IR 05000528/1992036
| ML20126B928 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 12/04/1992 |
| From: | Royack M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | |
| Shared Package | |
| ML20126B887 | List: |
| References | |
| 50-528-92-36, 50-529-92-36, 50-530-92-36, NUDOCS 9212220280 | |
| Preceding documents: |
|
| Download: ML20126B928 (28) | |
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U. S. NUCLEAR REGULATORY COMMISSION
REGION V
Report Nos.
50-528/92-36, 50-529/92-36, and 50-530/92-36 f
Docket Nos.
50-528, 50-529, and 50-530 License Nos.
NPF-41, NPF-51, and NPF-74 Licensee Arizona Public Service Company P. O. Box 53999, Station 9012 Phoenix, AZ 85072-J999 Facility Name Palo Verde Nuclear Generating Station Units 1, 2, and 3 Inspected at:
Palo Verde Nuclear Generating Station, Wintersburg, Arizona Inspection date:
October 19 through 23 and November 2 through 6, 1992 Inspectors:
C. Clark, Reactor Inspector, Region V D. Acker, Reactor Inspector, Region V H. Freeman, Reactor Inspector, Region V
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Approved by:
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M. Royack, Act4hg Chief Dats Signed Engineering Section Inspection Summary:
Inspection durina the oeriod October 19 - November 6.1942 (Recort Nos 50-528/92-36. 50-529/92-36 and 50-530/92-lEl Areas inspected: This inspection reviewed the licensee's program for inservice testing (IST) of check valves in safety-related systems, the performance of Unit 3 inservice inspections (ISI), and verified completion of previously identified open items.
Temporary Instruction 2515/110 provided guidance for the inspection of check valves.
Inspection Module 73753 provided guidance for the inspection of the performance of inservice inspections.
Inspection Modules 37700, 92701 and 92703 and Temporary Instruction 2515/111 provided guidance for the followup of previously identified items.
Safety Issues Manaaement System (SlHSl_Iten:
SIMS Issue Number GL 89-04 [ Multiple Plant Action (MPA) Item Number A025]
Results:
9212220280 921204 PDR ADOCK 05000528
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RDeral Conclusions gnd Specific Findinas:
The licensee had implemented a comprehensive and aggressive e. heck
valve visual and non-intrusive preventive maintenance program.
The licensee omitted two Boric Acid check valves from their 151
program and thus had not performed the testing required by Section XI of the ASPE Boiler and Pressure Vessel Code for them.
The licensee had not incorporated reverse flow testing of certain
safety check valves in a timely manner.
The licensee had not properly documented nonconforming conditions
identified in a steam generator system check valve.
The licensee had not performed check valve examinations per
procedure instructions.
The licensee had not properly documented a snubber rejected during a
visual examination.
The licensee had not kept their program procedures for check valve
inspections up-to-date.
The weaknesses and violations identified during this inspection
appear to indicate a lack of management oversight of the implementation of your check valve program.
Sinnificant Safety Matt. qts:
None.
Summary of Violation or Deviations:
In the areas inspected three violations were identified:
A.
One violation of Technical Specification 4.0.5, implementation of Section XI of the ASME Boiler and Pressure Vessel Code. The licensee omitted required boric acid check valves from the Inservice Testing Program and thus failed to perform the required testing (Section 2.4.1.3).
B.
One violation of 10 CFR Part 50, Appendix B, Criterion XVI, Corrective Actions.
The licensee failed to properly document and evaluate nonconforming conditions found in an Auxiliary Feedwater system check valve (Section 2.4.8.1) and a snubber rejected during an inservice inspection (Section 4.3).
C.
One violation of Technical Specification 6.8.1, implementation of I
procedure identified check valve examinations.
The licensee' failed i
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to examine all check valve internal parts and surfaces (Section 2.4.8.2).
Open Items Summary:
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One followup item was opened (See Section 2.4.1.4).
Seven open items were closed. Temporary Instruction 2515/111. " Electrical Distribution System functional Followup Inspection" was also closed. All Electrical Distribution System functional Inspection (Report 90-42) open items are now closed.
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Detail s 1.
Persons Contacted Arizona Public Services Company
- G. Overbeck, Director, Site Technical Support J. Bailey, Director, Nuclear Engineering E. Dotson, Director, Procurement Engineering and Projects
- R. Fullmer, Manager, Quality Assurance and Monitoring
- D. Garchow, Manager, Site Technical Support
- B. Ecklund, Manager, Nuclear Industry Affairs
- A. Fakhar, Supervisor, Nuclear Engineering
- T. Weber, Supervisor, Performance Engineering
- R. Browning, Site Technical Support Engineer
- D Hansen, In-Service Inspection Engineer
- C. Corcoran, Plant Engineer
- B. Lindenlaub, Pump and Valve Engineer
- H Krause, Pump and Valve Engineer
- R. Roehler, Supervisor, Licensing
- R. Rosen, Quality Assurance and Monitoring Technical Specialist
- R. Fountain, Supervisor, Quality Assurance and Monitoring
- E. Dutton, Supervisor, Quality Control
- J. Bergstedt, Quality Assurance and Monitoring Technical Specialist
- B. Lehman, Component Monitoring Engineer
- J. McCoy, Maintenance Standards Advisor D. Oakes, Component Monitoring Engineer Others
- R. Henry, Salt River Project Site Representative
- F. Gowers, El Paso Electric Site Representative
- J. Draper, Southern California Edison Site Representative U. S. Nuclear ReaulatorY Commission
- D. Acker, Reactor Inspector
- F. Ringwald, Resident Inspector
- C. Clark, Reactor Inspector H. Freeman, Reactor Inspector The inspectors also held discussions with other licensee and contractor personnel during the course of the inspection.
- Denotes those attending the exit meeting on November 6, 1992.
2.
Check Valve ActivitieLJTl 2515/110)
2.1 Check Valve Backaround NRC regulations and the American Society of Mechanical Engineers (ASME)
Code require that check valves be periodically tested in a manner that provides assurance of their performance. Events involving safety-related I
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check valves, including the water hammer event at San Onofre Nuclear Generating Station (SONGS) in 1985, demonstrated to the NRC staff that additional inspection effort should be dedicated toward the review of licensee check valve programs against NRC and ASME Code requirements.
On August 29, 1988, the NRC issued Information Notice (IN) 88-70, " Check Valve Inservice Testing Program Deficiencies." This IN described the result of inspections of check valve activities at several nuclear power plants. These inspections found that some check valves within Inservice Testing (IST) programs were not being tested in a manner that verified their ability to perform their safety-related functions.
