaveSessel 1336195 039 l10/10/95 195 IPacedme !E l4 i } l75 175 it70 lP iC iSX M 43bt [1  !!

l346!$7 011 it!6/87 l57 ipr e. ;E I4 i2

{77 l78 {906 lP [8 !81 lTEC l2e j3 a 66 l247 inneen Pt2 l247186015 j10l20/08 i48 iDesen IF i4 1 j73 l74 !873 ir iw IVE jCEC 13 11 i 67 h47 !lneen Pt2 f 247/95011 I4/14195 l95 !Reley & $atch [F I4 l 1 II3 I74 (II3 iP IW IUE fCIC 13 II I g8 l280 j$wryl l280/8S030 l7/181t3 iS9 IDesen [F I4 l i 172 l72 l788 lP iw SW IVEP 13d i2 j 69 I3e5 I'ssemeine 1305/95 008 112/8/95 195 I8 maker IF 14 ! l 174 j74 j$35 iP lW FP lWPS (2e j3 l i416l93003 l3l24/93 193 iDeep 70 l416 lGeend Edf {F }4 i l l82 it5 l1250 18 16 :8X (MPL (Sh 12 1 71 l245 lMestenet 1245/92 024 is/16192 192 pl she cil lA !$ i l70 l71 (660 jB is iEX issE t4 il i 72 !482 ! Watt Cseek 14821%0w5 '6/8/M IM !stener {A l5 i iS5 !85 j1170 lP iw 18X !KEE 13b +4 I 73 l280 lSwryl !290/94 003 1214/94 iM :Poe 'C  !$ i i j72 l72 l788 IP !W jSW :VEP (3d (2 i 74 I296 Ibden Pt3 j286/95024 l10I21/95 195 IValve '

c !$  ! l76 l75 j965 iP !W iUE iPNY i3 il I 75 l3M IBesse Vens,1

334/95010 I12/18195 l95 IEnsammen Jemts iC f5 l l76 j835 iP ,W ;SW l0LC l3d il l 76 i423 Meetens3 !423/91012 !815I9 3 !83 !Poe :D :5 ! ' .36 77 [251 [Twkey Pie

1. 86 11154 !P lW lSW 3NNE l3dl il i

251/96 001 !2l28l90 ISO IP. . lE .5 j l

l73 {73 1693 lP iW 18X !FPL 13b (2 t' 78 !261 lRahmeen 2 f261191000 it!5/93 l93 !Proceses it ;5 l i l70 !?! l700 jP IW iEX iCPL j3e 12 ,V 73 l277 iPesch Battem2 1277192 026 110/13!92 IS2 iP; e. IE .5 , '

l73 i74 l1065 l81G !BX IPEC i4 l1 lV 80 1282 !Pene leiendl l282h4 011 111118!94 IM iPwommel lE :5 i i I?3 173 !$30 ;P jW lFP IN5P (2e i3 iM S1 1282 l Pane lesendl !282/95001 11/25/95 195 iPorsemiel :E 15 l i 173 l73 !530 lP tW fFP lIlh 12e 13 :M 82 141218eeve Venev2 ;412194 003 !3;141H l94 !Pecedum IE .5 i l is7 it7 iB33 !P !W ;SW ;DLC j 3d l1 a 83 !499 l South Tesse2 1499/91010 .5/2Cl53 [93 (Pescedum ;E '5 i i ist itS l1250 !P lW !8X (HLP {& (4 lP 84 1482 IWeil tmek l482/95007 112!29/95 its ! Deep IF '5 1 (85 iS5 l1170 IP iW iB1 (KGE i3b je t 05 I213 IHeddampersti }213/90 032 l12l27790 190 ;Stroner ;A :8 ! '

il7 {58 j580 ;P {W iSW ICIA l3 l1 l 86 '213 jHeddam hedl 254 MedCineet l213/92 012 !4/25i92 l92 IFdtw lA {6 l l {57 ;68 j580 lP !W lSW iCYA 13 ft j 87 lA j6 l l254/92 027 110f9I92 (92 IHeat Exchuser I j71 j73 l789 18 16 iSL lCWE 14 l3 l 88 254 IQuad Cateel I254/94 010 l818794 (M istmner lA l6 ! l l71 l73 l789 [8 iG lSL ICWE l4 89 1253 IMaineene l3 283f92-016 l11/7192 jt2 l Check VLV lA 16 j 4 90 l265 jthead Cates 2

{ l70 l71 !545 18 lG l8X !8SP !g 13 265/12 007 IM4/92 l92 lCasaw IA 16 l l127 l72 l73 l789 iS IG lSL lCWE i4g {3 91 1265 lthead Cities 2 12851 % 003 11130/94 iM IReem ceaner IA 16 I l l72 j73 j789 18 16 ISL ICWE l4g l3 i 82 (200 lSwryl j 280186024 {8/13I56 i46 lStemner 83 l281 (Sevy2 lA iS I l l72 172 l798 lP !W !$W l YEP {3d l2 l 1281!92 003 13!2992 l92 iMest tsciuger (A j6 ! l 73 j73 j788 lP lW lSW IVIP i3d I2 4 94 l2M !8eeuw Vasevi l3Mi%001 l1/9/94 lM Iheet EzA-= IA !g ; l 76 l76 l835 IP lW j$W lDLC 13d 11 l 95 M8 IFedeyl l348/9G014 it/IIS6 jr' iHtbeher lA j6 l 250 lTakey Pt3 1

77 l77 1829 iP lW l33 ifC la 12 96 j250/96018 i4/16/86 iS6 lH1 befgr l8 16 l l l72 !T2 [693 (P lW j8X {FPL in {2 97 l250 !Teeev Pt3 {250I95003 13l9/95 I95 ihmet tes#wge, 18 is i { l72 j72 l693 iP jw jBX lFPL in i2 l 38 1261 j Rahmeert2 l261/SS019 l9I5/98 (88 lHi bcher '8 99 l230 lSweyl it l l }70 l71 l700 iP tW lEX l CPL 13e 12 i

{280/94 014 l10/23/90 90 lHt Ex Igr ;8 l6 j72 l72 l 788 lP !W lSW jYEP (3d (2 100 l280 ISwryl l280/92 009 1711 219 2 92 IStrumrS jB j6 l j72 l72 788 iP lW lSW IVEP l3d l2 101l290 ISweyl 102 j28710smes3 1280I55010 110I6/95 95 iheet Ezshausen l8 it i l72 172 788 lP lW ;ew IVEP l3d 12 j287/8S001 11/12789 J89 lHt Escfgr l8 l6 l l74 l74 887 lP {8 lUX (DPC l& l2 103l304 j2ien2 j3C4/12 004 17115/92 192 lHestEzahnquer 18 j$ l i73 l74 l1040 iP IW lSL ICWE la l3 104 j344 jTre a 344/86 029 19I16188 188 lHt hefgr !B 16 18 ) (75 76 l1130 lP (W [8X IPEC 13b 15 105l369 iMcGismi !B !8 j 369/87 031 l11125/87 [87 lHt hclier l l81 81 l1150 jP jW juX l0PC (3e 12 j 1061397 lWNP-2 l397/92-017 1518:92 l92 jheet batager {8 l6 l l 184 !S4 l1100 l8 lG jBR lWPP tes (5 l j41318S015 l3IW98 107 j413 lCeisueet l88 lVedve 18 l6 (4 l 185 185 11145 lP lW l0P IDPC 13e 12 l 108 !423 justetem3 jul10020 j6/14190 j90 lHt he#gr jB l6 l l l58 js6 1154 iP lW {SW {IsE (3df 11 l 109 l423 lanesiensa 14pI90023 j$t15t90 j90 lHt hamer l8 !S l l j86 186 1154 JP lW lSW {NNE l3df l1 l 110i423 Inheeten 3 i423!95011 !5/15f95 195 IHendrehager '8 186 j88

!8 l l l1154 lP lW ISW ll#E l3df 11 l A-2

APPENDIX A Tcble t SWS R: lated LER3 fr:m 1/1/86 to 12/31/95. LERS cre scrtid by: 1. Significinca Category (SC),2. Cause Category (CC), and 3. LER REFERENCE Number

1. ' DET PLAM AlmE - SSF88 tace - Bail " 78 C8mP0EST ~ CC SC ASP sWP ' L t. c. s. > RATE T 5 ' A E ' UTE7 CSNT- SES PfE 11112471been Pt2 I247!95014 15l18"15 195 %rm Denant Weld It !6 l  ! 173 174 }$73 P !W lUE fCEC (3 11 l 112 j272 iSeemi !272'8S 005 j1127/89 ist ,Pipr9 (C ;6 l i i?6 lU 1090 P IW ju1 iPEG 13 l1 1 113 pt1 isdem2 i311It&O15 !7!26188 88 Pipms !C 't i  ; it0 it) Il j

! 1115 P IW lUX : PEG l3 114 l311 LSe6am2 (311196M2 l12l2000 ,90 = Pipeg iC ;6 11 3 l ISO j81 11115 4P ;W !UX l PEG !3 il i 11g l388 p -- _2 :388l94006 j 5/29190 ;90 -Ht lsdgr lC i6 l l lM 185 l1065 @IG ;8X lPPL j5g (1 1

!85 186 11221 lP it iB1 iAPS j3b ;5 l

[95 IJeestWete Cir 't 116 l$28 lPwe Verest :528!95 005 14/7195 8 l l 117 l213 !Hedeem hedt 12? 3l90023 }10l27190 190 jHt Endier 10 l6 l j  !$7 i68 1580 .P !W lSW ;CYA l3 11  !

118 I369 ;McGeel 1369/86 024 19/12!t8 188 !Mt Esdge ;0 it 1 i 181 181 j1150 !P lW iU1 10PC 13e (2 l 119 f 370 lMcGem2 1370!sE011 $17188 188 IHt (segr 10 l6 l 1 l$3 j 94 j1180 iP IW iDP iDPC j3c l2 1 120 f 2U l Peed Bettem2  !!77!M008 ill3'M !94 IPeresanel ;E j6 l j [n 174 l1065 !4 (G l8X iPEC l4g il Il 1211289 jiWil 125tt3002 11129f93 193 iPorsennel IE it !!8 i 174 174 1819 lP i8 lG1 ;MEC 13b 11 ly 122 l295 lZient 129996001 !1112/86 !86 lPacces. E il j j !73 l73 l1MO lP !W ;SL ICWE 13b i3 h 123 I302 iCrystal Rsver3 !302l95022 110/18!95 l95 IPaconne fE !6 { l jU jU 1825 }P i8 lGX lFPC l3b 12 10 124 I309 ? Mans Vedas !3091 % 018 il214/M iN IPeroemd E is i i !72 j72 lt25 iP jC ;3W !MYA 13 11 lv 125l352 ilnnonckt !352l%003 l2!6/94 iS4 lPeressui !E it i i IM 196 l1055 it jG j8X PEC l5g it iv 126 j364 lFede 2 l364l91003 j4!16/91 l$1 lPersonial ;E [6 l l iS1 191 1829 iP iW !SS ;APC la (2 h 127 l369 lMcGe=1 i369'87 006 l3110 37 :87 lPaceene :E IC i l l81 ill j1150 lP lw !UX IOPC 13e l2 la 123 I440 lSheennHerns !400l % 003 l2l20I90 190 f Pacesse 'E j6 l l il7 it? l900 !P iW lES CPL l3 j2 l*

129l409 ILeCreens ;409I95 002 16/16/95 195 iPesennd !E !6 i j I67 !E3 l l IAC l I 13 IV 130!412 Besver Venc2 I412l95007 IIGI3I95 !95 Pacaens 'E lG i  ! il? !87 + 833 IP !W !SW !DLC ;3d +1 lv 131!413 Catem6el 413l95001 14t20iS5 195 !Pereennel !E ,g i j85 l85 l1145 lP jW IDP 10PC l34 12 :v 132:440 iPorryl 1440I8S O27 18/2S 89 189 :Peremend it 16 j i !86 l87 {1205 j8 jG iGI jGil ;5h l3 ja 133 f451 lChntant '461194 011 15/14l90 190 i Proceses 'E {4 {11 l iS7 587 1933 l8 lG iSL LCWE (Sh l3 la 134 j482 iWelf Camk {482!36016 '8/2S 88 !88 Persuma  !! 16 j i f t5 185 l1170 jP (W 181 IKGE IJb 14

• 135 !4821 Welt Cask 44821 % 006 l$ill/M IM :Persemini :E i6 i i 185 j85 l1170 jP jW ;81 [K6E 13b i4 l 136 f 245 !h68etenel 1245/ % 013 It28!M !M IDeep !F !6 I I j70 l71 1880 18 jG 111 il8IE jeg 11 l 137 l26910censel 1269"95 007 11 216195 195 Veive 7 !6 l  ! 173 l73 j887 ;P 18 !UX 10PC 13b !2 l 1381271 !Venennt isakse ;271191 012 !4/2391 !91 0 amp 3 iF :6 11 5 l i72 172 j514 :B IG I!X jVYC tog 1  !

1391215 iFt. Calhasit  !!8S94025 jW2$90 ;90 . Deme !F 't l12 j j73 j74 1478 :P IC lGH l0PP l3b 4  !

14013171Ca vert ChH1 !317f93005 ;6 30lS3 193 ;0 amp lF ;6 J l 174 j75 iM5 P lc l81 IBGE l3 i it i 1411321 lHetch l f 321792 003 l1121!92 ,92 ;0emy !F 16 l l i74 175 17U iB iG lS3 lGPC i4g l2 l 142 l34610evelseest !346186 007 134i88 Its ;0 amp iF j$ l5 i lU l78 {t06 !P i8 181 lTEC l2s l3 1 1431361 ISen 0nstro? 1361/95 014 18!13495 ISS Breaker 17 18 l I {82 l83 11070 lP lC 181 ISCE l3 15 l 144 l364 Fedey2 1364/86 011 l10f1516 186 10eny !F [6 l l iti l81 1829 lP lW l35 lAPC ja l2 l 145l389 McGo el i369I92 006 !4130/92 l92 l Deep if j$ t  ! l81 ill 1150 jP jW !UI DPC l3c 12 l 1441397 lWNP 2 l397!93031 111!9/93 193 iheet Eschsger !F j6 l l 84 iM 1100 it !G !8R WPP 64g 15 l 147 l440 IPerryl I440I%015 14l$M IM l Deep 'F j6 l l :86 it7 l1205 18 jG jGX lGB 15h l3 l 144 i213 lHeddom hsch) 1213/86 006 Ilf15it6 jl6 jVdves !A l l l i t7 j88 j580 IP lW !SW ICYA l3 l1 l 143i213 jheedenhedl 1213/91 016 l8/14/91 191 lPgung iA l l l67 168 1580 lP jW ISW lCYA i3 l l1 l 150 l213 lHed8mn 8*sd1 i213/91 018 19i20(91 l91 {Mt Eschgr {A j l l l67 j68 iS80 lP tw ;SW lCYA l3 l1 l 1511271 lVement Ysees ;271193 014 9/24/93 193 l Pipe !A j l l 172 172 1514 !8 lG iEX lVYC jeg 11 l 1521272 l Seism) 1272l91005 12lP'91 ;91 iHt Eschre lA j i l 178 (U l1090 IP lW JUI ! PEG l3 11 j 15312U jPesch8 tiem2 12n!94004 13t21190 190 jPiemg~ {A j i l 17J 174 l1065 18 l6 !BX lPEC jeg 11 1 154 2n iPesch 8stiem2 12nt9sO2s lSt13l90 190 iri,ms !A i 1 l Inj 11085 !B jG !81 !PEC og 11 i 155 2:0 Servi 12:0ts&O34 111117t96 ist istmeer lA l l j jn in j78s IP lW jSW VIP 3d 12 i 15612:0 Ser,1 i2sct870c2 !!!4!s? it7 !vde o tA I I l in n j7s8 !P lw !SW VIP ad 12 l 157l295 Inni ;295/94 007 1 212 719 0 690 iPqumg ,A l l l l73 73 11040 tP jW :SL CWE a 13 l isll312 iRende Seca l312l87 036 110fl9/87 187 j Pipeg lA { l  ! l74 l75 1918 !P IB l8X iSMU a l5 1 159 j324 ! Base.42 1324/53 005 1216t93 ;93 l Pipe j 175 j75 1821 it !G JUE l CPL I5g

!A j l2 l 1s0 l328 lSeene2 l32sisSO20 i4:22lts !st ;vsves !A j i i ill 182 1114 IP lW jux lIVA ;2:e !2 l 161 (333 lRt#etne (33T58005 5/2S 88 S3 iValsee 1A i  ; i i74 j75 1821 l8 lG lSW lPfF jeg II i ig2 ;333 iRt#etnd !331"86009 l10(21188 its jHt Escher IA ! l l 174 (75 ;821 l3 iG lSW lPNY jeg 11 l 1631333 IRt#etad IJ313S015 ] 911 878 9 j$9 lVdves {A j l l l74 l75 lt21 [8 lC lSW lPNY (4g il l 1s4l333!Rutetne 1333t94012 {44t90 190 ;Ht Esegr lA l l l l74 l75 1821 !B lG ISW lPNY 14g Il 1 165 i414 iCat=*=2 i414/90 006 jt21190 SCriang !A j i i 186 IB6 j1145 iP tw IDP ioPC 13c 12 i A-3

APPENDlX A .

Table 1. SWS Related LERs fr:m 1/1/86 to 12/31/95. LERS are s:rt:d by: 1. Significance Category (SC),2. Cause Category (CC), and o. LER REFERENCE Number ,

a est nasrenn asetenem enn en seerester - Sc - et aar - sur t t. t a man r s - a r eVu oss He en 1H!468 R' vee nsel 46610009 jtle H s u ! eves V ;A : 1 1 85 106 836 d lG :9W ;Gsu .h 4 l Ig71249 Ommena3 I24ke6024 iS%19 89 lPosys  !$ l i I 171 j71 l794 It iG !$L iCW1 i4e 13 1pg j2H lister Pt3 I?50lt? 020 l11111/96 87 lHt hefer 8 l t 4 172 i12 ;693 lP !W i&I lFPL l& il 1 Igg l269i0essel l26W87-004 13 21/07 j87 lHt hshy 8 l t l l73 i?) $8? ,P 'l !UX ,DPC !& l2 1 170 !269 i0esmet i26616 000 isllet its iPamis 8 i  ! I i?3 173 lt87 ;P ;B iU3 0PC ja 2 1 171 :200 ilwer1 280'96 030 f10/29/96 IN $Peng 8 i i  ! 172 (72 j798 ?iW !SW iVIP l3d j2 [

172 !200 !$wvVI 430/87-018 (7/26.7 187 ti==r 8 ! i i 172 !72 1788 ,P iW l8W lVfP i3d 12 173l287l0esus3 287/86-003 8!1F04 1 08 Pet hshy 8 l l i74 !?4 tH7 Il 18 LUX IDPC 'A 12 174 ;412 :Sme'er vehe,2 412/96 013 :4!27!$9 109 lHileefgr ,8 l l t 87 l87 $33 {P jW l3W lDLC l3d 11 l 17s (213 Hassen

! tenet (21 1 08 021 19C8 ist Pwme iC I i i !67 j68 :68) iP IW jfW jCYA i3 it i 178 l213 iheenen sendl l21190003 ir29'90 it0 ;Pipus lC i i i i$7 j b8 jHO ' :P iW !SW ICYA i3 l1  !

177l213 lhasenn ebd1 '212/91 014 17/17191 It) iPipig it I i i i$7 l68 ,500 jP W ISW iCYA l3 l1 j 178 1213 Iheneen land t 121kDE017 I4l10/96 IM iPoe Wew it j i i il? l68 ;MO lP lW 15W ittA l3 it i 179I219!0sterhs6 1210'92 014 !!!!W92 182 iPoe :C i t i iB9 [69 l050 !$ [G ;9A IKP +4e il I lH IM4 [G8*e i244'91 003 lW28'93 l93 jVWee 1 C  ;

j 89 j70 >470 j7 lW 161 lRGE 3e il i 181 245 ileiheisel 124W91021 j10/21EJ it3 l Pye 170 171

.C l 1 i 'HO !S !G lEX fd 4e 1 1 132 247 ibik Pt2 1247/87-011 N0$l7 j87 lPeipe IC l j j j73 jM l873 Pi jW iUE lCIC ja 11 i 183}M7Ih8e12 12E012 11/21!91 ill iPeng .C i j i 173 74 l873 ;P lW lUf lC(C f3 l1 1 its (271 Itement Veees it71/86017 iE3W89 i49 [VWees C i i i l72 72 ille !I iG .EX ffYC 4 il 1 1H 271 'Vement Veem j!7114 016 111l3W94 lte :Poe i i i 172 172 $14 44G 'EX lVYC W 11 4

106 27218esm1 .272/90 026 ;4/11190 ;90 iPipng it i  ! i l76 in l1990 l' {W (UX lPIC i3 l1 1 1871272 ilelemt ;27t91002 l1/17!91 191 ,Piug JC ! I i 174 177 1000 lP lW ;UX PEG i 3 il  !

18e 272 $seen1  !!?2!$2 022 !10/27!82 !92 Poe !C j l l l76 l77 ' ' l1000 !P jw tut jrfG l3 il I ige ?7l !Dunde Ceiyant if75/96029 i1419'88 j88 ;Posee 'C i i to :55 l1006 iP !W jul jPGI !3 il l 190 I277 . Pend lettem2 1277T86014 6/18/04 IM ;Pumg >C  ! i 73 i74 i1985 ;8 l6 j81 lPfC .4g il i 131 280 iJwest l28N93006 iWit93 !$3 :Pye ;C l l 72 172 j7C8 !P lW i3W IVfP3 12 i 192 2H (Ceepw l298!93014 :3/16!93 i43 IVWee .C l t

i j74 ;74 l778 8 lG SR IIPP i40 i :4 i 193 302 CrystW

&sw3 1302/86 014 i4 12/06 iH iP oug lC l j j l77 177 ;B25 lP 68 IGX !FPC lh J 1es 31118essm2 (311188 022 (1422l83 ISS !Pipmg !C l j i jB0 l81 1115 ;P !W lUX iPEG 13 il l 1H 311 ilesen2 l311190012 il2l20it0 90 iPaug lC l t l 500 it) 1115 iP lW tX lPf6 ja 11 l 1H 311,$eem2 13 1I91 003 itilkt1 91 lPvag ;C i l l  !$0 i81 11115 {P jW UX iPE7 3 11 197 313 i Ammumet j 313/9S001 h!2&10 l90 f Hilasher jC l l l 74 74 jl1 lP {S SX IAPL & 4 l IM 317 !Cesert C6HI !317t34017 il%90 190 jPgung jC l l l 74 75 ! Del lP jC SX 868 & 1 l 199 3M :6nsenscL2 1324195 015 iWE'80 188 !Pung it ! i ( l75 j75 l821 B lG UE ; CPL le 2 j 200 333 $t Poind 1333/94 825 l'f15/90 je0 jveses lC j j j74 j75 821 8 lG SW iPWY es l1 201 362 'Laundl l3l2/C&O34 t 2l$/90 !90 jVWee lC i i jH IN 1055 8 !G !X lPEC 9e il 202 364 Nupe Caeski j354/9405 12l27190 jp0 lPgme pl l 106 !ss 1967 it iG lSX jPEG 4e il 203 388 Aemes2 1364/04019 11111186 ISO iPoios id j  ! j l78 {SO 912 iP lC l$1 iPL & l4 res 1300 jAesses7 368/96 012 j6f26/09 l89 VWee jC l j  ! 178 l00 912 IP IC l8X ' L & je l 20$ ! 423 IA8sta=J ' i423/96012 je*90 I

190 VWees it I i ISG tes '1164 lP iw {$W IIBE as 11 l 2e6 {423 ileestan3 l423/91-000 l4*91 j91 Peng it j l86 l86 1154 jP iw !sW Isle l3m l1 l 2g7 j458 llbese ladi {454rt7-823 j1219rs? l57 Pong lC l l jf5 l96 [938 l8 lG l8W ~CSU It i4 l 200 joll llbwer Bedl j458/96011 13I1W89 l89 VWome jC j i ) l85 its 236 {I jG 15W G8U jh !4 {

fog j482 lWeH Cast je84r00 023 ,9/8/95 ist iPoug it  ! l !B5 jB5 1170 lP lW 18X jtGE la i4 i 210l498 jamsch fement !498/80020 j4/1tB8 iP9 IPweie JC I I 180 j88 -1250 jP W itX HLP la l l4 211 52s Pale feest l$28!94006 jlf21190 iso jvdves APS IA jc l l l {s5 its 1221 lP C iBX l5 t 212 213 Humenn issel 121W92-014 10/10/92 jt2 Feier l0 l i I j$7 !N 500 iP {W 18W CYA l3 l1 l 213 250 Ishey Pt3 1250/8& O24 jlI11186 jH Pwise lC l j72 72 FPL lh (

883 IP [W 15X 12 N1 Russman2 l2E1185000 j4/1W99 189 lVeves :D l 214  ! 170 71 700 lP W EX CPL i3e 12 l 218 272 j8esumi jf72l91011 iGlW93 j$3 jfsush Reek jo i I l76 l77 1050 lP W UX { PEG j3 1 {

216 282 lPume leedt 1252/67-007 il/10/6/ jt? jPumg l0 1 73 173 530 jP W I,FP IIBP i2e 3 { .

