IR 05000312/1987001
| ML20211H624 | |
| Person / Time | |
|---|---|
| Site: | Rancho Seco |
| Issue date: | 02/06/1987 |
| From: | Andrew Hon, Jim Melfi, Myers C, Richards S, Suh G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | |
| Shared Package | |
| ML20211H494 | List: |
| References | |
| TASK-2.E.4.1, TASK-TM 50-312-87-01, 50-312-87-1, GL-83-28, GL-85-10, IEB-79-14, NUDOCS 8702260224 | |
| Download: ML20211H624 (11) | |
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U. S. NUCLEAR REGULATORY COMMISSION
REGION V
Report No:
50-312/87-01 Docket No.
50-312
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License No. DPR-54 Licensee:
Sacramento Mu.,icipal Utility District P. O. Box 15830 Sacramento, California 95813 Facility Name:
Rancho Seco Unit 1 Inspection at:
Herald, California (Rancho Seco Site)
Inspection Conducted: January 5-9, 1987 and February 6, 1987 Inspectors:
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2M/gp J. F./#elfi, Reactor Inspector Date Signed 8A 2YD
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A. H W Reactor Inspecto Date Signed WA 4/f/s7 G. Y.#5uh, Reactor Inspe tor Date Signed
, -^ $A WS SI C. MyWs, Resident Inspector Date Signed
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.2h {n7 S. A. Richards, Chief, Engineering Section Date Signed Summary:
Inspection conducted January 5-9, 1987,'and February 6, 1987
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(Report 50-312/87-01)
Areas Inspected:. This routine inspection by Regional Inspectors involved the areas of part 21 reports, LERs, Generic Letters, Outstanding, Enforcement, and Followup items.
During this inspection, Inspection Procedures 30703, 92700, 92701, 92702, and 92703 were used.
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Results:
Of the areas inspected, no additional violations were identified.
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Three violations previously identified in Inspection Report 50-312/86-07 are
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issued with this report.
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DETAILS 1.
Persons Contacted a.
Licensee Personnel
- K. Perkins, Restart Implementation Engineer
- S. Knight, Quality Assurance Manager
- R. Colombo, Regulatory Compliance Superintendent
- S. Farkas, Compliance Engineering Associate
- J. Robertson, Lead Coordinator, Licensing
- T. Shewski, Quality Engineer
- F. Hauck, Senior Engineering Technician, Regulatory Compliance
- H. Wilkerson, MOV Project Manager P. Anderson, Electrical Engineer N. Thibodaux, Surveillance Engineer D. McGrath, M0 VATS Production Supervisor G. Clefton, Assistant Nuclear Maintenance Manager M. Anderson, Program Director, M0V Program M. Caldwell, Records Management and Information Supervisor S. Dutschke, Records Management Specialist J. Irwin, Senior I&C Engineer R. Daniels, Electrical Engineering Supervisor B. White, Senior Electrical Engineer Other licensee employees contacted included technicians, operators, mechanics and office personnel.
- Attended the Exit Meeting on January 9, 1987.
2.
Part 21 Reports (Closed) 85-15-P, "TEC Model 914-1 Valve Flow Monitor Module" In a 10 CFR 21 report, Technology for Energy Corporation identified a deficiency in its TEC Model 914-1 Valve Flow Monitor Modules which resulted in a failure of the module to reset after indicating full flow through the valve being monitored.
The vendor reported that 39 TEC Model 914-1 modules were supplied to SMUD for use at Rancho Seco.
The vendor stated that the deviation was a " birth defect," i.e., a failure present at manufacture or early in operatic ral life.
The vendor provided a test procedure to its customers to deteraine if their modules contained this defect.
The TEC 914-1 module at Rancho Seco is used to monitor valve flow for the pressurizer ralief and safety valves, the main steam line code safety valves, and the atmospheric dump valves.
The inspector reviewed the records of the tests performed by the licensee in accordance with the vendor's procedure.
All modules except one spare unit, which was subsequently removed from service permanently, reset properly.