On April 3, 1989, the NRC issued Generic letter (GL) 89-04, " Guidance on Developing Acceptable Inservice Testing Programs." This GL provided clarification of ASME Code requirements in an effort to assist licensees in correcting deficiencies that the NRC had found in IST programs. The minutes of a public meeting, held by the NRC, provided detailed information on the implementation of the GL, As part of an action plan to inspect licensee's check valve IST activities, the NRC developed Temporary Instruction (TI) 2515/110,
" Performance of Safety-Related Check Valves," to assess the effectiveness of licensee check valve programs.
2.2 Check Valve Inspection Plan The inspectors used TI 2515/110 to develop an inspection plan for the check valve program at Palo Verde Units 1, 2, and 3.
The purpose of the inspection was to verify that the licensee had a program in place to ensure the operational readiness of check valves in safety-related systems.
During the inspection, the inspectors: 1) conducted an in-depth review of a sample of check valves to verify the implementation of an acceptable testing program, 2) reviewed corrective and preventive maintenance activities, 3) determined the extent of the licensee's design application.
reviews, 4) performed system walkdowns, 5) reviewed the adequacy of check valve failure trending and subsequent corrective actions, and 6) assessed the degree of licensee management involvement in the development and implementation of the check valve program.
2.3 General Comments on Check Valves Generic Letter 89-04 listed Palo Verde Units 1, 2 and 3 in Table 2.
Plants listed on Table 2 of the GL had NRC Safety Evaluation Reports (SERs) approving their IST programs at the time GL 89-04 was issued.
The NRC issued the SER (TAC Numbers 64953, 64954, and 64955) for Palo Verde Units 1, 2 and 3 on November 15, 1988.
Generic Letter 89-04 did not require Table 2 plants to review their IST programs for conformance to i
GL 89-04 since the information contained in the GL was used during the
reviews of the SERs.
However, the NRC concluded that Table 2 plants,
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including Palo Verde, should review their procedures to ensure their l
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consistency with the provisions of the generic letter, as noted in the Minutes of the Public Heeting to Discuss GL 89-04, dated October 25, 1989, page 4.
Generic Letter 89-04 contained guidance for_ Table 2 plants to use for any modifications to their approved IST programs.
2.4 theck Valve Proaram Review 2.4.1 Scope The inspectors reviewed the scope of the licensee's check valve program to verify that it complied with GL 89-04 and IST criteria.
The inspectors' findings are summarized in the following paragraphs.
Palo Verde's check valve program consisted of two parts. The first part was the American Society of Mechanical Engineers (ASME) Code Section XI IST requirements. The second part was preventive maintenance activities for selected check valves in safety-related systems, developed to the guidelines of the Institute of Nuclear Power Operations (INPO) Significant Operating Experience Report (50ER) No. 86-03, " Check Valve Failure or Degradation."
2.4.1.1 ASME Code Section XI Inservice Testina Proaram The licensee's ASME Code Section XI IST program for Unit 3 was documented in procedure 73PR-3X101, Revision 00.06, "PVNGS ASME Section XI Pump and Valve Inservice Testing Program, Unit 3."
Units 1 and 2 had similar procedures.
Licensee procedure 73PR-3XIO1 was issued to identify the components to be tested in compliance with the rules and regulations of 10 CFR 50.55a and Section XI of the ASME Boiler and Pressure Vessel Code, 1980 Edition, Winter 1981 Addenda.
Procedure 73PR-3X101 included 137 check valves.
four of the 137 check valves had relief requests approved which allowed visual inspection as a method for satisfying full flow testing criteria, The inspectors considered that the program's low number of check valves which substituted visual inspection for testing was a program-strength.
2.4.1.2 Preventive Maintenance Proaram
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Procedure 73AC-0X103, Revision 01.02, " Preventive Maintenance of Check Valves," contained the licensee's check valve preventive maintenance program.
i The licensee selected valves for this program based on INP0 guidelines; Electric Power Research Institute (EPRI) Report NP-5479, l
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" Application Guidelines for Check Valves in Nuclear Power Plants,"-
criteria; and study 13-MS-A24, Revision 3, " Check Valve Evaluation l-
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Program for PVNGS," guidelines. A discussion of the licensee's selection process is contained in Section 2.4.4.
Procedure 73AC-0X103 included 213 check valves per unit. The licensee classified each check valve based on potential failure criteria and then assigned an inspection frequency. Overall, the procedure required the licensee to:
Disassemble and inspect 43 check valves per unit over a three
refueling outage period.
Disassemble and inspect 12 other check valves per unit over a
four refueling outage period.
Disassemble and inspect one of each of 31 families of similar
valves containing a total of 158 other check valves per unit over a four refueling outage period.
Increase the scope of inspections based on unacceptable
findings in the inspections detailed above.
Ninety nine of the check valves in the preventive maintenance program were also in the. IST program.
2.4.1.3 P' view of Check Valve Proaram Scone The inspectors reviewed the check valve IST and visual inspection programs. The results of this review are discussed in the following paragraphs.
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IST Proaram - Boric Acid Check Valves The inspectors reviewed the scope of the licensee's IST program and identified that the boric acid make-u) pump discharge check valves (CHN-V154 and CHN-VISS) were not in tie IST program.
Licensee drawing number 13-M-CHP-002, Revision 31, "P and 1 Diagram Chemical and Volume Control System," identified valves CHN-V154 and CHN-VISS -
as Class "QlC."
Class Qlc was the licensee designation for safety related, seismic Class 1, ASME Class 3 equipment. These valves were in the boron injection flow path described in Technical Specification 3.1.2.2.c and tested per procedure 41ST-lCH04, Revision 2.03, " Boron-Injection Flow Test 4.1.2.2.1.b".
The flow path of this test utilized gravity feed from the refueling water tank through valve CHV-164 (boric acid filter bypass valve) and a charging pump to the reactor coolant system.
However, the flow path was paralleled through check valves CHN-V154 and CHN-VISS.
Since these check valves were required to open they were active check valves which required individual testing in accordance with the requirements of Section XI of the ASME Boiler and Pressure Vessel Code.
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The inspectors identified this program omission to the licensee.
The licensee issued Condition Report / Disposition Request (CRDR) 9-2-0679 to add valves CHN-V154 and CHN-V155 to their IST program.
This same CRDR also identified that other valves in this flow path would be evaluated for addition to the IST program.
Section 1.1 of Revision 00.06 of licensee procedure 73PR-3X101 stated in part that, "The purpose of the Palo Verde Nuclear Generating Station Pump and Valvo Inservice Testing Program is to identify the components to be tested in compliance with the rules and regulations of the 10 CFR 50.55a and Section XI of the ASME Boiler and Pressure Vessel Code, 1980 Edition, Winter 1981 Addenda."
The failure to include valves CHN-V154 and CHN-V155 in the IST program and to perform the required Section XI ASME Code testing is a violation (50-528/529/530/92-36-01).
IST Proaram - Other Check Valves The inspectors reviewed UFSAR Table 3.9-27. " Listing of Non-CE Supplied Active Check Valves ASME Class 2 and 3."