217 2npani l29stS7016 nt3W 7 j87 tveves iC j n in 1940 pW !st CW in 3 218 306 jaemomme l306/92-020 1111I92 l32 liessel Scumm ;D 535 lP jw lFP IWPS l3e 74 l74 3 tit n0 iaa 2 ,37et:7 022 112:2t:7 l87 !ni usny #0 83 je4 no0 ' !P jW 10P j0PC l3e 2 220 370 airG=m2

_ in0ts*012 inst, jH iVev.s j0 _

83 iH us0 lP ;W iOP iDet i3e 2 i A-4

e ' APPENblX A Tcbb 1. SWS r%lat:d LERs fr:m 1/1/86 to 12/31/95. LERS are s:rt:d by: 1. Signific:nce

. Category (SC),2. Cause Category (CC), and 3. LER REFERENCE Number

1. fl81 Pt&87 thall MPitiSCI DA11 VS - 208BP0587 CC SC ASP SWP L t. t. 0. RATI fE Af Il7R COW 1 814 221 412 Seesw Vehe,2 412'90 016 jl'2tI90 ?90  ! Pipng 0  ! i 'f7 87 '833 7 iW :SW 'DLC 13d 11 1 222121) lHammem hed) 211 85 014 il/11.18 ,88 ,Possens I ! '47 I 68 580 P ,W [8W .CYA ja 1 il s 223]213 C. heel 21391 012 4/11191 91 Peesemal I l $7 68

[ .540 >P !W :SW (CYA ja il P 224 !!!3 feedese ledl~ 1213M 012 14/28 94 !M Pece4we (  ! $7 63 $80 i P 'W lSW iCVA i3 (1 0

!?$ '212 lheddero ksel '213 95 002 'll?it$ 95 Priewei I , i 47 68 580 .P ,W d 'y ISW {CTA 13 226 l213 jHeddam tmd) i213'95 005 21095 Ill Pernemsi [ ! 67 68 l ;580 PW i*W iCTA la 11 IA 227 j219 Oyster Creek 219 87 004 11/12/87 17 Preemmi ( ;

2;9 jl19 !0rsic Cost ,219:85 01 i { 69 69 650 $$ BR lJCP I4s {1 P 6'22J88 88 i Presmui t i 6P !st 650 6 !G BR tJC* jos 11 P 223 }220 16ee Mas Pt1 :22605 028 9 10/96 88 L; e I i i i ~69 69 < $20 8 ;G lUR NMP los 11 P 230 ICO me Was Pt1 j22012 0C5 2/21192 if2 ,Peroemmi ( l , 69 El $20 l8 (G ;UX gNMP 4g .y 31 231i237 0=esen2 I237tt2 038 (10'2112 92 iPomemst i t l i 170 670 j7M ;B <G ;SL ,CWE jet 53 'O 232 l237 'Ornedm2  !!3711011 l3/3 93 ;t3 ;Persumul I !  ! I '70 i?0 PM ;8 iG [SL (CWI jeg il 1 233I24I M'6stwel i24S88 002 i11W88 f a8 iPorsommi i j ,70 i i 171 ,660 8 !G i[X ;NNE 4

!g il P 234 1245 Meetwel !24kS4 020 iM :Peceene 235! !43 Maries)

!$'27!94 I ! i  !?0 171 1660 86 [1 M 'es II 0

!245 M 021 !6794 ' 94 iProceen 't !

h249 l0meem3 i f 10 lit isso it IG 11 iNNE i4s il ;0

((49'92 004 ill22lf 2 92 'Poseen ( 1 l j71 171 (7M it iG !st !CWI ;4g (3 IO 23? i24910maami) 249 92 011 ifl24'92 ,92 ;Pwsermal i

E j71 71 j?M B IC lSL ;CWE 43 13 ,[

238 l249 0=eesi3 1249'M 0ll lL 494 '94 ,Poceen 'I '

171 #71 239 i250 ITwket Pt3 l

i?M l 'G iSL !CWI 49 !3 Il 25$90021 l10 tit'90 it0 'Pocesse .I j 172 '72 240 j25161eee, Pt4 j i ;683 .P 'W 1 81 jFPL IJb it "

251f87 004 M 17

sf ;Pweemal I i ! i !73 l73 !$93 P iW lBX FPL i 3b :2 P '

24t l251 pme,h4 :251!85 013 !1W2W89 It Pwnemsi i

,8  ! I 173 f 73 683 PW ;81 FPL i3b 12 P 242 j251]Tuesv h4 '251/91 003 6126!si 91 Psecedwo -f i?) 173 I l 693 i P W ;EX 'FPL (3b 12 a 243 l255 iPaksesse ;255'86 024 3 844'8 6 i88 .Persen si I i 171 ;71 ,805 l ,P {C 18 1 CPC l3b 13 9 244 l255 jPsheeses (255/88 005 ;&4 58 ist iProceen ( ! i l l71 i?1 805 !P iC EX 'CPC in :3 P '

245 I259 !&rs=ru For'11  !!5586 007 11/27!88 188 iPreemmi 't i i i i73 174 l1065 il !G iU1 (TVA i4g .2 248 j259 ' Lear terry) !25& 83 023 L'2419 h

89 Proceene E i e i 173 l74 i10p ;8 (G IU1 i tYA ,4s (2 P 24 7 259 ,$reurs iwr,1 l258'90016 1104!90 -89 itersemel i

E  ; !73 l?4 (1055, 8 jG iUX iTVA leg  !! 9 243 281 Reisas4n2 :261/87 029 l11l18!I7 87 Poceene .I I i 70 71 i/00 .P W (X ; CPL (3e i2 P 243;263 hantcene :26187 C24 !11f21'87 - 6. .Pwimmai ~(  !  ; ,70' !?1 345 8 ,6 $1 INSP reg p 3

1501263 =Mentcene 126182010 ;7l2512 !s2 :Peceane

' j263 Me3eene j26152 012 E i 83 [70 if1 !54 5 8 46 .8X 'GP l4g !3 it r IL24 32 it?

lPoseene E +

93 170 !71 l545 $ !G iSX NSP esi i3 a

-2%! j263 haceae ;26195001 !2l& 95

!95

!Pweemal -f ,  !

l70 171 . igI jNSP jeg  ;[

2s3 I265 }0ued timen2 !26W86 0:6 (545 lB {G . (3 10(2F84 !88 iPorsemai i l i i l?2 i73 1789 ,8 jG ISL iCWI i48 ;3 ja 254 j259 Demsel l26117 006 ,6l2,17 it? ;Persammi i 255j269 Oceael

.E l l iT3 173 [887 ;P ft IUX l0PC (3b j2 h 9

26&12 012 ;&2&12 l$2 ;Pwsomal

E l t i 173 673 (887 P it hft !DPC j3b 254 j271 Iemuut

• wese l2 ic /

l271!S8001 12/11188 188 Paceen ;f I h j j72 l72 l514 8 iG itX (VYC tes il p 257 l271 lVement isese 1271/86013 i1W5788 '88 iPorsemal 1E 1 l  !  !?2 !T2 [514 6 ,6 ![I VYC i4g il P 253 271 ive nant ivase 259 272 l5ahm1

[271/93 004 [7mS3 j83 jteceene It j i [2 l72 ilI4 it 'S iEX VYC 5l4 ' lt i l272/06008 I4!14!96 l86 i PaceAne l j i 250 j272 jSalemi l272194023 j7/2W90 l90 P=ceeno i l 176 177 l1090 iP [W UK Pf6 ja il [

jE i 261l272 ilaism) l272!91019 i4/2111 191 iPwesesi If i

! l I76 in fl090 P fW UI iPEG (C {1 ~[

2g2 275 itheme tenven) 176 {U l1090 P (W lUX iPEG l3 1 (1 I' l27L32030 112/1rt2 iS2 Personal 't i 1 i l84 it5 l1088 P iW {UK !PGE j3 ;l iv 263 2D iPesch Bettem2 i277ttn012 i44/90 l30 IP=2. ; -

El l lD 174 {1065 !B iG l81 jrtC og !1 t 234 j277 ; Peach tettes2 i277104 023 13/10/90 l90 , P=.Ae l ! l l l73 ?4 i (1065 8 iG l81 lPEC i43 Il P 2sg 290 lSunt) l28387 005 i4/ti4I it7 :P=4 ;  !! l l i 172 j72 l788 ;P lw iSW VIP 3d l2 p 266 280 lSwryl 2g7I 280 iswryl p*0/87 008 l3/2&%/ l87 ;Pweermal ft l l l 172 l72 j788 P iw iSW VEP 3d (2 P 1290/88 007 ;2T;4'88 ist ;Pweemmi II j l 1 l72 l72 l784 ,P lW {SW (VEP 3d (2 P 253 l230 'twev) !280t86020 GT2818 [88 lP u . ;E ! j

! j72 !72 (738 lP 'W ISW VIP !3d 12 P 269 j280 ;$wevl '280f88038  ;&'?tT8 j88 ;Pwasmai lE [ j 2701230 ;$wryl

( {72 172 i738 lP W ISW VIP 3d 12 h

!?80c96046 l12l31f71 ;84 iPwsommi ;E j j72 j72 {784 lP ;W ISW 2711280 ,$wril 1280itS 017 18l89 jtt iPwsommi J j

{

j l VEP 3d

{2 P 2n!!80 i8erry, j l72 j74 j788 gP jw ! W S VEP l3d j2 P

!280/8S O23 j 8/'W89 l83 iPoceene t , ( i 172 j72 j748 lP lw lSW VIP l3d (2 ja 173i2*0 lter 91 l280(94001 i A14!90 !90 'Poesene 274 j280 j$wr:1 it l j i (72 (72 j788 jP W j$W l VIP (3d 12 H pSOIS1005 ;4l13/91 ill iPessmal it l 275 I282 :Preas hemelt 6282/87-008 *E87 l l

{72 l72 1788 (P W l$w { VIP (3d {2 p 687 i P" !E i j i j73 j73 l130 iP W !FP ilCP l2s i3 p A-5 1

APPENDIX A Table 1. SW3 Relat:d LERs fr:m 1/1/86 ts 12/31/95. LERS are ccrtd by: 1. SigMficanco Category (SC),2. Cause Category (CC), and 3. LER REFERENCE Numher ,

a est eunranet avessett aan en comPemer se sc aer sur te. c.s. aan : t e A t m cert- su Pm 2741282 ;PensideW1 ,282l90003 13'2190 ISO Pressens l73 173 1530 ;P lW M lEP ;2e ;3

>I l { i i l' 2771282 (Pone eded1 '2tPD5 011 till 95 Pevement 't i l j 173 173 1530 iP lW lFP ilSP !2e 13 il 21B l?t2 lPoas 6stedt '282/95 012 9'10tl _ 19$ IPowen  :( l I i j73 I73 530 jP .W jFP .IEP {2e ;3 l 27p;28l jft Cahmuni :28996 017 lE'3489 i49 ;Possen ( i j j ,P lC IGN 10PP l&

l13 !?4 ,478 !4 p 230 tel lft Cahuel 20093003 jl!26Jt3 93 Possen 't I  !

l jn j74 4478 ;P jC l$N l0PP j& 14 }i 281 2N .bden Pi3 {296/92 009 Ef12/92 92 Presenf 't j l l }76 l76 jMS lP iw ;UE [PNV l3 11 't 282 2H lbeen Pt3 i206193 016 .4f27/93 l93 Pe ssoas i i i I i76 j76 {M4 .P !W jut PNY il 11 !v 283 2H bess Pt3 I2W83053 il2l2/93 {t) ;Pemsmui i;6 i?6 965 !P TW IUE ;PNY ja it t i i II W 234 287 Caenen)  !?Ih8T005 64$87 l67 iPossere it j j j [74 ;74 ist7 (P $ 101 ;0PC ja j2

• 285 287 i0sses3 ;2th87 007 i4d0/87 l37 Pwessui '1" ~ l l 174 i74 ilt? ;P !B iUI !DPC In if '

2H 293 IPiepunt 1293'91 002 !!!11/91 ist iPossen it l j j j72 j72 855 ;8 jG iBX ;MC jeg il p 287 FM !Zsal 1299 ,6 006 it!7!95 195 lPoemen it j i i IMO iP ;W j8L jCWI in l73 iT3 13  !!

238 2N ilowns fwev3 l2 Wet 007 s'2Fes ;I8 !Passen ,E j i  ! i?6 ;n IM5 t jG jUK lTVA jee 12 p t

tog !!M ltenes I298:36 000 tilhts (89 emesen ;t j i l {74 j74 770 {$ G BR {NPP jeg i4 p 200 j290 lCasse: I2W86009 l2/1h03 ist ,Possen ;74 j 7,

( l j lng lt G tR ller ;4g 4 s 291 298 1*'e='  !!98/93 026 j[ j i?4 j74 iT10 $8 jG ;tR iper 54g 6/1893 l93 lPreesens l ;4 ,1 282 290 itswer 2W'83 030 l7l8'93 it) {Possen ji l ;74 174 j770 it jG jlR lNPP i4g 1 l 4 il 293 2N fComer f2W94009 !$t2$lM IM IPessen it i i 174 i?4 inB ile lG iSR ;18 1 99 ;4 1 2M 2M lCoom 2W4030 110!!0'M H itemmeul j74 }74 l770 j$ lG iBR l0FF i4g M t ! l }4 295 l302 l Crystal hver3 i302196 030 ;Il%B9 its iPwessai ,t l j l in ln it2l ;P lt ;G1 jfPC in  !! h 2M {302 !Crvetal 4sw3 {302/90 017 (10/20/D0 iS0 ;Pomeeul it l i j jn jn IUS ir ;8 iG1 'f PC ;& l2 p 297 I302 ICrystal hoev3 1302!M 014 !IG:31t94 :M Pac * .r. 't i i 1 ;1? iT7 i&25 ;P 8 G1 iFPC lh ;2 0 298 I302 !Crvetal hom3 I302!95 024 l10f30It5 ;95 :Paressel lt I { T7 j77 ;t25 .P ,8  !GI ,FPC in  !! .M 299l30$iewsmus ;30966 014 Il2/21H ,86 iPws vet it j j74 ;74 l535 lP :W jfP (WP8 i2s l il p 200!308 Pene lsesul2 !30E!94 004 I12124M 64 iPweemmi t i i 174 (74 il20 it lW IFP IIAIP 12e 13 11 301l309 tessu toess ;3Cr83008 641Wl3 is3 jrmessne t l j i !72 ;72 l825 iP iC 13W 1NYA il 11 lv 302 i311 j&sism2 j' I311/06 001 l102l88 ill Pweemul I i i 60 ;81 {11tl ir jw iUX iPEG i3 ~ 11 303 all j5das2 I211 10 032 r 7:2190 9 Presmal

!0 .I t i i to {ti l1115 lP lW !UX iPEG !3 l1  !*

304 311 lssism2 I311194 013 II0i23:M M iPeasual lt 1 i  ! i80 ill l1115 iP !W iLX iPEG i3 it (v 305 313 l Aesuant ,313 4 007 i t'l'88 ~84 ;Pweemmi 't j i j 174 174 !850 iP ,8 l$1 M 't ja ;4 P

~

30s 313 Assess 1 ;313;t4 017 - 11d188 ile (Possene .I j j74 l74 (850 iP ;8 181 ~ht in (4 j' 307 313 Aesumel l313!tSC29 :8:25/09 j$9 iPossene :t je p ~~

l l74 l74 iS50 lP l$ !EX lAPL j& .

30s 313 AAmums) l31190007 !?!31190 ;90 iPnesene lt l j j74 74 ;s50 lP 'B fl1 jAPL ja j4 P 30J 318 Cae2 !31E't1005 644t91 !$1 iPwassuf it l l78 78 1100 {P W IAI l108E ~3: la l*

310 317 Cal's't ChH1 j 04 045 jP C !BX lSGI &

(317tB3007 i12l2F93 (93 lPnesess  !! I 75 Il 10 311 318 iCaisert CnH2 i31812 004 j ?d t'92 ;92 Passen n 1945 iP C !$1 $GI la it ' i l76 il 10 312l322i9mussen ilu16010 ildelte itt ;Perseas  !! l t IM l819 [8 G SW UL llg l1 i' '

4'24t88 !st

Pessense 313 325 j8assuel l32S98 013 lt I i 76 n it21 it G Ut CPL jlg {2 p 314 325 Itasussel 32995019 l10/12/95 l95 IPeareal I l l 75 n 321 lt G UE CPL ile ;2 iu 31$ 327 issonvahl 32h96029 j7411H its ;Possese it j t oo til 1144 iP W UX TVA j2se 12

• Sig 327 tSetsvuhl 327ISGM1 l934/96 iD6 lPomuuss ;f i 4 j81 1148 (P W UK {TVA (2oe !! '

317 327 Saeevakt 132h87008 ill2&fU it? jPossene it p i 600 31 1144 (P lW UX lTVA itse it til 327 Sesspel 327187 827 la!9ft? 187 IPsemese

!! j ( j ISO l11 1148 P jW UK fTVA !se {2 319 327 Seonvahl 32h87-051 ild2/t? it7 iPoseene it j j is0 61 1148 ;P (W UI jiVA toe ;2

• 220l327 Iseesteht 1327tBT085 j10(23'87 i3? ;Posesse  :( ! l 630 l41 l1144 lP !W UK .TVA I2se !!

• niju7ise.s,ei 3nis7 07 n0rver it7 iPws.eui 1 8 i j in ici jitse jr (W iUI nA 12 . ;2

• 2n n7 lss ,*i Inm002 v518 se jrmswo ;t i p:0 ici jii48 !P lW iU1 itiA l2s. :: '

In 327 !ss==v*1 j32hS6001 Unt90 90 iPo=*n !E i iso !*1 TvA j2,e it

• 114e !P lW lu1 324 327 Saeevehl ng n7 se ,ei j32712 028 I12/2212 It2 iPessmene

!! l l '80 ' t1 lies tr ;W UI TVA i2se i2 I 1327m030 12 2 irs 3 jl3; Pome-w !t j i 30 iti 114: ;P !W UI jnA ir. it i 326 327 Seoneshi }321M013 tl23tM iH lPanese It i l l00 [81 1148 lP jW lUX lTI A j2se 12 I nr 3n 'mPeme 1332.92 o02 imt2 il2 ;Psese. it i 174 n it2i to iG !sW im {4, n i

n. 333 smeewe i333rt2 Pn 14492 j 2 lPw.u-w it j 44 -75 itri is jG isW im t 4, ii i 329 3M 8=mw'esel 3W96018 12n tr80 i90{ Pens =* Jt j n.76 3 35 iP {W !sW lCtC 13e ii

• 230 33C .Basser Vseegt 3W91031 1118 4191 l$1 iPemusui #

/ l l 7t !7

't isW lDLC IN l1

• A-6 m .

m ._ . -

APPENDIX A Table 1. SWS R:lat:d LERs fr:m 1/1/86 t312/31/95. LERS are strt:d by: 1. Significance 1 0 Category (SC),2. Cause Category (CC), and 3. LER REFERENCE Number

1. 951 PLA87thWE 808600001 - Mit it - ttWPteff P.C SC Aar SWP L t. t. 8. Mit f8 Af Vft 0051 Att til 33113M Dessw Vehn1 1334/92 006 :4T92 92 Pneedwe it i >

l

{76 176 -835 P 'W ISW 0LC Ik it tv 3

232I2M bes tehnt ' j3M13 000 -4:23193 ,93 Pa .I 4

,76 i?4 .P 'W 1 1 B35 iM iDLC ik (1 y 333 ;3M jpeien! ,P eedwo 1316 96 001 :4?29 64 86 I ! I ild l7$ 170 (P C iBX Mt int 11 9 3M l3M .metere! ,336'48 H 1 11P:25'98 It ! u i i j75 < 75

, 4870 ;Pi t itX ftMI int il a 3Mf338imeie=2 !3Mll011 5689 B9 da I i i i !75 f75 870 iP it ~BX *t ih' l1 P 334 j336lMestool l3M194029 :114 10 90 femamel I j 175 in 337 i338 We8*e2 13M/90022 11/1610 M Pesmew I

! i

87) if t BX timt int il t

,  ! iM in 870 P iC BX l Nest jhl (1 a 33g 3M 'Esteet  !!3613012 $24'93 93 Posesse 'I 1

! i IM 175 ~170 .P iC BX !Imt iht 'l ,0 33913M #88 test 3M13 020 !10,4f93 il3 Peteens  !! + 4 i iM i7$ [870 .P iC BX IIME' Inf Il 'O MO I238 l444nes2 .t7t95 3Mf95 038 95 Preevel I I !M iM -870 ,P iC <&X NME !&t 'I lt M11334 Isomem Amel 133E17 010 ;tl1917 M2i330ilewmAmet

't? iPoseene it' f  ! j '78 iTS ;907 rP W rSW tVIP lk '2

(334l86 016 $13!t1 !BI < Pseedwo ,8 l '70 178 !907 ir !W j9W i VIP j3d l

2 P M3l338IseweAmet I234'88 024 11413'80 its ;Poseene  ;( j j {M ;78 '907 it :W {SW 'VEP ik (2 P M4 330 jeeme Amet j338'89 004 4/14:39 3 ts enseen, it  ; j i j73 itI j2 H Mgi338 tier $ Amm1 ;335.'I5 005

!907 7W ISW !YlP l3d 4/1419 ist iPoceen, It j i j ;73 j73 it07 ;P ;W l8W l VIP W .2 i*

343l330 ilweAmel  !!38b',16 t'26!tt l48 iPoreeuw '

il l l if8778 [907 iP [W l8% (VIP k il 4 M7i338(seereAmet kJ0007 L'23:90 :90 fPossene ( i l ;79 j73 .P tw ;3W iVEP jad l l907 ;2 {*

Mg ;338 linere Amel Y338 '90012 112/4'90 l90 ( ;

i Paconne j j iD07 Pi +W ISW iVIP i3d

{78 {73  !! P Mgl338 ilsert Ame) 7 31/91 020 1E31191 l91 Poseene i 1 i l 78 !?g 1 907 lP 'W iSW iVIP i3d 2 o W0l338!Iser$ Amet i33s t2 014 l't 92 iS2 !Pocedwo I i  !

178 i?8 !$07 ,P tw !8W lVEP i3d :2 't 351 338 '80e'* 4*e1 ;334 92 315 10:29 92 il2 Perceene 'I i l ,71 78 it07 P lW 18W !VEP 3d 4 2 ;V 352 iM1 dome! 341/85 031 117019 [89 ;Poseene f  ; I ill (C8 11053 ,8 iG iSL '0EC I4e 3 P <

353iM4 II"s'n M416 030 91710 88 iPweemW l '1130 t i

,W 4

i 175 176 iBX 'PGC jn ;5 P i

M4 M4 ilmeen M4 91014 4 't'91 391 , Posse e [ } l j 175 i?6 l1130 :P lW ;8X !PGC in il 9 355 lM4 ilmeen 344'82 001 1I1612 32 iPwes=W ;E , I j in 175 j1130 IP !W ISE iPGC j& :6 iu M6 f44 I0een loses 1 :M&'92 003 3'2312 :92 ;Poemene ( ! I i

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i 8 APPENDIX A Table 1. SWS Relat:d LERs from 1/1/86 to 12/31/95. LERS are scrt:d by: 1. Significanc3

, Category (SC), 2. Cause Category (CC), and 3. LER REFERENCE Number a out rLastanes sansees ann - en esmesest t.c at asp - sise t e.

l. a. nnn - r e a t o m essi na en 441483 Camenett 48312 012 419 92 l32 Pweseuf I i i eM M

! AUIC !3 l1171 (P IW .81 3 :v 442 4H lSerih iesent :498 88 020 !2/16'80 ita .Presoul I i ,

! 88 98 l1250 ,P lW :SX lHLP in 4 l*

443 '498 >Seeth iesasi 498 88 023 13'11/90 90 , Pere 6pe .I j i j ;81 l88 j1750 ,P ,W ;81 . HLP :n ,4 fa 444 4494 l Sert Toisel 498 W 010 !?!19W IM 'Poceers f I

{88 88 11250 IP ;WJK iHLP in I  !