The tests were completed within one month of receipt of the vendor's letter. The unit was in a shutdown during this time period.
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Based on the above, the inspector determined that the licensee responded in a timely manner,~and that the response appeared to be adequate.
This item is closed.
(0 pen) 86-18-P, Cracking of Limitorque Limit Switch Rotors This Part 21 report concerns the cracking of the white (melamine) limit switch rotors on Limitorque actuators on Class 1E valves.
In the report issued by the licensee, 2 rotors were found to have cracks out of an initial sample of ten valves inspected.
The licensee is inspecting all of the rotors on class 1E valves and replacing those found cracked.
The cause of the crack (s) appears to be overstressing of the rotor where the pins connect it to the gear box of the rotor due to oversized pins.
The cracking of limit switch rotors has also been reported by several other utilities and Limitorque.
NRC Information Notice 86-71 describes this problem.
The replacement of rotors that the licensee finds cracked is consistent with the vendor recommendations.
During the inspection, the inspector was told that a significant number of rotors were replaced.
The licensee is conducting an investigation to determine the reasons why the rotors required replacement.
This Part 21 report will remain open pending the conclusion of the licensee's investigation.
3.
Generic Letters (Closed) GL-85-10, " Technical Specification Changes as a result of Generic Letter 83-28."
This Generic Letter (GL) was written to address items 4.3 and 4.4 of the Salem Anticipated Transient Without Scram (ATWS) event (GL-83-28).
Item 4.3 of GL-83-28 requires licensees to submit Technical Specification changes for a modified design to the reactor trip mechanism.
Item 4.4 of GL-83-28 requires the incorporation of an appropriate surveillance into the Technical Specifications to address testing of the Silicon Controlled Rectifiers (SCRs).
The licensee submitted proposed Technical Specification (TS) amendment 114 on October 19, 1984 The generic letter was issued May 23, 1985.
The licensee then submitted revision 1 of the TS amendment on November 8, 1985, which superseded the criginal. The licensee added supplement 1 to revision 1 on December 9, 1986, which was an inclusion of pre-startup test requirements.
Item 4.4 of the proposed amendment was determined to be acceptable by the
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NRC in a letter dated November 4, 1986 (Stoltz to Ward).
Item 4.3 is still pending NRC staff review of the supplement.
The surveillance on the SCRs is performed by Surveillance Procedure I.108.
Based on the licensees' actions, this item is closed.
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4.
Licensee Event-Reports (LERs)
(Closed) LER 85-11, Revision 1, "RPS Channel Trip During Heatup when the Shutdown High Pressure Setpoint was exceeded" Revision 0 of this LER was closed out in inspection report 50-312/86-36.
Revision 1 to the LER was reviewed by the inspector to note any changes to the LER.
The only substantive changes were that the time of occurrence was changed and the information describing the event was made more specific.
Based on the previous closure, and the minimal changes made to the revision, this LER is closed.
(0 pen) LER 86-10, " Redundant Cabling in the Same Fire Area" The inspector continued to review the licensee's effort in resolving this LER and addressing the potential generic problem with the Cable Raceway Tracking System (CRTS).
The licensee informed the inspector that the original cable tracking system used by Bechtel during construction was Bechtel System EE553.
After plant operation in 1974, the same system was used for plant modifications.
The licensee initiated the conversion from Bechtel's EE553 to an in-house CRTS in 1979.
Upon completion of the convdrsion in 1981, a self checking program was run on the CRTS and identified a number of discrepancies in meeting the CRTS built-in criteria.
The licensee determined then these discrepancies were mostly due to software incompatibilities and no safety significance was attributed.
Currently, the licensee is performing calculations to disposition these discrepancies as well as others found to date.
The inspector reviewed samples of the calculations and found them to be adequate.
While_ reviewing these discrepancies, the inspector identified several instances where the commitments of FSAR Section 8.2.1.11, " Evaluation of physical layout of electrical distribution system equipment," such as cable tray overfill limits and intermixing of power and instrumentation cables, were apparently not met.
