ML20057E824
| ML20057E824 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 10/06/1993 |
| From: | Westberg R, Wright G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML20057E813 | List: |
| References | |
| 50-266-93-12, 50-301-93-12, NUDOCS 9310130198 | |
| Download: ML20057E824 (26) | |
See also: IR 05000266/1993012
Text
{{#Wiki_filter:-_ _ _ - _ _ _ _ _ _ - _ _ _ _ _ - - _ _ _ , . ! U. S. NUCLEAR REGULATORY COMMISSION REGION III Reports No. 50-266/93012(DRS); No. 50-301/930!2(DRS) Docket Nos. 50-266; 50-301 Licenses No. DPR-24; No. DPR-27 Licensee: Wisconsin Electric Power Company 231 West Michigan Street - P379 Milwaukee, WI 53201 Facility Name: Point Beach Nuclear Plant - Units 1 and 2 Inspection At: Point Beach Site, Two Rivers, WI Inspection Conducted: August 2 through September 3, 1993 Inspection Team: R. Westberg, Team Leader J. Hansen, Licensing Examiner J. Guzman, Reactor Inspector M. Huber, Reactor Inspector H. Freeman, Resident Inspector, Palo Verde D. O'Neal, NRC Intern NRC Consultant: G. Cha, Engineering Planning and Management, Inc. Approved By: h /0!6[[f / , /Rolf A. Westberg, Tenm Leader Date Region III /[6![) [i / Approved By:
4 i lieoffrey C. Wiright,~ Chief Date Engineering Branch Inspection Summary Inspection on Auaust 2 throuch September 3. 1993 (Reports No. 50- 266/93012(DRS): No. 50-301/93012(DRS)) Service water system operational performance inspection (SWSOPI) in accordance with NRC Temporary Instruction 2515/118. Results: The team determined that the SWS design and operation were satisfactory. Engineering and technical support were adequate based on their involvement in the SWS design and operation. System design and engineering support strengths and weaknesses are provided in the Executive Summary of this report. One Violation wa; identified regarding failure of a special maintenance procedure to include quantitative acceptance criteria and contingency actions to mitigate the potential consequence of having equipment unavailable (Section 7.4). Two Inspection Followup Items were identified; establishment of a consistent design temperature for the SWS (Section 5.2) and licensee review of analysis methodology and acceptance criteria for performance tests (Section 5.3). 9310130198 931006 PDR ADDCK 05000266 G PDR
_ _ _ - - - _ - _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ - - . Executive Summary During the period August 2 through September 3, 1993, a Region III inspection team conducted a SWSOPI at the Point Beach Nuclear Plant. The SWS included safety related containment fan coolers, spent fuel pool heat exchangers, battery room coolers, and the diesel generator coolers. For these systems, the inspection included a focused mechanical design review; system walkdowns; review of system operation, maintenance, and surveillance; assessment of GL 89-13, " Service Water System Problems Affecting Safety Related Equipment," quality verification and corrective actions guidelines; and system unavailability. The team considered Point Beach's SWS design and operation satisfactory. In addition, the team concluded that, overall, the engineering and technical support organizations were qualified and adequately involved in SWS design and operation. The team identified the following strengths: Competent, dedicated engineering personnel.
Licensee vertical slice audit of SWS. Development, validation, and use of a SWS model.
Proactive zebra mussel control program.
The team also identified the following weaknesses: Discrepancies in piping and instrumentation drawings (P& ids) and
isometric drawing. 1 Lack of Engineering involvement and inattention to detail relative i
to performance monitoring procedures. l
Inadequate work control. l Lack of communication between licensee organizations. l
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._- _ _ _ _ _ _ _ _ _ - _ _ _ _ _ - _ _ - _ _ _ _ _ _ _ - . - TABLE OF CONTENTS Paae EXECUTIVE SUMMARY................................................. i 1.0 INSPECTION SCOPE AND OBJECTIVES............................. I 2.0 LICENSEE ACTION ON PREVIOUS INSPECTION FINDINGS............. 1 3.0 GENERIC LETTER 89-13 IMPLEMENTATION......................... 2 4.0 SYSTEM DESCRIPTION.......................................... 2 5.0 MECHANICAL DESIGN REVIEW.................................... 2 6.0 0PERATIONS.................................................. 8 7.0 MAINTENANCE................................................. 11 8.0 SURVEILLANCE AND TESTING.................................... 15 l 9.0 INSPECTION FOLLOWUP ITEMS................................... 16 10.0 EXIT MEETING................................................ 16 Appendix A - Personnel Contacted Appendix B - Generic Letter 89-13 Actio^ items l 1 1 ? < _ _____ ---__-----_-.--_---a
._. ____________ ________ _____ _ ___- DETAILS 1.0 Inspection Scope and Obiectives Numerous problems identified at various operating plants in the country have called into question the SWSs' ability to perform their design function. These problems have included: inadequate heat removal capability, biofouling, silting, single failure concerns, erosion, corrosion, insufficient original design margin, lapses in configuration control or improper 10 CFR 50.59 safety evaluations, and inadequate testing. NRC management concluded that an in- depth examination of SWSs was warranted based on the identified deficiencies. The team focused on the SWSs' mechanical design, operational control, maintenance, and surveillance. The team also evaluated aspects of quality assurance and corrective action programs related to the SWS. The inspection's primary objectives were to: assess SWS performance through an in-depth review of mechanical systems e functional design and thermal-hydraulic performance; operating, maintenance, and surveillance procedures and their implementation; and operator training on the SWS, verify that the SWS's functional designs and operational controls are e capable of meeting the thermal and hydraulic performance requirements and that SWS components are operated in a manner consistent with their design bases, assess the licensee's planned and completed actions in response to e Generic Letter 89-13, " Service Water System Problems Affecting Safety Related Equipment," July 1989, and assess SWS unavailability resulting from planned maintenance, e surveillance, and component failures. The areas reviewed and the concerns identified are described in Sections 3.0 through 8.0 of this report. Conclusions are provided after each section. Personnel contacted and those who attended the exit meeting on September 3, 1993, are identified in Appendix A. Details pertaining to GL 89-13 action items are attached as Appendix B. 2.0 Licensee Action on Previous inspection Findinas (Closed) Unresolved Item 50-266/92008-01(ORS): 50-301/92008-Ol(DRS): Discrepancies between the licensee's IST program and ASME Section XI Code requirements. This unresolved item consisted of several issues related to the various IST program requirements. The licensee addressed all concerns related to this item. No problems were noted and this item was considered closed. ) ! 1 l - - - - - - - - - -