4 1 tv 445 l4a3 ;&suth feses2 499 96 024 :l/2819 89 ;Preennel  :( i

! , ;tt 89 il250 ,P lV! ;8X lHLP lh 4 P

.4g 1528 Pale Vreel :528!91 003 ,21091 ill ,Posenes '

I i i  ;$5 88 (1221 ,P fC $1 }APS i3b fl P 4471213 INeemm heel ,i21 184 009 T5185 !98 Deep f i i ,

! 67 68 ;580 :P jW ISW iCYA l3  !)

i 44g j!!3 heesum heet 621316 015 1518 88 180 Deep F! j 67 l68 ;l80 't jw iSW lCYA l3 il l 449 I213 homemm hedi ;213,85 017 !8/10lt4 lll ;Dene :F i i 67 '60 f580 P iw jsw l Cia !3 it l 1 i 450 j213 heenem heel I

'21 184 022 112l18 st l18 <Dene ;F i i j

-57 l68 580 ;P W ISW 'CYA i3 (1 t all j213 iheesse leedl l21185014 it,4/89 189 iDeep ,F j i j 67 ,68 j580 lP lW ISW !CTA 3 i 11 1 452 '213 Ihee8mm heel i213l9D 001 $t90 ISO !D eep IF l i '67 :6F 580 lP lW ISW .CTA ;3 l 11 {

453 !!13 !heedsm hedl '213fM 021 !12!16/94 Ik (Deep 87 54 ;540 ,P !W !SW :CTA !;

'F i l i il l 454 {219 lDvetw Cmak 219!D6021 il2096 l ;H ;&eens :F j '

469 ;tt '650 8 iG iBR lJCP reg l il l 465 l220 flens hee P11 ;22291 004 $15/91 i ti l Deep 45s !!37 ;Dmenien2 F i  ! l 69 ill ft20 it iG IUX NWP '4g il

.237191 018 ~ B/27!s3 iS3 : Deep if i i 170 j70 17M 48 .G lSL iCWE +4e -3 1 457 i237 iDenomen2 i237t93011 l10/1/93 it3 Deep IF t i i

70 170 l7M $ iG

SL ICWI i4g ;3 468 l237 !Dessen2 '237f94014 'l'23% '94 ! Deep 't i I I ;70 i70 {7M ,8 G , EL .CWI :4g i3 1 459 I237 !Desden2 ;237?95 017 17f14795 95 ;Peetstwe tseis 'I j '

! j70 iTO !?M it lG iSL ,CWE tes 3 1 480 I245 II6#stenel !24W86005 (E27188 i8t idsep 170 i7)

F i i i 640 it if (I :NNE i4s ,1 i 481 I248 iMestanol !245193 014 ik7l30 190 , Deep 4F ,

l  ! 170 l71 660 8 ;G 211 NNE 4e I  !

452 i245 iMestsel [24W91002 i2!t 91 ill 'Oser i F l 170 171 '660 $ iG . [1 :NNE tes 1 443 i247 lheten Pt2 ,247't6 010 STtt 188 : Deep :F t +

l 173 j74 873 ;P :W ;UE ; Cit 3  !!  !

4641249 lDessen3 f 24513015 1 11193 193 . Der F , i !71 i71 ;7M l8 lG iSL ,CWE iog iJ i 465 l250 iTetev Pt3 i25488 025 (1813/98 184 , Deep if I l l ;72 i72 1893 :P jW :81 (FPL lh 12 i 46s l254 ) Quad Crimol 5254 56 024 T11/96 ,88 Seneret !71 ;73 1789 iB iG :SL F l l

'CWI I4s i3 i og7 :254 iDuma Citsel ;254 37 008 5167 87 Deep f 4

71 173 1 3 i7tt 8 iG SL iCWE i4s

3 ast 255 lPeliesess ;2509D012 ,7'5l90 ;90 Deep F t '

i?1 171 805 ,P jC :SX ;CPC !& l3 4691259 lBowu Fwry) i25t I6028 T31/98 188 .Seems J j 73 i?4 i (1065 it {G !UX iTVA .4g l2 i 4701259 iBrown ter,s j25485002 l2185 its tsanic '

F t  : :73 i?4 ll065 8 ;G jUX {TVA I4g , j 471 !259 8mmu Furil ;25585008 14'2089 89 , Deep ,F i i l 173 {74 ;1065 ;8 iG IUX (TVA 14e 12 1 472;259 ilmesu fwevi l25191005 ;4!12l91 191 lSeems F l l iT3 ;74 {1065 48 jG jUX iTVA 44e _ i2 {

4731241 Rehesen2 ;251r8T011 ltl197 it7 lSeous J j l l i10 i71 l700 ;P W iLX ; CPL 13e  !!

474 l261,W !241/96 009 ikirSO iDO iDeep ,F l 1 i (70 171 1700 IP W i LEX iCPL (3e l2 475 j263 ihrweste j25YtS022 { t'20l89 :89 ! Deep F j ,

j iTO 171 {$45 !$ {G ;81 .NSP !4g {3 47sl263iMensene ;2sr9: 01s siitti :s1 iDuep if i j j70 !71 lMS ,8 lG ,8x NSP i4s !3 477 I263 IMantasse j25191-018 3 8l2191 :91 iSases J l l !70 171 ,545 it iG [81 ISP 4e (3 473 }259 lCommel l2fN96002 12iT86 ;88 !$senc ,F 1 i { !73 i?3 .857 iP it lUX !DPC 13b it 473 !?69 I Demmel l26596012 l1W1086 iS$ !Demy i f )  ! l l73 (73 jf7 jP j$ lUI DPC 1h  !!

480 269 jDesual PsttS0tt 110/17t39 lal ;$esec IF l  ! j iT3 !73 887 iP (8 IUX .DPC 4  !!

431 26910censi l253.13004 14t34 (33 iDeep *F l l 1 !73 i73 1987 iP jB !UI (DPC {& l2 142}269 ft%sneel I2$m001 I2f21fB4 IM Seene IF l l l l73 I?3 iS87 IU1 iDPC in 4t31269 lDemmel 2fM004 (7l2094 IS4 . Deep 'F 1 l  !?3 173 ,887 lP f 8 12 {

! lP {$ lUI !DPC !& 2 4 4M }271 jVesment fotee 271l8S009 l4/2089 itt iDeep Fl l I j72 j72 ,514 it jG !EX {VYC tog (1 1 4851271 itement feeus 27P51018 11Br21/93 l$3 iDear J ! l j l72 172 ille il 16 EX lVYC l4g {1 l 486 it?1 IVanent Tseen 271!94 005 l3/30T94 !94 l Deep tF l l l72 j72 >lle ,8 lG IEX {VYC !4g it i 487 l272 issimii 272l94014 i4/1890 !90 . Deep lF j l 17s 177 jl090 ir !W !UI IPEG l3 11 l 48s j275 jumble t: 21 27W8&l32 15/2Ese jes l Deep !F l l l tM ,85 l1084 }P iw jUX !PGt l3 il l

4891277 IPene6 8ettem2 l2,119 189 1 Deep 3 277183 002 jf j t 173 174 11065 l8 lG !$1 jrtt tot 11 1 490 iit0 iSw'il lis488031 itillst ;88 Deep ;F l t !72 l72 j788 lP !W lSW lVtP (3d (2  !

491 l200 ;Sw'il { $t3/ll (290 TIS 021 !89 l Dump if l j l j72 l72 l784 }P lW jSW ltEP l3d 12 492 :251 lSw't? j281/84017 i7134 88 188 : Deep b l l 1 (73 i?3 i788 iP ;W ,8W (VIP 63d !2 {

413 {282 }Pseas ts6edi ' 1282!96 014 111/30f90 j90 Duep F

] i i73 j73 1530 [P W lFP IEP i2e la }

4g4 j282 jPenne lessW1 l25t92 005 13/26192 l$2 l Deep f i i j 73 j73 i530 }P W jff -ISP ,2e l3 495 i295 IFt Capuun) i22W91017 14!20f92 iS2 IDeep J j l 73 j74 14 78 jP lC IGH iOPP ja 4 A-9

APPENDIX A Table 1. SWS Relat:d LERs fr:m 1/1/86 t) 12/31/95. LERS are C rt:d by: 1. Significanco Category (SC),2. Cause Category (CC), and 3. LER REFERENCE Number

1. Deti PtAff GMBF, Rf F1hillC! DAT1- 74 CDasPDIEIFT CC CC Asr 8stP 1 C. C. S. RATI 7 11 A_t Ufit Ceart at8 Pit 496 i235 ft Coheet 12tS'94 007 :1E7/W N Sed Wetee ;F  !

' i ;73 174 f478 ;P 'C GH OPP lh :4  !

437 l190 Mm Pt3 1286?t2 010 '11/17!f2 82 jDeep f i 76 178 .96l P W lU( , PNV !3 11 l 4p4 !?88 see Pt3 296l83050 111/16/93 ,93 ; Deep 7 r  ! 83 j76 178 !165 P ,W ful PWY l3 j

1 opg l283 iPorent 293'87 009 ll0/2187 87 < Doop F , I i 127 iT2 566 l iG i8X Sit 4g 11 +

$00 [2 5 %ent j29k88 006 i3/25l88 88 . Deep f I I i j73 ;73 i1040 PW eSL 'CWI iA ;3 I 601 I295 iLent ;295/86008 'Il . Deep 6tti if l , l [73 ,H j1040 P in SL ,CWI i3b '3  !

602 l2951Le i 629kS2 000 i kl!92 :92 : Deep F l I j73 i T) l1040 :P iW iSL CWI i 3b ;3 I

$03 (296 ilmen fury) '296/86009 it'8/84 ts Deep I  ! l ;76 in j1065 8 iG IUX iTVA i4g if i

$041298 ,Cesser :298'f 2 005 S/11!92 if2 Deep f 1 l :14 374 l770 $ iG ISR IPP ;4g 4 '

505 !298 iteeper :298!32 011 6'2W92 92 , Deep I i 1 l74 j 74 ;8 IG j8R NPP tog l778 :4 l

$06 {302 CrystW Revel (302/07 020 l9.187 ;B7 iDeep 5 {  ! 1 j 77 ,77 itM ,P 8 iGI I FPC l3b I 4

{2 50; 1302 (Crysts Revoet 1302/88 002 11 tilt 9 itt ; Deep .F  ! l in IU i825 P 8 iGI 'FPC in '2 i 608 f 302 :Crystd fievm3 ill : Deep

!302/95 021 {D 4'95 ,F I j i iH f77 .825 P8 [GX iFPC in l2

$0g j304 ihen2 :304r90 015 111!27190 490 Seses f i i 173 l74 (1040 7 lW , $L lCWI lh 1 13 t 510 309 46mne 1 sees 308/93 018 84/83 l$3 ILeap i iT2 j 72 i .F j i it2l !P lC :SW WTA [3 it  !

gli 309 *eus temos 1303/93 019 ,9,28 33 '33 l Deep F j .P !C ISW WTA j.

l t

l72 j72 it?$ 1 512 {311 ite6em2 311/87 009 l11125tB7 87 ; Door

!f l 1 i 80 81 i1115 P lW 101 P!G ja 11 b13 l313 I A*eusel 313!I8 010 iS 25:36 = 88 l Deep jf I I { 174 174 '850 P ,8 81 APL in 4 514 l313 i A4enseel 313/88 022 !12l16/88 188 iDeep ;F l ,74 j74 850 P ;8 ,81 APL ik i4 '

lig 1313 E Ahmeest l313/90013 11E26'90 ,90 IDeep F i t i ?4 j74 1850 P8 i81 APL (3b r4 gig ;315 !Cadt ;315/98 014 :S!1k88 88 iDeep lF i in in (1930 .P 'W IAE +1Mt i3c 13

$17! 3lliced1 '315/94 008 E/1?90 90 Deep .F i i75 j75 l1030 .P W tAf 1Mi 3c 13 5181318 'Cedl '12/18'M tM Foo tem,

'315/94 013 ,F t i 75 l75 !1030 PW iAt ilWI 3c 3

$1,;317 (CWewt DN1 88 : Deep l317156013 )1219 Bt F i?4 175 H5 ,P 'C 8X 8GE >& ;I '

520:317 ICWrat hffl 31718 S 014 17l23 89 IS jDeep 5 i i l14 175 44 5 P iC ttX ilGI In j il i

$21 l317 'Calven C6ffl s317!85020 illl13'88 89 . Deep :F i l75 j75 845 P lC iSI SGE i3b il '

~

522 i317 CWved Ch'fl J17/BS 023 12/23'85 89 . Deep F i , ,74 i75 :845 P C l81 BGE i3b t1 1 5231317 CWeert C6H1 '317!95 003 '7133 95 95 . Deep :F f f l74 :75 !a45 iP ,C l8X '4GE ;& it  !

524 i321 ;Heid 1 1321152 013 '5:21!t2 iO2 IDeep F i ;74 475 !7U it iG ;SS jGPC 4g it i 525 i323 lDisa4 Canym2 i323'92 001 :2l14!32 92 l Deer F 1 i f $5 its l1119 lP iw 1U1 .PGI (3 il ,

!325i86016 ,6129 88 64 seenic

$2s l325 l8wamel ,F i l 178 lU l821 l l6 ;Ut ! CPL {lg i i

t i 527i325jtweendt I325/90 021 10,7190 l90 l Deep jF i i i 176 in ;821 j8 iG iUI l CPL ,5g l2 l g22 j327 iSeepsvehl ;327f87 037 ;7l28/87 {87 : Deep gMl327 lSamoveht

F l i i 80 t81 il148 lP iw (UI "iA ;2ee 12 i j 327187,045 i169/87 187 ;Dese 71 i ii i ISO t

{1148 iP lW iUI {TtA itse :2 {

530 j331 iDueu Amend l331l32 008 4l2/92 182 iDeep F i l 1 ;74 IM l$38 it it !81 {G !g4 ;3

$31 {331 ]Deens Ameld 331182 010 4 1/192 it2 iDeep ,5 j i 174 i75 $38 il jG iS1 (IEL :4g l #3 l

$32 {331 IDuere AmWd !331/93 011 111111lf3 93 iDeep 't i  ! j l74 i75 538 '8 lG iSE jE 14e l3 1 533l333 jhtrPeted 13WB2 004 Ill1Ft2 8? . Deep ;f l j j74 i75 js21 lJI jG j$W :PWY (4g it  !

534 1333 iFit#stad 133192 043 i t4!t2 l$2 iSeses IF j i l74 iTl il21 {5 lG iSW ;PWY I4s 11 I 535i333 iht:Peted {33192048 1111G'52 f 92 lSe it if i i I (74 175 l521 l8 jG ISW iPWY jeg I 11

$38 i334 itenver teneti I334!93007 l412T33 itOD isn if f i , i76 176 }835 jP :W !SW IDLC i3d l1 l

$37 ;338 itetetene2 l336/87 006 4/317 187 7 sop ;F t ) i 75 iTl it70 lP it iSI ;W lbf <1 j E33l336 jetastee2 !336%017 {1000/90 190 :Sese ;F i  ! } jM i75 j870 lP !C (81 lW {&f II l

$331336 itensteu2 l336lS3006 lT24!t3 ;93j$esec ;F i i { j75 lM lt70 lP ;C 81 l180( {3bf 11  !

540 j336 lnnsatset i336t94 014 ;502.H 'M 'Poe !F l i i Tl l75 j870 jP lC j8X ;M lhf 11 i 541 l3X lhemste=2 I236/95 003 !1130r15 A95 fventilation if ! i i 75 l75 l870 lP [C j81 iM l&t j1 i

$42 l336 !htestem) :33& % 001 !2/21195 !95 Itkop 'l f f i 175 l75 !870 P lC iBX ;W l&t l1 1

$43 j338 ;hlerth Areel 330/96 008 5/24'90 190 { Deep

! !F i i  ! l78 j 78 j907 P lW ISW iVEP 13d i l2 544 l341 jFene2 intl 86017 0 24'86 185 IDeep ;F '

t 85 lB8 j1033 it G ISL lDEC leg la l

545i344 jieute i344?S1015 4/12191 y IDeep l75 176 j1130 (P iW i81 ;PGC f2 5 i l f5 544 lM6 Develsenel j xtitS004 4/11f89 ;89 iD eep if { i j 6U j78 j906 IP l8 {BK l TIC j2e 13 u7 ;mt poie,i  ;>rt:0iB it:265: ist : Deep p i ;n in jt2s iP !W !ss wt ;n

! i l2 98 jus iFe.e,i ixaces 004 !sasin ;is Camp 7 ; j i in in ein iP :W p.s jAPC in 12 i ses 352 itmundl l352!sSO25 ;4!5ist ,8s ! Dome F l :84 l85 l 1055 il lG l8X iPEC {5e 1 l

550 353 its ndl l35186012 l2!1388 < 86 ; Deep IF i j :04 f 44 1055 i8 iG (8X iPEC iSAC 1 i A-10

. - _ _ . - - - - - - . - - - - - - . - . _ - - - - ~ . - - _

APPENDlX A Table 1. SWS R:lat:d LERs frem 1/1/86 t312/31/95. LERS are c:rt:d by: 1. Signifinnee Category (SC),2. Cause Category (CC), and 3. LER REFERENCE Number I'# BRT PLASTWWE 86P888804 - SAff C OGWPC EST SC = SC , ASP SW ' L t. t 8.6. GAft t 3 A F #ftL cost Me- Pet Hf i3M !Nene Csed] [354/96 O!! T12/84 lH l Deme ,H

!f I l l :H l1067 8 lG ,8X jPtG l4e {1 1 H21364 ! Mass Cmd1 j354 87 028 8/15tti jl7 l Deep if i 1 1 its les k?' g4 iG SX (PEG jeg j1 i 553 354 'Mase tendl j254%014 .8:17/90 It0 l Deep if j j 186 it (1067 f 8 !G SX 1PtG jeg ,1 i He .364 IMase Cod t  !)$4t94018 12/7tM !N lleveavig Semen if I i ;H Mi jl067 ,8 jG iBX jPtG iog 11 i 565 !3H! fe'I*t! !M4tl7 Oc2 9407 '87 IDomp jf l l l 91 ($1 :029 vt [W IS8 [APC { 3b i2 i i 6lg jMt j Anmess2 1368'88022 11/188 '88 l Deep j jf j l l78 l00 '912 jP it ,8X jAPL ja i 4 i 567 lM8 iAeness2 IM8!89 019 9'27t99 !$6 iDeep l j70 ;to it12 iBX { AP'. In i { l ,P ,C le i 663! Mt lA*mmes2 iM4ltS028 1110 2/09 itt iDeep .f j j l l10 t0 1912 ,P it :8X ;APL in i

to l Mp !M8 l Aemme2 l368/91015 912!$1 !ll iDene f l j j !78 180 !$12 ;P it itX ;APL ja i4 1 560 IMS Il88Gae=1 i369/tS007 i3/lW97 89 iSamme / l ,:llo l i 4 01 {81 .P ;W (UX iDPC 3: 12 1 661 i39t ilmeen ;396tt1009 ,$ttil? 87 ; Deep '

i if I I 82 IM ;900 ,7 lW ISX l8CC 3b j2 {

642 l395 Sumer i39htes 013 8!a>89 itsl8mmes it2 lM 6631397 lWIfP 2 j391106033 i140t96 ,86 jDeme if I

,f l l it00 ,7 :W IGX p1CC [3b (2 l l 4 i M ;M l1100 $ 'E ,8A WPP jet j$

$64 jH7 ;WifP 2 i397/91 021 El14'93 193 iDeep if 1 j j ,M jM lt100 '8 lG jM lWPP jeg !l 68t I400 itimmenHerse [400ft4003 j711tM IN IDeme if l j 1 C7 [87 ,900 jP 'W jf3 iCPL ja l2 I les p0 jetsu thee Pt2 I41&8&O26 112l29/88 l84 jDeep !f j l l '87 lB8 i1060 l8 iG lUX 181P Ilg il (

537l410 jlemm ines Pt2 410/46062 t/26/88 itt ; Deep if j j i jl? 88 l1000 18 iG lUX leer ile l1 l lag l410 itbu nde rt! 41W85003 i2/18/89 ist l Deme ,f  ! l t it? j88 61000 (8 G IUX lelP ing It i f,se joll iCetestel 141F57 038 lt30/47 it? ; Comp j if l { l85 i8t {1145 lP !W [DP iDPC ja  !! I 170 jet) iteneskel i41F85014 {10/20iB0 (89 iDeep j 7 l l ltl I8l l1145 lP !W !DP iDFC l3s 12 1 371j418[G#sedGdt i418/06 029 t/2006 '86 lDemp .f i 4 i !82 ISS [1250 8 is ,8X llePL jh i2 572 i 418 iG'=* Gd' '418 # 010 1719 90 itoiD==p f f I  ! (82 el ji2 0 8 iG ilX .uPL in ,2 p3 443 )sseb.ed i 44r32 015 ;rtist i4 t iDeme i f i i i ilo iso 11200 P ;W iut !ssHT ps it i 874 I4W l4, ent 454'94 001 i2/tt94 IM itseve f l i 18, l !s5 1120 .P {W ist iCWE in I3  !

$75I4ts 8.meimasi ;4ss w 0c1 :2!2/u iu Ivdes f I i i I:7 jee 1120 .P tW ist !CWE l3b is i 87s j46811bwerled) I45092 001 lF26182 iS2 l Deep 1l l l j85 les IBM :s it isw lG8U It je 1 in! 81 4 !Caetant 461186 006 pal:ss ,8s iD c 1 i I i ls; l7 1933 it iG iSL : cwt im is j 4 573 482 Wei' Nok I482l91002 tl23;31 Itt ICup ;f ! j

$7,14st isam fe=1

'll fel 11170 lP (W 181 .tCE 13b (4 l 498 s7 018 411724ts; is7 tDeme f 1 i ;ss ice i 11250 iP W ilX {HLP l3b 14 I Abbreviationi PIE e Fepare 3 Pee Chart Desagnators DKT e Plant Docket Number yR e Year of LER D = Doesgn M W Krewledge CC = Cause Casepory I e IST or Surveillance Test SC = SegnAcance Category M= nee, , or inshBaton Test ASP = Accusent Sequence Precursor Event Number (Table 7) P = Post ModAceton and Equipmert Test SWP e SWSOPI Finding Number (Table 9) V= Valve or Equipmerd Ahonment I C. = InM Daue of Cnhcal4 * = AnaW py premus study M 4 C w, of C O. = Commercial Operatng Date indwiuol event was not avanable The breakdown m Figure 3 RATE = Not Electncal Powee Output d his M was achaeved by combanng me dem presented in T = Plant Typ . P=PWR, B=BWR Figure 4 of the previous study wahlhe breakdown of the more N

• NS$5 Vendor **"I 'V*"35 0 882 to 1880 P'*8'"d in th'S

• A E = Architeetingineer b = Opereeng % Note that Regional Dosagnatons are provwed in accordance with me old NRC CONT = Coninenment Tm regional system (5 Rep.onal omicos). Former Region 5 was combene f wth REO = NRC Rogeon former F'ogeon 4 in 1993, melang up the current Region 4.

4 A-11

APPES IX A tam e 2 - Total sWS Faltures Canditlenal Cat m ory 2 (Sorted by Occurrence Date The 1992 throust 1995 events are marked by e)

(WITH PLANT At PaWrR)

Shearon Harris 1. 400/88 12. 05/13/88. On May 12, 1988, with power at 100%, the nonsafety portion of the Emergency Service Water (ESW) seat water system B failed to Isolate during surveillance testing and the system 1

)

was declared Inoperable. On May 13, *P88, an attempt was made to close the A seal water booster puip suction and discharge valves, but neither valvu fully closed, tendering the ESW A system inoperable and entered 1 i

Technical Specification (TS) 3.0.3. Prompt action to fully close the valves allowed exit from the TS 3.0.3 ten  ;

minutes later, without requiring a plant shutdown. The cause of the fatture was rwit specifically identified, but appeared to be be to an accunulation of debris f rom the raw take water.

Dresden 2. 237/89 28. 09/05/89. At 0910 hours0.0105 days <br />0.253 hours <br />0.0015 weeks <br />3.46255e-4 months <br />, with power at 99% for Unit 2 and power at 88% for Unit 3, in preparation for a Low Pressure Coolant Injection (LPCI) surveillance test, the Contaironent cooling Service Water (CCSV) pump 2A rm was attempted but resulted in flow cscillations. The cause was che to large enounts of floatiry debris in the intake canal, resulting in a lowered suction bay water level. The Unit 2 and Unit-3 CCSW puups were declared inoperable and the Unit 2 (2A) Circulating Water pump was secured to reduce dra sdown.