The licensee committed to provide the inspector with the appropriate justifications and evaluations performed prior to deviating from the FSAR commitments (10 CFR 50.59 reviews).
The inspector will follow this and other actions related to the resolution of CRTS during future inspections.
This item remains open.
5.
Followup Items (Closed) 84-19-08, Examination of Hardware for TMI Item II.E.4.1, H
Penetrations This followup item was for the inspection of the hardware installation for TMI item II.E.4.1, H, Penetrations.
This item is to provide a dedicated penetration for postaccident combustible gas control of the containment atmosphere.
The hardware for this TMI item was inspected and the item closed in Inspection Report 50-312/85-09.
The report was reviewed and based on the inspection report, this item is close.
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-(Closed) 85-13-01, Leak Rate Work on Valves The reactor coolant drain header penetration, No. 73, failed its Local.,
Leak Rate Test (LLRT) by surveillance' procedure (SP) SP 205.02. The leak rate'was determined to be approximately 250,000 sccm (standard cubic
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centimeters per minute).
Technical Specification 4.4.1.2.3 requires that the total rate of leakage from the reactor building shall not exceed 0.06 percent in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
This equates to approximately 106,000 sccm.
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licensee determined that valve SFV-60003 had excessive seat leakage.
The licensee stated that debris under the valve seat apparently caused the excessive seat leakage.
The licensee cleaned the valve and the penetration passed the LLRT.
A review of past LLRT results for this penetration did not indicate a trend of LLRT failures.
The inspector also determined that the licensee is monitoring the LLRT results on all penetrations for adverse trends.
This item is closed.
(Closed) 85-17-01, " Procedure Discrepancy for Maintenance Inspection Data Reports" This followup item resulted from the identification of an apparent discrepancy between Quality Assurance Procedure (QAP) 13, Revision 0, which calls for Maintenance Inspection Data Reports (MIDR) to be routed to Quality Assurance for approval, and a flow chart in Administrative Procedure (AP) 3 which did not indicate this step for processing a MIDR.
The inspector reviewed the licensee's followup action to this item.
Revision 31 to AP 3, which explicitly shows in a revised flow chart that MIDRs are to be processed through Quality Assurance, was approved on June 28, 1985.
The inspector reviewed several MIDRs processed during the time period before and after Revision 31 to AP 3 and found that Quality Assurance approved each MIDR.
Based on this review, this item is closed.
It should be noted that QAP 13 has now been replaced by QAP 6, titled
" Inspection Planning,",and that AP 3 is in its 36th revision.
In these procedures, MIDRs have'been replaced by Work Request Continuation Forms.
The inspector reviewed QAP 6 and AP'3, Revision 36 (Draft), and verified that these procedures call for Quality Department approval of a work package during the planning stage and a final review by Quality Assurance
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of the Work Request package to assure that the designated inspection activity has been completed.
(0 pen) 85-22-01 through 85-22-13, " Appendix R Exemption Requests,"
85-22-07 (Closed)
In a previous inspection, twelve Appendix R fire protection exemption requests pursuant to 10.CFR 50.12 were identified as open items pending formal review of the exemption requests by the NRC Office of Nuclear Reactor Regulation.
The licensee also committed to and subsequently requested (in a November 7, 1985 letter) an additional exemption concerning the lack of a fire suppression system in the control room.
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Open item 85-22-07 deals with an exemption request from Subsection III.L of Appendix R to 10 CFR 50 to the extent that it requires the capability to achieve cold shutdown in 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
In a May 19, 1986 letter, the NRC granted the requested exemption and, thus, item 85-22-07 is closed. With regard to the other twelve outstanding exemption requests, NRR has not completed its review of the requests to date; and, thus, Followup Items-85-22-01 through 85-22-13, with the exception of 85-22-07, will remain open.
(Closed) 85-25-01 " Loose Lock Nuts on Pipe Hangers" During IE Bulletin 79-14 walkdowns in 1985, the licensee identified several hangers on the main steam lines which had loose lock nuts.
These hangers were not part of the original 79-14 walkdown.