. 3.0 Generic letter 89-13 Implementation The NRC issued GL 89-13, " Service Water System Problems Affecting Safety Related Equipment," requesting that licensees take certain actions related to their SWS. These actions included establishing the appropriate frequencies for testing and inspecting safety related heat exchangers over three operating cycles, to ensure the operability of SWSs that are credited for cooling safety ' related equipment. The team considered Point Beach's response to GL 89-13 acceptable; however, the procedures for performance testing were weak. See Section 5.3 for details. See Appendix B for details pertaining to each GL 89-13 action item. 4.0 System Description The Point Beach Units 1 and 2 SWS provides cooling water from Lake Michigan to both units through a header system. Six electric motor driven vertical turbine pumps are provided. Two of six pumps are capable of carrying the normal cooling load for the two units. Three pumps are required to operate during the injection and recirculation phases of a postulated loss of coolant accident in one unit, with a hot shutdown condition in the other unit; however, a more severe accident case is currently being investigated as a result of GL 89-13's requirement to identify single active f ailure vulnerabilities. Motor operated isolation valves are provided which are controlled remotely from the control room, and will automatically isolate nonessential services in the event of a safeguards actuation signal. The supply of SW to the essential services or safety related components is as follows: the north and south supply headers provide a redundant cooling water supply to the diesel generator coolers, auxiliary feedwater pump bearing oil coolers, component cooling heat exchangers, battery room coolers, and containment fan coolers. The west supply header routes water to containment fan coolers and spent fuel pool heat exchangers. 5.0 Mechanical Desian Review j The mechanical design review included determination of SWS design assumptions, design bases, design configurations, calculations, analyses, boundary conditions, performance tests, and computer models in fulfillment of licensing commitments, regulatory requirements, and acceptable engineering practices. ' The team also reviewed the system's seismic qualification, single active failure vulnerabilities, biofouling control program, and selected modification packages. The team concluded that SWS mechanical design was adequate and that the SWS would provide the necessary flow to the safety related heat exchangers during the design basis event. The team considers SW design temperature development and associated heat exchanger and cooler heat transfer capability assessment before summer of 1994 very important. The team considered the SWS vertical slice audit a strength. The team considered the performance monitoring test procedures unacceptable in the current state and the lack of engineering involvement a weakness. The SW model development, validation and use was ' considered a strength. 2 - - . .
I ' l 5.1 Capability of Component Coolina Water (CCW) Heat Exchanaer The team was concerned that low operating flows / velocities associated with CCW heat exchangers will cause tube side fouling, which will result in the degradation of heat transfer capability, especially toward the end of operating cycle. The design tube side SW flow was 4200gpm; however, the actual flow measured during normal operation was 325gpm to 490gpm. The original CCW heat exchangers were equipped with " Admiralty" tubing. Heavy pitting and fouling led to replacement of these heat exchangers in 1986 with i 90-10 Cu-Ni tubes. They were also retubed in 1987 with " Sea-Cure" ASTM A268, a ferritic stainless tubing material due to severe pitting. After the heat exchangers were retubed with Sea-Cure, pitting was no longer a concern, but heavy fouling continued to be observed. 1 The licensee agreed with this concern and advised that a plan was being l developed where CCW heat exchanger data would be recorded during normal and ' cooldown (which imposes the highest heat load on the CCW system) operations for trending of fouling factors and determination of heat transfer capability.
The team considered this response acceptable. 5.2 Service Water Desian Temperature The team was concerned that no consistent design temperature existed for the SWS. Safety related SWS heat exchangers and coolers were designed for a lake water temperature of 70 F or less (two used a temperature of 65 F). Other analyses used 75 F and the licensee's justification for continued operation (JCO), updated on August 3,1993, permits operation to 72 F or 76 F if the spent fuel pool heat exchanger is aligned to the "A" train. Recent temperature records indicated that some of these existing SWS design temperatures have been exceeded. The licensee also identified the need to establish a design SWS temperature in their SWS vertical slice aedit and issued comitment tracking (CMTRK) A-P-93-01, action 4, with a due date of December 31, 1994. The scope of this item included ootaining historical data regarding SW temperature, determining the SWS design temperature for the safety related heat exchangers, and updating the heat exchanger data sheets, as warranted. The heat exchangers which will be evaluated included the containment recirculation coolers, the diesel coolers, the spent fuel pool heat exchangers, and the battery room coolers. The team considered the licensee's vertical slice audit and its findings a strength but felt that the stated ccapletion time for the SWS design temperature was too long and should be revised to some time prior to the
summer of 1994 in order to assure safe operation prior to the next high lake 1 water temperature period. The licensee agreed with the team's concerns, and ' upgraded CMTRK A-P-93-01 from priority 4 to priority 3 with a due date of May 31, 1994.
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_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ __ The team was satisfied with the priority upgrade; however, pending completion and subsequent NRC review, this was considered an Inspection Followup Item (50-266/93012-01(DRS); 50-301/93012-01(DRS)). 5.3 Inadecuacies in Test Procedures While the team believed the containment fan coolers, spent fuel pool heat exchangers, and battery room coolers would perform the design functions, inadequacies in the performance test procedures for these components were identified. For example: a. The team reviewed six Containment Fan cooler tests. The test results were not repeatable. Although the calculated heat transfer capability exceeded the acceptance criteria, when these values were compared against each other, they differed by as much as a factor of 1.4. When the results were compared with the acceptance criteria, the maximum difference was in excess of +57%. This large discrepancy raised questions as to the complete test procedure's validity. In addition, the calculations showed negative fouling factors and the pressure drop calculated for a fouled cooler was less than the pressure drop for a clean cooler. No explanations were offered. b. Performance testing of spent fuel pool heat exchangers began on March 20, 1992 using PC-56 PART 3, " Performance Test for Spent Fuel Pit Heat Exchanger HX-13A." Six tests have been performed to date. The team's review of these tests identified a number of discrepancies. For example: The calculated heat transfer capability varied over a range of
, -46% to +283% as compared to the acceptance criteria, they differ I by a factor of 5.24 when compared against each other, and two of six tests failed the acceptance criteria. This variance was believed to be caused by the SW's flow rate magnitude (at lower flows, the fouling factor is greater) and uncertainties in the spent fuel pool heat exchanger inlet differential temperature (AT) measurement. Some tests have shown a fouling factor nominally 2 to 4 times
greater than the vendor specified design fouling factor. No engineering evaluation has been done to determine what action should be taken, if any, due to the observed fouling. Also, the tests show a pressure drop on the spent fuel pool water side of approximately 25 psig, which is about 5 times the design specification sheet value. This large pressure drop was seen on ! all the tests. The licensee was not aware of this. On the SW shell side, a large decrease was observed in the e pressure drop from about 20 psi in the first performance test to about 5 psi for the remaining tests. This may have been due to an error in reading the spent fuel pool heat exchanger outlet 4 - _ _ - _ _ _ _ - _ - _ _ _ .