The Unit 2 CCSW pues were tested operable at 1325 hours0.0153 days <br />0.368 hours <br />0.00219 weeks <br />5.041625e-4 months <br /> and Unit 3 CCSW pumps at 1800 hours0.0208 days <br />0.5 hours <br />0.00298 weeks <br />6.849e-4 months <br /> af ter the initial discovery (i.e., >4 hours and > S hours later, respectively. Note No indications of whether tne Technical Speelfication was entered or exited, nor Indication of how long the CCSW system was inoperable for both Units).

Surry 1. 280/90 12. 09/09/90. With Unit 1 and Unit 2 at 100% power, the B Emergency Service Water Puup (ESWP) f ailed to start and was declared inoperable. Further investigation determined that peraonnel had not reset the pump trip device. Examie.ation of the other two ESWPs, A and C, found they were also in c, tripped condition, with all three pumps considered to be inoperable while the devices were tripped. The cause was attributed to procedure deficiencies. (Notel The period Cbring Which the ESWPr were inoperable Was not specified, but it was apparently beyond the Technical Specification allowable period before plant shutdown was required).

eindian Pt. 2. 247/93 009. 08/10/93. At 100 % power. Energency Diesel Generator (EDG) 22 was out of service for scheduled preventive maintenance. Service Water System (SWS) Puup 22 was inoperable becatse of f alted pump shaft. SWS Pump 21 was declared inoperable due to f ailed pump shaf t coupling. The simitaneous inoperability of SUS Puup 21 and EDG 22 required 7 hour8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> shutdown.

(WITH PLANT IN SHUTDOWW)

Oconee 1. 269/86 11. 10/01/86 All Service Water pumps were lost due to inadewate siphon flow to puups for a shott period.

Salem 2. 311/89 01. 01/01/89. All Service Water puips were inoperable for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> (corrosion / erosion).

Turkey Pt. 3. 250/89 01. 01/10/89 Service Water inoperable for 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> (Personnel error).

Rive +nd 1 458/89 20. 04/19/89 Shutdown cooling was lost for IF minutes when freeze plus falted (Pr w urat defleiencies),

eMillstone 2. 336/92 012. 07/06/92. At 0% power. With the plant in refueling mode with all fuel transtarred to the spent fuel pool, an inadvertent ESF actuation occurred resulting in e p.rtial loss of normal power. The A Emergency Diesel Generator (EDG) started and closed on bua 24C Put did not pick up any loads. After several unsuccessful attempts to energite Service Water pumps from 24C, the operator secured the EDG. About 14 inches of spent fuel pool level was drained to the Reactor Vessel.

A-12

APPENDIX A Table 3

• Potential Tetal Faltune/Dogradetion of SWs

• Category 3 (sorted by occurrence Date

• The 1991 through 1995 events are marked by e)

Palisades. 2$5/86 36. 09/30/86.

deficiencies and incorrect inpeller). Att service Unter pmps performance degraded below design (Design Calloway 1. 483/87 18. 08/15/87. On 8/15/87, with power at 100%, during a Contairs-ent Fan test, the operators discovered that the Essentist service Water (ESW) train B isolation valve to the ultimate heat sink was partially open, instead of the required full open position. Train B was declared inoperable, the valve tutty opened, and the train declared operable. The evaluation showed that this valve had been mispositioned since 5/11/64 (i.e., greater than 21/4 years). Since train A was removed from service for testing, both trains of ESW were sinJttaneously inoperable and Technical specification 3.0.3 should have been entered (Note:

Although the period was not identified, it appears that train A may havs been inoptrable beyond the Technical specification 3.0.3 time limit without plant shutdown occurring). The cause wac attributed to personnel error for the delay in discovery and inadequate (i.e., low) flow problem when baselining the EsW pwps in 1934 and in 1967.

McCulte 2. 370/87 17. 09/06/87. Both service Water trains inoperable for approximately one hour (Debels in Heat Exchanger).

Shearon Harris. 400/88 06. 02/08/88 Both amergency service water trains were inoperable when seal water supply piping configuration was determined to be vulnerable to passive failures.

Millstone 1. 245/88 07. 09/08/88. Hith power at 100%, operations discovered the B Emergency service Water (EsW) self cleaning straine* Inoperable. With A ESW train previously declared inoperette, an orderly plant shutdown was initiated as regaired by lechnical specification 3.5.B.6. The B ESW system strainer was repaired and the lechnical specification exited, with shutdown terminated. The cause was attributed to self.ctenning strainer motor f ailure (Note Fouting also appeared to be involved).

Zion 1. 295/88 19. 10/25/88. Potential for all service water pimps to lockout in a case of a " degraded grid vottsee" conditlon.

Palisades. 255/88 21. 11/04/88. Potentist loss of all service Water system paps during a transient condition due to tow protective relay setpoints.

Turkey Pt. 3. 250/89 06. 03/12/89. With Unit 3 at 100% power and Unit 4 in Mode 5 (i.e., Cold shutdown), the A Emergency Olesel Generator was out of service (Oos) for maintenance and construction activities. The 3C Intake cooling Water (ICW) pwp was taker. 00s, but Technical specification 3.0.5 was not entered due to personnel error in identifying inoperable conditions for the entire ICW system and the required plant shutdown Action (i.e., within one hour) (Note: No time period was identified with the Unit in this condition, but it appears that the limits did expire).

Browns Ferry 2. 260/8b13. 04/09/89. Att Residual Heat Removtl service Water pays declared inoperable due to flood protection manway covers not secured (Procedural deficiency).

Ir,dian Pt. 2.

247/89 11. 08/01/89. At 100% power, while operating with Emerger.cy Olesel Generator (EDG) #23 and with service water pwp #23 removed f rom service, the dif ferentist pressure for the remaining two non-essential service water pomp strainers increased above the allowable value. The entire non essential service water system was declared inoperable and the plant entered Technical specification 3.0.1, requiring a one hour notification and subsequent plant shutdown to Hot shutdown within 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />. In 1 1/2 hours, the #23 non-essentlet service water pwp was made operable by strainer cleaning. Within approximately 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />, the second

(#22)shutdown.

plant essential service water pmp was declared operable, attowing exit from TS 3.0.1 without necessitating The cause appeared to have been sitt in the strainers.

Arkansas 1. 313/89 28. 09/12/89 Both Service Water pe ps inoperable due to wiring error.

Mittatone 2. 336/89 quellfled (Design 10. 11 09/89. All su trains inoperable for 104 hours0.0012 days <br />0.0289 hours <br />1.719577e-4 weeks <br />3.9572e-5 months <br />, due to SW strainers not seismicalty

/ seismic).

Mi t t stone 1. 245/90 16, 10/04/90. Manual trip from 45% power ckJe to degraded service Water system (SWS) and Circulating Water system (CWS) conditions outing storm. Seaweed buildup exceeded screenwssh capability.

Decreased self cleaning SWs pressure on all trains due to pap drawdown (Swveral C"$ pwos still operating) and fouling of strainers.

A 13

I i

APPEm lX A f able 3 - Peteritial Total f ailure/Dogradetion of SWE

• Category 3 (Cantirased)

Crystat River 3. 302/90 18. 11/28/90. With unf t 3 at 97% power, a leak was discovered in the Nuclear services Raw Water (RW) pum consnan discharge header. $1nce in leak was increasing, att RW pums were secured. The leaking tosperature indicator (source of the leak) was removed and a blank flange installed. The Unit remained at power throughout (Note: Although the technical specification 3.0.3 is identified in the LER, it appears to be added as an atterthourht and not identif f ej during the event.

and corrective action, which would allow exit from the Technical Specification,No time period however, is identifled it is possible tht between discovery such a plantcorrective shutdown).actions could have been within the Technical Specificati m 3.0.3 time limits, .#ithout requiring Arka.asas 2. 368/91 12. 04/16/91. Both SW loops inoperable for 3 minutes (Proceducat deficioney).

Maddam he.k 1. 213/91 17. 08/23/91. With Unit 1 at 99% power, both service water headers were declared inoperable af ter all four service water pug discharge strainers indicated dif ferential pressures in excess of attowable limits, necessitating entty into Technical Specification 3.0.3. One service water header was returned to operable status in tecs than one hour, allowing exit from the Technical Specification 3.0.3. The remaining service water header was returned to service approximately 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> later (less than the fechnical Specification 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> limit). The high dif ferential pressure (D/P) indicated was due to 0/P gages becoming clogged by sitt.

McGuire 1. 369/91 14, 10/04/91. Both service Water trains were inoperable for 17 days, due to leproperly throttled valve (Personnel error).

eNillstone 1. 245/92 014. 03/12/92. At 39% power. Computer flow modeling of service Wate system (SWS) revealed the potentist for inadequate heat removal from various safety related heat enchang . hilure of isolation capability to Turbine Builditm Closed Coolinn Water Heat Exchangers could cause inadequate cooling of other loads such as the Diesel Generator (DG) auxiliary heat exchangers. Some loss of normal AC power scenarios could also result in tradequate DG auxiliary heat exchanger capability.

eMeddam Neck. 213/92 015. 06/23/92. At 99% power. The D Service Water pop had been taken out*of service for maintenance and the A kap had to be taken out for strairer cleaning. Both service water headers were then declared inoperable until one header was returned to service about 11 minutes later.

• Robinson 2.

261/92 015. 07/31/72. At 100% power. It was determined by analysis that service Water Systees

($VS) external piping corrosion, in ceabination with valves removed in support of outage activities, had rendered the SWs seismically inoperable while plant conditfor.s required it to be operable. The externally corroded piping was replaced aH ae SVS was returned to operable status. (Corrosion / Pipe) emittstone 1 245/92 026, 10/02/92. At 100% power. Piping stress analyses concluded that, as a result of external corrosion and subsequW piping watt loss, operability of the service Water System could not be assured following a seismic event. M rrosion / Pipe) eWolf Creek 1. 482/93 014 05/01/90. At 0% pnwer. A serv'ce Water system (SWS) assessment team while reviewing data to identify potential programmatic or design W 2vements also reviewed past deficiency reports, etc. that pertained to the emergency SWS and related systee.a. Records showed that for Refueling Outage IV, normal mode and Post Loss of Coolant Accident tiow balances on the A and S Essential Service Water System (ESWS) trains identified problems that likely existed prior to RF IV, since they were indicative of overalt system fouling and sWsequent long term degradation. A conservative determination was made that ESWS flows were likely below design requirements prior to Mefuel IV. [ Late filed (ER out of date ordertl

• Catawba 1.

413/93 002. 02/25/93 At 100% power. The B train Nuclear service Water system pwp discheese valves f ailed to open during pu@ start. Technical Specification 3.0.3 was entered due to A train having the potentist for a similar problem. The cause attributable to inadequate procedures for torque switch setup eCooper. 298/93 001 02/25/93. At 85% power. During design basis review, the ability to achieve the mininun require 1 SW and reactor equipnent cooling (REC) flows to essential equipment requiring cooling during a design basis event was identified. Construction error resulted in Division I service Water being supplied to the Division 11 REC heat exchanger and vice versa.

eHaddam Neck. 213/93 015. 08/16/93. At 100% pcwer. An engineering evaluation was received that determined that the previously discovered erosion and corrosion in the service Water Primary Adams Fitters housing had

. degraded the filter to an inoperable condition during a postulated design basis seismic event. Actions were started to rectore both Fitter housings to original thickness by weld resurfacing.

A 14

l APPE W IK A Table 3

• Potential Total Falture/Dogradstion of SWS - Category 3 (Contirssed) eMillstone 1. 245/93 023. 10/15/93. At 100% power. A water leak was identified from a small defect in the service Water discharge piping from the A Reactor Building Closed Cooling Water (RBCCW) heat exchanger. Based on thickness measurements and radiography, the discharge piping from the A7 and B RBCCW heat exchangers was asstaned to f all under design loading conditions.

swaterford 3. 382/93 006. 10/19/93 At 100% power. Both Ultimate Heat $1nk (UH$) Wet Cooling Tower water e

basins were less than 97% full. The systems affected b/ uhs were declared inoperable and 18 actions entered.

The cause of the event was fatture to follow procedures, in that an isolation valve was allowed to remain open instead of being tocked closet.

=Haddam Neck. 213/93 017. 11/01/93. At 100 % power. The D Service Water ($W) pts , had been taken out of-service (DOS) for replacement, and the A and B $W ptsm strainers entered the required cleaning regime. The ptsps were taken 00$ one at a time for cleaning but this resultad in both $W headers being declared inoperable.

This 00$ condition was repeated about once per shif t for the next two days because of leaves and debris in the Connecticut River, s eversont Yankee. 271/94 002. 02/09/94 At 100% power. A setf assessment identifled several design conditions which may have precluded the Alternate Cooling System from performing its intended design basis functions.

The roct cause was determined to be en inadequate analysis of the system to ensare that it could achieve its design basis fmettons under all postulated design basis events.

eMaine Yankee, 309/94 003. 02/22/94 At 100% power. Analysis of flow data revealed that the Service Water system is susceptible to flow isbalances due to heat exchanger inlet strainer differertlet pressures and design differences. The intet strainer dif f erential pressures lead to flow imbalances which require a penalty in the system's safety analysis. As a result, on February 22,1994, Maine Yankee concluded that, in the past, service water flow may not have met design basis requirements with warm river water tesmeratures. In the stauner, the river water tesmeratures rise above that required to suf ficiently cool the Component Cooling Water heat exchangers under all design conditions.

e$usquehanna 1. 337/04 008. 03/31/94 At 100% power. It was determined + hat breaker lif ting devicu snounted on all station Class It 125 VDC, 250 VDC, and 480 VAC load centers caused the toad centers to be outside of their dynamic (selsmic and hydrodynamic) qualification design basis. As a result, a decision was made to remove the stlding assemblies and trolley portions of the devices white an operability analysis was in its final stages. On March 31, the operability assessment was finallred and it determined that the load centers were outside of their dynamic qualification design basis but that the load centers were operable in their current configurations (with the devices removed). '

=0yster Creek. 219/94 010. 07/05/94. At 100% power. Both Containment Spray and Emergency Service Water

- Systems were declared inoperable due to high differential pressure on %e tube side of the heat exchangers.

A 30 hour3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> plant shutdown was ennsnenced per plant technical specifications. The heat exchangers were cleared and returned to service prior to coupletion of the shutdown. The plant was returned to full power. The cause of this event was the release of Blue Musset shells and other minimal biological debris into :hw heat exchangers.

30yster Creek. 219/94 015. 08/08/94 At 100% power. Both Contal inent $ pray and Emergency Service Water systems were declared inoperable che to lower than expected flow rates for Emergency $Uvice Water P; sups. This was caused by a release of biological material within the system, plugging the flaw sensing element. A 30 hv plant shutdown was consnended per Technical Specifications. System 2 was then started, run, and declared operable af ter continued operation raised the indicated flow to within the operability limit. The reactor was returned to fut t power prior to completion of the shutdown. The cause of this event was the release of Blue MJsset shells and other biological debris into the system.

eCrystal River 3. 302/94 013. 09/13/94. At 100% power. Lisensee personnel were mable to conclusively assure continuous operation within the design basis as a result of previous occurrences of Raw Water heat exchanger partigt plugging and fouling. Fouling was due to enarine organism growth.

overmont Yankee. 271/94 013. 10/13/94 At 100% power. Operators observed a leak from the bottom of Reactor Building Closed Cooting Water Heat Exchanger B. The service Water inlet valve was closed; however, outlet Valve V70 92C could not be closed due to en obstruction on the seat area. Both Service Water Subsystems were declared inoperable due to the unisolable Leak and a 7 day LCO was entered. After further analysis. the Alternate Cooling Subsystem was etso declared -inoperable and a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> LCO was entered. A shutdown was initiated.

Installation of blind flanges in place of the f ailed valve isolated the teak and the Service Water Subsystems and the Mternate Cooling Subsystem were declared operable.

A 15

APPEmlX A Table 3 Potential Total f ailure/Deg..dation of SWS Category 3 (Continued) eCooper. 298/94 028. 11/01/94 at 0% power. It was recognized that during low river level conditions, the intake structure weir wall configuration would create a relatively narrow channel between the Missouri River afd the intake Structure bays, and this channel had previously contained significait riprep and sitt. Ass ming design basis conditions, the existing analysis was inadecpate to conclusively demonstrate that suf ficient service water could be supplied to achieve and maintain safe shutdown. The root cause of this con 'tlon is a andification made at the erd of plant construction that created an Intske Structure weir wall, bd did not adequately assess the impact on design bases asstaptions concerning river level, ePato verde 2. 529/95 003, 06/13/95. At 100$ power. Train A Essentist Cooling Water (ECV) and supported systems /conponents were inoperable for preventive maintenance and Train A Hydrogen Reconbiner (NZA) was inoperable for calibration and functional testing, when the Train B Emergency Diesel Generator (EDC) was declared inoperable following spurious actuations of support systems. Train B ECW and supported systems /conponents and Train B H2R were now also considered inoperable (cascading TS) and Technical Specification 3.0.3 was entered. The cause of the spurious actuations cf EDG B support syst6ms was attributed to a broken EDG speed probe anphenol cable connector.

esurry 1. 280/95 006. 08/22/95. At 87% power. On August 22, Emergency Service Water Ptmp (ESWP) 1*SW P 1C was tested. The ptarp shaf t speed was found below the acceptable rangs and the piJip flow rate was found below the Alert Range. As a precaution, ESWP 1 SW P.1A was tested on August 23, and the ptmp flow rate was found to be below the Alert range. Marine growth was removed from the suction bell aid inpeller surf aces of each ptan, and the flow instrumentation was cleaned. The ptmps were tested satisf actorily .id returned to an operable status. An engineering evaluation concluded that marine growth could have degraded the capability of each ptmp or contributeJ to flow instrmentation inaccuracies as a result of annuber flow element fouling. An engineering analysis concluded that ESWP flow rates, although degrader' would have been suf ficient to meet the design bests canal inventory requirements.

eHaddam Neck. 213/95 019. 10/11/95. At 100% power. Both Service Water headers were declared inoperable due to fouling of two service Water ptmp discharge strainers, one in each header. Service Water Ptsp Strainer A had entered the required cleaning range at 0030 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> but the inability to close the manual discharge isolation valve, due to valve operator f ailure prevented cleaning the strainer. At 0227 hours0.00263 days <br />0.0631 hours <br />3.753307e-4 weeks <br />8.63735e-5 months <br /> Service Water Ptsnp Strainer D entered its required cleaning range causing entry into Techniccl Specification 3.0.3 while it was being cleaned. The cause of the event was seasonally high river debris levels due to eel grass and leavee and failure of the manual discharge isolation valve to etwse.

A-16

APPEWIN A Table 4

• Actual Partial Falture of SWs - Category 4

($orted try occurrence Date The 1992 through 1995 events are marked by e) susquehanna 1. 387/86 21. 05/2=/o6 With Power it 100% for Unit i and 91% for Unit 2, shutdown of both Units was begun when ati four Emergency service Water (ESW) system peps were declared inoperable fotlowing f ailure of the C tsW pap by cavitation damage and discovery of cavitation damage on the A EsW pop. Subsequent inspection of the 8 and D EsW peps af ter shutdom showed less severe damage and the peps were declared operable 4 days after the event, The cause was operation of po ps at flow significantiv tess than design.

Surry 2. 281/86 06. 6/16/86. With Unit 2 at 100% power and Unit i in Refueling shuth . a service Water leak was discovered in the Unit 2 Conteirnent. A Unit SNtdown to Hot stan&y was cogtr.s in approximately 32 hours3.703704e-4 days <br />0.00889 hours <br />5.291005e-5 weeks <br />1.2176e-5 months <br />. The leak was attributed to salvanic corrosion of the expansion joints.

Surry 1. 280/86 31. 10/30/86. With power at 100% for Unit 1 arw* Unit 2 it. Refueling outase, with iteactor defueled, the service water flow was lost to the Unit 1 Charging Pmp service water s@ system due to the pumps becoming airbound when a service water stralmr was placed in service without being vented. Technical specification (TS) 3.94 was entered. Approximately 19 minutes later, the af fected pumps were vented and the is exited without power roection or shutdown. The cause was attributed to proce&ral deficiencies, surry 1. 280/86 32, 11/04/a6. With power at 100% for Umt 1 and Unit 2 in a Refueling shutdown, the seruce water (SW) flow was lost to the Unit 1 Charging Ptsup SW tubsystem and to the Control / Relay Room chiller conder.er SW s@ system, requiring entry into Technical specification 3.0.1. Flow was lost when air was introduced into the system by inadequate venting of a valved in alternate SW stypty line. Venting was acconptished and flow resumed within 12 minutes, allowing exit from Technical specification 3.0.1. The cause was attributed to procedurst deficiencies.

Davis sesse 1. 346/87 11. 09/06/87. Following a reactor trip due to a 13.8kV power failure, one service water punp did in resulting not autostart.

loss De failure of one service was water due to a misstag wire (htman error) in the pa p control circuit, train.-

tales 2. 311/88 02. 01/13/88. With power at 100%, an operator observed excessive leakage from the #22 service Water ($W) pump. The pop was declared inoperable. With the Unit previously in Technical specification 3.7.4, due to the inoperability of three other $W pumps (#21, #25, and #26), Technical speelfication 3.0.3 was entered.

The #22 SW pi.sp was replaced and the #26 SW pmp preventive mainterance (silt inspection) was completed, with both papa subeequently returned to service (Note: No exit from Technical specification 3.0.3, nor duration in the Technical Cpecification, nor plant shutdown was identified. However, it is possible that the return to operability occurred with lechnical specification 3.0.3 time limits without requiring a plant shutdown).

Turkey Pt. 3.

250/88 07. 04/27/88. With the plant at 100% power, the 3A intake cooling water (ICW) pmp wcs stopped and declared out of service (00$) due to discharge piping f ailure. The 3A 3CW pop receives its emergency power f rom the A Emergency Diesel Generator (EDG) aad the 3B and 3C 3CW pumps receive their amergency power from the B EDG, which was 00$ prior to this for scheduled maintenance. The plant entered Technical specification 3.0/1 due to all ICW pmps declared (technically) inoperable, aldough the 38 and 3C pumps continued to operate on plant non easentist power. The p;ent exited Technical specification 3.3.1 approximately 1 1/2 hours later when the 8 EDG was returned to service, without the necessity for plant shutdown.. The cause was attributed to corrosion of tN, pump discharge pressure gage piping.

Indian Pt. 2. 247/88 15. 10/20/88 Wit h power at 100%, the d2 service water pop was dectated inoperable when its strainer was inoperable and required removal for repairs. Prior to this the #23 Emergency Diesel Generator and the #26 service water pop on the designated non-essential header had been declared inoperable and was stilt out for sche &ted maintenance. The multi train inoperability required entry into Technical speelfication (Ts) 3.0.1. Repeirs of the #22 service water strainer allowed exit of TS 3.0.1 in less than 4 ho' 3, with no plant shutdown. The cause of strainer failure appears to be related to fouting by sitt, surry 1.

280/89 30, 07/18/89. With unit 1 at 100% power and Unit 2 in Cold shutdown, the Unit 1 Charging

,smp service Water (SW) pops became airbound due to inadequate venting of SW Lines and were declared inoperable per Technical specification 3.3.A.7. Tha lines were vented and peps returned to service with no plant shutdown (yggi No specific time period for 'noperability was identified, although apparently a short time period.).

The cause was attributed both to design deficiencies and procedural deficiencies.

Millstone 3. 423/91 19 07/25/91 A plant shutdown was initiated from 100% power af ter the B service water train was inoperable for greater than Technical specification 3.7.4 allowabte time. The cause was attributed to mussel debris and mussel growth (no chlorination provided for system).

A 17

APPEWlX A Table 4 - Actual Partlet f ailure of gWS Category 4 (Cor.tirand) earmswick 2.

324/92 008. 10/19/92. At 0% power. A through watt teak developed on the water supply line for the mit 2 (mergency Diesel Generator Jacket water cooling. It was determined that the teak was isolated

• d was of thecaused pipe. by degradation of the cement lining of the carbon steel piping and stbsequent salt water corrosion eGrand Gulf 1.

weekly eight hour 416/93 003. 03/24/93.

recirculatius run. At 100% power. Standby Service water ptmp C motor f at ted during the room cooters and Division ill starrby diesel generator.SSW L provides cooling water for the high pressure core spray phase to pround short in the motor, The motor fatture was suspected of being due to a esembrook 1.

