IR 05000206/1986014
| ML13323B121 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 03/20/1986 |
| From: | Johnson P, Mendonca M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I), NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | |
| Shared Package | |
| ML13323B120 | List: |
| References | |
| 50-206-86-14-MM, NUDOCS 8604070204 | |
| Download: ML13323B121 (20) | |
Text
U. S. NUCLEAR REGULATORY COMMISSION
REGION V
Report N /86-14 Docket N License N DPR-13 Licensee:
Southern California Edison Company P. 0. Box 800, 2244 Walnut Grove-Avenue Rosemead, Californid 91770 Facility Name:
San Onofre Unit 1 Location:
Region V Office Walnut Creek, California Conference conducted:
March 12, 1986 Prepared by:
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c M. M. Mendonca, Senior Resident Inspector Date Signed Approved By:
P. hnson, Chief Date Signed React r Projects Section 3 Summary:
Management Meeting on March 12, 1986 (Report No. 86-14)
The licensee's plans and status for a May 1986 restart were discussed, in light of the concerns from a November 21, 1985 even O 0 6032
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MANAGEMENT MEETING Meeting Attendees Southern California Edison Company (SCE)
K. P. Baskin, Vice President, Nuclear Engineering Safety and Licensing M. A. Wharton, Deputy Station Manager M. 0. Medford, Manager, Nuclear Licensing J. L. Rainsberry, Supervisor, Licensing R. Ornelas, Licensing San Diego Gas and Electric R. L. Erickson, Senior Engineer Nuclear Regulatory Commission (NRC) Region V J. B. Martin, Regional Administrator D. F. Kirsch, Director, Division of Reactor Safety and Projects A. E. Chaffee, Chief, Reactor Projects Branch P. H. Johnson, Chief, Reactor Projects Section 3 F. R. Huey, Senior Resident Inspector, San Onofre P. P. Narbut, Project,Inspector M. M. Mendonca, Senior Resident Inspector, Diablo Canyon NRC Nuclear Reactor Regulation R. Dudley, Project Manager, San Onofre Unit 1 NRC Inspection and Enforcement R. P. Correia, Reactor Engineer, Vendor Branch Meeting Summary The meeting convened at approximately 10:00 a.m. in the Region V conference room. Mr. Martin made opening remarks and discussed the purpose of the meeting, i.e., to discuss the status of the licensee's root cause analyses and corrective action implementation in response to the November 21 loss of power and water hammer event at San Onofre Nuclear Generating Station (SONGS) Unit 1. Mr. Martin pointed out that the licensee's list of actions had been reviewed and appeared at that point to address the NRC staff concerns; however, the licensee should also assure themselves that the subject action list is well controlled, so that a quality product is forthcoming. Mr. Martin also emphasized the importance to the licensee's-evaluation.of the plant material condition to assure that plant equipment operates correctl Mr. Baskin then.stated that the licensee believed that SONGS Unit 1 would be ready-for restart in mid-May, and that 'this schedule would result i an acceptable evaluation and associated restart effort. Mr. Baskin also pointed out that the licensee-had given the NRC staff preliminary
evaluations and that final evaluations were forthcoming in the licensee's planned March 28 submittal to address remaining staff concern Mr. Chaffee pointed out that it was the staff's understanding that the licensee was about 2 weeks behind schedule due to problems in the refueling operations, and asked how that would impact the licensee's efforts. Mr. Baskin discussed some projected schedule delays in the seismic upgrade work, pointed out that the critical path as he understood was not affected, but agreed to check on the refueling operations delay Mr. Medford then presented the licensee's agenda for the meeting (Enclosure 1).