pressure instrument, PI-2950. This instrument was replaced with a l new gauge and dampener due to excessive oscillation on maintenance work request (MWR) No. 922613 on July 15, 1992. However, the new instrument had not been calibrated and the error in the instrument, which has been used in all tests, was unknown. The licensee was aware of elevated fouling factors, but was not aware pressure drop discrepancy magnitudes. e The test procedure required all temperature indicators to be accurate to within d5% of measured AT in order to achieve an overall error of less than 10% in the heat duty at design conditions. Indicator No. TI-633A had a nominal error of 50% or more of measured oT across the spent fuel pool heat exchanger water side. The licensee responded that they propose to review and enhance the test procedure, the analytical model for extrapolation, and instrumentation requirements. A pressure device will be installed as the review dictates. The licensee recognized the widely divergent results when they were reviewed at the end of July 1993. The licensee also identified a potential source of error: spent fuel pool inlet temperature element location, and issued a MWR for corrective actions. The team agreed that this change could potentially improve the results of future tests, but considered the test procedure unworkable in its current state. c. Battery room cooler performance testing began on March 13, 1992 using PC-56, "HX-105 Battery Room Cooler Performance Test Analysis." Six tests have been performed since that time. The team's review of these tests disclosed the following: The SW outlet temperature had been measured in the incorrect place e for 5 of 6 tests, spanning the period of about a year. Also, there were continuing problems with obtaining relative humidity data. Two tests conducted in 1993 failed to meet the acceptance
criteria. In addition, both calculations contained negative fouling factors and the pressure drop for a fouled cooler was calculated to be less than the pressure drop for a clean cooler. No explanations were offered. , Four tests conducted in 1992 were all rejected by the licensee due o to errors in measurements. The licensee also determined that the computer program for extrapolation to the design basis conditions was not suitable for this type of cooler. 5 . .
The current test procedure, used a 90% reduction of overall heat transfer coefficient for an acceptance criteria. The original vendor supplied value had been modified by the licensee, without any technical justification.
Procedure reviews were not completed in a timely manner. The tests were reviewed about one year after the start of testing. The team concluded that this test procedure was unworkable in its current state. Since the start of testing in 1992, the licensee recognized the difficulties of achieving consistent results, especially associated with low temperature differentials; various revisions to the test procedures and MWRs were made in the attempt to correct the problems. However, the licensee agreed with the team's concerns and proposed to conduct a review of analysis methodology and acceptance criteria for each performance test and to document the associated basis. In addition, a complete review of instrumentation accuracies and locations as they relate to performance test results was planned. The team concurs with the licensee's attempt to improve the test procedures and test results; however, pending completion and subsequent NRC review, this was considered an Inspection Followup Item (50-266/93012-02(DRS); 50-301/93012-02(DRS)). The team also concluded that there was a lack of engineering involvement in the performance monitoring test program as evidenced by examples of non- conservatism and obvious errors in the calculations that should have been caught in the checking process and the lack of timely procedure data reviews. The team considered this a weakness. 5.5 Potential for Containment Cooler Off-Gassing The team was concerned that SW temperatures predicted at the containment coolers' outlet during the design basis accident could be sufficiently high as , to cause off-gassing. NRC Information Notice 93-12 discussed the phenomena of off-gassing. When water saturated with dissolved air is heated in plant systems, some air can be expected to evolve from the water and collect above elevated horizontal slow moving water volumes. This accumulation of air can potentially cause flow passage binding. The licensee agreed that although some off-gassing will occur, the flow would be sufficiently turbulent such that any bubbles that may form will be entrained in the flow. Furthermore, a review of piping isometrics showed that the piping runs downstream are essentially straight, with a minimum of elbows
or bends to minimize formation of gas pockets. 6
. The team concurred with the licensee's response, and was satisfied that off- gassing induced flow blockage was not expected to occur at the containment cooler outlets. 5.6 Potential for Containment Cooler Boiling )
The team was concerned that the SW temperature predicted at the containment I cooler outlet could be high enough to cause boiling if the pressure was insufficient. The licensee responded to this concern in Section 5.3.b whereby review and test procedure enhancement, analytical model for extrapolation, and instrumentation requirements will dictate if a pressure device is required. The team concurs with this response. I 5.7 Seismic Review ! ! The team found a general lack of seismic qualification for the SWSs' safety ! related portions. FSAR page A-4 stated that Class I equipment such as valves, ~ heat exchangers, pumps, tanks, motors and electrical equipment components were analyzed in one of four methods. However, valve specification No. 6118-M-90 for motor operated valves, and No. 6118-M-91 for large butterfly valves did not specifically impose seismic requirements. Further, no seismic information was available for the Zurn strainers and the SW pump motors and their associated motor control centers. The licensee advised that all SWS seismic related issues will be addressed as part of their response to Generic Letter 87-02, Supplement 1, " Verification of , Seismic Adequacy of Mechanical and Electrical Equipment in Operating Reactors, Unresolved Safety Issue (USI) A-46." The licensee submitted a response on September 21, 1992, with a scheduled summary report due date of June 1995. An NRC letter of February 22, 1993, approved the proposal. The team considered this response acceptable. 5.8 Service Water Model The SW model at the Point Beach Nuclear Power plant was based on an industry ' accepted computer program designed to model flows through piping networks. This model was implemented at Point Beach to model flows and pressure drops at i design basis accident conditions through the SW system. SW flow model results were shown to be credible by the updated computer model validation, Calc. No. N-92-087, " Service Water Computer Model Validation," done on September 10, 1992. The SW flows and pressure drops were recorded during normal plant operations using special maintenance procedure (SMP) No. 1092 and these results were compared with the results of Calc. No. N-92-087 which modeled SW flow under normal plant conditions. ! The SW flow model was based on appropriate assumptions and equations. The model has been calibrated to plant specific conditions. Correlation measurements for observed pressure drops and flow through plant SW piping and components were incorporated into the model on September 25, 1992. 7
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. i SW model reviews were done by the vendor before sending calculation results to Point Beach. Point Beach then reviewed the calculations in accordance with I quality procedure No. QP 3-6.1. The reviews were thorough. The licensee used the model to evaluate plant conditions. For example:
On February 16, 1993, the Manager's Supervisory Staff (MSS) approved a JC0 which concerned SWS operation. Calculations N-90-006, Rev.1, and i N-92-087 using the SW computer model, indicated that the containment fan i coolers may not receive the required flow under certain accident l conditions. Another calculation, N-92-054, indicated that the flow obtainable at the time would be sufficient if the SW inlet temperature was less than 63 F. Operations used a limit of 60 F as a conservative value to ensure further actions would be taken. On May 16, 1993, Operations personnel performed Procedure Nos. TS-33 and TS-34. These procedures resulted in the containment cooler throttles being set to allow more flow. The criteria was greater than 1200 gpm with 3 pumps running to ensure the required flow with only 2 pumps under > accident conditions. The Unit 2 coolers could not attain the 1200 gpm required under TS-34. A minimum flow of 1070 gpm was recorded. This corresponded with the value predicted by the model. Because the TS-34 required value could not be attained, this indicates that the required flow under accident conditions may not be reached. Therefore, JC0 93-001 remains in affect with a preliminary value of 72 F as the calculated limit. Operations uses a cut off value of 70 F to ensure actions are taken before reaching 72 F. Aligning the spent fuel i pool heat exchanger to the "A" train allow operation up to a preliminary value of 76 F. The team considered SW model development, validation, and use a strength. , 6.0 Operations The team reviewed plant operations to assess operator knowledge and the accuracy and completeness of procedures and training with regard to the SWS. The team performed system walkdowns; reviewed procedures for nonnal, abnormal, and emergency conditions; assessed conduct of operations in the field and control room; and evaluated training manuals, lesson plans, and operator actions on simulated SWS malfunctions. The team determined the licensee was operating the SWS in an appropriate manner. Plant equipment labeling was adequate and the licensee was reviewing station procedures and P&lDs to ensure discrepancies were corrected. Although some weaknesses were identified, operating procedures, operator training program relating to SWS, and operator knowledge of SWS equipment operations and procedures were considered effective. Discrepancies in the P& ids and isometric drawings were considered examples of weakness in configuration control. The failure to correct the hich AP on the Zurn strainer was considered an example of poor communication between operations and ' maintenance. \\ 8 < - -
6.1 System Confiouration Walkdowns During detailed SWS walkdowns, the team noted numerous discrepancies between the as-built SWS and the P&lDs. While several discrepancies noted on the drawings originally supplied by the licensee have been resolved by recent drawing change notices (DClis), discrepancies were found on some redrawn P&lDs and isometric drawings. The following are examples of discrepancies identified on P&lDs and isometrics: e An incorrect seismic break designation existed on P&ID M-207, Sh. 3, downstream of SW-326 (piping for the replaced spent fuel pool heat exchanger). The isometric correctly designated this section of piping as seismic.
SWS isometric P-ll3, Rev. 7, incorrectly shows the emergency diesel generator (EDG) fire sprinkler piping as non-seismic. The pipe specifications for SW-Return-From-Safeguards-Equipment piping e (spec. JB-2) was correctly shown on the isometrics but was sometimes shown as JB-1 on the P& ids. Expansion joint tio. 2973 was incorrectly shown as 2909 on SWS isometric
P-ll3, Rev. 7. Drain valve fio. SW-529 was not shown on SWS isometric P-ll3, Rev. 7.
The taps for FI-4459 A & B, and their isolation valves, were not shown
on SWS isometric P-ll3, Rev. 7. Several valves did not have caps as indicated by the P&lDs. The valve
lineup checklists did not require these valves to be capped and in some instances the valves had materials not identified on the P&lDs or checklists installed. For example, 2SW-239 had a chicago fitting installed and SW-325 had a swagelock fitting installed. SW-646 was incorrectly shown and labeled as a drain on P&lD M-207, sheet e 3. Several valves and instruments were labeled incorrectly including 1 and
2F1-2888. Although another instrument was incorrectly labeled as FI-2888, the primary auxiliary building (PAB) operators were using the correct instrument to complete OPS-31, " Auxiliary Building Shift Log." tio paperwork had been initiated to resolve this discrepancy until identified by the team. The licensee subsequently corrected the labels. SW-687A-D were incorrectly identified on the P&lDs as being locked open.
They are listed as throttled in accordance with CL-10J and PC-24 and are currently throttled in the plant. 9
The licensee agreed to incorporate all P&ID, isometric and labeling discrepancies noted by the team into their corrective action program. The team considered this response acceptable. 6.2 Operations Procedures During review of SWS procedures, the team identified several examples of weak, deficient, or inconsistent procedures. The following are examples:
The containment recirculation coolers low flow annunciator alarm setpoints were set non-conservatively at 950 gpm decreasing. The safety related flow requirement for the coolers is greater than or equal to 1000 gpm. The licensee initiated a current setpoint review and will , incorporate any required changes into their setpoint document. Procedure No. TS-33/34 set the throttle valve positions to provide
required flows to ti.e containment recirculation coolers during accident conditions. 1200 gpm was the highest indication on the instruments used to set the flow at greater than or equal to 1200 gpm. While a caution was used to ensure the instrument was not pegged or used beyond its range, the instrument's accuracy beyond its range was questionable. The licensee is evaluating replacing the instruments gauges with a larger range; however, any readjustment of throttle valves with the second return valve open would also require revalidation of flows generated with the first return valve open. The throttle valve setting for SW flow rates through the accident fan
coolers and fan motor coolers was inconsistent between operations procedures Nos. CL-10J, PC-24, TS-33/34, and 0I-72. 01-72 ind been revised since the changes were made to the other documents t . the correct numbers were not included in the most recent revis'on.
CL-10J Unit 2 was missing a note that exists in CL-10J Unit I that applies to SW-687A-D and concerns throttle valve positioning. The Zurn strainer technical manual precaution not to exceed 15 psi
differential pressure (&) across the strainer was identified in procedures Nos. 01-70 and ARB C01 A 1-5 and in training documents TRHB 11.8 and LP0086. This precaution exists to limit potential damage to the strainer element at high & s. On August 8, 1993, the Zurn strainer & for Z103 was 16 psid and had been for 2 shifts as indicated by the PAB operator's 109 The operator had circled the readings in red as they were above the alarm setpoint but nothing in the logs indicated that an attempt to resolve the current condition was being made. The team identified this concern to the licensee. The licensee determined that poor communication between operations and maintenance was the reason for slow problem resolution and initiated strainer repairs immediately. The team considered the lack of communication a weakness. Also, the precaution not to exceed 15 psi & across the strainer was not included in OPS-31 or ARB C01 A 1-60, which also respond to high & alarms. 10 . .. .-. . ,
e SW-325 was identified on the P& ids as a vent valve that should be closed. CL-10J (Unit 1) incorrectly lists this valve as a return header pressure gauge isolation that should be open.