443/93 006. 04/01/93. At 100% power. Train A Cooling Tower ptmp discharge valve could not be fully closed due to corrosion product buildup between the valve stem ard packing follower. The pmps would not start automaticatty following a WOP with the valve not fully closed and therefore the ptmps were declared inoperable.)

eMaddam Neck. 213/93 004 05/12/93. At 99% fower. White test u the A $W pump, the B and C SW pimps were placed in trip pullout for about one hour. The root cause of the s .nt was procedurst inadequacy, in that test was not rest'icted to Modes 5 or 6.

eMaddam Neck, 213/94 002. 02/12/94 At 100% power. A pin hole leak developed on the service Water system

($WS) supply piping to Emergency Diesel Generator A.

isolation valve. The weld was mdergoing light surface The leak occurred on the first weld upstream of a manual inspection. grirding in preperstion for Ultrasonic fest (UT)

This work was part of this piping and associated welds. of an ongoing inspection and evaluation effort related to some noted corrosion Follcwing teak initiation, both SWS headers were conservatively declared inoperable since previous asstaptions regarding weld thickness and structural capability were considered suspect.

Plant operators entered Tech.1(cat specification 3.0.3 and intnediately connenced a shutdown. The root cause of this event was Microbiologically influenced Corrosion (MIC).

eft. Cathom 1. 285/9M 003. 03/04/94. At 100% power. On March 1, toon starting Raw Water (RW) Ptstp AC 10B for routine ptmp rotattun, an operator noted that ptmp motor anos appeared to stay high for a longer period of time than normat. The ptmp was insnedtately secured and declared inoperable. On March 4, a similar incident occurred involving RW Ptmp AC 10C. The primary cause of these events was excessive sand acetmulation aromd the att tion area of the ptmps.

eGrand Gulf 1. 416/94 003. 03/10/94. At 100% power. Unacceptable vibration readings were obtained while conducting a routine run of Stan&y Service Water Pimp B. Inspection of the punp revealed deterioration of the coupling bolts and washers which caused the inpetter ta rub into the wear rings resulting in premature and excessive wear. Repairs were conpleted and the ptrp declared operable. Testing indicated Ptap A met all ,

vibration and performance criteria. However, since Ptsps A and B are of the same type, Ptsp A was also j inspected. This hspection revealed simitar deterfoestion but not to the extent found in Pung B. The damage was repaired and the puup declared operable.

l

• Beaver Valley 1.

334/94 004 05/06/94. At 100% power. Due to leaking river water, River Water (RW) Header l A had been dectored inoperable on May 4 and Technical Specification (TS) 3.7.4.1 entered. The Shutdown was initiated on May 6 when it was determined that the header would not be returned to operable status within the time frame allowed by TS.

On May 8, the (e.>k was located on Emergency Diesel Generator A's RW supply line.

Non-destructive examinations were performed et various points on the associated piping. Followho repairs and l

engineering analysis, it was determined that the remaining RW piping structural integrity would be sointeirw' until the next Refueling Outage and the plant was returned to service on May 20.

eindian Pt. 2. 247/95 011. 00*14/95. At 0% power. While performing a Recirculation Swltch fest, two hervice Water (SV) ptmp start signals occurred unexpectedly. Start signals for the Component Cooting Water putps ard one Recirculation ptmo ard SV ptmp did not occur when called for by the test. An investigation of equiprnent involved in the test determined that the unexpected test results were caused by a defective relay and breaker cell switch. Upon replacement of the relay and repair of the switch, the appropriate portions of the test were successfully repeated.

i A-18 l

APPEWIK A Table 4 Actual Partial Falture of SWS Category 4 (Contiramf)

• Millstone 2. 336/95 039. 10/10/95. At 100% power. It was determined that the surveittance procedure used to verify that each Service Water Ptsrp develops at least 93% of the discharge pressure for the applicable flow rate was incorrect. The procedure included a degraded pep curve annotated to irdicate that it was adjusted to 93% of the design curve. In fact, the curve was nonecriservative, representing approximately 90% of the design curve. The sene curve, entitled " Service Water Pwp Technica'. Specification Required Performance Curve,"

was at.o included in the FSAR. A review of the most recen? surveillance reSutts conflamed that the affected pmps met the Technical Specification (TS) requ'rements. Nrther revie9 of previous surveltlance results identified instances where the pmp met FSAR curve requirements, but did not meet the TS requirements. The cause of this event was inadequate preparation and review of surveillance procedures to ensure TS requirements are met. The error was traced to the original issue of the procedure, and was carried forward through subsequent revisf ons.

• Pilgrim 1. 293/95 010. 11/03/95. At 100% nower. It was concluded that the plant was not operated in accordance with Technical $pecification (T$) 3/4.5.8 on certain dates in 1991 and 1992 because that Inservice last Program flow test data for two of the five $ alt Service Water ($$W) System pmps was less than necessary to meet the speelfication of 55 feet tetal dynamic head (TDH) at 2700 ppm. In Neventer 1994, it was discovered that 87.5 feet TDH, as measured at the pep inpeller, at 2700 gpn, was necessary to meet the specification of 55 feet TDN, as measured at the purfp discharge, at 2700 ppm. The cause of not conotying with TS daing those periods was the failure to correctly translate the basis of the specification of 55 feet TDM to the acceptance criteria in the associated test procedure. The root cause was that no direct documentation existed for the 55 feet TDM et 2700 ppm requirement tritil a November 1994 calculation identified that 87.5 feet TDH at the pmp inpeller was necessary to meet the TS of 55 feet TDH (et the pwp discharge). During the periods of plant operation outsitie of TS, reactv startups, operation at various reactor power levels, and shutdowns occurred when two $$W pmps each haf recorded flow test data less than 87.5 feet TDH. During that period, hewever, the two $$W peps in each loop had combined performance that exceeded the mininun pWp head necessary for the $$W System to fulfill its safety function.

erewaunee. 305/95 008, 12/06/95. At 98% power. Or, December 6, the A2 service Water ($W) punp f at ted to start. Inspections at the 4160 volt switchgear revealed that the pmp supply breaker closing spring was discharged. Reviews of the operating logs irdicated that the pmp had been test operated on Decenter 1. The closing spring should have charged at that time. Trerefore, the A2 $W pmp was inoperable for approximately 4.5 days. Maintenance personnel replaced the f ailed breaker and returned the pmp to service. This event was caused by a f at ture of the breaker's hydraulle rharging system. The hydraulic system'* dmp valve f alted to realign to direct hydraulic fluid to the charJing cylinder.

A-19

APPtW IM A Tal.te $ - Potential Partiet tellure/pegradetlan of gWE Category 5 (Sorted by Occurrence Date + The 1992 through 1995 events are merked by e) furkey Pt. 4 251/90 01. 02/28/90 With power at 1003, the 4C intake Cooling Water (ICW) systes was declered inoperable when the pg discharge line pressure indicator isolation vatwo was ident! fled as the wrong tyre ,

and required replacement. Earlier, the Emergency Diesel Generator (EDG) was taken out.of service, requiring entry into Technical Specification 3.0.5, as both ICW systees were then inoperable. One hour, twenty minutes later, the valve was replaced and the Unit emited 1.$. 3.0.5 without plant shutdown. The cause was attributed to personnel error in the installation of the wrong type vctve.

nMillstone 1. 245/92 024 09/16/92. At 100% powwr. The A tmergency service Water (ESW) $ traitor was found to have an extremely low itbe oil levet in t% strainer gear box ump. The f 9tture of the A ESW strainer would have resulted in a loss or degradation of the A ESW system.

ePeach bottom 2. 277/92 026. 10/13/92. At 0% power. The A Emergency service Water intet slutte Gate was fcmd not pate, electrically blocked. An A@endia R fire could cause a hot short in the control logic thus closing the elouth Texas 2. 499/93 010. 05/26/93. The coupling f rom the delve motor for the Essentist Cooling Vater train 2A Traventr9 screen was fomd damoped with coupling cracks during a post maintenance run. Trains 2e & 2C exhibited slaltar co@lIng damage in half of the coup lIngs. The co@l lng f ailures rendered all $tancby Oletet Generators technically inoperable. Unit 1 couplings were inspected and fomd satisf actory.

ekillstone 3. 423/93 012 08/05/93. At 0% power. Pieces of plywood were fomd in the A train of the service Water System which had the potential to makw the A train inoperable.

eRobinson 2. 261/93 009. 08/05/93. At 100% power. A 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> LCO was entered following service Water system (SWS) surveillance testing due to the inability of the A SW pg to meet flow requirement criteria. Technical specificatice require that with one pump out of serv'ce (DOS), the remaining ptmps be in continuous operation.

In order to concbet additional maintenance on the A Sw ptsp, the 8 ptmp was required to be secured f rom the SW header. Following testing, the A ptmp oderwent replacement. Following replacement, the 8 was again secured.

the Ltt wat %Amiltted because two SW pumps 00s is a condition prohibited by the technical specifications, eturry 1. 280/94 003. 02/04/94 At 0% power. A small hole was discovered in sn elbow in the service Water

($W) outlet piping of Recirculation Spray Systa.s heat exchanger B. This piping is in containment and provides a membrane berrier between the outside and conteirunent atmospheres. A second barrier axists et the closed SW intet and outlet motor operated isolation valves located outside containment. An evaluation determined that teskage would have exceeded 10 CFR 50 Appendia J limits, steaver Valley 2. 412/h 003. 03/14/94 At 100% power. While returning Train A Service Water (SW) Ptap to service, Technical Specification 3.0.3 was inadvertently entered. The cause of this event was an i groper testingreturned being sequence that resulted in securing the only operable SW Puup pelor to conotetthe testing on the pap to service. Sufficient service water flow was maintained on both trains of the $W system.

• Wolf Creek 1. 482/94 005. 06/08/94 At 100% power. The B Contalrveent spray P6mp (CS#) was declared inoperable on Jme 8, a*. 0944 hours0.0109 days <br />0.262 hours <br />0.00156 weeks <br />3.59192e-4 months <br />, to f acilitate testing of the p ap. fte ptmp was returned to operablu status on Jme 8, at 1447 hours0.0167 days <br />0.402 hours <br />0.00239 weeks <br />5.505835e-4 months <br />. At 1430 hours0.0166 days <br />0.397 hours <br />0.00236 weeks <br />5.44115e-4 months <br /> on June 8, it was determined that the A Essentist Service Water tttW) 1 rain was inoperable due to the inoperability of the ESW Ptap Discharge Strainer. Inoperability of the A [$W f rain results in the inoperability of the A CSP. Therefore both C$Ps were inoperable at the same time, ePrairie Island 1. 282/94 011. 11/t8/94. At 100% power. Engineering design baals reconstitution of forts have uncovered two scenselos in which a single tellure could threaten operability of the ho.121 Cooling Water Ptmp.

The cause of the event was inadequate review of electrical s@ ply and control circuitry to assure full quellfication of the ko.121 Cooling Water Ptap as a safeguard ptmp.

ePratrie Island 1. 282/95 001 01/25/95. At 100% power. An outplant operator inspecting the local control cabinet f or the Wo.121 Safeguards Traveling Screen fomd the high and low pressure sensing lines for its dif ferentlet pressure switch disconnected. This would prevent the screen f rom starting in f ast speed with continuous backwash. Investigation showed that the dif ferentlet pressure switd had probably been troperable since July 29, 1994, when cort ective maintenance was done on the switch.

3 eindian Pt. 3. 286/95-024. 10/21/95. -At 0% power.- The body of Essential service Water (81) contaltsvent t

Isolation valve SWN 43 5 was confirmed to have a smatt hole downstream of the valve disk. Ultrasonic testing showed valve body watt thinning. The plant cooled down end replaced a total of nine valves due to leakage or macceptable wall thinntreg. The cause of the leakepe was moer deposit, oxygen concentration cell corrosion and/or microbiologicatt) induced corrosion A-20

t APPEsplX A table $ Potentlet Per*.let felture/peeredation of sus Category $ (*.antiread) oteever Valley 1. 334/95 010. 12/18/95. At 100% power. - the frein B River Water header was doctored inoperable ef ter en engineertre evaluation Indicated the need to replace a rtesber empansion joint in the header.

• Wolf Creek 1. 482/95 007. 12/29/95. At 100% power. Essentlet service Water <!sW) Supply ten 8 f ailed to start when personnel pieced the Normal, Iso /Run (ISO /RUW) switch in the ISO /RUW position. Investlestien into the f ailure determined that excessive length of control virtre caused a voltage drop which prevented the fan f rom startire. The f ailure of the f an to start rendered Train B of ESW snoperable. frein B la the only train which con be isolated f rom the Control Room (CR) during a CR evacuation.

?

A 21

l l

APP [ImlX A Table 6 W5 Causes Fallure/ Degradation of Another Systese - Categpory 6 (3orted by Occurrence Date

• The 1992 through 1995 events are marked by e)

Zion 1. 295/86 01. 01/12/86. On Jan.12,1986, with Unit 1 at 99% power and Un?t 2 in Cold shutoown, a service Water ($W) valve, which swplied SW to the 18 Auxiliary f eedwater (AFW) purp oil cooler, was found closed. The valve was closed on Dec. 21, 1985 to isolate flow to a valve needing repair. Therefore, cooling was not available for a period of 22 days, which violates Technicel specification 3.7.2 requirement for shutdown within 7 days. The cause was attributed to procedural deficiencies.

Turkey Pt. 3. 250/86 18. 04/16/86. While at 100% power, a Unit shutdown was comenced due to exceeding administrative guldraines for Intake Cooling Water (ICW) system operation. These guidelines established limits to assure that the ability to provide required ICW flow through the Conponent Cooling Water (CCW) heat cxchangers was not degraded. On 4/'6/86, the 3B CCW heat exchanger was taken out of service for cleaning.

tutsequently plant intet tenperatures increased, such that all three CCW heat exchangers were necessary for operation, and shutdown coronencad. When the 3B heat exchanger was placed back in service, shutdown was rtopped and plant esitsd the administrative guidelines. The cause of the event was both elevated heat sink tenperature and fouling of the heat exchangers.

forley 1. 348/86 14. 0o/01/86. With power at 99%, and the 1A Charging Punp out for maintenance, the 18 and iC Charging Pup were ceclared inoperable due to high 9 ear oil temperatures, and Technical Specification 3.0.3 was entered. The 1B cooler was cleaned and Techn! cal $peelfication 3.0.3 was exited within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> without a plant shutdown required. The cause was attributed to sitt and sediment in the pump ott coolers.

surry 1. 280/86 24. 08/13/86. With Unit 1 and Unit 2 at 100% power, loss of one Control Room and Relay Room Air Conditioning Chiller resulted in the mits operating with only one operable chiller. This is v ohibited by the Technical specification and preparation for shutdown was initiated in accordance with Technical specification 3.0.1.

Withia the Action statement time limit an a&fl.lonal c5tller was returned to service for both units, and preparations for shutdown were terminated (Technical Specification 3.0.1 was exited). The cause of f ailure was due to caogging (sitting) of the chiller by unfiltered river water flowing though the tubes (i.e., the strainer was oypassed). The chil'ers were unclogged and the strainer returned to service, farley 2. 364/86 11, 10/15/86. With Unit 2 at 94% power, Technical specification 3.0.*, was entered tecause both trains of the Control Room bergency Cleanup (CREC) system were inoperable due to the re.pective service water (SW) systems swplying CRECs had been removed from service. The 18 SW system was renoved f rom service for modification and the 1A train was secured as it was thought to be the source of leakage in the Copponent Cooling Water Heat Exchanger room. When the source of water leakage was determined to be Unit 1 (i.e., not Unit 2), A train SW system, the Unit 2 A train was returned to service 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and 10 minutes later, with Technical Specification 3.0.3 was exited without plant shutdown.

McGuire 1. 369/87 06 03/10/87 With power at 100%, the Control Room ven*llation and Chilled Water (VC/YC) system train B was declared inoperable due to low condenser water flow : service water stgplied) signal. Train A had been declared inoperable previously, due to maintenance. Technical specification 3.0.3 was entered with both trains inoperable. Seventeen minutes later, train B was declared operable when the service water s@ ply valve was reopened, the Technical Specificatinn 3.0.3 was exited without plant shutdown. The cause was attributed to personnel error in closing the service water supply valve.

McGuire 1. 369/87 31. 11/25/87. Wich power at 95%, a performance test of Conponent Cooling (KC) Heat Exchanger (HX) 1B determined that the W Serential cressure (D/P) across the heat exchanger exceeded the atiowable accep*ance criteria. Unit i ent 6d Technical Specification 3.0.3 because KC HX 1A had been declared

'noperable ear.ler when the outlet ten 5% sture control valve f ailed open. The valve was achinistratively blocked open and the Technical Specification 3.0.3 was exited withiri one hour. The KC HX 1B was cleaned, successfully passed the D/P test, and returned to operability. The cause was due to fouling in the heat exchat.ger.

Davis Besse. 344/88 07. 03/04/88. With power at 61%, both air operated service water tenperature control valves (interf acing with conponent cooling water system heat exchangers) were declared inopera' 4e due to the potential for moving from the fail safe position following a loss of instrument air. this resulted in entry in Technical Specification 3.0.3. The Technical specification was exited within 12 minutes, without plant shutdown, and was declared operable. The root cause appears to be design deficiencies.

Catawba 1. 413/88 15. 03/09/88. With Unit 1 at 97% power, Unit 2 (at 20% power) tripped during a feedwater transient with all three auxiliary feedwater (CA) ptmps automatically started as designed. However, the motor driven CA ptmp 2A swapped suction Jutamatically to service water when a sustained low levet suction pressure cond! tion was sensed, and raw water f rom the take entered two steam generators. Inspection of the flow control valves f(r CA pupps 2A and 2f identified that the valves were clogged with shredded Asit tic clam shells.

Following the discovery, both Units were taken to Mode 4, H3t Shutdown.

A-22

APPE21X A Table 6 SWS Causes f ailure/ Degradation of Another System Category 6 (Contirued) solem 2. 311/88 15. 07/26/88. With power at 99%, the #21 Conponent Cooling Water (CCW) heat exchanger was made inoperable cbe te significant service water ($W) leakage downstream piping, which also made the #22 Copponent Cooling Water Pwp (CCP) inoperable. Since the #21 CCP was out of service &e to design modifications, both CCPs were inoperable and Technical specification. 3.03 was entered. The #21 CCP was returned to service prior to shutdown conpletion. The cause of SW piping f ailure was due to corrosion.

Wolf Creek 1. 482/88 16. 08/25/88. With power at 100%, Technical $pecifications were violagtwice due to error of interpretation. On 9/22/87, with the B train Air Conditioning Unit (ACU) previUusly declared inoperable, the A train Essential service Water (ESW) system was declared inoperable. Technical Specification 3.0.3 should have been entered, but was not. Also the Action statement for Technical Specification 3.7.6 was not entered into when repairs took longer than at towed (Note: The duration apparently exceeded 7 days with both systems inoperable, with power at 100% and no plant shutdown). The care was attributed to personnel error.

Robinson 2. 261/88 19. 09/05/88. With power level at 0% (Cold shutdown), inspection of the Contairvnent f an Coolers revealed biological fouling. The extent of fouling reduced the overall cooling coil irrier diameter by 20%, thmby reducing the cooter's design heat renovel capacity. $1milar blefouling was observed on f an motor coolers ouring an earlier (8/31/88) inspection. Because of the tack of a performance monitoring system, the loss of operability was not detected with the plant at power operation, nor was the duration identified for th*

degraded condition. The cooters were cleaned and returned to service.

McGuire 1. 369/88 24 09/12/88. With power level at 100%, performance monitoring of flow and dif ferential pressure (D/P) for Conponent Cooling (KC) Heat Exchangers (HX) discovered that the 0/P for one of the Unit 1 yd both of the Unit 2 KC NXS were greater than the opwebility limit of 8.6 paid. The subsequent performance test on the 1B KC HX f ailed and Technical specification 3.0.3 was entered because train A of the ECCs was out for maintenance, ard thus, both trains were inoperable. Subsequently a high velocity flush was successfully conpleted, HX was retested, the system was declared operabls, and th Technical Specification was exited for Unit 1. The cause was attributed to seasonal envirornental f actors (bioligical fouling and debris).

Trojan. 344/88 29. 09/16/88. One train of safety injection was lost due t ' clam debris in the tube oil cooler (supptled by service water system).

Mc(,uire 2. 370/88 11. 09/17/88. With power level at 100%, the component ;ooling (KC) Heat Exchanger (HR) 2A was taken out of service for cleaning. While retesting 2A, the pressure dif ferentist across HX 2B exceeded 8.8 psid operability limit and Action Statement of Technical specification 3.C 3 was entered because both treins of EC were inoperable. Less than one hour later, following a successful flush and retest of HX 2A, the sysnti was declared operable and exited Technical Specification 3.0.3 without need for plars shutdown. The cause waw We to debris and fouling in heat exchangers.

Oconee 3. 287/89 01. 01/12/89 With Power at 100%, testing of the A eM C Reactor Building Coollreg Units (RBCus) was performed due tn previous f ouling concerns. The test data analysis indicated *! at service induced fouling reduced the performance of the RBCus to tmacceptable limits and the plant was shutdown to the Hot shutdown cordition per Technical specification 3.3.5.

solem 1. 272/89 05, 01/27/89 With power at 100%, Technical spee!fication 3.0.5 was entered te to both trains of emergency core cooling system being inoperable One train was inoperable due to an inoperable service water (SW) header, white the other train was inoperable due to the inoperability of the diesel generator. The Conponent tooling Water heat exchanger was re, ' I, returning the SW header to operability. T.S. 3.0.5 was exited without the necessity for plant shutdown. The cause was determined to be erosion /corrotion of the SW intet piping to the CCW heat exchangers.

Perry 1. 440/89 27 09/25/89. With power at 100%, a loss of control power to the Emergency service Water (ESV) system punp discharge valve, due to an incorrect jmper placement, resulted in the ESW and its dependent Division ! Emergency Core Cooling System (ECCS) and Dieset Generator (DG) to become inoperable. Since the Division 111 ECCS thigh Pressure Core Spray) and DG were previously out of-service for maintenance, the p. ant entered Technical Specification 3.0.3.

1. f ter the Division !! maintenance was cleared and it was returned to operabitity approximately 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> later, Technical Specification 3.0.3 was exited without plant shutdown. The cause was attributed to personnel error.

N aenn Harris 1. 400/90-03. 02/20/90. With plant at 100% power, the 1A SA train of Essent;al Services Chm wi Water (ESCW) systeni was declared inoperable f or planned maintenants of the associated 1A SA Emergency Service Water (ESW) ptrp. The 18 58 train had been previously declared inoperable due to air birding in its P 4 ptsp, and therefore, Technical specification 3.0.3 vos entered. The A train clearances were removed and the technical specification 3.0.3 was exited approximately 13 hours1.50463e-4 days <br />0.00361 hours <br />2.149471e-5 weeks <br />4.9465e-6 months <br /> later with plant shutdown. The 8 train was returned to operability within the initial Technical specification allcwable limit by venting the service water p*P-A-23

~, u . =

. I APPENDlX A Table 6 . sIwi t.auses f al'are/ Degradation of Another System Category 6 (Contirund) l Clinton 1. 461/90 11. 05/14/90. Division 1 and 2 Emergency Oleset Generators (EDGs) were inoperable due to incorrect stiprynent of shutdown service water supplies to the EDG coolers, resulting in inadequate supply of cooling water.

Susquehanna 2. ;&8/90 06. 05/29/90. With Unit 2 in Cold shutdown and Unit 1 at 100% power, it was discovered that the Unit 2 C Residual Heat Removal (RNR) pump motor olt cooler had developM i tube leak, causing oll/ water mix into the motor internals. The cause was initially identified as a common move f ailure attr.ibuted to microbiologically 'nduced corrosion (MIC). A decision was made to shut down Unit i and not restart Unit 2 until all RHR motor oil coolers had been replaced. Further analysti determined the f ailure to be mder deposit corrc; ion, accelerated by the presence of manganese.

Mills?on. 3. 423/90 20. 06/14/90. With Unit 3 at 80% power, the B train ResicLal Heat Removal (RHR) Area Cooler Unit 1B was fomd to be degraded, due to fouling. $sseguent engineering analysis determir.ad that both trains of High Pressure Safety injection (HP$l) and Quench $ pray (0$$) were rendered inoperable when the A HPSI and 0$$ pwps were removed from service, with the B area cooler fouled. Therefore, both trains of OS$ were inoperable fer 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> and both trains of HPSI were inoperable for 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> (Note: The Unit did not enter Te-hnical specifica' ion 3.0.3 cr equivalent with either of these dual train inoperability conditions, nor was the plant shutdown).