The licensee requested Bechtel to review the design of these hangers and determine whether they should have been inspected under the original 79-14 walkdown.
Bechtel Engineering performed an analysis of the "as found" pipe hangers and loose lock nuts, and found them capable of performing their safety function.
Further, they determined the hangers to be outside the scope of the 79-14 walkdowns.
Based on the licensee's action and the inspector's review of the report, this item is closed.
(Closed) 86-21-01 " Diesel Generator Panel Troubleshooting" While performing a battery test on battery BA, the system was aligned to its normal configuration and was awaiting its post test recharge.
The standby battery charger can support either the A or B bus.
Attempts were made to align the normal battery charger in parallel with the standby battery charger.
It tripped several times and the process was discontinued.
It was then noticed that 3 panel annunciator lights were burned out on both the 'A" and 'B' Diesel Generator (DG) panels (6 total).
The burned out indicator lights were as follows:
Lamp No.
Name Fed from Breaker
'A' Diesel Panel H7J272
DC Air Compressor Stopped 72-A09 (DC)
AC Air Compressor Stopped 52-2A115 (AC)
Fuel Oil Transfer #2 Stopped 52-2A114 (AC)
'B' Diesel Panel H7J273
DC Air Compressor Stopped 72-B09 (DC)
AC Air Compressor Stopped 52-2B116 (AC)
Fuel Pump Shutdown 52-804 (DC)
The licensee declared both DGs inoperable due to the unexplained light failures.
The normal surveillance tests on the DGs were then performed, the DGs passed the test and were declared operable.
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The licensee investigated the incident to determine if there was a connection between the two trains, or if other testing possibly caused the burnouts of the lights.
To burn out the lights on both the A and B trains from this event, the transient that occurred on the
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DC bus must have also affected the 'B' DC bus and the 'A'
and 'B' 480VAC motor control centers.
The only indirect physical link between the DGs was at the battery chargers.
The A battery chargers are fed from A 480V MCC S2A1.
The 'A' standby battery charger is fed from 'B' 480 MCC 52Bl.
The normal and standby battery chargers are designed to operate in parallel when necessary.
While in this mode of operation, there is an indirect physical link between the trains.
However, this link is indirect due to isolation provided by rectifiers, transformers, and filter circuits.
No other links were identified by the licensee.
After the tests the light bulbs were replaced and lit back up.
The lights are normally checked shiftly, and any burned out lights are promptly replaced. The replacement of burned out lights is not recorded.
The licensee issLed Special Test Procedure (STP-960), " Diesel Generator Electrical Cabinet Troubleshooting," to recreate the event on the "A" bus while monitoring both diesel generator engine cabinets.
The licensee ran the special test to try to duplicate the same event.
The licensee did not notice any change in the voltages to the lights.
The licensee believes that the lights burned out randomly.
In addition, to further justify this conclusion, the licensee stated that if the transient had affected both circuits to burn out the lights, the fuses would have been blown and more lights on the control panels would have been burned out.
In reviewing the test results, the inspector noted there were no voltage surges that could have caused the burned out lights.
The inspector concluded that the licensee's action to determine the root cause of the problem appeared adequate.
Based on the inspector's review, this item is closed.
(Closed) 86-22-01 " Distribution of Temporary Changes to Procedures not made to all Controlled Copy Holders" In report 50-312/86-22, the inspector noted that the licensee allowed temporary changes to procedures during calibration, providing that the change was concurred by the shift supervisor and approved by the Plant Review Committee in 7 days.
The changes would then be incorporated into later revisions to the procedure, as necessary.
Before the temporary change became a permanent revision, it was attached to the controlled copies of the procedures in the control room and the central procedure file only.
Other controlled copies of the procedure in the plant would not have the temporary revision (s) to the procedure that had been issued.
To address this potential problem, the licensees' Administrative Procedure (AP) 2.04, " Temporary Change to Procedures", now states that the procedure clerk will make distribution of the final approved temporary change to all the controlled copy holders on the sit.
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Based on the licensee's action, this~ item is closed.