SW-650 was listed twice in CL-10B with different locations.
SW-646 was incorrectly identified as a header drain in CL-10B. The licensee agreed to incorporate identified procedure problems into the - appropriate procedures or has resolved procedural deficiencies as discussed. The team considered this response acceptable. 6.3 Operations Scenarios /Trainino Training materials were adequate; however, one weakness was identified by the team. The replacement of SW-2930 with manual valve SW-326, although completed in 1986, the DCN was not incorporated into the training lesson plans and the lesson still documents SW-2930 as installed with the power removed. The licensee agreed to make necessary lesson plan changes. Operator responses to simulated SWS related alarms and malfunctions were effective in mitigating the events. Halfunctions responded to included an SWS line break, failure of automatic valves to reposition on a safety injection following a loss of coolant accident, inadequate flow to the containment coolers, and loss of all AC requiring manual actions to ensure cooling to the turbine driven auxiliary feed pump bearings. The operators were knowledgeable about necessary local actions and where those actions would be performed. Auxiliary operators who were interviewed were knowledgeable of procedural steps assigned to them and understood SWS function. 7.0 Maintenance The team reviewed maintenance procedures, work history, completed work request i packages, LERs, deviation reports, and preventive maintenance tasks for selected components to determine if the SW components and piping were being adequately maintained and to detect any system equipment that required frequent maintenance. The team also evaluated implementation of GL 89-13 commitments in the maintenance area. The team determined that SWS maintenance was acceptable and that the SWS was functional. The team concluded that the licensee should place more emphasis on QC's involvement with SWS maintenance. The team also considered the lack of procedural guidance for the EDG cooler replacements a weakness in the maintenance program. Failure to include contingency actions and acceptance criteria in tne maintenance procedure for the SW-9 replacement was considered a Violation. 11
1 ! $ , , 'l , 7.1 System Walkdown , ! The team noted substantial surface corrosion on various portions of _SW piping ) and components during a system walkdown. However, the licensee had previously ! implemented a program to identify and remove SW surface corrosion and to 'l preserve the components. This program determined that the corrosion did not represent a structural concern. The team reviewed the program and concluded - that it was adequate. The team noted numerous material deficiency tags hanging on the SW (and ! related systems) piping and components. Due to some deficiencies' age (some- i were_several years old), the team was concerned that the licensee did not have ! enough maintenance resources. The licensee had also identified a maintenance- i backlog during a self assessment and had prioritized-the work in an effort to ! reduce the number of outstanding items. !
~ The team also noted several minor deficiencies in SW system components. For j example, a valve gland follower that was not parallel to the valve was ! observed, dried grease was noted on several valve stems,- and there were < several valves with excessive grease and dirt on the valve packing. The team i concluded that the SWS's general material condition was below average; l however, this was also observed by the licensee in the SWS self assessment. i ! 7.2 SWS Maintenance Observation ! ! Durf ng the week of August 2,1993, while observing maintenance preparations on I valve SW-4, the team noted that two adjacent nuts had inadequate thread ! engagement of approximately 1 to 1% threads. 2 The licensee acknowledged that the thread engagement was inadequate and ! determined that this condition had existed since plant construction. The ' licensee reanalyzed the flange and determined that the flange had adequate strength to have three adjacent studs removed at the same time. The team found this response acceptable;' however, during another walkdown the I week of August 9, the team re-inspected SW-4 which had been replaced by the refurbished valve the previous week. The team again noted that two studs had ' less than full thread engagement with the flange. See Section 7.3 for -, details. 7.3 Maintenance plannino The team reviewed maintenance package preparation and found shortcomings in . l the implementation and involvement of quality control (QC) in safety related l work. , The licensee tended to rely on engineers and maintenance supervisors for quality control activities. The team's review of SW-4 replacement's work package indicated that the controlling work procedure did not ' include hold points for QC inspection. The lack of thread engagemant observed by the_ team was not identified by the engineering or maintenance personnel who supervised the work. 12 .
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. . _ _ _ _ _ _ _ _ _ _ _ - _ _ _ l . . The licensee responded that the deficiency was caused by a maintenance worker's personnel error. He did not notify the maintenance supervisor about ' the discrepancy. The licensee had previously analyzed thread engagement and determined the flange had adequate strength to have three adjacent studs
- removed at the same time. The team considered this an example of lack of communication between i individuals participating in SWS maintenance and considered the lack of QC involvement in SWS maintenance a weakness. . . 7.4 Supply Header Isolation Valve Maintenance SW-9 During replacement of a SW system header isolation valve, work was performed that was not consistent with the assumptions made in the 10 CFR 50.59 safety evaluation scope and the work procedure did not address contingem.y actions or acceptance criteria as required by licensee procedures. On July 13, 1993, the licensee replaced SW system valve SW-9 with a spool piece per MWR No. 932809. SMP No. 1136 was used to perform the work. The procedure required voluntary entry into a LC0 because SW pumps A, B, and C were isolated. Procedure No. PBNP 3.4.21, " Voluntary entry into an LCO," revision 0, dated January 15, 1993, required that the MSS authorize voluntary entry into an LCO for activities affecting multiple systems including removing more than two SW pumps from service. The procedure also required that, " contingency actions or plans that will mitigate the potential consequence of the equipment being unavailable shall be part of the considerations for activities requiring an LCO." These contingencies were required to be
addressed in the controlling work document. During SW-9 replacement, a significant amount of water beyond sump pump