Millstone 3, 423/90 23. 06/1$/90. On 7/5/90, with power at 80%, a detailed eNineering evaluation determined that both trsins of Containment Recirculation Spray had been inoperable simultaneously for a prolonged period, due to fouling of the heat exchangers. Previously, on 6/18/90, the B train containment Recirculation Pmp Area tuoter was found to be degraded when damage and fouling was found in the heads of the heat exchangers. Earlier, an 6/15/90, the A train coolers were fomd to have fouling and were repaired (Note: The Unit did not enter into an operabilt t/ Technical Spect fication, even when train A was discovered to be degraded. The time period where both trains were Inoperable is also not identified, but appears potsible that it exceeded Technical specification 3.0.3 or equivalent time limits before requiring a plant shutdown). The cause was attributed to t lofouling of the cooters and inadw vte surveltlance procedures.

F t . Ca t hom 1. 285/90 25. 09/29/90. It was determined that conpoet cooling water (CCW) system would fail on toss of control air. Also, the raw water system (i.e., service water) discharge pressure was inadequate to backup the CCW systn for supplying cooling water to the containment coolers.

Surry 1. 280/90 14. 10/23/90. With Unit 1 at Refueling shutdown and Unit 2 at 100% power, the Unit 1 and 2 Recirculation $pra/ Heat Exchangers (R$NXs) were declared inoperable. A special test of Service Water (SW) flow to Unit 1 B and C RSHXs had indicated that adequate flow may not be obtainable during a Design Basis Event, which could result in delay or prevent depressuritation of the Contatrvnent to a subatmospheric pressure condition, in accordance with Technical Specification 3.0.1, Unit 2 ses placed in Cold shutdown. The recbced SW flow was caused by macrofouling (Blofouting) of the RXHXs from marine growth and fragments of pipe coating Haddam Neck 1 213/90 23, 10/27/90. With power level at 100%, two of four Containment Air Recirculation (CAR) f ans were dectored inoperable af ter falling a service water surveittance flow rate test and entered Technical specification for system inoperability. Unit was placed in Cold shutdown 25 hours2.893519e-4 days <br />0.00694 hours <br />4.133598e-5 weeks <br />9.5125e-6 months <br /> later. The root cause was excessive debris which clogged the Service Water System Filters.

salem 2. 311/90 42. 12/20/90. With power at 100%, a service Water (SW) system through wall leak at the inlet pipe to the #21 Conponent Cooling Pwp Room Cooler resulted in the inoperability of the #21 SW header, two groups of Contairvnent Fan Cool Units (#21 and #22 CFCus), ard the #21 Containment spray Room Cooter. Technical specification 3.0.3 was entered and the Unit was shutdown. The cause was attributed to pipe corrosion.

Haddam Neck 1. 213/90 32. 12/27/90. With power at 100%, all four Containment Air Recirculation fans were declared inoperable due to fouling of both service water filters that swply the fan coolers. Technical specification 3.0.3 was entered and power reduction conenenced. One of the filters was clead and the T.S. 3.0.3 arproximately one hour later, without further power. The root cause was attributed to excessive sitt suspension in the rher water.

Farley 2. 364/91 03. 04/16/91. With Unit 2 at 100% power, Technical specification 3.0.3 was entered because both trains of the shared Control Room Emergency Alt Cleanup system were inoperable, @e to both Service Water (SW; system trains being inoperable. The A train SW system was determined to be inograble because a supply valve had been closed erroneously. The valve was reopened and the Technical Specification 3.0.3 was exited in less than one host no plant shutdown required.

Vermont Yankee. 271/91 12. 04/23/91. Reduced emergency diesel generator (EDG) and air comprecsor cooler service water ($V) flow was caused by incorrect SW discharge valve aligrvnent.

A-24

APPE SIR A Table 6 gWE Causes f ailure/ Degradation of Another System a Category 6 (Centstaasd) eMatch 1. 321/92 003. 01/21/92. At 100% power. Air operated cooling water supply valves to Emergency Equipment Room coolers A and B failed to automatically open during the routine performance of the Core Spray p ap operability test. With both the normel and stan&y coolers for this room inoperable Core $ pray pwp 1A and Residual Heat Removat pwp 2A and 2C were declared inoperable. The cause of the ever.t may have been solenoid operated Valve failure oeuad Cities 2. 265/92 007 03/04/92. At 0% power. It was determined that both the A erj the B Residual Heat Removal (RHR) room cooters were plugged in enfess of their design margin. With both loops of RhR ef fected, the ability to provide long term cooling following an accident was questioned.

esurry 2. 281/92 003. 03/25/92. At 100% power. The C main CR/$witchgear room chiller was declared inoperable because of high SW dif f erential pressure caused by sedimentation. B chiller was considered inoperable because its power source Emergency Diesel Generator 3 was out of service for planned refueling outage maintenance.

eMeddam Neck. 213/92 012. 04/25/92. At 99% power. Both service water filters which supply SW to the contattament air recirculation f ans were declared inoperable due to high dif ferential pressure. Problem repeated saae day and on 4/26/92. Caused by excessive debris and sitt suspension in the Connecticut river due to heavy rains, emcGuire 1. 369/92 006. 04/30/92. At 984 power. Air was discovsrod in the Nuclear Service Water assured makeup piping associated Witu auxiliary feodwater ptsup suction header s@ ply isolations, the CA system was detersiined to be past inoperable. On May 2,1992, the Unit i and 2 TD pugs were isolated from the potential source of air from the RN discharge header and were declared inoperable, eWNP 2. 397/92 017. 05/08/92. At 0% power. Thermal performance tests of the Residual Heat Removat A Heat tachanger determined it was unable to perform its design basis safety fmetton. Monitoring of the $$W was not adequate in predicting fouling magnitude and rates, osurry 1. 280/92 009. 07/12/92. At 100% power. Three main control room / Emergency switchgear room chltters became inoperable due to inadequate SW flow to the chiller condensers caused by fouling of the Y type SW strainers located at the inlet to ecch chiller. Fouting of the Y strainers was caused by deterioration of upstream rotating service water stralners and by sudden releases of debris within the (Jrvice water system.

eZion 2. 304/92 004 07/15/92. At 95% power. Emergency Diesel Generator (EDG) 2A declared inoperable due to high Itbe oil temperature and the 2A $1 pump was declared inoperable che to low recirculation flow. The 2A EDG is the emergency AC power source for the 28 Safety injection ($1) pump, therefore both $1 peps inoperable.

Zebra aussel shells plugged the EDG 2A lube oil cooling system. The 2A $1 p6sup inoperability was categorized

• as a conponent failure due to orifice restriction.

ecued Cities 1 254/92 027. 10/09/92. At 0% power. Inspection of the High Pressure Injection System Room Caoler determined that the room ct,oter was fouled beyond design margin with sitt and small debris. The cooter was primarily s@ptied from the non safety related Service Water System.

eMonticelto. 2A3/92 016. 11/07/92. At 95% power. The check valves in cross ties between normal and emergency service water failed tc seat property. Failure to seat could have effected flow to Division !! control room sentilation system and Division !! emergency core cooling system pwps, eTE! 1. 289/9F002. 01/29/93. At 100% power. Bypass of both decay heat service coolers due to personnel error. During performance of a weekly procedure, an auxiliary op**ator fellod to fotlow established operator work practices and established a valve lineup which caused river water to bypass both Decay Heat Service Coolers simultaneously. When discovered, the proper alignment was trunediately restored.

etalvert Cliffs 1. 317/93 005. 06/30/93. At 100% powar. Both independent Contalrunent Spray systems were inoperable for 45 minutes. No 12 Cs system was inoperable for scheduled maintenance. No. 11 CS system was inoperable because the outlet valve for commtwnt cooling water bupptv to its shutdown cooling heat exchanger was inoperable because of disconnected valve ap uator linkage. The actuator linkage separated due to pivot locking plate f ailure. The repts;ement plate subsequently cracked and similar cracked plates were found on two other mit 2 valves.

eWNP 2. 397/93-031. 11/09/93. At 100% power. Main Control Roum HvAC system will not maintain controt room tenperature below design basis limit of 104 degrees F following a DBA. Caused by inadequate design margin in the original design including a f ailure to account for cooling coil fouling.)

A 25

• l APPEle!X A Table 6 SWS Causes falture/ Degradation of Another System Category 6 (contfrued) eBeaver Valley 1. 334/94 001. 01/09/94 At 100% power. During testing of the Train A River Water (RW) Ptsrp, total RW flow rate through the system was 6100 ppm. 1echnical Specifications require a mintRJm floW rate of 8000 grsn per train. It was determined that the low flow condition was due to fouling of the heat exchangers l and a plant shutdown was initiated. f ollowing heat exchanger cleaning, the total flow through the Train A l Recirculation spray Heat Exchanger was 9700 ppm. The majority of debris found consisted of apprcximately 30%

stam shells and 70% f errous corrosion products and turbucles.

eQuad Cities 2. 265/94 003. 01/30/94 At 97% power. The Unit 2 High Pressure Coolant injection Room Cooler was declared inoperable between 1200 hours0.0139 days <br />0.333 hours <br />0.00198 weeks <br />4.566e-4 months <br /> and 2100 hours0.0243 days <br />0.583 hours <br />0.00347 weeks <br />7.9905e-4 months <br />, because of low cooling water flow. Flow was increased to an acceptable value and the surv*ltlance f reewcy accelerated to every two weeks. The cause of the event was slit buildup in the cooling water system.

e inwrick 1. 352/94 003. 02/06/94 At 0% power. During a Unit I refueling outage, the Unit 2 Chief Operator (CO) erroneously interrupted Residual Heat Removal Service Water (RNR$W) flow to the 18 Residual Heat Renovat Heat Exchanger (RHR HX) instead of securing flow to the 2A RHR HX resulting is a loss of Unit i residual heat l removal 36 minutes af ter the error, the Unit 1 CD sonitoring Unit 1 reactor coolant tesperature informed Shif t l Supervision that the temperature was continuing to increase. The B RHR$W ptsrp and the 1B RHR HX were then returned to service. The primary cause of the event was personnel error due to a f ailure to perform self check.

eMittstone 1. 245/94 013. 03/28/94. At 0% power. Analyses indicated that Essential Service Water (ESW) flow may be te$s than values asstaned in the post Loss Of Coolant Accident (LOCA) Containment Cooling analysis.

Following a postulated LOCA, Low Pressure Cootsat injection (LPCI) system flow may neqd to be throttled to satisfy net positive suction head concerns. A corresponding reduction in ESW flow is then required to molntain a 15 psid dif ferential pressure. This reduction in ESW flow. Mich occurs only when the LPCI flow is throttled, may result in less than the credited heat removal capabil , from the LPCI heat exchangers and a subsequent heatup of tentairvnent chove the maxinsn calculated teaperau ..

ePer y 1. 440/94 015. 06/09/94. At 0% power. On June 2, riergency scrvice Water (ESW) system keepfllt supply was transferred frca the alternate supply to the normal supply, the Service Water (SV) system, af ter completion of a design change to the SW system. On June 9, it was discovered that ESW loops A, B and C keepfill pressures were below speef fications. An engineering review of system line+up and parameters determined that CSV A, B and C lnops were operable during the June 2 to June 9 time period. The engineering review also identitled that during priods of low Lake Erie water temperature, operability of the ESW system could be affected. The cause of the reduced keepfill system pressures was identified as a deficiency in a SW system design change, eWolf Creek 1. 482/94 006. 06/15/94 At 100% power. After replacement of actuators on certain Essential Service Water (ESW) valves, during the retest activities, the ESW flow balance was altered to a con *:guration that may have not provided sufficient cooling water to the related Emergency Diesel Generator (EDG) for safeguards operation. Technical specification 3.8.1.1, Action b requires, in part, that offsite power sources be demonstrated operable within one hour af ter declaring an EDG inoperable. That Action was not entered at the appropriste time for either train. Consequently, the appropriate surveillance procedure was not conpleted in the required time. The root cause of this event was inadequate job scoping in that interaction with other systema was not adequately conside ed in the MOV test sequence, ePeach Bottun 2. 277/94 008. 08/" % At 100% power. It was discovered that the Emergency Core Cooling systems (ECCS) and the Emergency Diee snerators (EDG) may have bee i Technical Specification inoperable. This occurred when an Emergency servite ! (ESW) Outlet valve was closed and lef t mattended for approximately 47 minutes during Valve Operation Tt A1 Evaluation System (VOTES) testing. Having the valve in the incorrect position jeopardized the operability of the ECCS and EDGs due to reduced cooling water flow rate. Cause of this event was that less than adequate controts were established to ensure that MO 0498 was continuously manned charing votes testing, i souad Cities 1. 254/94 010. 08/08/94. At 0% power. When attenpting to start the Train B Control Room (CR) air conditioning (HVAC), the compressor repeatedly tripped on high pressure. Operations declared the Train B of CR HVAC inoperable. Operations dimvered that the on line Service Water strainer ups) eam of both CR HVAC conpressors was clogged with su:f. 1, t problem was not diagnos d earlier due to a f alse indication of adequate flow, eMaine Yankee. 309/94 018. 12/04 '94 At 100% pcwer. While flushing the Cunponent Cooling Water (CCW) Heat Exchangers, a non-Licensed operato

• misaligned valves rendering the SCCW system inoperable. The operator later realized his error and aligned th e valves to their proper positions.

e A 26

l i

APPUCIX A Table 6 SWS Canes f ailure/Degradatiwi of Another Systese - Category 6 (Contiroed) of urkey Pt. 3.

250/95 003. 03/09/95. At 60% power. The intake Cooling Water (ICW) flow rate through the Copponent tooling Water (CCW) heat exchangers fell below that assuned in the design basis. The reduced flow rue was dJe to en influx of aquatic grass and algae onto the basket strainers of the ICW flow path upstream of the CCW heat exchangers. The strainers were cleaned ard flow returned to required levels. The plant was operating at 60% reactor power as a conservative measure due to the potential for an increasths influn of aquatic grass and algae into the ICW and circulating water systems.

ePato Verde 1. 528/95 005. 04/07/95. At 0% power. Engineering personnel determined that tubesheet blockage (primarily corrosion nodules) fourd in Emergency Diesel Generator (EDG) B's Jacket water cooler would have reduced the mininun required best rejection through the cooter. This condition could have potentially af fected IDt. S's perf ormance under design basis accident conditions. At the time, EDG B was removed from service for surveittance testing and preventive maintenance. A preliminary evaluation attributed the cause to failure of the epony coating that lines the carbon steel spray pond supply pt9tng.

eCatawba 1. 413/95 001. 04/20/95. At 100% power. Technical specification 3.0.3 was entered due to 5 eta trains of the Control Room Ventilation (VC) aid Chilled Water (YC) systems being inoperable. Train A ;S the VC/YC System was declared inoperable on April 18 for preplanned preventive maintenance. On April 20, TC chiller 8 tripped due isolation, for about 32 seconds, of its Nuclear service Water (RN) discharge flow. The RN system discharge was being realigned f rom the standby kuclear Service Water Pond to the take. Inanediate corrective action was to reestablish the discharge path. This event was attributeo to system alignment, tegout and restoration not being verified by Unit 1 senior Reactor operator.

eMillstane 3. 423/95 011. 05/15/95. At 0% power. Mussel shells were found in a Recirculation spray system (R$5) beat exchanger which could have made it inoperable. The shells had been swept to the heat exchanger by service Water flow during valve testing in the refueling outage. The apparent cause of_ the fouling was a high density of ausset plantigrades (late stage larvae) in the spring of 1994, concurrent with hypochlorite system problems which allowed the plantigrades to settle at that time. This condition could have existed for the previous six to nine months with the plant operating ard at times when the other train of Service Wate; or R$$

was inoperable for survet tlance testing or other reasons.

eindian Pt. 2. 247/95 014 05/18/95. At 0% power. A Service Water leak was detected inside contal*vnent at the discharge flow element weld f or Fan Cooler Unit #22. The leak was estimated at 0.00026 gpm. The ten cooler was isolated, the leak repaired, and the fan cooler returned to service. The leak was at a weld connection between the 10" discharge carbon steel cenent tined piping and stainless stee' instrunent line transl tion weld.

The probable cause of the leak was inadequate or defective coating of the two metals at the yeld which resulted in galvanic interaction ard corrosion of the carbon steel, eLa Crosse. 409/95 002, 06/16/95. At 0% power. Technical specification (TS) 4.4.5 requires an operable fire hose stations in certain locations. When inoperable, T$s require a 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> fire watch or routing m additional hose of equivalent capacity to the unprote

• area within one hour. On June 16, it was noted by a La Crosse staf f manber that the High Pressure Servics .

• o the Containment Building, which supplied water pressure to the Contairvnent Building Basement hose stas. . M isolated.

esen Onof re 2. 361/95 014. 08/13/95. At 99% power. A 0450 hours0.00521 days <br />0.125 hours <br />7.440476e-4 weeks <br />1.71225e-4 months <br /> operators started Unit 3 sal'. Wster Cooling (SVC) pm p 3P114 Edison had recently modified the electrical system logic such that this action caused a breaker in the Unit 2 second source of offsite power to shift to MANUAL. Edison considtrs *he second scurce of offsite power inoperable when in MANUAL. No audible alarm for the change in control status was provided.

Therefore the operators were not aware that Unit 2 had entered Technical Specification 3.8.1.1 Action at aN the required surveillance was not accomplished within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. Control of the breaker was returned to AUTOMATIC at 1410 hours0.0163 days <br />0.392 hours <br />0.00233 weeks <br />5.36505e-4 months <br />.

eBeaver Valley 2. 412/95 007. 10/03/95. At 100% power. An operator observed that the valve stem position for a Recirculation Spray Heat Exchanger (R$NX) Cooling Water Discharge Valve, was different f rom equivalent valves in redmdant sWsystems. Iollow up investigation determined that the valve was not opening as far as expected, These valves are normally throttled to a position established via an Operating Surveillance Test (OST) which verifles there is adequate cooling flow through both trains of the Recirculation Spray system. On April 24,1995, this test resulted in the valve strete time being set at 18.96 seconds. An OST performed on May 4,1995, recorded the stroke time of this valve as 8.43 seconds. This was considered acceptable as it was within the established A$ME and Technical Specification limits and the operators performing the test were not aware of the April 24 as left values. The calculated flow through the B train of the RSHX with the valve set for en 8.43 second stroke is less than the Technical $pecificatice required value, but within the Design Basis.

A 27

APPE W IX A Table 6

• gME Causes f ailure/Degradstion of Ano%er System Catopory 6 (Contitaasd) e$urry 1. 240/95 010. 10/06/95. At 100% power. On October 6, at 2250 hours0.026 days <br />0.625 hours <br />0.00372 weeks <br />8.56125e-4 months <br />, Unit 1 was at cold shutdown and Unit 2 was at 1001 power when the four Component Cooling Nest Exchangers (CCMX) were determined to be Inoperable dJe to teesheet macrofouting. Two heat exchangers were cleaned and returned to service to meet Technical Specification requirements for one Unit operation.

A root and Inoperable cbe to LW teesheet blockage caused by hydroida cause evaluation other deterzined that the CCMX were marine material. Engineering analysis determined that actual heat removal capacity of the four CCMX was adequate for the required heat toads, theref ore, there were no safety consegJences or Imlications eJe to this event.

• Crystat River 3.

302/95 022. 10/18/95. At 100% power. During the performance of Train B Decay Heat closed Cycle tooting $ystem (DC) flow beleme, two cogonents (the motor cooler for the Decay Heat Service Raw Water Ptsy and Decay Heat Removal Heat Exchanger 18) were is.nd to have measured flow less than the flow required in the Enhanced Deslen Basis Doctament. When instrument ers/ was considered, the DC cooling wster itow rate could be less than an anel',Jad flow rate of 2918 gpm. This was odermined to be a condition outside the plant design basis and the DC system was deter 1nined to be Inoperable. The primary cause of this event was an inadequate procedure, eOronee 1. 269/05 007. 12/06/95. At 0% power. During testing, the Low Pressure Service Water (LPSW) flow to the in required. Low Pressure Injectico (LP!) Cooler would not increase from approximately 2500 tpm to 5100 spm as The key which locks the 1A LPI cooler outlet block valve stem to the valve opera tor was found out of the keyway, allowing the butterfly valve to partially close. Due to the potential for reluced LPSW flow to the 1A LPI hovenber 6, cooter, 1995. the 1A LPI train was declared technically inoperable for the period of December 3,1992 to Assuning a sinitte falture of the 18 LPI Train along with the failure arde associated with the valve, heat removal f rom the LPI cooters could have been degraded following a design basis loss of coolant accident. The degraded heat removal from the LPI cooters would not have interrupted LP! flow to the core nor resulted in challenges to the containment design pressure. However, the degraded LPI cooler heat removat capacity pressure. could have resulted in exceeding the envirorvnental qualification lief ts on containment tenperature and A 28

APPENDIX A Table 7. SWS Related ASP Events for the years 1986 through 1994.

.s tPLANT NADE

• LER ~ SIG. CAT. CAUS2 EVENT DATE CDPR TYPE AT EVENT DESCRIPTION 1 OCONEE 1,2 & 3 269/86-011 2 F 861001 1.1E-5 UL Load shed test, LDSW/CCW/ECCW fail from abnormasy low take level.

2 DAVIS-BESSE 1 346/87-011 4 E 870906 5 8E-6 T Trip with unavadable essental bus, SWS, RH 3 MCGUIRE 2 370/87-017 3 D 870906 7.0E-6 T Trip due to overcurrent in IA comp motor and 1 SWS & PORVs out 4 CATAWBA 2 414/88-015 6 B 880309 2.7E-4 T Asiatic Clems from nudear sennce water degraded the APW System 5 DAVIS-BESSE 1 346/88-007 6 F 880304 1.6E-6 T Component Cooling valves drift close 6 HARRIS 1 400/86-006 3 F 880208 4.8E-4 UL SWS pump sealwater unavailable 7 PALISADES 255/88-021 3 F 881104 2.7E-5 UL Potentialloss of seNice water pumps 8 TROJAN 344/88-029 6 8 880916 8 6E-5 UX Both trains of Si and one EDG inoperabie 9 ZION 1 295/e8-019 3 F 881025 1.0E-4 UL Potential for AFW and CCW pump auto-start failure 10 ARKANSAS 1 313/89-028 3 F 891012 2.8E-4 UT Two service water pump circuits inhitzt auto-start Y 11 CLINTON 1 461/90-011 6 E 900514 4.7E-5 UL *~Avision

. I & il emergency diesels inoperable b 12 FT CALHOUN 1 285/90-025 6 F 900929 1.7E-6 UX Component cooling water would fail on loss of IA 13 SALEM 2 311/90-042 6 C 901220 1.3E-6 UL Si and one train of emergency power inocerable 14 APKANSAS 2 368/91-012 3 E 910515 4 BE-4 T Both normal service water trains fouled by debns 15 VT. YANKEE 271/91-012 6 F 910423 2.9E-4 L Extendedloss of offeite power 16 TMI-1 289/93-002 6 E 930129 3.1 E-6 UX Bath Residual Heat Removal Heat Exchangers Unavailable 17 CATAWBA 1 & 2 413/93-002 3 E 930225 1.5E-4 UL Essenbal SW potenbeHy unavailable during dual unit LOOP Abbreviesons.

CDPR = Conditional probabibty of pctential core damage associated with the event C.lG CAT. = S;, A in.e Category T = Transient caused Trip CAUSE = Cause Category L = Loos of OffWe Power UT = Degradallon or unr. " ' ~^y of equipment for plant to respond to Trip UL e Degridslion or unavailability of equipment for plant to reopend to less of OffsRe Power UX = Degradetion or unavailabisty of equipment for plant to respond to Loss Of Coolant Accdent

APPENDIX A _ _ _ . - - -I Table 8. Percent of CDF Attributable to SWS Fail re (From iPE Analyses Submitted t) NRC). ,

Table is sorted by plant type (PWR Vs. SWR), NSSS, and %CDF).

8 L C. CO DKT PLAar7semest .tA73 i N R % CUF swop- e t c. C O. Der? PLAememes R419 7 N R % ceF lowoP=

ii 19eo i 19671440 PE RRY 1 '120S!eio 3! 46 1! 64 1972! i9721309 mhE YANKEt 1825 =P 'C ti i 04 EAR ,

2! 1970 ! 1971 ] 24$ MILLSTONE 1 600 97 0 iti 17 3i 67i 1971 ! 1971 i 255 iPAttSADE & SOS 'P'Clai N RCi f 933 Sl O!3i 15 i l

~

3l 1987 } 1967 ! det ICLINTON 68! 1973} 1974 i 265! FORT CALHOUN [478 [C 4 ! SAR )

4! 1974 l 1976 i 331.DUANE ARNOLD !$30 IB !O i3 j 14 2 !NRC/R 60i 198$ i 1995 i 342 iWATE RFORD 3 i1104 P iC id i l l' 1964 ' 19 ]46352! LIME RICK 1 (105S[8lOlii 86: 60! 1972 ! 197'I ?$0 7URKE Y POINT 3 893 P'W2!