The inspectors identified that five check valves listed in Table 3.9-27 were not in the licensee's ASME Section XI test program.
The licensee determined that the five valves in question were not active ASME Section XI check valves.
The licensee issued an Engineering Evaluation Request to correct UFSAR Table 3.9-27.
The licensee had previously Jerformed a technical evaluation of these valves and concluded t1at they did not require testing.
The licensee provided this evaluation to the -inspectors.
The inspectors reviewed the licensee's evaluation and concluded that the evaluation was adequate to demonstrate that the five valves in question were not ASME Section XI active check valves.
Visual Inspection Proaram The inspectors noted that in 1990, Revisions 2 and 3 to Study 13-MS-A24, " Check Valve Evaluation Program for PVNGS," had deleted four check valves from the check valve preventive maintenance program and added 52 check valves per unit. These changes were not included in procedure 73AC-0X103.
The licen:ee determined that two of the four check valves removed from the program had no safety
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function and that the other two were inspected and showed no wear or damage. The licensee's check valve engineer stated that the latter two valves would not be totally removed from the program, but would be placed in a grouping of valves which would be inspected infrequently.
The inspectors noted that the check valve engincer was maintaining a log of check valve preventive maintenance. The log included the changes made by Revisions 2 and 3 to Study 13-MS-A24.
The log also
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included 2 additional check valves per unit not contained in either Study 13-MS-A24 or procedure 73AC-0X103.
Procedure 73AC-0X103 required one check valve from each of 31 families of check valves be inspected at least once every four refueling outages. However, Study 13-MS-A24 identified for inspection, at least once every four refueling outages, 33 families of valves and an additional 18 individual valves, which could not be grouped into a family of similar valves. Therefore, the study specified 20 more valve inspections than did procedure 73AC-0XIO3.
The inspectors noted that 208 check valve disassembly inspections had been completed as part of procedure 73AC-0X103.
In addition, 23 check valves had been non-intrusively tested. The licensee planned to inspect 35 check valves during the current Unit 3 outage.
Corrective maintenance was performed in 47 of the 208 check valves that were disassembled and visually inspected. The licensee stated that some of the corrective maintenance was minor and would not have affected valve operability.
The licensee also stated that more frequent inspections of selected check valves was being accomplished, based on the problems noted.
For example,12 check valves (four check valves in each unit) were being inspected every refueling outage.
The licensee's check valve engineer stated that he was choosing the valves to inspect each outage based on the program requirements and previous inspection results.
However, the inspectors determined that the licensee's program did not have a documented basis for revising the scope of inspections.
2.4.1.4 Conclusions The inspectors concluded that procedure 73AC-0X103 did not accurately reflect the check valves being actually worked as part of the check valve preventive maintenance program and that inspection scope changes were being done informally.
The inspectors discussed this conclusion with the licensee. The licensee agreed that procedure 73AC-0X103 required revision to accurately reflect the check valves being worked and provide a method for documenting scope changes.
The licensee stated that, based on the current schedule and the low number of problems identified, the minimum check valve inspections required by Study 13-MS-A24 would not be completed. The licensee noted that an informal review of the inspection results to date indicated that the conditions of most valves were the same in all three units and could be grouped for inspection into a family, in lieu of being individually inspected in each unit.
The licensee committed to revise procedure 73AC-0XIO3 by January 4, 1993.
The inspectors concluded that the licensee's check valve program
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scope was acceptable. Other program findings are discussed in the l
following sections.
Since the continuing adequacy of the licensee's
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check valve program depends on the comitted revision to )rocedure 73AC-0XIO3, NRC review of this revision will be accomplis 1ed as part of a followup item (Followup Item 50/528, 50/529, 50-530/92-36-02).
2.4.2 Industry Exoerience and Licensee's Check Valve Proaram Assessment The inspectors reviewed a sample of the licensee's evaluations of check valve industry experience, and vendor and NRC information documents.
The inspectors determined that the design study included industry experience. The inspectors determined that the licensee was maintaining check valve industry contact through the NIC.
2.4.2.1 NRC Information Notice 88-70. " Check Valve Inservice Testina Proaram Deficiencies" NRC Information Notice (IN) 88-70 reported that several licensees were not testing all active safety check valves, particularly parallel pump discharge check valves, in their required safety positions.
S)ecifically, the NRC noted failure to reverse flow test a number of cieck valves which were required to close as a safety function.
NRC IN 88-70 noted that Section XI of the ASME Boiler and Pressure Vessel Code required testing in the open or closed position (or both), as necessary, to verify the valve's safety function.
The licensee accomplished technical review of NRC IN 88-70 and concluded in 1989 and 1990 that a number of active check valves were not being tested in their closed safety direction. The licensee considered that the testing of these valves in the closed direction
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was an enhancement since the NRC had already approved their Section XI testing program. However, the NRC publicly stated that Table 2 plants, like Palo Verde, should review their procedures to ensure their consistency with the provisions of GL 89-04, as noted on page 4 of the Minutes of the Public Heeting to Discuss GL 89-04, dated October 25, 1989.
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In 1991, the licensee scheduled preparation of the procedures for testing these check valves by 1996. The check valves the licensee identified as requiring reverse flow testing in the closed direction included the auxiliary feedwater (AFW) pump discharge check valves, the high pressure core spray discharge check valves, the low pressure core spray suction check valves (the discharge valves were also not being tested in the closed direction), and the turbine driven AFW pump steam inlet check valves.
In 1992 the licensec's quality assurance (QA) organization performed an assessment of the check valve program. The QA organization concluded that the action on NRC IN 88-70 was untimely since NRC IN 88-70 and Generic Letter 89-04 both noted that testing of active check valves in their closed safety direction was an original requirement of the ASME Section XI Code.
Based on the QA finding,
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the licensee committed on July 9, 1992, (prior to this inspection)
to issue the necessary procedures by the end of 1992.
The licensee informed the inspectors that the subject check valves would be tested in their closed direction in Unit 3 during the present 3R3 outage. The licensee committed to test the subject check valves in Units 1 and 2 during their next refueling outages, IR4 and 2R4.
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The inspectors concluded that the licensee's actions on NRC IN 88-70 were adequate but had not been timely until the 1992 QA audit.
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2.4.2.2 fBC Information Notic L90-79. " failure of Main Steam Isolation Check yllves RetylijiAq in Disc Separation" The licensee reviewed NRC IN 90-79 and concluded that they did not have this type of main steam isolation check valve.
However, the licensee noted that similarly designed valves were installed as Extraction Steam Bleeder Trip Valves (BTVs). The licensee concluded that the BTVs should be inspected and noted that the BTVs had been added to their check valve program.