capacity leaked past the boundary isolation valves. The duty shift superintendent, three engineers, a maintenance supervisor and other personnel discussed the situation and determined that since the pressure in the south header was in excess of 50 psig and since the SW inlet temperature was much i less than design temperature, work could proceed. The reasoning for continuing the maintenance may have been sound; however, since the procedure did net include any quantitative acceptance criteria for establisning "acceptaH e ieaktightness" work was performed that was not consistent with the assumptions made in the 10 CFR 50.59 safety evaluation scope. Failure to include quantitative and qualitative acceptance criteria in the maintenance procedure is considered an example of a Violation of 10 CFR 50, Appendix B, Criterion V (50-266/93012-03A(DRS); 50-301/93012-03A(DRS)). SMP 1136 also did not address contingency actions or plans that would mitigate the potential consequence of three SW pumps being unavailable as required by PBNP 3.4.21. However, the licensee reported that contingency actions had been discussed between engineers responsible for the evolution prior to work commencement and that the required material for a contingency was available. ' Failure of SMP 1136 to include contingency actions as required by PBNP 3.4.21 is considered a further example of a Violation of 10 CFR 50, Appendix B, Criterion V (50-266/93012-03B(DRS); 50-301/93012-03B(DRS)). 13 . i
- - --. - _ - . I i Based upon the actual conditions during conduct of SMP 1136, the team concluded that the modification did not represent an unreviewed safety question. 7.5 Diesel Generator Cooler Replacement The team identified several problems with the EDG glycol cooler replacement. Formal work procedures to perform the cooler replacement did not exist for EDG - G-02, they were inadequate for EDG G-01, and the evaluation performed to determine replacement heat exchanger adequacy (the replacement heat exchangers used a different tube material) was faulted. EDG G-02 cooler replacement, under MWR Nos. 913367 and 913368 on August 5, ' 1991, was accomplished without a procedure. The licensee responded that the evolution was directly supervised either by the responsible engineer or by the maintenance supervisor. The team's inspection and previous EDG test runs did not indicate any discrepancies; however, installation of safety related equipment without a procedure was considered a weakness in the maintenance program. EDG G-01 cooler replacement, under MWRs 920374 and 920375 on January 21, 1992, used a simple work plan developed from the EDG G-02 experience. This work plan did not include precautions, prerequisites, post-maintenance testing requirements, or required plant conditions. Additionally, step 12 stated in part, "do not tighten the mounting bolts," however the bolts were not required to be tightened later in the procedure. The team inspected the heat exchanger mounting bolts on both EDGs and concluded that the bolts appeared to be tight; however, installation of safety related equipment with an inadequate procedure was considered a further weakness in the maintenance program. Because the replacement heat exchangers were constructed with a different tube ' material, the licensee performed spare parts equivalency evaluation document (SPEED) No. 91-058. The replacement heat exchangers' tubes were " Sea-cure" stainless steel tubes 0.028" thick whereas the original tubes were Admiralty brass that were 0.025" thick. The stainless steel tubes had a reported thermal conductivity of 9.2 BTU /hr it oF while the brass tubes had a thermal conductivity of 64 BTV/hr ft of. The combination of a thicker tube and lower thermal conductivity reduced the replacement heat exchangers' heat transfer capability. The licensee's replacement heat exchanger acceptability analysis was flawed. SPEED No. 91-058 concluded that each replacement heat exchanger could transfer 4,760,245 BTV/hr at design conditions which were 11% greater than required. However, the analysis used a 36" tube length which was approximately 4" (11%) longer than the actual tube length. Additionally, the analysis used a fouling factor of 0.0004 hr of ft'/ BTU which was less than that of distilled water. A more appropriate value would have been to use the fouling factor for well water, 0.001 hr of ft*/ BTU. The team informed the licensee that the analysis did not justify the heat exchanger replacement when the correct values were substituted into the equation and that the heat exchangers may not be adequate. 14 .. - - .-. - - - - . - . - - -.
.-. . - The licensee reviewed the SPEED and agreed that the document was in error and that the replacement heat exchangers did not meet the design criteria. After further review, the licensee determined that the design criteria was overly restrictive. The analysis required the heat exchanger's inlet temperature on the EDG side to be s 160of. Since the EDG's normal operating range was 160of s T s 190of, the licensee determined that a more appropriate temperature would have been 190oF. The licensee contacted the heat exchanger vendor who determined, using a computer program, that with the conservative parameters, the heat exchangers would remove the required heat load. In addition, the licensee recalculated the heat transfer rate using conservative values for the tube length, fouling resistance, and EDG heat exchanger inlet temperature. The calculation concluded that the heat transfer rate was greater than the required heat removal rate. The team reviewed the calculation and agrced with the conclusions. 8.0 Surveillance and Ter ino The team reviewed preoperational test procedures, surveillance procedures, and the licensee's inservice test (IST) program and implementing procedures to determine if sufficient testing had been conducted to confirm system design requirements and system operability. 8.1 Inservice Testino of Pumos and Valves 10 CFR 55.55a required SWS components to be tested in accordance with American Society of Mechanical Engineers (ASME) inservice pump and valve testing requirements specified in the Boiler and Pressure Vessel Code's Section XI, except where relief had been granted by the NRC, or where alternative testing was justified in accordance with Generic Letter 89-04. SWS component testing concerns are discussed below. Overall, the licensee's IST program implementation was acceptable. The team identified issues related to the licensee's IST program implementation, but the issues did not detract from the overall acceptability. Based on the team's IST program review and other TS surveillances, it appeared that most SWS components were adequately tested. 8.1.1 proaram Scone The SWS IST program's scope was adequate with a few minor exceptions. These issues included: Relief valves Nos.1(2) SW-4399, SW-4367, and SW-4370 were not included
in the IST program even though they provide safety related auxiliary feedwater pump bearing cooling piping overpressure protection. Required IST included a setpoint pressure test. 15
.