1 56SAR

$!190s 1990 353l LIME R4CK 2 !105JSjo 11 06: 61 ! 1973 i 1973 ! 2511 TURKEY POINT 4 093 iP !W'2 i 663ENR

?! 1964

~

19M1397 lWNP 2

~

2 1100f8+OJ 8 9 NRCiF' 82! 19e$ j 198S i 413 rCAT AWSA 1 i1145 !P lvv 2 ! 47 NRC/F 8 1975 ! 1976 324 BRUNSW6CK 2 it21 IDI 2 6SiSAR 63i 1984 319e6 414 ! CAT AWBA 2 i1145 iP !W 2 i .

47 INRC/F j _1976 31977 32$ '8MUNSWi[K 1 l821 l8 'O l21 6 3;&NR M; 1977 1977 348 ;F ARLE Y 1 !829 .P 'W 2 3 28 6 NRC/F 10 1973! 1974 277 ;PE ACH90 JOM2:1085 8.iG it ! 4 6!W/SSFi 65! 1981 1981 3M :F APLEY 2 829 :P lW,2 i 28 5.NRC/F 4 i it ! 1974 i 1974 4 SiW/SSFI 96!i MO 1981__. 327!$EQUOYAH 1 1948 lP ;Wl2 l 279 PE ACHOOTTOM31005 l8 !O !11 28!NRC/F i 12; 1978 ! 1979 ! 306! MATCH 2 17M !8 l0 l2 ! 4 3 NRC/F $7j i381 ! 1992 329;&EQUOYAM 2 1148 iP !W!! 28 NRC/F )

13! 1974 i 197$ i 321! HATCH 1 '777 18 jo ifi 2 7'NRC/F $6i itM I 1964 443 !CALLAW AY 1 1171 IP !W:3 24 2 t '

14! 198711968 i 410!NINE MILE PT 2 !1000 !S iO it ! 2 2 !&NR to 1970 1971 461 } Rot'NSON 2 700 P!W'2 24 t iNRC/F J Q939 1980 ! 219lOYS TE R CR E E K iM0 !B io it ! 21!&AR 70 1975 1975 31S i COOK 1 1030 'P !W'3 23 6_SA/R 16: 1974 1975 { 200l DROWNS FY 2 jicej5 B iOl2i 1 Si&NR 71 1978 1979 316 jCOOK 2 23 Si&AR 30! 1973 1974 250! BROWNS FY 1 t1005!Bjo82t 1100 lP lW:3 1 Si _72 1970 1970 2016 PolNT DEACH 1 407 'P 'W'.3 218;NRC/F 32i1970 1977 296iBROWNS FY 3 1100S !B jo l2 13l 73 1972 1972 301!POWT SEACH 2 487 !P ;Wi3 214 'NRC/F 17i1982 1984 373 LASALLE 1 !1074 i9 i0 is 0 91 741 1981 1981 300!MCOUIRE 1 1190 !P !W!? 20 $!

iti1964 1984 374!LASALLE 2 i1073 ]B fO !3 0 Si 75 19s3 19M 370!MCGulRE 2 1180 iP iW!2 20 $!

19j 19e6 1986 3541HOPECRE E K 11067lBiOHi 0 71 76 19e6 1986 ! 482 IWOLF CREE K 1 1970 iP iW:4 _12 Di 20! 1972.1972 2711VT YAN8.EE iS14 iB !O !1 ! O 3;&AR 77 1976 1976 i 334!SEAVER VALLEY.836 8P !W!1 98 EAR 21i 1974 ! 197S ! 333!FITZPATRICK i821 '8 iO !1 ! O tiW/S$FI 78.1982 i 1964 i 3e6itutWE R 900 tP (W'2 86 22! 1962 i 1983 i 165!B80 ROCK PT IT2 9 !O I31 79j 1967 j 19871400! HARRIS 900 iP iW:2 7 il 23 19eF1989 i220'N1 WE MILE PT 1 )620 :8 iO it ! 'SAR 90! 19e0 i 1980 ! 443!$EASROOK i 11200 'P !W!1 67 24! 1970 > 1970 i 237 DRESDEN 2 i794 8 'O '3 ' NRC/F ali 1980 i 1981 i 311 ' SALE M 2 11115 P iW 1 _

65-25

• 1971 < 1971 ' 249 iDRESDE N 3 794 9 iG 3 7 NRC/F 82j 1964 ! 1995 i 275 D6ASLO CANYON 1086 iP ]W 6 49' 26 ! 1970 ' 1971 ! 243.MONT4CE LLO $45 6 O !)i s NRC/F $3! 1985 ! 1986 ! 323 DIASLO CANYON 1919 P f W S 49' 27- 1972 i 1972 i 293 'PaGRIM 1 SS$ :S 10 'I 4AR M! 1986 ! 1986 i 423 MILLSTONE 3 '11M P!Wh: 48' 24 1971 i 1973 i 2*> OVAD CITlf 81 ~ i70e ;810 i3 i ' N RC/F* SS! 1967! 1988! 213!HADDEM NECK l680 _P IW 1i 3 4!SAR 29l 1972 .19731265 IOUAD CITIES 2 j790 :D iO !)! . N R C/P M! 1985 j 1986 i 464 8YRON 1 i1120 !P 'W-3 ! 3; 31! 1974 3 1974 i 2M]COOPE R S T AT80 778 i810 is I ' N RC/F 87! 1967 ! 1987 i 455l8YRON 2 0120 P i !Wl3 a 3:

_3Q962 [ 1983 ! 387 SUSQUAMANNA !10S$ ' ) ~O ;1 86j1976l 1977 ' 272 SALE I M1 '1000 !P 'W 1 ! 2 6 SAR 34 1982! 19951416 'OR ANDOULF 1 !12$0 :8 iG !!!

~ 69! 1900 } 1900 l 445!COtAANCHE PE A t1150 iP 'W 4 8 25 35! 1964 ! 1985 388 ISb&QUAHANNA i1065 !8 !O !1 r toi 1976 i 1976 286ilNDIAN POINT 3 '985 P {Wl11 2 4 NRC/F 36] 1965 i 11108 454iRfvER PEND it38 18 !O I4I 91! 1987i 1987 412iBEAVER VALLEY.433 _P 'W:1 23' 37;1995 19811 141 FE RMI 2 1003 i8 'O :3 i 92i 1984 i 1988 4 des iSOUTH TEAAS 111290 jp iW:4 2 1 ' N RC/F*

38_1974,1974 ! 269 jf MI 1

~

Sie iP 8 1 ! 15 7 EAR 93! 1980 ! 1989 i de9: SOUTH TEAAS 211250 IP iWie 2 t iNRC/P 39 1974 ! 1974 ' 313 ! ARKAN&AS 1 ie50 iP iS id I 9 $ jNRJ/R 94i 1973~ 1973 I 232 iPRAJRIE ISLAND iS30 iP IW!3 13 '&NR 44 1974} 1974 287iOCONEE 3 ie87 iP !D !! 19 NRC/F 96!1974 1974 ~30$ iPRAIRIE ISLAjN$30 lP !Wj3 1 Si&A/R 41i 1973 i 1973 2asiOCONEE 1

~

l487 iP i812 19!NRC/F ts 1974 1974 306!KEWAUNEE [636 lP !W!3 0 8!&A/R 42! 1973 1974 270iOCONEE 2 sea 7 !s' !B !? 1 DINRC/F ~~97 1987 19ee den!SRAIDWOOD 1 i1120 P lW!3 04}

43 1977 1977 302iCRYST AL RfvER I42S ip !b ;2 j&NR es ites taes 457 !aRAIDWOOD 2 #1120 PiW;3 0el edi1977 1879 346iDAVIS DESSE 1 it06 P19 13 iNRC/F to 1987 1987 424 !WiO TLE 1 0.2 i f1079 .P (W!2 eS! 1982 1983 381 &AN ONOFRE 2 11070 4P ic :S1 10! 100 taas 1989 425!VOOTLE 2 10's lP iWi2 02 46!1983 1984 382 SAN ONOR ItE 3 !1MO iP iC iSI 10 1! 1 01 1987 1988 2M ISAN ONOFRE 1 438 iP !WIS 47i 1986 itse 628 PAL 3 VERDE 1 11221 iP IC !6 99! 1C2 1989 1970 244!OINNA 470 iP iWi1 !NRC/P 46] 1986 'Be8 $29 #ALOVERDE 2 (1221 ~P !C iS 99! 103 1972 1977 200!SURRY 1 788 !P Wj2 i&NR dei 1987 19&J 530 PALOVERDE 3 1260 P iC iS 9 ti 104 1973 1973 281iSURRY 2 TOS iP Wl2  !&A/R S0! 1978 . 1980 388 ARKAN&AS2 912 PiCl4 8 iiNRC/R 106 1973 1973 297 ZION 1 1040 iP WIS i&Nif

$1! 197411975 317 CALVEstT CLIFF 645 P IC i1 2 Si&AR 10s 1973 l 1974 247 ilNDIAN POINT 2 $73 iP iWI I i 52! 1976 j 1977 318 CALVERT CLIFF iM5 P iC l1 26&NR 107 1973 1974 304! ZION 2 i&NR 1040 iP iWl3

$3] 1976 i 1975 336IMILLSTONE 2 it70 P ;jCg 24&NR 106 1975 1976 344 jTROJAN 1130 iP iW:5

$4i 1976 l 1976 335 ST LUCit 1 830 !P !C !? 15 t NRC/F*. 100 1979 1978 33ejNORTH ANNA 1 907 iP7W;2  !

65j 1963 j 1963 300 $1. LUClE 2 j830 jP jC j2 110 1980 19e0 33el NORTH ANNA 2 907 jP jWl2 14INRC/F* l l IC. Deee of treal CatsceMy

• SWOP Desi9nomens C 0 e Commeresel Openision Dees DKT e Deceiet NRC e Porturmed by NRC Rate Eleans Power Racin9 SA e ser Assenement Dr LJoentee T e Type SWR (5) er PWR (P) W = Werved N e NSSS Fe Fue R e NRC Region R e Recluced

%CDF = Pereert of everes IPE core esmeSe Doguancy ese to intemel Ennts SSFI e SWOP e SWsOP1 tr=p man Pe/tormed ei 1E31 twough ites

• e SWSOPI trW*i Peet Ptert The 1PE SWS Core Demoge Dsctions shown ere Dem emelors- For PWPs 748W. T4CW, T. UHS. For BWRs- T.FSW, T. UHS A-30

e .

APPEND 6X A TaNe 9. i._ ..uy of SWSOPt RepoFt Individual Findings and issues 1 1ARMANa AS teUCLEAR 190W94 9420 41 Velves ~'

,D _ _Smgte Fosse Petoneel Seigne Feewe Concern I

2 ARMAMeAS NUCLEAR 1908f94 942042 , inserwnenlehen __ ST _ Procupwe irryeome4_Fe4ee te Remove Tog Donces Aner Teet_ _

3 ARMAtt8AS NUCLEAR 190004 9420 03 VARIOUS __

UEhnete Heat Se*___OM_. Equip irieperatory Seewece We_se_r System Urevesebee___ . __ _

J ARMANSAS NUCLEAR 190824 9420 04 _

D _ .inadecuale Analyene Feewe to Pertonn a 10CFR 50 59 Eveaunt_ers _ _

_S ARMANSAS NUCLEAR 190ef94 9420 45 VARtOUS ._ ,0, _ .W_ ese,,r_ Hemme_r _ Cervec9ee Achens for Weser Hemmer

_6 , CALVER7 CLFFS 05/1994 944001 Heat Eschsagers, _ _ _ _ _ __

D_ _ ,Inadequale Hast_R_ SRW Heat Ehoperatumy Margr_i_

05/1994 M9042 Instrumentellen ____ _

__1C_AL_ VERT CLFFS

_ 0 44 _ ende9mee Memt ___, hemmeonencey - . - - _ _ :.

'8 CALVERT CLIFFS 05ft994 9441rA03 Host Esenengere _ ST _ inadequese Teshng_ Host Escharger Porterrrence Teesmg__ _

05/19f94 94J00 94 Veeves ___

9_. CALVERT CLIFFS 09/0W94 960 .r1 ST _ hedequese_Tesang__.m-earvece test Program _

_10 CATAW8A ._

Ullemose Heat Sint __ _ D_ _ g Ansepss ;g of Shoused SNSWP_@ fleer

_t 1 CATAWGA f190994 M1747 VARIOUS D_.tnadeguese Analyese

_ _ Fat to Peeppty Trar sesse Reg Ramos to Speesh A lhec_

12 CATAW8A 090004 M1743 Ireshe1OutfoE _ _ _O__.y_@ Short Descharge Leg Venacou o

_13_.CATAWgA GDOW94 M17-04 SW Pumps 1 Motors _ _ D _.C _ , . - - i^ - -

C--, _ Preeschen for Serwece Weber Pwvys 14 CATAW9A 0D0994 94 17-05 VARIOUS _

OR4 Procedure arrylement . Fe4 to Pareym Quaggy Reessed_Q_per Proc er Owegs.

15 CATAW9A OW0094 M17-08 16 CATAW9A ODOW9+ 94-1747 SW Pumps f $_4esers . , _

D_. ._ _

Rowegue_ Foewe to Propedy Review e Sassey Eveseemen _ , _

Ulumene Heat Sir

• __ D, , _D_re@_ Centret No tese h *ah*_ _

OWO99_4 941748

__17_.CATAWeA VARIOUS OM _ ( Roweare

_ _ __ .Tenyerary Stenen 94eeAcenonjTy M Receve _

_18_,CATAW94 090994,941749 41344408 values OM, Procedu_re Wiplement

_ _ Fee to Enowe veeve loceq Devices Are M eentresed _

f

_19 CATAWgA OW0094 9 17-10 .. Piping OM _ J - Moed Flush Program .,. _ _ J.

__ ST _ inadeq Surveeence G) _20_,CATAWDA OWOW94 9417-11 UIMmese Host Se* Fed to Adegestely Perform Survedkonce of TS Parameters ___

^

21 CATAWBA .ODOWFf M17-12 VARtOUS . .OM_igProcess_e L; _

PMTe ter Pre <feelned Werer Teohs .

_22 CATAW9A 090004 9417-13 Instrumengeseen OM _ % Inst & Corer anyteen. of Pigg to Revesar As-Found Out et tolerance Instrmes___

23 CATAW9A 0D0044 94-17-14  %.-' - --

__. OM_ _.inodeq het & Cener Querefying Fleur Mesourement Ener

_24_ CATAWeA 090004 94 17-15 VARIOUS __ OM _Conoceve Aceano _._ CorsecSwe Actone to Cenemens Adve oe to Queery , __

_25 COOPER 090994 090004 940441 949442 VAR _IOUS VARIOUS D_ inaccunsee FSAR Feeure to Revise USAR _ _ _ _ ,

_26_. COOPER D_ _ Doei@ corWel Deelen Centret 27 COOPER 080884 "' 're Host E@ ,.ST _ . _ . _ _ _, 1 Teemng _

- Teateg et Reactor Equipt Coeliry HT Eschengers_ _

_26 CRYSTAL RfVER Otr2545 95-15 01 VARIOUS D Shigte Feeure gi_. __ ter SisTo Tanit Nerogen Cy- . _ , _ _ _ _ _ ,

_29_ CRYSTAL RfvER OW2545 95-1542 VARIOUS _

D DesignfDec. Certet Praesceen Ageenet the Dynamic Eftects of LOCA OW2545 951543 30 CRYSTAL RIVER Host Eschengere D .C. c.g- RCP Seat Casser Tutie Fease .

31 CRYSTAL RIVER OW2545 95-15-04 Heat Eschengers D _ __Gw r- __.

No Roast Preesceen for Decay Heat Removet Host Eschengers etr2545 95-1545

_32 CAYSTAL RfVER Heat Escfionsors D. C ,_ _ l . . Reser Wesse Removed 9em Heat Eschengers _

33 CMYSTAL RfvER 00f2W 95-1548 insensmenennen .D_ inadeq Inst & C_ener Seepew for Service Weser Header Lew Pteesure 34 CRYSTAL RfvER 80er25ftp j 95 507 Walues S_T_ .W=== Teseng _ Femme to Inchsde Check Velse SWW-356 in sie isT Program _ _

35 CRYSTAL RsVER Oef25es 95-tses inserumoreanen OM _medequese Procedure Inconect Armuncioser Roepense Precedure _

38 CRYSTAL RfvER 00f2585 95-1543 Instrumordeeman OM y__ Procedwo inconytene Annuncieser Roepense Procedwe _ __

37 CRYSTAL RIVER Cer2545 95-t510 Trosseng Seseens OM_ inodeg _3ne_t & Cerdr_ Tressens Screen DNIsrerent Pseeewe Seepene ]

3e CRYSTAL R VER Oer25e5 95-15-ti TreseRng Sc=no OM _y Processe , y Censiderellen et OfP Instrumenessen Feeure M 1Pe Processe__

30 DAVIS SESSE 12f2W93 93016 41 Values .

D ._ Preredwo Wysoment Fenwe to Per9erm to CFR 50 59 Eve 8ueseze , _ _

40 DAVIS SESSE 12r2eS3 93016 02 Vehmo 0, __ . Single F__sewe , Potenline Norgengearece su4h Single Feewe Creene____ . _ _ _ .

! 41 DAsis sESSE v2r2ee3 9301643 UWnm Home s** D Seenec Cmgery Senswc Design er e= Ummene Hout e. _ __ _

i 42 DAVtSBESSE 12r2993 93016 44 34ee3-00s .Vaewoo ST_ inadeques e Toseng _ _ ,Feewe to anchsde Cornem Veswee in the IST W_ .

i -43 DRESDEN 080303 9300841 . Heat Eschengers__ _ _ .D_.Designose. cordret_LPCafCCSW Host E= changer C__opabney_ _,_ _ _ _, _ _ _

44 DRESDEN 0W0393 9300642 Vesses ST inadequese Teneing Fahee te Perform ousterly tST

• Type Decepneser s D - Design, ST - Survemence Tenang. OM - Operasene Mensenance

4, Ja 5 ~

APPENDIX A Table 9. Summary of SWSOPI Report Individual Findings and issues e pwst - . cAfa ^ FWIDWONO. ~LER qCOWONENT TTPE' IS30_pg F3M00100 TITLE - t 45 DRESDEN 06/0193 93 DOS 43 Misc _ Pumps . ST ,

a_tadtguaje Testeg_ JDOS 660048. -Quarhrrtyt DG C ( l'ater P=mp_T_est tST__ __

46 DUANE ARNOLD 12/15/93 9301841 P, ping _ D. .inadequ .te Analys's _ , Segmic r k_ l ESW3HRSW Pipa l n t_ _ .

47 FARITY 1091/93 93-1341 Heat Euchange_rs ST _ enerfequets Testing _ F_q H_eath Performance Tq e_ L _ , _ _

_48 FARLFY 10/01/93 93-1342 VARIOUS D inadequate _ Analyses _Wa'er Harmner Assumpton . _ _ _ , _ _ _ _ _ _ .

_49 FARLEY 10rDig3 93-1343 VARIOUS OM Sitteg _ _ _ _ _ . __ _ _ Sa Redu&m Efforts

_50 FARLEY 10r01ts' 93-1144 _ _ _ _ _

Valses ,

ST inadequate Testing Fabo incsimfe Turtune 8ktg Rc9 urn tse wivs in !ST_ Program ,

51 FARLEY 10c1/9s 93-1105 mstrumente9an OM Inadequaie FAalnt __ Instrumentation Out of Tolerance _Withosd Evaluation _ ___ _ _

_52 FAF4F ( _10/01/93 93-1106 _

Pipeng __

ST inadeq Survedance_ inadequate TS Surve llance _ Test for SW Pipe, Integrity 53 FARLEV 10/01.93 93-1347 _

SW Pumps / Motors , _ ST _ Inadequate Testmg_ _ inadeguate %mmum Flowrate Basehne_ _

_54 FARLEY 10/01 S 3 931348 __

Contarnment Coolers , 4T _ hadeq Survedlance inadequate Conrmt Cooper Flowrote SurvesRance m procebe, _ _ _ , _

S3_GINNA 01t3_0S 91-201-01 VARIOUS D DesW control _ P%h^ Test Revew___ _ _ _ _ _ _

56 GINNA 01/3i G2 91-F1-02 VARIOUS D inadeguate_Mes _ Reessessmere of SWS Hydraulle ModeljSections 3121L ,_ ___

_57 GINNA 01/30/92 W-N1 M Heat Eucha gets D. _ Safety Class Rectassification of Spent FP Nt Erch to not safety retated 58 GtNv* 01/30/92 91 U107 Valve- 0 _ Single Faaura FaGure to Con _s6 der Smgle Fadure of Pump _Descharge _ ___

59 Get M 01/3092 91-201-08 SW Pumps / Motors D, S6ngte Failure _

_ inconsjstency Between Licensing _ Basi _s an_d SW Puinp, TS

_60_GINa- 01/30 S 2_91-201-11 _ JVARIOUS , D__fnaccura'e FSA Inaccurate UFSAR informstion (See.tnon 317) _ _ _ _ _ _

91 GINNA 01130/9? 91-201-12 "r .:. hiiun OM inadequate Pros

• Jure __ Fasure to Estat4sh Low-Pressure SWS Setpoirt _

62 G!NNA __01/30 S 2 91-201-14 _

CW Pumps / Motors . , _ ST _ Inadequate T*" g _ Pr pershonal Test An6mahejs Section 3 4 IL__ _ _ _ __

63 GINNA 01/30/92 91-201-15 ___

,VARiOUS OM , inadequate " ~

Practsee of Performmg Surve" Testing Whde redundant OOS_ _ _ _ _

64 H 8 ROBINSON 07/3093 93-1241 . _ Ve. %_a_ __ D_ _ _ _ _ Procedure er E Fa!Iure to Est_st$sh Approp Design Control Ov_er SWS _ _

h IV 65 H B ROBINSON H.8 ROBINSON 07/30/93 93-1242 07/3093 931243 VA.!!OUS Heat Exchangers , _ , _

_ D_ . . _ inadequate L usr. g_NR_C Review and Fonowwp of _th_e Licensee s_ Corr ____ __ _ _._,

66 D_ _

DestgrvDoc; control __. Femse to Fonow the Des Change Process When usmg.Bettone_ . , _

67 H.8 ROBINSON 07/30/93 93-1244 VARIOU_S OM _ inadequate Procedure Failure to prov6de_adeq_ instructione in AOP422 _.

68 H 8 ROBINSON 07/30i93 911205 _

.. Heat Exchenge_rs_ _ _

OM, ,

inadequa'e Procedure NRC FoNow-up of SWS HI Ewchanger_inspec' p me *. tests _ _ _. , _ _ _ _

69 H 8 RO8tNSON 07/30/93. 9_ 3 42-06_ __ _ _ , _ _ _

SW Pumps / Motors _ _ ST Inadeguate Testing _ . Fee to Estattsh Approp Veration Acceptance Crye _ _ . _

70 H 8. ROBINSON 07/30/93 93-1247 instrumentation _ ,

OM . _

inadequate Mawt__ Fe4 to I r*" Procedure _1br_ instrument CQatr e ctwcks _ , _ _ _ _

HATCH ,03/22/94 9441 01 VARiot/S D, inadeqtMa Anaysis_ PSV 71 ,, _

w Modet Venreca.non _ __

, 72 HATCH ,0Y22/94 9441-02 VARtOUS _ _ _ D __ inadequate Arnlysts HEt' -. tWS_a_Wwhen_a Cor(ament._______

73 HATCH 03/22 S 4 9401-03 _

instrurrertation D, inaccurate FSAR__ Nece r - <n 4 SW Radiation Monstar OM _

74 HATCH 03/22/94 9441-04 VAktOUS Inadegust_e Procedure , Fellure dure or inadequate Procedure 75 HATCH 0 _3/2274 944145 Irtoise/Outrail OM Debris in intake inadeqt ~ ' dverse to gehty Actions _ _ _

76 HATCH 03/22/94 9441-06 .VARIOUS _ .OM __ BM _ _ __ CtamAA ainshateves _ __

77 HATCH 01/22 S_ _49401-07 Piping ST___ Corr _oeion RT Progry sovelopret _ _ _ _

78 HATCH 03/22/94 944.11-08 Evv Pumpe / Motors _ OM _ Oorrestcet _ Pump Colo  %

yi y Evaluations 79 HATCH Oy22/94 9441-09 SW Pumps / Motors ST_ .inadeq C:svedlance _ FaRure to tesue_.g_ , . ociated with_the RHR SW System __ _ _