The inspectors reviewed the licensee's check valve program and noted that the BTVs were not included. The licensee issued an Engineering Evaluation Request to resolve inspection of the BTVs. The licensee provided information to the inspectors which demonstrated that several BTVs had been disassembled and inspected by the turbine system engineer, outside of the check valve program.
The inspectors concluded that the licensee's actions based on their review of NRC IN 90-79 were inconplete, in that they stated that the BTVs had been included in the check valve program, which had not been done. Based on the fact that several BTVs had been disa sembled and inspected, the inspectors concluded that there was no immediate safety concern due to this event.
2.4.2.3 NRC Information Notice 89-62. " Malfunction of Bora-Warner Pressure Siglionnet Check Valves Caused by Vertical Misaliagmipt of Disc" The licensee reviewed NRC IN 89-62 and concluded that no action was required since their vendor technical manual already included the subject infe;mation.
During the inspection, the 1 4ense0 identified to the inspectors that their NRC IN 89-62 evaluation wTs incorrect. Their vendor technical manual had not included the subject information at the time of the original review. See Section 2.4.2.4 for further discussion of NRC IN 89-62.
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2.4.2.4 Vendor Check Valve Technical Manual Updates NRC :nspection Report 92-23 discussed imsroper horizontal assembly of Borg-Warner bonnet hung disc check vaives at Palo Verde. The licensee had recently discovered that two of these valves had been assembled with the bonnet horizontally turned, preventing the disc from closing under reverse flow.
After correction of the horizontal error, the licensee reassembled the last valve in late March,1992.
The inspector identified that the vendor technical manual contained a vertical measurement to ensure the bonnet was properly assembled.
The inspector also identified that the licensee's Borg-Warner check valve reassembly procedure, performed in late March,1992, did not contain this measurement.
Subsequent to the issuance of NRC Inspection Report 92-23, the licensee issued instructions to ensure proper Borg-Warner check valve bonnet assembly in accordance with the Borg-Warner manual.
The lic.ensee determined that the bonnet was properly assembled.
During their review of the root cause of the failure of their procedure to include the technical manual vertical measurement, the licensee determined that NRC IN 89-62 discussed assembly of this check valve type and provided instructions for making the vertical measurement. The licensee determined that their review of NRC IN 89-62 was incomplete as discussed in Section 2.4.2.3.
The inspectors determined that the vendor had issued instructions to measure for proper bonnet assembly in 1990.
The licensee's vendor contact organization determined on April 9, 1991, via their routine vendor contact program, that the Borg-Warner technical manual had been updated. However, as of March 26, 1992, the planning organization which prepared iheck valve reassembly procedures, had not been notified of this change.
The inspectors concluded that the licensee's program to update the Borg-Warner check valve technical manual had been untimely based oa its failure to account for information received in April 1991.
NRC IN 89-62 also contained the vertical alignment inr'ormation, but this information was missed by the licensee due to an. incomplete review of NRC IN 89-62.
2.4.2.5 Conclusion The inspectors concluded that review of industry and vendor gentr'c information had been weak. The licensee acknowledged the inspectors' conclusion. The licensee stated that their program for review of NRC ins had been recently consolidated within the licensing organization.
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2.4.3 Manaaement Support and Oversicht The inspectors met with the licensee during the first week of the inspection to ascertain the current status of the licensee check valve program.
In addition the inspectors reviewed documents and interviewed licensee personnel to assess the degree of management support and oversight of the licensee's check valve activities, programs and their implementation.
2.4.3.1 Manaaement Suppg1 The inspectors identified the following background information relating to management support of the present check valve program for Palo Verde Units 1, 2 and 3:
In March 1989, the licensee became a charter member of the
Nuclear Industry Check Valve Group (NIC). The licensee had remained active in NIC, had hosted a NIC conference and wa:
preparing a report for the next NIC conference.
In late 1989, the licensee began implementation of INP0
SOER 86-03. The licensee began check valve visual inspections in 1990 and has performed approximately 260 check valve inspections to date. These inspections required the support of technical, maintenance, operational and radiation protection-personnel.
In June 1990, the licensee assigned a check valve engineer to
oversee check valve activities at Palo Verde.
The licensee had maintained the check valve engineer position continuously to date.
The inspectors concluded that the above actions indicated management, technical, and financial support of the check valve
inspection program.
2.4.3.2 Manaaement Oversiaht
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l The inspectors identified the following background information relating to management oversight of the present check valve program for Palo Verde Units 1, 2 and 3:
Programmatic documents were not being kept current (See Section
2.4.1.4).
The licensee took a year to process a vendor check valve manual
change (See Section 2.4,2.4).
Licensee action on NRC TN 88-70 was not timely (Self-identified
as noted Section 2.4.2.1).
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The licensee's evaluation of NRC IN 89-62 was incorrect (See
Section 2.4.2.3).
The licensee's evaluation of NRC IN 90-79 committed to
corrective action which was not taken (See Section 2.4.2.2).
Based on the above information the inspectors concluded that management oversight of the check valve inspection program could be improved. The licensee acknowledged the inspectors * conclusion.
2.4.4 Desian Aeolication Review The inspectors reviewed the licensee's program for check valve inspections contained in Study 13-MS-A24, Revision 3, " Check Valve Evaluation Program for PVNGS."
The inspectors determined that the licensee selected check valves for this program based on INP0 guidelines; Electric Power Research Institute (EPRI) Report NP-5479, " Application Guidelines for Check Valves in Nuclear Power Plants," criteria; industry information; and Palo Verde operating experience.
The licensee included the seven systems recommended by EPRI and expanded the review to include 16 additional systems.
The licensee reviewed 1380 check valves for inclusion in the inspection program, of which approximately S6 percent were recommended for periodic inspection.
The inspectors selected several check valves that were in the licensee's IST program but were not in their periodic inspection program. The inspectors reviewed the licensee's corrective maintenance for these check valves and similar design check valves.
The inspectors did not identify any significant maintenance problems with these valves which would warrant their addition to the inspection program.
The inspectors reviewed system drawings for the Safety Injection and Diesel Generator Air Start systems. The inspectors did not identify any safety significant check valves which were not in the licensee's check valve ir.spection program.
Based on the inspectors' sampling discussed above and the licensee's action to sigc.lficantly expand the scope of the inspections recomended by EPRI, the inspectors concluded that the scope of the study was adequate.
The inspectors noted two potential problems with the details of the study which are discussed in the following sections.
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2.4.4.1 System Pressure Ratina
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Study 13-MS-A24, page 50, noted that 13 check valves required
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evaluation as to whether they met the system pressure criteria.
The licensee noted that the evaluation had not been completed.
During the inspection the licensee presented a preliminary calculation which determined that the 13 check valves met their required system pressure criteria.
The inspectors reviewed the preliminary calculation and concluded that the calculation was adequate to demonstrate that the 13 check valves met their system pressure criteria.