Relief valves Nos. SW-4438 and SW-4440 were not included in the IST program even though they provide the safety related battery room heat exchanger piping overpressure protection. Required IST included a setpoint pressure test. Check valves Nos. FP-296A and FP-304A have an open safety function to
provide flow from the fire protection system in the event of a loss of SWS flow. These valves were not included in the IST programs' scope; however, the valves were tested in the open direction twice a year. Although the valves were tested in the open direction, the test procedure did not specify flow rate acceptance criteria to ensure that the valves would adequately perform their safety function. The licensee considered all the valves to be outside ASME's Section XI boundary. However, based on the team's concerns and given their functions within the respective safety-related systems, the licensee committed to add the components to the PBNP IST program by February 1,1994. The team considered this acceptable. 8.1.2 Pumo Testina Pump testing was in accordance with the ASME Code requirements with one minor exception. Acceptable pump performance limits for pump No. P32B contained AP acceptance limits that were incorrect. The ASME Code Table IWP-3100-2 acceptable range value for AP was .93-1.02 times the reference value or 60.38psig. The licensee's value for the low end acceptable limit was 60.23. The licensee committed to correct the AP acceptance limit. The team considered this acceptable. 9.0 Inspection Followuo items , Inspection followup items are matters that have been discussed with the licensee, which will be reviewed further by the inspector, and which involve some action on the part of the NRC or licensee or both. Inspection followup items disclosed during the inspection are discussed in Sections 5.2 and 5.3. 10.0 Exit Meetina The team conducted an exit meeting on September 3, 1993, at the Point Beach Nuclear Plant to discuss the major areas reviewed during the inspection, the strengths and weaknesses observed, and the inspection results. Licensee representatives and NRC personnel in attendance at this exit meeting are documented in Appendix A of this report. The team also discussed the likely informational content of the inspection report with regard to documents reviewed by the team during the inspection. The licensee did not identify any documents or processes as proprietary. 1 \\ 16
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, l J APPENDIX A PERSONNEL CONTACTED Wisconsin Electric Power Company Point Beach Nuclear Plant J. Link, Vice President G. Maxfield, PBNP Manager J. Anthony, Manager, Quality Assurance ! J. Reisenbuechler, Manager, Operations ! G. Krieser, Manager Industry & Regulatory Services Section i C. Gray, Operations Coordinator ' J. Becka, Manager, Regulatory Services { J. Schroeder, System Engineer (SW) F. Mueller, System Engineer (SW) D. Duenkel, Group Head, System Engineering D. Weaver, Licensing Engineer . F. Flentje, Regulatory Services T. Koehler, Manager, Maintenance Engineering i U. S. Nuclear Reaulatory Commission G. Wright, Chief, Engineering Branch i K. Jury, Senior Resident Inspector J. Gadzala, Resident inspector j K. Bristow, NRC Intern i ! i l . . . . - . - . . .. .. . -
. \\ APPENDIX B Generic letter 89-13 Action Items In a letter dated January 12,1990 (NRC-90-003), the licensee described programs either in-place or soon to be implemented to address the five actions requested in GL 89-13. The licensee subsequently submitted letters on November 15, 1990 (NRC-90-119); j January 4, 1991 (NRC-91-002); and February 27, 1992 (NRC-92-029) to advise the NRC of the implementation progress. The February 27, 1992 letter advised of the replacement of the last of the diesel generator glycol coolers, and that all actions planned in response to GL 89-13 as stated in the January 12, 1990 letter were complete. The team's review foilows: t 1. Biofoulino Control and Surveillance Technioues i Action I of GL 89-13 requested the licensee to implement and maintain an ongoing program of surveillance and control techniques to significantly reduce the incidence of flow blockage problems as a result of biofouling. In response to GL 89-13 and in anticipation of the migratory pattern of zebra mussels in Lake Michigan, an interdepartmental zebra mussel task force was formed in the Spring of 1990, one ywr prior to finding adult samples on site. The task force included members frein other Wisconsin Electric plants that have had experienced zebra mussel problems. Previous experience and lessons- learned were incorporated in the development of a site specific chlorination
program. An existing chlorination / dechlorination system is used to implement the program, which is reviewed periodically and improvements are incorporated to increase its effectiveness. Currently, the SWS receives a twice per day dosage of 52 minutes at a residual free chlorine concentration of 2 ppm. When lake water is s 45*F, the dosage and duration will remain the same but the frequency will be reduced to three times a week. During the Unit I refueling outage of Spring 1993, its portion of the SWS received a three-week continuous treatment at 2 ppm. This was intended to suffocate any adult zebra mussels that may have collected in the system. The Unit 2 portion of the SWS will be similarly treated during its refueling outage in the Fall of 1993. Continuous chlorination during refueling outage i is selected to prevent chloride intrusion at the steam generators. The diesel generator coolers (new coolers are equipped with Sea-Cure, a ferritic stainless steel tubing material highly resistant to pitting) will not be chlorinated since it is only operated bimonthly during surveillance testing, and the balance of the time there is no flow through the coolers. The licensee does not feel chlorination can be effective in light of free
. APPENDIX B 2 chlorine's short half life, and that biogrowth cannot sustain itself in an , environment that lacks oxygen and nutrients. The coolers will be inspected annually. Results of the inspections will dictate if future chlorination will be required. During the Fall 1993 refueling outage, the circulating water chlorination
injection points will be moved from the forebay to the intake crib. This will provide treatment to as much of the surfaces exposed to Lake Michigan water as possible, as well as providing a supplement to the dedicated dosages to the SWS. The licensee reviewed material compatibility with the level of chlorine concentration and concluded that there will not be any problem. The licensee installed substrates (PVC plates) in the forebay that are checked monthly during the active biofouling season (warm months) for zebra mussel attachments. Also a plankton net sampler and aquariums were installed to monitor zebra mussel veligers. Underwater inspections of the circulating water intake structure, forebay and pumphouse are conducted annually in conjunction with the respective Unit's refueling outages. Circulating water piping from the circulating water pumps to the discharge sealwell are also inspected. Most of the infrequently used pipes in the safety related portions of the SWS have full flow estatlished to them on a periodic basis during functional testing of safety related equipment. The component cooling heat exchangers were designed for 4200gpm but operate at approximately one tenth of the design flow rate; therefore, blowdown is used to control silt buildup. The chlorination, surveillance, and inspection programs appeared satisfactory in the control of zebra mussels and biofouling. The observed zebra mussel population during the active months of 1993 remained similar to that of last year. Two veliger blooms were detected this summer and were countered by increased level of chlorination. The team considered the current program sound and responsive to the GL guidelines, and should be rated a strength. However, the effectiveness of this program should be evaluated after each active biofouling period, and after heat exchangers/ coolers are either tested or inspected to determine if changes, enhancements, and modifications are required. II. Monitorina Safety Related Heat Exchancer Performance Action 11 of GL 89-13 requested the licensee to implement a test program to periodically verify the heat transfer capability of all safety related heat exchangers cooled by SW. ._ .-- -..- . -
, - . , APPENDIX B 3 4 The licensee uses a combination of testing and trending to substantiate the j heat transfer capability of the safety related heat exchangers cooled by SW.
