IR 05000237/1986004
| ML17199F744 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 04/28/1986 |
| From: | Boyd D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML17199F743 | List: |
| References | |
| 50-237-86-04, 50-237-86-4, 50-249-86-05, 50-249-86-5, NUDOCS 8605020062 | |
| Download: ML17199F744 (8) | |
Text
U. S. NUCLEAR REGULATORY COMMISSION REGION I II Reports No. 50-237/86004(DRP); 50-249/86005(DRP)
Docket No ~ 50-249 Licenses No. DPR-19; DPR-25 Licensee:
Commonwealth Edison Company P. 0. Box 767 Chicago, IL 60690 Facility Name:
Dresden Nuclear Power Station, Units 2 and 3 Inspection At:
Dresden Site, Morris, IL Inspection Conducted:
February 14 through April 15, 1986 Inspectors:
L. G. McGregor S. Stasek E. A. Hare
- fi~
Approved By:
D. C. Boyd, Chief Projects Section 2D Inspection Summary q'-28-86 Date Inspection during the period of February 14 through April 15, 1986 (Reports No. 50-237/004(DRP); 50-249/005(DRP))
Areas Inspected:
Routine unannounced resident inspection of previous findings, Regional request, operational safety, events, maintenance, surveillances, licensee event reports, and I. E. Bulleti Results:
Of the eight areas inspected, no violations of NRC requirements were identifie..
PDR ADOCK 05000237 l __ <!__
PDRY J~ *.
DETAILS Persons Contacted Commonwealth Edison Company
- D. Scott, Station Manager J. Wujciga, Production Superintendent R. Flessner, Services Superintendent
- T. Ciesla, Assistant Superintendent, Operations R. Zentner, Assistant Superintendent, Maintenance
- J. Brunner, Assistant Superintendent, Technical Services R. Christensen, Unit 1 Operating Engineer
- J. Almer, Unit 2 Operating Engineer J. Kotowski, Unit 3 Operating Engineer W. Pietryga, Unit 3 Operating Engineer for Recirc. Piping Replacement J. Achterberg, Technical Staff Supervisor D. Adam, Compliance Administrator J. Doyle, Q.C. Supervisor D. Sharper, Waste Systems Engineer S. McDonald, Radiation Chemistry Supervisor J. Mayer, Station Security Administrator W. Johnson, Chemistry Supervisor J. Schrage, Radiation Protection Supervisor
- P. Lau, Q.A. Supervisor R. Stobert, QA Inspector H. Cobbs, QA Inspector The inspectors also talked with and interviewed several other licensee employees, including members of the technical and engineering staffs; reactor and auxiliary operators, shift engineers and foremen, electrical, mechanical and instrument personnel, and contract security personne *Denotes those attending one or more exit interviews conducted on and informally at various times throughout the inspection perio Action on Previous Inspection Findings (Closed)
Open Item (237/83007-0l(DRP); 249/83006-0l(DRP)):
Potentially Generic Issue - Failure of Chicago Bridge and Iron (CB&I) Airlocks at the Rancho Seco Station and Applicability to Dresde In response to this item, Commonwealth Edison's Station Nuclear Engineering Department (SNED)
performed a review of the associated Licensee Event Report submitted by Rancho Seco on this matter and determined that:
(1), Rancho Seco had not properly maintained the subject airlocks; (2), training related to door operation there was inadequate; and (3), the audible alarm was not functioning at the time to alert the operators at Rancho Seco to the abnormal conditio Because of these conditions and the fact that the airlocks at Rancho Seco were electrically interlocked at the time while Dresden employs a mechanical interlock scheme, SNED concluded that the Rancho Seco incident was not applicable to Dresde The inspector agrees
with the licensee 1 s determination on this matte This item, therefore, is considered close (Closed)
(237/86001-0l(DRP); 249/86001-0l(DRP)):
A Problem Recently Identified at the Browns Ferry Plant Which Involved One of Its Emergency Diesel Generators (EDGs) When Cracking Was Discovered in the Diesel Accessory Drive Housing Assembl In response to this item, walkdowns of the Unit 2, Unit 3 and Unit 2/3 (Swing) EDGs were conducted and revealed that no visual indications of cracking were note During the annual maintenance of 2/3 (Swing) diesel (March 4, 1986), this aluminum housing was examined on both side Ninety-seven bolt holes were visually examined for indications of crackin No indications were note.