2.4.4.2 Flow Velocity Calculations The licensee calculated the minimum flow velocity through each check valve required to provide full disc lift. The licensee used equations within-the guidelines provided by EPRI and discussed in NUREG 5159, " Prediction of Check Valve Performance and Degradation in Nuclear Power Plant Systems," and NUREG 5583, " Prediction of.
Check Valve Performance and Degradation in Nuclear Power Plant Systems -- Wear and Impact Tests." The licensee then compared the calculated minimum flow velocity that would provide full disc lift with calculated system operational flow. -The licensee assigned less frequent inspections for check valves where actual system flow was calculated to hold the disc fully lifted (backseated).
Industry information indicated that fully backseated valves were normally subject to less wear.
The inspectors noted that. testing described in NUREG 5583 indicated that the calculational method used by the licensee was
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non-conservative for swing check valves with discs which did not protrude sufficiently into the flow path. NUREG 5583 demonstrated non-conservative calculations for valves with a Y/D dimension of less than or equal to 0.25.
The Y/D dimension is shown in Appendix A of this report. The test results were shown in NUREG 5583, Figure 29.
The inspectors provided the NUREG 5583 information to the licensee.
The inspectors noted that swing check valves, calculated by the licensee as backseated and assigned a low inspection frequency, may experience disc oscillation and tapping of the backseat due to the non-conservative calculation discussed above.
Disc oscillation and tapping of the backseat could warrant more frequent inspections.
During the inspection, the licensee reviewed the NUREG 5583 information concerning minimum velocity calculations. The licensee decided not to attempt to determine which check valves had a Y/D dimension of less than or equal to 0.25.
Instead, the licensee decided to increase the inspection frequency of all swing check valves, which were originally assigned a low frequency of inspection
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based on flow calculations which predicted that the valve disc was backseated. The licensee committed to inspect at least one of these swing check valves in every application in at least one unit, by the end of the next refueling outage (2R4) of Unit 2.
The licensee noted that sor..e of the inspections could be done non-intrusively.
The inspectors concluded that reviewed the licensee's commitment to increased inspection frequency adequately resolved the potential effect of the non-conservative calculation.
2.4.5 Check Valve Testina Proaram The inspectors reviewed a sampi of check valves in several Palo Verde plant systems to determine; 1) the adequacy of the licensee's system review to identify and include safety-related valves in the IST program, 2) if the selected valves were in the Units 1, 2, and 3 IST program, 3) if the valves in the IST program were tested in an appropriate manner for their safety-related functions, 4) if the selected test methodology demonstrated valve operability, 5) if test procedures correctly identified appropriate acceptance criteria, and 6) if the Code clarifications in Gl. 89-04 were properly addressed in a testing program.
The inspectors selected 40 check valves from the diesel generator fuel oil, emergency diesel generator, high pressure safety injection, low pressure safety injection, containment spray, essential cooling water, chemical volume and control, main steam, main feedwater and auxiliary feedwater systems. The inspectors selected pressure isolation check valves, pump discharge check valves, and containment isolation check valves.
The inspectors selected the emergency diesel generator and
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associated support systems to assess the degree to which safety-related skid mounted check valves were addressed in a testing program.
The inspectors reviewed test procedures to verify both open and closed operability of the AFW pump outlet check valves. The inspectors determined that the procedures provided for verification of quantitative acceptance criteria for both valve positions.
Except for the boron injection check valves, discussed in Section 2.4.1.3, the inspectors concluded that check valve testing was adequate.
2.4.6 Maintenance Proaram The inspectors reviewed aspects of the licensee's maintenance program for check valves to determine whether a program procedure existed to identify degradation before failure and whether appropriate corrective actions were taken to address problems based on the maintenance results.
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The inspectors reviewed six check valve maintenance work orders and did not identify any specific problems.
The inspectors noted that normal check valve maintenance work was performed per work orders which did not reference an engineering procedure, or receive an engineering review.
2.4.7 Trendina Proaram The licensee's trending program was included in procedure 73AC-0XIO3, Revision 01.02, " Preventive Maintenance of Check Valves." This procedure required that the results of the visual and non-intrusive inspections of check valves be maintained.
As noted in Section 2.4.1.3, the inspectors determined that the check valve engineer kept a ?og showing each cteck valve inspected, date of inspection, and whether the inspectior, was satisfactory or not. The check valve engineer also kept a complete file of the inspection results for valves inspected per procedure 73AC-0XIO3.
The inspectors noted that the licensee's work on check valves prior to 1990 was not in the file.
In addition, no active trending of dimensional or visual results were being perforraed. The inspectors reviewed the issue of trending with the licensee. The licensee stated that they were maintaining accurate and complete check valve inspection information, but had not yet decided the best method to assemble the information.
2.4.8 Corrective Action Proarant The inspectors reviewed the licensee's programs for identifying check valve operability and programmatic concerns, and the means utilized to evaluate the reportability of identified concerns.
This review identified the following:
2.4.8.1 AFW Pumo AFN-P01 Discharae Check Valve 3PAFN-V012 Inspection of non-essential AFW pump AFN-P01 discharge check valve 3PAFN-V012 corrective action files identified that a check valve examination was performed on April 11, 1991. Check valve examination report number 91-354, issued for this examination, identified that examination checklist item 4.f (hinge arm / bracket connection locking devices) and item 6 (additional exams) were -
rejected. This report identified that the internal hinge bracket cap screws did not have their locking device tabs bent up to lock the cap screws in place and that the existing external valve bonnet cap screws were not made from the design specified material.
Specifically, the report identified that four of the cap screws were unmarked (Grade 2) material and four of the cap screws were 304 material. A footnote on the examination report for these two items stated " change bolting to A193 B and bend up locking tabs."
The licensee's examination was performed per instructions in work order number 00444727 and procedure 73TI-9ZZ19, Revision 6 " Visual Enmination of Pump and Valve Internal Surfaces." Sectic,n 8.4.2 of procedure 73TI-9ZZl9 stated "An HNCR per 60AC-0QQ01 (an EER per 73AC-0EE01 for non-quality relate items) shall be initiated for all items reflecting an unacceptable condition."
The inspectors verified that Pacific Valves drawing number 7-509-B (Licensee drawing number P222B-141-4) identified auxiliary feedwater pump AFN-P01 discharge check valve 3PAFN-V012 bonnet cap screws, piece 2, material as ASTM A193, Grade 87.
Since an EER was not issued to evaluate the unacceptable conditions, the following actions required by licensee procedure 73AC-0EE01 were not accomplished:
Disposition instructions were not reviewed and approved by a
supervisor.
Measures were not established to assure the causes for these
unacceptable conditions were identified and corrective measures taken to preclude repetition. These unacceptable conditions may have been the results of inadequate valve reassembly instructions, material control, maintenance, personnel training, etc.
Evaluation of the impact on similar valves in other units was
not documented as being accomplished.