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Enforcement Items Inspection Report 86-07 Violations Inspection Report 50-312/86-07 detailed the Region V inspection of the December 26, 1985 Rancho Seco overcooling event.
As a result of the inspection, several violations and a deviation were identified in Paragraph 2 of the report, and were issued as part of an escalated enforcement action on October 22, 1986.
The other violations identified in Paragraph 3 of Inspection Report 50-312/86-07, which were not related to the escalated enforcement action, are being issued with this report and are summarized as follows:
Failure to have certain required emergency procedures (See Appendix A).
This will be tracked under Enforcement Item 50-312/87-01-01.
It was concluded that the other procedures noted to be deficient in Item 0-7 of the report (loss of 125 VAC, tornado, and irradiated fuel damage) were minimally acceptable.
Violation of Technical Specification operability limits for the emergency filter system.
This violation will continue to be tracked under the existing Followup Item 50-312/86-07-05.
Failure to have procedures specifically addressing crimping tool calibration and control.
This violation will continue to be tracked as Followup Item 50-312/86-07-11.
At the time of the inspection, the licensee identified Item 86-07-11 as a followup item.
The licensee has taken steps to strengthen Administrative Procedure AP.33, " Calibration and Control of Measurement and Test Equipment (M&TE)." The crimping tools are now issued as M&TE equipment.
The crimpers are on a preventive maintenance program to keep them in calibration.
The licensee has also reviewed their procedures against Regulatory Guide 1.33 and has issued or has in draft, procedures to correct the violation concerning emergency procedures.
Based on the licensee's corrective action and the inspector's review, items 87-01-01 and 86-07-11 are closed.
(Closed) 86-13-01, "10 CFR 50.59 Reporting Requirements" This enforcement item identified weaknesses in the area of reporting to the NRC modifications made pursuant to 10 CFR 50.59.
The inspector had noted several modifications which were not reported within a year of the modification being implemented and which did not include the required summary safety evaluation in the report.
In its response to the Notice of Violation, the licensee committed to revising procedures to ensure a report to the NRC within one year or sooner of each change made pursuant to the provisions of 10 CFR 50.59 and to eliminate by September of 1986 a backlog of changes that had been completed but had not been reporte.
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The inspector reviewed Quality Control Instruction (QCI) No. 5, Revision 2, effective June 30, 1986, titled " Safety Review of Proposed Facility.
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Changes," and Quality-Assurance Implementing Procedure'(QAIP) No'. 10, c
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Revision 0,! effective-June 6l 1986,~ titled "QA 10 CFR 50.59 Review Procedure." -QCI No. 5 calls for site'QA to send a copy of the 10 CFR.
50.59 report, including the safety analysis ~and design basis report, tol
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the Regulatory Compliance Superintendent forzinclusion in a Monthly Operating Report to the NRC.
The revised procedure (Revision _2) altered the routing of the review package to facilitate more timely reporting of-
. 10 CFR.50.59 changes.
QAIP No. 10 was written.in response to the Notice of Violation and provides for the.use of a holdup list to be sent on a monthly basis to persons who are holding up 10 CFR 50.59 review packages.
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CFR 50.59 changes identified in the previous NRC inspection had
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subsequently been eliminated. The inspector reviewed a sample of 50.59,
changes and concluded that,the licensee was taking more timely actions in
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the repor. ting of 50.59 changes, e
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Based on the'above reviews', the inspector determined.that the licensee
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responded in a timely manner and has completed the corrective actio'ns
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This item is closed.
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(0 pen) 86-22-02, " Storage of Records in Vault"
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In a previous. inspection, the inspector found that completed surveillance records were kept in file drawers of one-hour fire rating in the Administration Building and. completed calibration test records were kept
in metal office file cabinets in the I&C Shop, and'not in file containers
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or a record storage facility that comply with record storage requirements l
of a minimum two-hour fire rating. This was identified as a violation of i
the licensee's QA procedure established to meet the 10 CFR 50, Appendix B
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Criteria XVII requirement on QA Records.