Following the agenda Mr. Medford summarized the licensee' 5position on the first topic, manual loading of diesel generator This position closely followed the points of the licensee's March 2 submittal. Mr. Martin asked if licensee procedures for loss of power addressed timing requirements for loading of diesel generators, and Mr. Medford indicated that they woul Mr. Medford then discussed the second topic on the licensee's agenda, root cause of check valve failure, which is to be completed for the licensee's planned March 28 submittal. Mr. Martin indicated the staff's concern that the analytical evaluations of the root cause contained significant uncertainties and that some form of confirmation of correct operation of the new check valves was perhaps appropriate, e.g., position indication. Mr. Wharton indicated that the licensee was considering three options for measurement of correct operations:
1) periodic inspection, 2) acoustic monitoring, and 3) energy spectrum analysi Mr. Baskin pointed out that the licensee is also planning to install
"backups" to the check valves that failed in the form of additional check valves inside conta'inment near the steam generators and automatic isolation of feedwater regulating valves on loss of feedwater pumps. M Ornelas then discussed replacement check valve design. Mr. Correia asked the extent of the input from the manufacturers on the replacement valves, and Mr. Martin suggested that-the licensee specifically ask the manufacturer "if the check valves should be used in the proposed application. The licensee is considering these suggestion Mr. Ornelas then discussed the new check valves inside containment following the licensee's agenda.The licensee is continuing the evaluations in this area. '-Although the new valves are expected to be full open at greater than 70% power, possible flow instabilities due to the check valve 'disc "dangling" in the.flow stream under auxiliary feedwater flow conditions and associated damage to the check valve seats are being considered by the licensee. These problems are considered possible due to sizing constraints for operation under both main and auxiliary feedwater flow conditions., Mr. Mendonca indicated that the potential addition of these new check valves inside containment and the other modifications to the feedwater system would change flow characteristics, such that the licensee may wish to consider preoperational testing (including feedring water hammer testing).
Mr. Wharton then presented the licensee's fourth agenda item on the impact of long outages on plant operations. He summarized the licensee's position as discussed in their March 2 submittal. Mr. Wharton discussed
the licensee's programs to assure equipment and personnel readines Mr. Kirsch asked what criteria were used to determine when to implement the long outage control program and Mr. Wharton indicated he would get back on that topic. Mr. Wharton discussed the licensee's area monitoring and material condition' standards programs. Mr. Chaffee indicated that the staff understood that the licensee had not fully implemented the area monitoring program, and Mr. Wharton indicated that the program was in a transitory state such that the last stage, site management evaluation, was not tried yet. Messrs. Kirsch and Chaffee reiterated the importance of the licensee's material condition and area monitoring programs to assure correct plant operations for restar Mr. Wharton then discussed cable failures and corrective actions to test and replace cable Mr. Medford then briefly presented the licensees proposed agenda for the Commission breifing on March 1 Finally, the staff indicated that a copy of current information requests would be transmitted with this report (Enclosure 2).
The meeting concluded at approximately 1:00 II
ENCLOSURE 1
SCE/NRC MEETING MARCH 12, 1986 WATER HAMMER EVENT SAN ONOFRE UNIT 1 AGENDA I. MANUAL LOADING OF DIESELS II. ROOT CAUSE OF CHECK VALVE FAILURE III. NEW CHECK VALVES INSIDE CONTAINMENT IV. IMPACT OF LONG OUTAGES ON PLANT OPERATION CABLE FAILURE EVALUATION V COMMISSION MEETING AGENDA
AGENDA FOR MARCH 18, 1986 COMMISSION MEETING ON LOSS OF POWER/WATER HAMMER EVENT SAN ONOFRE UNIT 1 I. PREFACE DAVID J. FOGARTY Il. INTRODUCTON KENNETH P. BASKIN III. DESIGN RELATED ISSUES MARK 0. MEDFORD FEEDWATER SYSTEM ELECTRICAL POWER SYSTEM C. OTHER DESIGN ISSUES IV. PROGRAM RELATED ISSUES RUSSELL W. KRIEGER MATERIAL CONDITION OF THE PLANT OPERATIONAL ISSUES V. CONCLUSIONS/CLOSING COMMENTS KENNETH P. BASKIN
ENCLOSURE 2