The licensee acknowledged the inspectors' concerns and identified that they would review the actions taken for the unacceptable conditions. The licensee issued CRDR 3-2-0525 to evaluate the nonconformance of the bonnet bolting.
The failure to issue an EER for the unacceptable conditions identified in report number 91-354 is a violation (50-530/92-36-03).
2.4.8.2 Steam Generator Feedwater Check Valve Inspection of steam generator feedwater check valve 1PSGE-V003 corrective action files identified a visual check valve examination was performed March 29, 1992.
Review of check valve examination report number 92-122, issued for this examination, identified that examination checklist item 1 (Freedom of Movement) had N/A entered with a note that stated "not moved due to size / weight." The check valve engineer identified that this note was entered because the disc assembly for this 24 inch diameter check valve weighed 500 to 700 pounds, and was too heavy to move to check for freedom of movement of the disc and examine all internal parts and surfaces.
Since the disc was not moved the disc seating areas and other valve internal parts and surfaces behind the disc were not examined.
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appeared that the disc was not moved in other similar 24 inch check valves, such as valves SGE-V005, SGE-V006, SGE-V007, etc., except when a valve was opened to investigate a potential problem.
During an inspection, initiated as a result of a suspected problem, the disc of 24 inch check valve 3PSGE-V005 was found hung between the open and closed positions. The licensee then moved the disc on this 24 inch check valve several times during the subsequent corrective maintenance.
One of the major reasons for disassembly and inspection of check valves is to verify that the disc moves freely with no evidence of binding that could cause a valve disc to stick or hang up in an unacceptable position.
Section 8.2.2 of Procedure 73TI-9ZZl9, Revision 6, " Visual Examination of Pump and Valve Internal Surfaces," states, in part, that, "for (check valve) examinations all internal parts and sucfaces shall be examined per Appendix B, as applicable."
Neither of the applicable licensee work instructions for valve IPSGE-V003, procedure 73TI-9ZZl9 and check valve examination report number 92-122, provided a documented evaluation of why it was acceptable to not verify the freedom of movement of the valve disc and to not examine the valve internal parts and surfaces behind the disc.
Failure to examine all internal parts and surfaces of check valve 1PSGE-V003 per Appendix B of procedure 73TI-9ZZ19 is a violation (50-528/92-36-04).
The licensee acknowledge the inspectors' concern and stated they would evaluate the need for additional procedure instructions.
The inspectors concluded that the check valve inspections were adequate when performed in accordance with the existing procedures.-
However, the inspectors also concluded that management oversight had not been adequate to insure that the procedures were followed.
2.4.9 Preventive Maintenance Implementation The inspectors identified as a program strength that ASME Section XI qualified ISI/ Nondestructive Examination engineers were performing visual inspections of check valves per procedure 73AC-0XIO3.
The licensee's preventive maintenance program is discussed in Section 2.4.1_of this report.
The inspectors observed the preventive maintenance inspection of Unit 3 check valve FTN-V020. This valve was a Pacific 14 inch swing check valve. The licensee had previously identified cignificant
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wear problems with this check valve installation in all three units.
The licensee inspected the valve and took disc and stem measurements and concluded that the valve was satisfactory without repair. The licensee provided the inspectors evidence that the bonnet of this check valve had previously been im)roperly assembled; the backseat indicated off-centered wear. The )onnet had been rotated from the proper position, causing misalignment between the swing arm and the backseat. The licensee had realigned the valve prior to this inspection and evaluated the off-centered wear as acceptable.
The inspectors concluded that the inspection of Unit 3 check valve FTN-V020 was adequate based on inspection of the check valve, observation of the licensee's activities and review of the completed records.
The inspectors also observed visual inspections, maintenance activities and internal valve surfaces for Unit 3 check valves FTN-V020, SG-V002, SG-V008, and SG-V432, which were being worked during this inspection. The inspectors did not identify any problems in these areas.
The inspectors concluded that the licensee had implemented an adequate visual check valve preventive maintenance program.
2.4.10 Use of Non-Intrusive Test Methods The inspectors reviewed the licensee's use of non-intrusive test methods.
The licensee was using acoustic equipment to monitor check valve performance during normal system flow conditions. The licensee mounted two or more acceleromoters on a check valve and recorded the response for computer aided analysis. The licensee stated that they were currently only using the acoustic equipment to find noises which indicated wear or backseat tapping. The licensee stated that they had not yet developed the capability to specifically define metallic noise sources and that they intended to open and inspect any check valve which exhibited any metallic noise.
The licensee had performed 23 non-intrusive check valve inspections.
Three check valves exhibited metal contact noises. These three check valves were opened and found to require corrective maintenance.
Normally, safety injection tank check valves were being opened and inspected each refueling to satisfy ASME Section XI testing, due to the inability to full flow test. These check valves were acoustically monitored during partial flow testing prior to their ASME Section XI disassembly.
The acoustic monitoring results matched the visual inspection results. The acoustic monitoring results were used to support an ASME Section XI relief request to
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discontinue routine disassembly of these check valves. The NRC approved the relief request.
The inspectors considered that the licensee was developing expertise in the non-intrusive acoustic monitoring of check valves. The inspectors concluded that non-intrusive monitoring was a program strength.
2.4.11 Trainina The inspectors reviewed outlines of routine and special periodic training provided to licensee personnel involved in the engineering review and maintenance of check valves.
The inspectors concluded that the training outlines were adequate.
2.5 [onclusions Based on the findings of this inspection, the inspectors concluded that the licensee was developing a comprehensive program for assuring check valve reliability.
The inspectors also concluded that additional management oversight was warranted in the areas of properly documenting inspection results, review of NRC and vendor information, and maintaining programmatic documents up-to-date.
Two violations of NRC requirements were identified.
3.
Desian Chanaes (37700)
3.1 Emeroency Diesel Generator load Calculation The inspectors reviewed the emergency diesel generator (EDG) load calculation 13-EC-DG-200, " Diesel Generator load Calculation." Approved plant changes, which had not yet been installed were included in the calculation as Calculation Change Notices (CCNs).
The inspectors noted that two CCNs bad been issued using data from superseded revisions of calculation 13-EC-DG-200.
Therefore, these two CCNs showed incorrect EDG loading.
The inspectors reviewed the licensee's process for issuing CCNs with the licensee.
The licensee stated the two CCNs with the incorrect EDG loading were issued because of personnel errors. The licensee issued a memorandum to staff to inform employees of the errors. The licensee issued a document control process change to prevent recurrence of the errors. The licensee verified that the latest calculated EDG loadings were correct and that the errors in the CCNs would not have overloaded the EDG.-
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The inspectors reviewed the licensee memorandum and process change and concluded that the licensee's actions were adequate to address the findings noted by the inspector.
No violations or deviations from NRC requirements were identified.
4.