For specific heat exchangers, they are as follows. A. Auxiliary Feedwater Pumo Bearina Oil Coolers full flow tests of the steam-driven auxiliary feedwater pumps are conducted ' monthly. Full-flow tests of the electrically-driven auxiliary feedwater pumps are conducted quarterly. Annual tests of the heat transfer capability of the ! cooling water supply to the auxiliary feedpumps are conducted in conjunction with the full-flow tests by recording bearing temperature. This method of testing was confirmed by discussions with the equipment supplier. B. Component Coolina Water Heat Exchanaers The licensee is developing an approach for recording component cooling l water heat exchanger data during normal and cooldown operations for ' trending of fouling factors and determination of heat transfer capability (see section 5.1). C. Diesel Generator Coolers , The coolers for both diesel generators were replaced. These new coolers are equipped with Sea-Cure tubes, and the engine or cooler shell side glycol has been replaced with water. Diesel operating parameters are recorded on log sheets during the bi- i weekly operability test. The diesel logs are taken three times during each operability test: prior to engine start, engine at idle speed, and when the diesel is running fully loaded for one hour. The log sheet data is then plotted for trending purposes. Tubeside fouling, hence degradation of heat transfer capability can be detected when the trending is reviewed over a given time period. D. Battery Room Coolers New coolers were installed in early 1991. Sstrumentation for performance testing completed in early 1992. Results of performance testing and analyses to-date are unacceptable (see section 5.3.c). E. Spent Fuel Pool Heat Exchancers Instrumentation for performance testing were added in early 1991. Test results and analyses to-date are unacceptable (see section 5.3.b). - , - _ , . _ - - _ _ , - . .-.I
. _ - i ! . - ( ! APPENDIX B 4 ! , l F. Containment Fan Coolers
Performance monitoring instruments were added to one of the four coolers of each Unit. Selection (Cooler D in both Units) was based on the ! lowest cooler location which is most susceptible-to silt buildup. l . The teui determined that the licensee's performance monitoring program was for l the most part unworkable. See section 5.3 for a complete discussion. III. Routine Insoection and Maintenance l l ' j Action III of GL 89-13 requested that licensees implement a routine inspection ! ! and maintenance program for open-cycle SWS piping and components. This program should ensure that corrosion, erosion, protective coating failure, t silting, and biofouling cannot degrade the performance of the safety related
systems supplied by the SWS. In the licensee's response to the GL, the licensee committed to select representative areas of the SWS based on susceptibility to corrosion, erosion and silting. These areas will be inspected to verify that the system has not , degraded and can continue to perform its safety related function. The initial inspection will be done before the end of the Unit 2 fall 1990 refueling '. outage. The representative area selected for piping supplying Unit I components will have the initial testing before the end of the Unit 1 spring i 1991 refueling. . The licensee implemented a SW Inservice Inspection Program to identify and >' monitor pipe blockage and pipe wall thinning resulting from biofouling, i corrosion products and silt buildup. Nondestructive examination, chemical addition, flushing, and hydrolancing were used in conjunction with pipe and ' component replacement. The chemical addition program included . ! chlorine / bromine injection to control biofouling. A periodic nondestructive l examination program to inspect safety related piping and heat exchangers at i known or suspected high corrosion, biofouling, or silt buildup areas was ' implemented. Visual inspections of opened heat exchangers and piping were
conducted on a scheduled basis with periodic cleaning and flushing. I I , Based on the team's review of maintenance the team considered the SWS- preventive maintenance program to be adequate to assure that safe shutdown e capability was maintained. IV. Desian Function Verification and Sinale Failure Analysis ' Action IV of GL 89-13 requested the licensee to confirm that the SWS will t perform its intended function in accordance with the licensed basis for the plant. This confirmation should include a review of the ability to perform required safety function in the event of failure of a single active component.
To ensure that the as-buin system is in accordance with the-appropriate ' licensing basis documentation, this confirmation should include recent- (within the past two years) system walkdown inspections.- ' l ' ' ! . 7w+-- w ~ q , -- ,- , , , , .~ ,-e,,--,w.+m,-e,-- , e ,,w-,.ww, ., n. v er +,,-oe-,.-n-nos-,m.a
.. i ~ . I APPENDIX B 5 A. Sinole Active Component Failure Analysis " Single Active Failure Analysis Report for the PBNP Service Water System" prepared for Wisconsin Electric Power Company, Point Beach Nuclear Plant, Revision 0, dated June 25, 1993 was performed at the component level for the identified design basis accident coincident with a loss of off-site power. In addition, two common mode failure studies identified the failure of diesel generator G02 to be most limiting; and the failure of instrumant air system was postulated. This study concluded that for each postulated single active component failure, the safety function of the SWS can be met. The team concurred with the above conclusion. B. Most limitino Accident Scenario Calculation N-90-006 Rev. I dated 9/25/1992 identified the most limiting case to be a lost of coolant accident in Unit 2, loss of off-site power, and diesel generator G02 fail to start. Failure of G02 causes four of , the motor operated isolation valves in the SWS to fail-open. Calculations showed that the most restrictive equipment with respect to receiving necessary SW flow are the containment fan coolers. Furthermore, calculations indicated that by fully opening the cooler outlet throttle valves and aligning the spent fuel pool heat exchanger to the "A" train, sufficient SW can be made available to all of the safety related heat exchangers, even with only two SW pumps operating. The team concurred that sufficient SW will be available under the most limiting accident scenario. C. Computerized Hydraulic Mocel The licensee successfully adapted a commercially available computer program to model the flow and pressure drop of SW at the various locations of the SWS. , < The computerized SW model utilized the Hazen-Williams relationship for prediction of pipe friction losses. Actual flow measurements were usec j to develop the pipe roughness factor "C", and an equivalent length for piping, fittings, and heat transfer devices. Results from the model compared well with actual naase rements of flow and pressure drop. The team reviewed the te alc0 aasis for the model, the calibration and verification results, ar
- anc'aded it will provide sufficiently
' accurate flows and press . cops for the SWS. The team considers the , development of the hydraulic model a strength. i
i i . . j APPENDIX B 6 D. Walkdowns The small bore piping of the SWS was walked down in the Fall of 1988 as part of the computer model verification program. Walkdowns of the large-bore, supply-side piping of the SWS were completed in January 1990 as part of the reanalysis for the IEB 79-14 program. In limited walkdowns conducted by the team, it appeared that the hydraulic circuits agree with the P&ID's. However, the team found minor inconsistencies when P& ids and piping isometrics were compared with actual field installations. V. Trainina Action V of GL 89-13 requested that licensees confirm that maintenance practices, operating and emergency procedures, and training that involves the SWS were adequate to ensure that safety related equipment cooled by the SWS will function as intended and that operators of this equipment will perform effectively. Licensee commitments to this item included the review of all procedures and training relating to the SWSs for accuracy and applicable experiences described in NUREG-1275 Vol. 3. ' Based on the team's review of maintenance practices, operating and emergency procedures, and training documentation, the team concluded that overall, Action V was approprictely accomplished. i l , l - }}