ch 13, 1986 Revision 10 I Actions to be Considered and Information to be Provided by SCE for SONGS Unit 1 Startup Due Status Item Description Date Completion Programmatic Actions The licensee's response to all the following requests for additional information shall include consideration of the IIT findings and the licensee's independent analysis of the November 21, 1985 even The licensee shall provide responses to these questions to the requesting office with copies to the RV, NRR, and IE lead The licensee shall also provide a list of Design Change Packages, revised Procedures, and documentation of other changes required from any of their November 21, 1985 event related evaluations to the SONGS Resident Inspector Office; and copies of selected documents from this list will be provided to.the SONGS Resident Inspector Offic Lead and Address Phone N Fax RV
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Al Chaffee (415) 943-3753 (415) 943-3804 or 5 USNRC 1450 Maria Lane, Suite 210 Walnut Creek, CA 94596 NRR
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George Lear, NRR (301) 492-7403 (301) 492-8110 USNRC Washington, D.C. 20555 IE
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Gary Zech, IE (301) 492-9663 (301) 492-7376 USNRC Washington, D.C. 20555 RV Requests for Additional Information Provide a program plan to outline SCE's program that was developed and implemented in response to the November 21 even (List I, Item 4) Provide a return to service report documenting the investigation conducted, the corrective actions to be implemented, the schedule for such corrective actions, and the overall conclusion (4) Include a description of the actions to assure that the low-levels in the steam generators did not result in damage or leave residual deleterious material ch 13, 1986 Revision 10 I Actions to be Considered and Information to be Provided by SCE for SONGS Unit 1 Startup Due Status Item Description Date Completidn Provide a description and evaluation of the SONGS 1 maintenance program for check valve Include:
a)
Trending of maintenance results and IST finding b)
Quality Assurance (QA) involvemen c)
QA involvement in Onsite Review Committee activitie d)
Management involvement and followup e)
Assignment of Responsibilities (1.g)
Provide a description and schedule for the corrective actions required from your evaluation of the SONGS 1 design related to the November 21 event. Coordinate with the Resident Inspector Office the need for additional informatio (3.b) Provide a description and schedule for the corrective actions required from your evaluation of the SONGS 1 feedwater system desig (3.d) For modifications on the feedwater system to preclude water hammers, provide a description of any testing to provide additional assurance that water hammers will not occur in the feedring or the rest of the syste.
Provide a description and evaluation of the process for SONGS-1 abnormal conditions evaluation and post-trip review Also, include a description of responsibilities and independence of:
Offsite Review Committee Onsite Review Committee Quality Assurance Organization Plant Enginerring Review (4.b.1) Evaluate process for abnormal conditions evaluations and post-trip reviews, including recent experience with feedwater line B noise evaluation by Onsite Review Committee. Provide a list of improvements identified from this evaluatio (4.b.2)
ch 13, 1986 Revision 10 IV. Actions to be Considered and Information to be Provided by SCE for SONGS Unit I Startup Due Status Item Description Date Completidn Provide a description and evaluation of the administrative control program for maintenance record Include:
A description of methods to assure completeness, accuracy and retrievability, e.g.:
Management and Supervision Review and Followup Quality Assurance Interfaces Quality Control Interfaces Responsibilities Assigned (5.a.1) Provide a description and ev41uation of the tracking and trending of maintenance record Include: The use of maintenance documentation (both corrective and preventive activities and procurement requests) in equipment history documentatio Equipment history review process to establish trend Feedback into the maintenance program and plant configuration of finding Procedures for the processes with assigned responsibilitie QA overview of maintenance record Specifically, address the cancellation of Maintenance Work Orders on check valves that failed (as discussed in the IIT section 6.5) and provide justification for their cancellatio (5.b)
1 Provide an evaluation and any identified corrective actions for the following procedural problems identified from the November 21, 1985 event: Precaution on length of time diesel generators can operate unloaded without AC power to radiator fans was improperly deleted from procedur (IIT 17.2.1.5, Pg. 7-6) Lack of provisions for recognizing and preventing conditions which allow the ioi4iaon of water 4qiyp (IIT q6.1, "- (-2, 3 and 4)