The cover letter which
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apparent result of the licensee's failure to take timely and
't comprehensive corrective action to a previously identified deviation in
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the area of records control, and that licensee attention to the adequacy
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of the corrective action program was. warranted.
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The licensee responded to this enforcement item in a letter dated i
September 26, 1986.
The inspector inspected the record storage vault in
the Training and Records Building and inspected the file cabinets and j
shelving in the Administrative Building and the I&C Shop.
The inspector:
verified that the following corrective actions as stated in the response j
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have been completed or are in progress:
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High density storage equipment, which will increase the storage-capability of the Training and Records Building vault, is being
procured.
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Quality Assurance Procedure 18, on records retention, was revised to j
describe an exception to the two-hour fire rated file container
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j requirement of NQA-1, Supplement 17S-1, in the local work areas.
i Newly generated records in local work areas will be stored for a
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maximum time period of 120 days in one-hour fire rated cabinets i
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prior to being microfilmed with dual storage of microfilm masters or
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stored in the record storage vault.
Administrative' Procedure 8 on records' management was revised to facilitate the process of microfilming QA records.
Training has been scheduled and an office memorandum from the Deputy General Manager has been issued to facilitate the timely processing and storage of records.
The backlog of records which have not been microfilmed or stored in the vault will be_ temporarily stored in'one-hour fire rated cabinets.
Licensee management has comm.itted to eliminate the development of any further backlog and to resolve the existing backlog by December of.1989.
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Although the licensee has completed a number of corrective actions, a number of open issues remain, and the inspector questioned whether the commitment to resolve,the existing backlog by December of 1989 constituted timely corrective action.
During its investigation of the circumstances surrounding the violation, the licensee found a number of engineering documents stored in a Sacramento warehouse.
An audit was completed to identify potential storage discrepancies, but the audit report had not been completed and distributed at the time of this inspection.
The revised procedures call for storage of records in one-hour rated filing cabinets in local work areas.
There are few one-hour rated filing cabinets-on site, and the licensee is actively working to procure the required n' umber of cabinets.
The request for exemption from the two-hour fire rated cabinet requirement of NQA-1, Supplement 175-1, in the local work areas has yet to be submitted as a revision of the QA Plan to the NRC.
The modification of the storage vault to incorporate high density storage shelving appears to require enhancement of the fire suppression capability for the vault.
The licensee's Fire Protection group has recommended the installation of a water sprinkler suppression system and ionization detectors to supplement the existing Halon system.
Finally, the inspector did not find documented records to show that the licensee has assessed the adequacy of its corrective action program in view of this violation.
Until further progress is identified on the above issues, this item will remain open.
7.
Temporary Instructions (Closed) Temporary Instruction (TI) 2515/69, " Steam Binding of AFW Pumps" This TI relates to bulletin 85-01, " Steam Binding of AFW Pumps".
The bulletin was closed in inspection report 86-07.
The inspector verified that the requirements of the TI had been met.
Based on the closure of the bulletin in the inspection report, this TI is close.
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Corrections to Previous Inspection Reports
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In two previous inspection reports (86-03 and 86-34), a list was provided
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-for issues relatingsto the Transamerica Delaval Incorporated (TDI)
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These lists collated NRC part 21 open item numbers, SMUD I.D.
Number, TDI Number, subject, resolution and status.
The item in question
.was reported in inspection report 86-34 as follows:
NRC Open TDI SMUD Item No.
I.D. No.
I.D. No.
Subject Resolution Status 86-07-P No. 131 No. 36 Lube oil Check Changed out Closed Valves to Buna N material
The correction to the list is as follows:
NRC Open TDI SMUD Item No.
I.D. No.
I.D. No.
Subject Resolution Status 86-10-P No. 131 No. 36 Lube oil Check Changed out Closed Valves to Buna N material 9.
Exit Meeting
An exit meeting was conducted on January 9,1987, with the licensee representatives identified in paragraph 1.
The inspectors summarized the s.
scope of the inspection and the findings as described in this report.
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Licensee representatives acknowledged the inspectors' licensee findings.
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