80 tNDIAN POINT 3 OW10S4 9341 01 Valves O_M _ Irdequate Mamt. ,We Maintenwo of Velve SWS-99

, 81_ INDIAN POtNT 3 02 W 94 93-81-02 Vafves _

OM , , _ Esguip enoperatdlity__ Contsenment teotauu.1 C a[stwlty , _ , _ _ _ ._

82 INDIAN POINT 3 02/10 S4 9141-03 Pipeg OM Corrosion Corrosion of SWS_Ptptng __

l V INhAN POtNT 3 '02/10 S4 9141-04 286S3 450 VARICUS D Design / Doc control _ Fa5 to EstatAsh & Nintam DestControlon air supply syst_ _ ._ _ , _ , _,

84 Kiv/AUNEE 04/01/94 9400341 Containment Coolers D, _ ina4quate Anaysts_ _ . The tryn was concemed that tht clesign change package for DCR N ,,

I KEWAUNEE ( 4/01S4 9400102 Heat 1 Exchange _rs ST in Jequate Ana'ysrs Heat Exchanger Performance T_esteg_

_85_ __, ,_ ,

86 KEWAUNEC 04/01/9 3 3003G VARIOUS _

OM , _ Procadure implement _ _ Program Process Controts _ _ _ __ _

_87_ KEWAUNEE 04/01/9e (+400104 . i@wab ,_ .OM _ Egulp incperatWilty_ _ .,Non-functioning Flow instrumentatio_n _ , _ _ _ . __

88 KEWAUNEE 0401/34 M0345 Inswnentation D inaveg Inst & Contr u.ack of Flow Messunng Instrumentation

• Type Derignations: D- Desigr 5 - Surveitance Testeg. OM - Operations "_..._ -

u-O e APPENDIX A Table 9. Summary of SWSOPl Report Ind8vidual Findings and issues

- e Mast . enge waso. - t.as com J;..i Tver - tesue poemso mts -

89 MON TICELLO 09r30/91'9201401 ESF/AFW Ptmp CQ D_ , _ ,tnadequate Anaisns_ The team t$enerned a ~eakness m tr e heat _ load ariages for RHR/CS, 90 MONT! CELLO 09r30/92 9201402 Heat Exchange _rs D_ _ ,tnedeguue Anaysrs The te en noted on wror for mewnum tryeshold over,a_t heat ufer coe*ficien_t

_91 MONTICELLO 09/30/92 9201403 Roun Coolers ___ ST Ira.Q Testing _ System Flow Ba'anctng_

92 MO ITICELLO 09'30/92 9201SO4 VARIOUS ___ . ST __ .inadeguate Testeg_tST Program 93 MONTICELLO 09/30/92 9201405 263/92-10 812 VARIOUS ST _ inadeguate Testeg Notice of Vloistion

~ ' ~ ~ ' ' ~ ~ ~ ~

~~~

~04 NINE MILE 09/10/93 9180LO1 VARIOUS OM Roo: Luse Evat QA and Corrective Actms

~ ~ ' ~ ~ ~

95 NINE lEILE 09f10/93 '914402 ,

VE iOUS ,

OM[ Equip Degradation

, Lon2Term Corrective Actes for E5 System ~~

~-

96 OCONEE 02/11/94 493-2541 VARIOU3 ST _

~

_ , . _ inadeq Survemance_ .Faflure to Adequatg PerEx~m SVIfE Actions 97 OCONEE 02/1144 f3-2502 _

Valves _ _ D_ . ,_ Se' stir c Category _ _ Turtwne Buermg isotationMdadure vulneratetni '~ ~~ ~ ~ ~~

98 OCONEE .02/11/94 93-2503 VAPIOUS 99 OCONEE 02/11/94 912504

, _ _ O_ .Inadeque's Anatsrs Fad to Per8erm A Celeskh hcdDesign ((~

D

, Piping _ inadegun Anaysts_, inedeguate Eval of CondR_lo_ n Adverme to QuaiPy tsy Engineenng Ital __ OCONEE 02/11S 4 932_505 IVARIOUS _ D. E_ quip inoperabdity AddMnal Validation of RBCU Everus+ ion inputs 101 OCONEE 02/11/94 912506 VARIOUS _ ,, OM _ inadequate Proce( *e_, Actions to improve Opera *or R_esponses to Abnormel evenE 02f11rG4 93-2507 102 OCONEd SW Pbmps / Motors _

_ O_ _ Safety Class ined Classdica' son of Siphon Support Eqms for LPSW Supply __

103 OCONEE 02/11/94 93-25-06 VARIOUS ST _ inyguale Teshng_ inadeguate SSF and ECCW Testmg__ _

104 OCONEE 02f1144 93-2509 . Misc. Pumps _ _ __,_ O_ Ecgupp inoperabdidy_ CCW Pump NPSM anf_o_rm, atian 105 OCONEE 02/11 S 4 9125-10 VARIOUS ST inadequate l esting _ inadequate HPSW SBO Test ___

106 OCONEE 02/11/94 912511 VARIOUS_ _ _ D. [loodmg__ ___

J_ocassee Dom Fallure IPEJnaccuracies 107 OCONEE 02/11 S 4 93-25-12 VARIOUS D, __ inadequate Documents _ SWS Proc /Dwg _Centent er Procedure Irnplement Inadequacies 108 OCONEE 01/11/94 9125-13 Valves ST Inadequate Testng g

W 109 OCONEE 021IS4 9125-14 M!sc. Pumps __ D_. Inadequate Anaysis ..

Orn6ssions of LPSW ChecSt Valves from IST P,rogram _

Review of Revised ASW Purnp NPSH Calculation

]10 OCONEE 02l11/94 93-25-1S .VARIOUS D, _ inadequate Analysis Admirdstrative Controls for Lake Keowee 111 PALISADES 0604S4 4400241 . Heat Exchan[,qs_ , _ __ D_ , _ Ogssurization ___

Lack of_ overpressure Protection for CCW Heat Emetwngers_ ___

112 PALISADES 06/04 S4 94002 02 _ _ _ _ _

VARIOUS __

D inadequate Heat Rem OMey Mergin of SWS 113_. PALISADES 03/04/94 94002 43 SW Pumps / nnetors _ ST. _.tr eeguate_Teste- , ' Uncertamty in IST ump Acceptaye Crdens_ _ _

114 PALISADES 03/04 S4 94002 44 .

SW Pumpe / Motors _ D_ . _ S6ngle Failure Sing!e Facure Vulne:abatees 115 PAllSALES 03/04S4 94002 4 5 Vat.es .

O We Testeg Leak Testerq Important SW vatves 116 PALISADES 03/04S4 9400 1 06 instrumentation _ OM _ Equip _Degredation Ben _t instr nt Tubing _ _ _ _ _

g 117 PALISADES 0344S4 943024 7 Hest Enc

• an9ers S T _ __ Flow imbatence__ System T (D_eficiencies 10/0893 9301241(DRSl_

118 POINT BEACH Ultimate Heat Sink D inadequate Anagsts Service Wu Lesen Temperature _ _ _ _ _ ,

119 POINT BEACH ICOL93 9301242(DRS) Room Coolers ST _Irgante Testing Batter Room %ota /erformance Testing IN POINT BEACH _OM_

10/06S3 9301243A(DRSl Vahres .

inadequate Procedure Failure to hclude Acceptance Crferia h Malntenance Prcc 121 /OINT BEACH ,p/0893 93012438(DRS1 .

SW PumpstMotor. OM __ inadequate Procedure Fatit:e to include Centingency Actens M Procedu o 122_ QUAD CITIES s /01/92 92-201410 Room Coolers inadequate Analysis __ Heat Lead Calcuts*#ons for RHRSW and DGCW Pmp Vedts__

123 QUAD CITIES 05/01/92 02-201420 ..SW Pumps / Motors D _ O_FlowImbalance

_ Operabety of Unit DGCW Sptem (Section 4 4 and 7.1)

O_ _

124 QUAD ClTIES 05/01192 92-201-030 Valves Singie Fa%re Str gle Falture_Vulnerabattesjsection 4 5) _ _ _ _ _

125 QUAD CITIES 05/01/92 92-20104Q Votves D Equip _Quali_ficaten RHR Heat E rhanDer Valves Not E.O .ggrty Cualified 126_ QUAD CITIES 05/01/32 92-201-050 Valves 7_. inadequate _ Testing incomplete inservice Teding Program

_. de_

127 ZlAD CITIES 0501/92 92 201-060 265/92407 Room Coolere Inadequate Heat Rem Unit 2 R'IR Heat Exchanger Room Cooier i eperable __

128 SEQUOYAH 04f21/95 95-0341 VARIOUS OM GL 6413 Non compf GL 89-13 Action Not fully implemented 12J_ SEQUOYAH 04/21/95 954342 ,

VARIOUS D Cesign/ Doc. Control hadequate Desi- Oontrei 130 SEQUOYAH 04/21/95 95-0103 Misc. Pumps D Design / Doc Controt_ interpretanon of Designfests Flood _ ____ _ _

_1_31 nEQUOYAH 04/21/95 954104 VARICLM _ _ . OM_ inadequate Procedures _ inadequate Procedures er improper Pro (edures_ ___ _ _ ,

132 ISEQUOYAH 04/21/9' 950105 VARIOUS OM Corrective Actions No titte ln database

" Type Designations D - Design ST - Survemars;e Teciary. OM - Operations Mahtenance

]

I APPENDIX' A Table 9. Summary of SWSOPl Report Individual Findings and Issues j .. . - ,

.m. _

gg~ .<M N TYP9* 168U9 mTmA 133 SEQUOYAH 04/21/95 954346 wARtOUS OM inadequate Proc _edure_s Procedures Referenchg NonemeNng Procedures 134 SEQUOYAH 04/21195 9543-f2 _ _ _ _ _ , _ , . . Room _Cociers OM inadetpare Meirt, _ LCO Considerstbrts ihr Select Room Cecir*s 04/21/95 9#03W

~~ ~

135 SEQUOYAH __

instrumerdshog ST trudequate Testeg, incoMoilmtrument inaccuracy No Tests ~

04/21/95 954310 :j,p...,..;Q of New Unraserne 75 h 136 SEQUOYAH 137 SOUTH TEXAS 08/24/92 92-20141 _ ._

Piping _ _ _

Heat Enchangers ST ST Corroser.

1rudequate Testeg _ anadequate Heat Transfer Teenng_Progrem

]_

138 SOUTH J.XAS 08/24/92_ 92-201 42 ; ,,,___ _ _.

Valwes,,,,,,,,, ST madequate Testeg incorrytete Inserwee Testmg Progeam_

139 SOUTH )dXAS .08/24/92 92-2C143 ., inst _rumentation ST _

fnar'equete Testing , __, Fadure to Requ.et Rehef from ASME Code R@..a._ _. _ , _

1Q ST. LUCIE 11/15/91 91-201-01L VARfOUS D .

Inaccurate _FSAR ancernpiece and inaccurale FSAR Descusses_(Sect1 2. 4L 14i ST. LUCIE 11/15/91 91-2f)142L VARIOUS OM inadequate Traming_ enedequate Tratrung Motonef _

11/15/91 tit-20143 SW PumpsIMotors

[ 142 ST. LUCIE __

ST ,

inadequate Testing ICW Pump C and Hender OperstWkty (Secte 2 4 3) 143 ST. LUC!E 11/15f91 91-23144L . Valwee _ , ,

ST _ inadequale Tes% __ inservice TesangyT) De6ciencies (Section 2,.4 4)_ _ _

144 ST. LUCtE 11/15/91 91-201-05L VARIOUS __

ST , . _ , Q M Teshng _ Preoperational Test Renew 07/06/94 644S01 ,VARIOUS _

145 SURRY _. OM _ CorrectNo Act6ons Fotow4sp on SWSOPA Correctir @. ins ,_

146 WNP-2 0 @ 01/93 93 201 01 Cootngh _ond _ , . OM _ Corrosion inadequate Evolushan of Spray r:ond Chenustryg 7 0) 147 W MP-2 .0401/93 93-201 42 Va.e2 OM Procedure th__ Fedure to perform wolve kneup in accordance seeh pre l 146 WNP-2 0401/93 93-201-03 VAR 10'T D _ inadequate Fasow.ap On cathodle Prvection Syst concems Corroston ,_-- Fadure 149 WNP-2 0401/93 9320144 Valvom D C-.-.~

p yyyqqp:n1W @ tMCF"N '* ~S" A f<

• Faaure to correct hommerly of vafwes SW-V-12A/B ' *'

' "i YN *V " "'C

~

W

• Type Designat6ons: D - Design. ST - Survedlance Testing. OM - Operations Ma6nlenance

e. e

o APPEIDIX A Table 10 sett sue 0P1 Report Examples - Types of Deficiencies or Issues SWSOPIs address all the required inspection areas of Tl 2515/118 Gemporary inspection) in detail to ar*ure themselves of adequacy in each area, and in compliance with GL8913. Exanples, taken from the NRC SWSOPI inspection reports of what has been done or vsrlf fed during these inspections include; System Desi m Verify that SWS are satisfactorily designed and capable of performing their safety fmetions Resiew design basis doctsents for SWS in their entirety Evaluate mechanical design and heat exchanger design of SWS Examine plant actions to ensure reliable performance of the SWS Review peloi SWS problem resolut ons Examine for single failure vulnerabilities and partial flow islockage in RHR Hh room coolers.

Identify thermal hydraulle performance issues that would adversely inpact ESW system capabilities verify accessibility of SWS eanually-operated containment isolation vlvs during postulated design basis conditions due to radiation.

Check for reduced margin of safety for the DG cooling water system with redJced water flow.

Verify the HPSW system is designed and maintained commensurate with its importance to safety.

Verify safety eva bations performed for changes in vlv alignment - e.g. containment air coolers.

SMtings, Setpoints, and Testing Check for inadequate testing of Pumps and valves Check for lack of baseline testing data that verifies minimun ESW flow te required loads verify procedures to assure adequate trending for H.E. degrac.ation as requit ed by GL 89-13 Verify adequacy of procedures for loss of SWS regards details of operations and checks required.

Verify a program for setpoint testing of SWS heat exchanger relief valves.

Coo 6fgurations Con *rol Documentation Verify adequate configuration control of equipment and systems Verify correct computer modeling of SWS components in the sinnalator Verify design adequacy and repeatability of SWS flow instrumentation adeouacy.

Verify design c*mtrol for instrument air supplied to A0V SWS flow control vlvs at the EDG.

Verify system drawings are accurate.

Check for discrepencies in the content of the FSARs. e.g. not updated to reflect modifications.

Incorrect licensing.and incomplete fSAR info regarding the functions of safety related system components at the time of Training Verify operation of SWS (a consistent with design requirements and procedural guidance, and that operators are properly trained.

Lack cf questioning attitude on the part of staff.

Note licensee operators knowledge of SWS requirements ar.1 capabilities.

Verify adequacy of training lesson plans Violations Determine whether authorized li9ensee activities weee conducted safetty and in accordance with NRC requirements.

Identify cited and mn-cited violathns and follow-up items required Note actual or apparent violations t,i NRC requiramemts, and institute Notices of Violations.

A-35 I

APPENDIX A Tcbi) 11 Normalized Oc:urrent Rates for cll SWS LERs by Crun C tegories, e

Year Catseery 1986 1987 1988 1989 1990 1991 1992 1993 1994 t995 T=tet A si & Sedenentanen) 4 2 4 2 7 4 7 2 5 0 37 rieseter Years 100.6 105.5 107.0 109.3 109.8 111.4 110.4 1K6 100.0 109.0 1080.5 A Events /Reactw. Years 0.04 0.019 0.I,37 0.018 0.064 0.036 0.063 0.018 0.046 0 0.34 B (Befedas) 2 4 6 3 4 1 3 0 3 5 31 Reacter. Years IK6 105.5 107.0 109.3 109.8 111.4 110.4 116 iO9.0 109.0 1000.5 B-EventsIReseter Years 0.02 0.038 0.056 0.027 0.036 (LOO 9 0.027 0 0.028 0.046 0.29 l C ICerresenIEremen) 4 2 9 5 12 5 4 7 5 5 58 Reactor Years 100.6 105.5 107.0 109.3 109.8 111.4 1114 116 109.0 100.0 1000.5 C-Events /Reacter Years 0.04 0.019 0.084 0.046 0.109 0.045 0.036 0.064 0.046 0.046 0.54 D (Dehns) 1 4 3 2 2 0 2 3 0 0 17 Reacter Years 100.6 105.5 107.0 109.3 109.8 111.4 110.4 106.6 109.0 109.0 1080.5 DfventalReacter-Yeer 0.01 0.038 0.028 0.018 0.018 0 0.018 0.028 0 0 0.16 E (P "%#el ftrors) 20 28 37 32 28 21 29 27 24 21 267 Hoector Years 100.6 105.5 107.0 109.3 109.8 111.4 110.4 IK6 109.0 109.0 1080.5 E Events /Reector-Years 0.199 3.266 0.346 0.293 0.255 0.189 0.263 0.249 0.22 0.193 2.47 F (Domen/Sennec) 16 13 24 25 16 9 19 17 19 11 169 Reacter Years 100.6 105.5 107.0 109.3 109.8 111.4 110.4 IK6 110 100.0 1000.5 Ffventsmeneter Years 0.159 0.123 0.224 0.229 0.146 0.0f? 0.172 0.157 C.174 0.101 1.57 Mechamenc(Cat. A 01 11 12 22 12 25 10 16 12 13 10 143 Rawter. Years 100.6 105.5 107.0 109.3 118 111.4 110.4 IK6 100.0 100.0 1000.5

,Medensac Events /Reacter-Years 0.109 0.114 0.206 0.11 0.228 0.09 0.145 0.11 0.119 0.092 1.32 Non40echeesec (Cat. E & F) 36 41 61 57 44 30 48 44 43 32 436 Reacter. Years 100.6 105.5 107.0 109.3 100.8 111.4 110.4 1K6 100.0 1'19.0 1000.5 Nan 41schemste Eventamenet:.r Years 0.358 0.309 0.57 0.522 0.401 0.200 0.435 0.405 0.394 0.294 4.04 Tetel Nueer of Events 47 53 83 49 ES 40 64 56 56 42 579 Reactor-Years 100.6 105.5 107.0 109.3 109.8 111.4 110.4 1K6 109.0 100.0 1000.5 Tetel EventsIReacter. Years 0.467 0.503 0.776 0.832 0.828 0359 0.58 0.516 0.514 0.305 5.36 i

i See Figere 2 for pists of indmdeel estegenes A F.

See Figure 1 for pists of the Medomsec, Non48echeesec, and Total Events.

A-36 l

APPENDIX A Table 12 - N:rmalized Occurrent Rates f t Safety Significent SWS LERs by Crum Categories, e

Year Category 1986 1987 1888 1989 1990 1991 1992 1993 1994 1995 Total A (Set & Se4mnantenen) 2 0 1 1 1 1 7 0 5 0 18 Reacter. Veers 100.6 105.5 107.0 109.3 118 111.4 110.4 108.6 100.0 109.0 1080.5 A fventameector-Years 0.02 0 0.009 0.009 0.009 0.009 0.063 0 0.046 0 0.17 8 (Basfeshes) 1 1 4 1 4 1 3 0 3 5 23

_ 'lemeter Years 100.6 105.5 107.0 109.3 109.8 111.4 1104 IK6 100.0 100.0 1980.5 B-f vents /Reacter Years 0.01 0.009 OA37 0.009 0.036 0.009 0.027 0 0.028 0.046 0.21 CICe. R '

2 0 2 2 2 0 2 3 4 4 21 Reector-years

• 00.6 105.5 107.0 109.3 109.8 111.4 110.4 100.6 109.0 109.0 1080.5 C.EventalRese:er. Years 0.02 0 0.019 0.018 0.018 0.018 ;ef 28 0.037 0.037 0 0.19 D IDebris) 0 1 2 1 1 0 0 2 0 0 7 Reecter.Yeers 100.6 105.5. 107.0 iO9.3 109.8 111.4 110.4 108.6 109.0 109.0 1000.5 O f vents"leseter. Years 0 0.0W 0.019 0.009 0.009 0 0 0.018 0 0 0.06 E (PerrennellProcedwel Errors) 3 3 2 5 4 3 2 7 6 7 42 Rectw Years 100.6 105.5 107.0 109.3 109.8 111A 110.4 108.6 109.0 109.0 1080.5 E-Eventsmeneter Yeers 0.03 0.028 0.019 0.046 0.036 0.027 0.018 0.064 0.055 0.064 ').39 F (Desse/Seesec)- 3 0 5 3 2 1 4 5 7 6 36 Reectw. Years 100.6 105.5 107.0 109.3 109.8 111.4 110.4 1K6 100.0 110 1080.5 F twentsinometer-Years 0.03 0 0.047 0.027 0.018 0.000 0.036 0.046 0.064 0.065 0.33

)

N(Cet. A 0) 5 2 9 5 8 2 12 5 12 9 69 Reector. Years 100.6 105.5 107.0 109.3 IK8 111.4 110 4 1K6 100.0 100.0 1080.5 leadienstic Ewentdteacter Veers 0.05 0.019 0.084 0.046 0.073 0.01C 0.109 OLO46 0.11 0.083 0.64 Nee.lieshamstic (Cet. E & F) 6 3 7 8 6 4 6 12 13 13 78 Reacter. Years 100.8 105.5 107.0 109.3 100.8 111.4 110.4 108.6 100.0 100.0 1080.5 hen % Events /ReacterYears 0.06 0.020 t il85 0.073 0.055 0.036 0.064 0.11 0.119 0.119 0.72 TetelNmeter of Eveets 11 5 16 13 14 6 18 17- 25 = 22 147 Reacter-Years 100.6 105.5 107.0 109.3 1K8 111.4 110.4 1K6 109.0 100.0 1080.5 Totallvestamesetsr. Years 0.109 0.047 0.15 0.119 0.128 0.054 0.183 0.157 0129 0202 1.36 Notec See Fiesre 5 for pists of the h Neo-h. and Total Events.

2 A-37 I

k .

APPENDIX A .

Tabla 13 - N::rmalized Occurrent Rites for Safety Signific:nt SWS LERs by Signific:nca Categories, ,

Year Category 1986 1987 1988 1989 1950 1991 1932 1993 19'44 1995 Total 2(ActualTotalFeNo Conditional) 1 0 1 4 1 0 1 1 0 0 9 Reactor Years 100.6 105.5 107.0 109.3 109.8 111.4 110.? 108.6 109.0 109.0 1080.5 2 Events / Reactor Year 0.01 0 0.009 0.037 0.009 0 0.009 0.009 0 0 0.08 3 (Petental Total FailwelDegr=Jation) 1 2 4 5 2 3 4 7 8 3 39 Reactor-Years 100.5 105.5 107.0 109.3 109.8 111.4 110.4 108.6 109.0 109.0 1080.5 3 Event:4teactor Year: 0.01 0.019 0.037 0 M6 0.018 0.027 0.036 0.064 0.073 0.028 0.36 4 (Actual Parnel Failure) 4 1 3 1 0 1 1 3 4 4 22 Reactor Years 100.6 105.5 107.0 103.3 109.8 111.4 110.4 108.6 109.0 109.0 1080.5 4-Events / Reactor Year: 0.04 0.009 0.028 0.009 0 0.009 0.0G9 0.028 0.037 0.037 0.21 5 (Petennal Parnal FailurelD yadaten) 0 0 0 0 1 0 2 3 4 4 14

~

Reactor Years 100.6 105.5 107.0 109.3 109.a 111.4 110.4 108.6 109.0 109.0 1080.5 5-Events / Reactor. Years 0 0 0 0 0.009 0 0.018 0.028 0.037 0.037 0.13 6 (Faile of another Systen due to SWS) 5 2 8 3 10 2 10 3 1 11 63 Reacter Years 100.6 105.5 107.0 109.3 109.8 111.4 110.4 108.6 Iv9.0 109.0 1080.5 6 Events /Reacter. Year 0.05 0.019 0.075 0.027 0.091 0.018 0.091 1 028 0.083 0.101 0.58 _

Total Number ef fvents 11 5 16 13 14 6 18 17 25 22 147 Reacter Years 100.6 105.5 107.0 109.3 109.8 111.4 11tL4 108.6 109.0 109.0 1080.5 Total Events /Rosctor Years 0.109 0.047 0.15 0.I'3 0.128 0.054 0.163 0.157 0229 0.202 1.36 Notec See Figure 7 for piet of s' ulindual categories 2 6.

A-38 1

Y