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h 13, 1986 Revision 10 IV. Actions to be Considered and Information to be Provided by SCE for SONGS Unit 1 Startup Due Status Item Description Date Completion Inadequate instructions for manually bringing power onto dead buses and for responding to malfunction of the loss of ac power automatic sequence (IIT 3.4, Pg. 3-6; 57.2.1.4, Pg. 7-5);
4.12.2.1, Pg. 4-11) Inadequate instructions for trouble shooting of 4KV bus ground Include an assessment of appropriateness of parrelleling buses with indicated ground faul (IIT 58.1, Pge. 8-1);
14.12.3, Pge. 4-11; 3.2, Pg. 3-2; 14.13, Pg. 4-15; 14.14, Pg. 4-16; 7.2.1.5, Pg. 7-6) Lack of provisions for identifying alternate methods of verifying SI actuatio (IIT 17.2.1.3, Pg. 7-4) Need for revision to AFW system flow control procedures to factor in effect on reactor coolant system temperatur (IIT 6.1, Pg. 6-3) Procedure for going onto RHR cooling implied clearing of isolation valve interlock at 400 vice 370 psi (IIT 58.8,,Pg. 8-3; 7.2.1.8, Pg. 7-7; 3.8, Pgs. 3-12&13; 14.10, Pg.4-8; 17.2.1.8, Pg. 7-7)
1 In light of the above evaluations of item 10, provide a description of the program changes required to assure acceptable procedural developmen Include consideration of: Management and supervision review and followup; Peer Review Dry Run-Throughs of New or Revised Procedures Quality Assurance/Quality Control involvement Compliance involvement Tracking of commitments and requirements that are fulfilled by procedures, and assurance that procedure revisions do not obviate the compliance to any commitment or requiremen (6.a & b)
h 13, 1986 Revision 10 IV. Actions to be Considered and Information to be Provided by SCE for SONGS Unit 1 Startup Due Status Item Description Date Completioh 1 Provide an evaluation and any identified potential corrective actions on the following operator training concerns that arose from the November 21, 1985 event: Troubleshooting and isolating grounds including bus and transformer ground (IIT V7.2.1.1, Pgs. 7-1 thru 4) Transfer of loads between 4KV buse (IIT 7.2.1.1, Pg. 7-1) Operator response to loss of offsite electrical powe (IIT 17.2.1.2, Pg. 7-4) Resetting Unit Tri (IIT 7.2.1.4, Pg. 7-5) Controlling SG Blowdow (IIT 53.7, Pgs. 3-10&11) SLSS sequencer panel indication (IIT 14.13, Pg. 4-16) Not notifying NRC that a UE had been declare (IIT 7.2.2.2, Pg. 7-9),
and T7.3.2, Pg. 7-15) (Response should be included to item 14 of this list) Prompt implementation of technical specification action statements when warranted, i.e., reluctance to fully isolate failed tranforme (IIT 3.2, Pg. 3-2)
Also, evaluate if operators considered the Technical Specification shutdown and Notification of Unusual Event requirements of removal from service of one feedwater pump as limitin (7.a)
13. Based on the above evaluations of item 2, provide a description of any changes to the operator training program that are deemed appropriate. Include consideration of: Training Material including component engineering and actual operational informatio Training Time (Classroom and Simulator). Instructor Effectivenes Emphasis on Technical Specifications and relationship to safe plant operation Fee4back of changes in procedures, plant confV -ration, and industry experienc h 13, 1986 Revision 10 I Actions to be Considered and Information to be Provided by SCE for SONGS Unit 1 Startup Due Status Item Description Date Completion 1 Describe the basis for the initial notification to the NRC at 07:51 EST (e.g., implementation of emergency plan, 10 CFR 50.72 one hour report, etc.). If the initial notification was 10 CFR 50.72, was the emergency plan implemented?
If so, when was the event classified and declared? Describe the offsite notifications mode and identify related procedures implemented, including the initial notification to the NRC Operations Center that an event had been declare (8.a)
1 Describe the effort to identify whether the spurious ringing of the Emergency Notification System (ENS) which, apparently coincident with power system transients, is the result of responsibilities belonging to Southern California Edison Compan Describe any findings or actions taken in response to Information Notice No. 85-7 (8.b)
1 Describe the onsite notifications, including any to the STA, made in connection with the November 21 event and identify related procedures implemente (8.c)
1 Provide an evaluation of the affect of long outages on plant components as related to SONGS- (10)
1 Provide a description of your integrated program for review and upgrading overall plant material condition ("Material Condition Standards Program" MCSP).