Operational Safety Verification The inspectors observed control room operations, reviewed applicable logs and conducted discussions with control room operators during the period from February 14 to April 15, 198 The inspectors verified the operability of selected emergency systems, reviewed tag9ut records and verified proper return to service of affected component Tours of Unit 2 and 3 reactor buildings and turbine buildings were conducted to observe plant equipment conditions, including potential fire hazards, fluid leaks, and excessive vibrations and to verify that maintenance requests had been initiated for equipment in need of maintenanc During the inspection period while Unit 3 was in an extended outage for refueling and recirculation piping replacement, the inspectors verified that surveillance tests were conducted, containment integrity requirements were met, and emergency systems were available as necessar The inspectors, by observation and direct interview, verified that the physical security plan was being implemented in accordance with the station security pla The inspectors observed plant housekeeping/cleanliness conditions and verified implementation of radiation protection control During th inspection, the inspectors walked down the accessible portions of the following systems to verify operability by comparing system lineup with plant drawings, as-built configuration or present valve lineup lists; observing equipment conditions that could degrade performance; and verified that instrumentation was properly valved, functioning, and calibrate Unit 2 Isolation Condenser Standby Liquid Control system Control Rod Drive Hydraulic System Reactor Protection System Power Supply
- The inspectors reviewed new procedures and changes to procedures that were implemented during the inspection perio The review consisted of a verification for accuracy, correctness, and compliance with regulatory requirement The inspectors also witnessed portions of the radioactive waste system controls associated with radwaste shipments and barrelin These reviews and observations were conducted to verify that facility operations were in conformance with the requirements established under technical specifications, 10 CFR, and administrative procedure No violations or deviations were identified in this are.
Followup of Events During the inspection period, the licensee experienced several events, some of which required prompt notification of the NRC pursuant to 10 CFR 50.7 The inspectors pursued the events onsite with licensee and/or other NRC official In each case, the inspectors verified that the notification was correct and timely, if appropriate, that the licensee was taking prompt and appropriate actions, that activities were conducted within regulatory requirements and that corrective actions would prevent future recurrenc The specific events are as follows: Rec~nt inspections of the Unit 2 drywell by the resident inspector indicated that certain electrical cables exhibited degr~dation of the outer sheath This degradation is evidenced by cracks, portions have come off and, in general, the cable is very brittle, mainly from prolonged high temperature condition Furthermore, the condition of the inner insulation operability is questionable, especially during elevated temperatures and moisture conditions which can exist within the drywell during accident condition In conjunction with the brittle cable conditions numerous liquid tight (seal tight) flexible conduits were broken (pulled apart exposing internal wiring) and the outer liquid tight sheathe was also brittle and, in many cases, had fallen of Pictures have been taken of these conditions and submitted to the Licensee and to Region II The licensee has scheduled a repair of these circuits by:
(1)
Prioritizing the circuits which need repair with regards to safety significanc (2)
Replacing liquid tight conduits with environmentally qualified conduit (3)
Checking routing of liquids to assure maximum protection from future physical damag This item remains an unresolved item until information becomes available with regard to which circuits are degraded and to what extent (50-237/86004-01).
4 During a followup inspection of environmentally qualified electrical wire for Unit 2 and 3 penetrations, it was noted that General Electric 11 Vulkene SIS" wire was being used within the drywel This wire is located in non~water or moisture tight junction boxes adjacent to the electrical penetration In most cases, the junction box covers (approximately 3 foot by 4 foot) are installed without a gasket and without a minimal number of bolts holding the covers in plac One junction box had an open 3 inch conduit hole on the sid The envi-ronmental qualification of this G. E. Vulkene SIS wire and the non-water tight junction boxes remains an unresolved item pending the licensee's evaluation of this wiring condition (50-237/86004-02; 50-249/86005-02). Vermont Yankee recently experienced prob 1 ems with their standby liquid control (SBLC) squib valve trigger assemblie During their annual surveillance of the SBLC system, both of the installed trigger assemblies failed to fir The investigation revealed that the cause of the event was a misalignment of the internal wiring of the trigger assembl The trigger assemblies have 4 electrical connectors (pins) labeled 1 through 4 in a counter-clockwise rotatio According to data supplied by Conax Corp., the manufacturer of the component, the 1 and 4 pin should be internally connected by a bridgewire and pins 2 and 3 should be internally connected by a bridgewire~ The investigation revealed that the bridgewires were connected between 1 and 2, and 3 and Conax Corp. identified 6 trigger assemblies stored on site at Dresden as potentially having the same proble The serial numbers identified were 546, 547, 548, 549, 550, and 55 On January 16, 1986, one of the trigger assemblies (serial number 551) was successfully test fired in accordance with Procedure DTS 1100- The remainder of the trigger assemblies identified by Conax were still in the storeroo The trigger assemblies installed in Unit 2 and Unit 3 are from a November 1981 batch (Purchase Order No. 734049, Serial Nos. 209 through 214).