Inservice Inspection - Observation of work and work activities (73753)
4.1 Work Activities The inspectors reviewed samples of Unit 3 inservice inspection (ISI) work activities in progress to ascertain that inspection, repair and replacement of components were being performed in accordance with applicable requirements. The review included the observation of ultrasonic examinations of main steam weld numbers 48-1, 48-2, 48-28, 48-29, 48-30, and 48-35.
Examination personnel observed during this review appeared to be knowledgeable and performed the examinations in an acceptable manner. The licensee was conducting the Unit 3 third refueling outage.
4.2 Oualification and Certification The inspectors reviewed the qualifications and certifications of the inspection personnel involved in ISI work activities in progress.
Personnel involved in the performance, evaluation, or supervision of nondestructive examination of safety related items met the American Society for Nondestructive Testing Recommended Practices No. SNT-TC-1A, 1980 Edition, " Personnel Qualification and Certification in Nondestructive Testing," and the ASME Section XI Code, 1980 Edition, Winter 1981 Addenda. No concerns were identified.
4.3 Reporti The inspectors reviewed approximately 450 completed ISI examination reports generated during the 3R3 outage to ascertain that the data was recorded, reviewed, and evaluated in accordance with previously established requirements and acceptance criteria identified in licensee procedure 73AC-0XIOl, Revision 1.03, "ASME Section XI Inservice Inspection." The inspector: _also reviewed the licensee's disposition of adverse findings in these reports to ascertain that the dispositions were-consistent with regulatory requirements.
There were approximately 460 ISI examinations scheduled to be performed during this outage.
A review of visual examination report number 92-3258 identified that--the-evaluation of mechanical snubber support 3SI-241-007 had been rejected.
A note _in the report stated " design load on snubber reads 6000 LBS, load on drawing reads 8308 LBS."
A footnote added by a licensee reviewer to I
the original examiner note stated in part that " condition verified j
acceptable per conversation with... APS snubber engineer."
l Section A-A of Revision 5 of licensee drawing 13SI-241-H-007 identified
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support 3SI-241-007 as a size 3, Class QlB, mechanical snubber with an i
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assigned load equal to 8308 pounds.
Class QlB is the licensee designation for safety related, seismic Class 1, ASME Class 2.
Section 8.5.2 of Revision 4 of licensee procedure 73T1-91Zl8, " Visual Examination of Support Components," states in part that "for all quality related items reflecting an unacceptable condition an HNCR [ Material Non-Conformance Report] per 60AC-00Q01 should be initiated, and for all non-quality related items an FER [ Engineering Evaluation Request) per 73AC-OEE01 should be initiated."
As of November 5, 1992, neither an MNCR nor an EER had been initiated following the licensee identification, on October 7,1992, of an unacceptable condition in the rejected evaluation of visual examination report number 92-3258.
The closecut of a rejected ISI examination report without a formal evaluation to properly document and evaluate identified non-conforming conditions is a violation (50-530/92-36-03). This is similar to the violation discussed in section 2.4.9.1 of this report.
The licensee acknowledged the inspectors' finding and issued EER 92-SN-017 to reevaluate visual examination report number 92-3258.
One violation of NRC requirements was identified.
5.
Previous 1v Identified _1tems (92701)
5.1 (Closed) Followuo item 50-528. 50-529. 50-530/89-28-08:
Preventive and Corrective Maintenance of Eauipment Important to Safety An inspector observed problems with non-safety related equipment which couldimpactspetyrelatedequipmentanddeterminedthatthelicensee neededtoex6indtheirprogramsforcorrectiveandpreventivemaintenance of non-safety related equipment.
Since that observation, the licensee expanded procedure 60AC-0QQ01, Revision 4.01, " Control of Nonconforming Items," to include corrective maintenance for non-safety related equipment which could impact safety related equipment.
The licensee was revising their routine preventive maintenance program using a modified reliability centered maintenance concept, which included non-safety related equipment.
In this inspection, the inspectors reviewed the licensee's MNCR program; the licensee's routine preventive maintenance program philosophy, as documented in procedure 30AC-9MP02, Revision 3, " Preventive Maintenance;"
and samples of preventive maintenance for non-safety related electrical equipment which could impact safety related equipment.
The inspectors determined that the licensee's program for corrective and preventive maintenance included non-safety related equipment and concluded that non-safety related electrical equipment preventive
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maintenance procedures were adequate to improve the reliability of this equipment to support safety equipment.
Based on a satisfactory review of the licensee's corrective and preventive maintenance programs for non-safety equipment and a satisfactory review of the adequacy of a sample of preventive maintenance procedures for this equipment, the inspectors concluded that this item was adequately resolved. This item is closed.
5.2 (Closed) Follq_w_yo Item 50-528. 50-529. 50-530/92-04-01: Weaknesses in the System Enaineerina Procram An NRC inspection noted weaknesses in the licensee's system engineering program. These weaknesses included issuance of certain design modifications without the responsible system engineer's knowledge, failure to properly route corrective actions through the responsible system engineer and failure of system engineers to perform required trending.
In response to these findings, the licensee took the following actions:
Revised design control documents to require the system engineer's
review of all design modifications.
Revised their corrective action program to require system engineer
review of associated corrective actions.
Revised their trending program to implement system engineer trending
of important safety system functions. The licensee initiated the new trending program on 10 pilot systems.
Re-organized the site engineering organization. The licensee stated
that one of the benefits of-the reorganization would be to maintain closer ties between system and component engineers.
The inspectors reviewed the licensee program changes and the licensee's new site engineering organization to verify the implementation of the l
program changes. As part of this review, the inspectors selected one of the 10 pilot systems, the Auxiliary Feedwater System (AFW), and reviewed the trended information. The licensee stated that they will expand the trending of the original 10 systems to include other safety systems.-
L The inspectors considered that the licensee program changes addressed and corrected the original weaknesses. The inspectors concluded that the AFW system report indicated adequate trending by the system engineer.
Based on the satisfactory program review, satisfactory AFW review, and i
the licensee's commitment to expand the trending to other systems, the l
inspectors concluded that this item was adequately resolved. This item
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is closed.
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5.3 (Closed) Followuo Item 50-528. 50-529. 50-530/90-42-07:
Rel ay Calibration Proaram The NRC Electrical Distribution System Functional Inspection (EDSFI) team identified that the licensee was not recording as-found relay data. The team noted that the licensee was calibrating type IFC relays every third refueling outage.
The manufacturer for the IFC relays recommended that these relays be calibration checked every one to two years, until operating experience was accumulated to select other calibration intervals. The team noted that without recording the as-found relay calibration data, the licensee had no method to accumulate operating experience.
In response to the team's findings, the licensee committed to record as-found relay data, to review the as-found data, and change relay calibration intervals to suit.