Include: Use of maintenance records including trending and feedback into the progra Include:
~Preventive and Corrective Maintenance Activities
Procurement Records
Equipment Histories
h 13, 1986 Revision 10 IV. Actions to be Considered and Informat to be Provided by SCE for SONGS Unit 1 Startup Due Status Item Description Date Completidn Use of test results including trending and feedback into the progra Industry Experience Equipment layup and maintenance for long outage Engineering evaluations Criteria and responsibilities for determination of maintenance frequency and for priorities on plant improvement Required changes to the operations, maintenance and engineering programs (Area Monitoring Program) to implement MCS (11)
1 Provide a determination and supporting documentation of the adequacy of the various check valve designs for application in the feedwater and other safety-related system This determination should include, as appropriate: Evaluation of check valves that do not have integral internals to:
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Assess existing inspection or test result Assess existing maintenance historie Perform and evaluate the results of disassembly and visual inspection of selected check valves based on the results of the above review For check valves with integral internals:
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Determine which valves are only partially open during nominal operating condition Assess existing inspection and test result Review existing maintenance historie Perform and evaluate the results of disassembly and visual inspection of selected check valves based up on rer'>s of the above review ch 13, 1986 Revision 10 IV. Actions to be Considered and Information to be Provided by SCE for SONGS Unit 1 Startup Due Status Item Description Date Completion Request for Additional Information - NRR Items (50.54f) Describe steam generator blowdown isolation features and provide an evaluation of the steam generator blowdown system, including the following: Any proposed features which preclude automatic reinitiation of steam generator blowdown upon reset of the steam generator blowdown isolation signal or appropriate justification for not doing s Features which allow monitoring status of the steam generator blowdown system including the need for flow monitoring capability or valve position statu Specifically address control room status indicatio (3.a.3) Describe the current (as modified prior to restart) SONGS-1 main steam and feedwater system design and the basis for the design. Additionally, you should address the following: Specific water hammer design considerations and any instrumentation to indicate impending water hammer conditions. Include in your discussion the basis for concluding that the water hammer originally occurred in the feedwater line and not the feedring. Also compare your design considerations for water hammer with vendor recommendations to prevent water hamme Measures taken or to be taken to verify the integrity of feedwater piping and supporting structures (including concrete) prior to return to service. Also, provide a summary of the results of NDE of pipe weldments and any metallographic examination of feedwater pipe crack Results of any reevaluation of existing design of main steam and feedwater systems with respect to potential for loss of heat sink in the event of steam or feedwater system rupture. Include in your discussion, as appropriate, consideration of manual and automatic actuation of steam line isolation valves and assurance of steam generator availability to remove decay hea (3, 3.a.2, and 3.c)
h 13, 1986 Revision 10 I Actions to be Considered and Information to be Provided by SCE for SONGS Unit 1 Startup Due Status Item Description Date Completioln Provide an evaluation and description of your consideration to provide an uninterruptible power source (UPS) for the Critical Function Monitoring System (CFMS)
in order to enhance the plant post-trip review capability. Describe administrative procedures for resetting the CFMS after troubleshootin (4.c) Provide a discussion of the neutral grounding of auxiliary transformer "A".
Is the neutral grounded through an impedance?
If so, what is the value of neutral impedance and of the ground fault curren (6.c) Provide a description of the relay protection and settings for the auxiliary transformer "A" grounded neutra (6.c) Provide an evaluation of the rationale for not loading diesels automatically when power to Class 1E buses is lost from the offsite sourc (3.a.1) Provide information on Safeguard Load Sequencing System (SLSS) including logic, type, and description of operating mode (3.a.4) Provide information on load sequencing of load groups for loss of station power with discussion of status lamps in the surveillance panel (3.a.5) Provide information on station loss of voltage auto-transfer scheme. Discuss how the automatic transfer of electrical power recovery is accomplishe (3.a.5)
1 Provide information on any fault locating and/or maintenance testing procedures of 4.16 Kv cable circuits at San Onofre nuclear generating plan (7.a.1)
1 Provide a description of the power supply to vital 120V Bus # Is the supply to vital 120 volt Bus #4 from 7.5 KVA transformer or unregulated 37.5 KVA transformer?
Are the transfer switches associated with the supply to vital 120 volt Bus #4 and the 7.5 KVA and 37.5 KVA transformer manual or automatic?
(No category)
1 What was the phase-relationship between transformer A and transformer C windings when both transformers were momentarily parallele (No category)
1 For loss of Bus #4, provide an evaluation of the necessity to scram the reactor?
(No category)
ch 13, 1986 Revision 10 I Actions to be Considered and Information to be Provided by SCE for SONGS Unit 1 Startup Due Status Item Description Date Completion 1 Provide the rationale for not restoring Bus 2C from Bus 1B before manual scramming of the reactor?
(No category)
1 Discuss any design changes to eliminate spurious SI indicatio (3.a.4)
1 Discuss interlocks, including basis for interlocks, associated with the diesel generator output breaker; and provide an evaluation of the appropriateness of these interlock (3.a.6)
1 Discuss the basis for maximum permissible time limits on loading of diesel generators following loss of station powe (3.a.1)
1 Describe provisions made for reconstructing event data following loss of station powe (4.a)
1 Describe any improvements to be made for labeling of selected control room indicator (3.a.7)
2 Provide an evaluation of the need of an uninterruptible power such as inverter power to vital Bus #4. (3.a.8) IE Questions for SCE (50.54f) Provide a report and supporting documentation which addresses the root cause of the November 1985 water hammer event and SCE's proposed corrective action Include discussion of the root cause of the check valve failure (1.a) Provide a determination and supporting documentation of the adequacy of testing programs and procedures, as implemented, to detect degraded and failed safety-related check valve Describe any QA involvement in the testing program.
Provide a determination and supporting documentation of the adequacy of the design and related testing, maintenance, and inspection programs for the various check valves in the feedwater and other safety-related system.
Describe any additional sensors, such as acoustic monitors, that will be used to account for uncertainties in the effect of turbulence on feedwater-stem check valve disc (1.f)
ch 13, 1986 Revision 10 I Actions to be Considered and Information to be Provided by SCE for SONGS Unit 1 Startup Due Status Item Description Date Completion System Design/Operating Data At steady state 92% rated thermal power (RTP), what are the feed flows l
(in lb/hr and gpm), pressures, and temperatures encountered at the feed pump discharge check valves (12") and the steam generator feed line check l
valves (10")?
How was this data obtained? What were the above data at steady state 100% RTP?
How was the data obtained? What is the minimum steady state flow rate, along with pressures and l
temperatures, that these valves encounter? Valve Technical and Performance Requirements What was the design basis for the 10" and 12" valves in terms of flows, l
port size, obturator weights, pressure, and temperatures for both the the MCC-Pacific and Atwood-Morrill valves? How does this differe from l
actual values? What are the acceptable operating ranges for the new valves and what is the impact on plant/system operations? What are the maintenance, installation, and operation requirements or quidelines provided by MCC-Pacific and Atwood-Morrill? Will the new valves be modified to include operator assists or position indicators? What are the "enhanced" surveillance and maintenance requirements and their basis for the.Atwood-Morrill valves? Are they from or concurred l
by the manufacturer? What are.the bonnet and packing torque valves? Where is the actual hinge and disc combination center or gravity?
ch 13, 1986 Revision 10 IV. Actions to be Considered and Information to be Provided by SCE for SONGS Unit 1 Startup Due Status'
Item Description Date Completioh Vibratory Loads Clarify the method of development of the factor that turbulence loads I
from upstream components will not exceed 10% of disc weight? The ISA Handbook of Control Valves provides recommendations on installatio l Why or why can't these locational restrictions be correlated to check valves?
l Atwood-Morrill recommends not locating check valves within specific distances of turbulence producing components. What is the basis for deviating from these recommendations? Clearly indicate the source and reliability of the Atwood-Morrill valve data used in the redesign calculation.
Procurement What was the procurement history for the original valves and spare parts?
l Were other types of valve designs considered for this application (e.g., tilting l
or damped disk)? What is the basis for choosing a swing check design?
1 What flow band can result in a valve disk flutter problem for each of the new l
valves?
1 Include a discussion on how the auxiliary feedwater operating flow band avoids I
disc flutter or vibration of other check valves in the main feed and auxiliary l
feedwater piping system.
Clarify the statement made in handouts used at the January 31, 1986 meeting I
with the NRC that an error existed in Crane Technical Paper 410 that may have l
contributed to this problem.