The inspectors reviewed samples of as-found relay data and noted that the licensee was calibrating a number of IFC relays every refueling outage, based on an independent review of each relay's safety importance.
The inspectors also noted that the licensee had increased the frequency of calibration for a number of non-IFC relays. The licensee stated that they had not completed the review of the as-found data taken to date.
Based on the licensee's action to increase relay calibration frequency and their commitment to review as-found data and modify calibration intervals as necessary, the inspectors concluded that this item was adequately resolved. This item is closed.
G.
Previously Identified Enforcement Items (92703)
6.1 (Closed) Deviation _ 50-528. 50-529. 50-530/92-14-01: Air Supply for
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Accomplishina Five Emeraency Diesel Generator Starts An NRC inspection noted that the licensee's Updated Final Safety Analysis Report (UFSAR) specified that sufficient air be stored to start an emergency diesel generator (EDG) five times without resupply. The licensee had no calculation to demonstrate this commitment. The licensee submitted test data to support the UFSAR commitment, but the test data was taken with stored air pressure higher than actual operating pressure.
The inspector concluded that the licensee had not demonstrated the UFSAR commitment.
The licensee reviewed the UFSAR commitment and their actual operating method. The licensee concluded that demonstrating the UFSAR commitment was not necessary since in the emergency start mode, air was supplied until the EDG starts. The licensee prepared a change to the UFSAR to match their operating method. The licensee performed a 50.59 safety evaluation of this UFSAR change.
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The inspectors reviewed the UFSAR change and the 50.59 evaluation. The inspectors concluded that the UFSAR now accurately reflected the actual testing performed and that the 50.59 evaluation was satisfactory.
Based on the UFSAR change and the satisfactory 50.59 evaluation, the inspectors concluded that the licensee's actions adequately resolved this item. This item is closed.
6.2 (Closed) Violation 50-528. 50-529. 50-530/90-42,02: Offsite Power does not Minimize the likelihood of Simultaneous Failure of Both Sources The Electrical Distribution System Functional Inspection revealed that when one of three startup transformers was out of service, the possibility existed to overload the remaining two startup transformers.
The overload could cause a loss of all offsite power to one or more of the units. Minor potential problems were also noted with plant loading calculations.
The licensee issued administrative control documents to ensure that startup transformer overload conditions would be prevented, submitted an UFSAR change to clarify that administrative controls were required when one of three startup transformers was out of service, and committed to vertfy plant loading calculations.
The inspectors reviewed the administrative-control documents and the UFSAR change. The inspectors found that the calculations were scheduled to be completed by December 1992. The licensee stated that no loading problems had been found which would affect the administrative control procedures. The inspectors reviewed the existing loading calculations.
The inspectors concluded that adherence to the administrative control document would preclude overload of the two remaining startup transformers when one startup transformer was out of service. The inspectors concluded that the UFSAR change accurately defined the existing offsite power arrangement. The inspectors concluded that changes to the loading calculations would not-have an affect on the-existing administrative control procedures.
Based on the administrative controls presently in place and the licensee's commitment to reverify load calculations, the inspectors considered this item adequately resolved. This item is closed.
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6.3 (Closed) Violation 50-528/91-21-01:
Breach in Fire Protection Barrier for Auxiliary Feedwater Pumo Train A Conduits An NRC '.pection discovered that a 10 CFR 50 Appendix R fire barrier protecting train "A" auxiliary feedwater (AFW) pump electrical conduit had been breached in the "B" train AFW pump room in-Unit 1.
The breach had been made in accordance with a work order, but that the fire impairment had not been identified in the plant's fire impairment log, as required by licensee procedure.
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-In response to these finding, the licensee entered the fire impairment in the log and repaired the breach.
The licensee determined that the problem was. caused by inccmplete planner review of the_ work and incomplete drawing information. Two separate licensee drawings existed which showed Appendix R requirements for the area of-the-breached-conduit'._ However, only one of the drawings _ identified that the. specific conduit was in the Appendix R program. The planner only reviewed the.
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drawing which did not show the Appendix R requirements for the subject-conduit.
The licensee corrected the associated drawings. The licensee reviewed other Appendix R drawings and found no other cases where more than one.
drawing showed Appendix R requirements for the same area.
The inspectors reviewed the licensee's actions, updated drawings and repair instructions. The inspectors found these items adequate.
Based on the inspectors' review of the fire impairment repair, and the licensee's review of additional drawings, the inspectors concluded.that the licensee's actions were adequate to resolve this item. -This item is
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closed.
6.4 (Closed) Violation 50-528. 50-529. 50-530/92-14-02:
Lack of Enoineerina Assessments for Safety and Important to Safety Eouioment Routinely Found Outside of Their As-found Acceptance Criteria The NRC Instrument and Control (I&C) Inspection team identified.that the licensee.had not been assessing equipment-operability for equipment-
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routinely found outside of.their as-found acceptance criteria. The equipment listed were the pressurizer narrow range pressure _ transmitters and the EDG low lube oil pressure trip transmitters.
In response to the findings, the licensee reviewed the_as-found. data and concluded that the transmitters were operable. The licensee review concluded that the as-found' acceptance criteria was the.same.as the as-left acceptance criteria, therefore the as-fo3nd acceptance criteria was conservative. The: licensee committed to ensure that as-found.
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acceptance _ criteria (that included allowances for-instrumentidrift) would be included in procedures, and that a proper review be-accomplished when-as-found data was outside the as-found acceptance criteria.E
The licensee issued -interim corrective action to document-'all-data which did-not meet-as-found acceptance criterion in-a Condition Report / Disposition Request-(CRDR). The licensee issued interim
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instructions to engineering personnel to review the CRORs with data'
outside as-found criteria.
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The licensee was performing calculations to determine-appropriate as-found acceptance criteria and was updating the procedures when-the
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The inspectors reviewed criteria established for the interim corrective actions, sample calculations which identified new as-found acceptance criteria, and samples of as-found data outside the acceptance criteria and determined that a CRDR had been issued and evaluated for each of 'the samples.
The inspectors concluded that the licensee actions on this item were adequate based on a satisfactory review of the licensee's interim program, a satisfactory review of calculations for new as-found acceptance criteria, and the licensee commitment to complete the calculations and update the procedures. This item is closed.
7.
Exit Meetina The inspectors met with the licensee management representatives denoted
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in Section 1, on November 6, 1992. The scope of the inspection and the inspectors' findings up to the time of the meeting were discussed.
The inspectors identified that additional information had been requested, and this information would be reviewed in the NRC Regional Office in order to complete the inspection. Review of the additional information was completed and the results are included in this report.
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Vmin and disc stability are seriously affected by independent parameter "Y" (2)
When Y/D <.25, actual Vm:., may be much higher than predicted by generalized Vmin equation, and disc stability may not be achievable with velocity increase Significance of Disc Projection (Y/D) on Performance APPENDIX A