No concern was raised about these trigger assemblies:
On March 12, 1986, the remaining trigger assemblies identified by Conax (SeriaJ Nos. 546 through 550) were tested for proper internal wiring in accordance with Special Procedure 86-2-2 Proper internal wiring and bridgewire resistance was observed by members of the Technical and Quality Control Staff and the Resident Inspecto The pin designation used at Dresden is different from the designation used at Vermont Yanke Dresden designates its pins with letters A through D in a clockwise rotatio Therefore, continuity was found between pins A and B, and C and Based on this investigation, Dresden sho~ld not experience the same problem that occurred at Vermont Yanke No further action relative to this problem is necessar * An Unusual Event was declared at 5:05 pm, on April l, 1986, after it was determined that all main control room panels for Units 2 and 3 were not installed according to the design drawing The bottom of each control room panel was not bolted to the support beams as
_
designed, but merely rested on top of the The licensee has since bolted and welded the panels to the support beam The seismic quali-fication of the installed bolts and welds remains an unresolved item pending the licensee's final evaluation of the new installation (50-237/86004-03).
No violations or deviations were identified in this are.
Monthly Maintenance Observation Station maintenance activities of safety related systems and components listed below were observed/reviewed to ascertain that they were conducted in accordance with approved procedures, regulatory guides and industry codes or standards and in conformance with technical specification The following items were considered during this review:
the limiting conditions for operation were met while components or systems were removed from service; approvals were obtained prior to initiating the work; activities were accomplished using approved procedures and were inspected as applicable; functional testing and/or calibrations were performed prior to returning components or systems to service; quality control records were maintained; activities were accomplished by qualified personnel; parts and materials used were properly certified; radiological controls were implemented; and, fire prevention controls were implemente Work requests were reviewed to determine status of outstanding jobs and to assure that priority is assigned to safety related equipment maintenance which may affect system performanc The following maintenance activity was observed/reviewed:
Unit 2 Emergency Diesel Unit 3 Emergency Diesel Unit 2/3 (Swing) Emergency Diesel Change Grease in six (6) Limitorque Valves No violations or deviations were identified in this are.
Monthly Surveillance Observation The inspectors observed surveillance testing required by technical specifications for the following item and verified that testing was performed in accordance with adequate procedures, that test instrumen-tation was calibrated, that limiting conditions for operation were met, that removal and restoration of the affected components were accomplished, that test results conformed with technical specifications and procedure requirements and were reviewed by personnel other than the individual directing the test, and that any deficiencies identified during the testing were properly reviewed and resolved by appropriate management personne The inspectors also witnessed portions of the following test activities:
Unit 2 T~aversing Incore Probe (TIP) System Operation (DOP 700-6).
No violations or deviations were identified in this are.
Licensee Event Reports Followup Through direct observations, discussions with licensee personnel, and review of records, the following event reports were reviewed to determine that reportability requirements were fulfilled, immediate corrective action was accomplished, and corrective action to prevent recurrence had been accomplished in accordance with technical specification Unit 2 (Closed)
86001-00 Reactor SCRAM on Greater Than 10% Stop Valve Closur The licensee investigation indicated that an erroneous high water level s)gnal resulted when an Instrument Mechanic was valving the emergency core cooling system yarway level indicating switch high-side test tap opene Corrective action was to order new instrument valve block manifolds to replace those currently being use (Closed)
86002-00 Failure to Pump Orywell Sump The event was caused by personnel error and equipment malfunctio As corrective action, the broken horn was fixed and the operators were made aware of their erro (Closed) 86003-00 Failure to Pump Drywell Sumps Within the Required Surveillance Interva The event was caused by personnel error and equipment failur As corrective action, the horn was replaced and the operators were made aware of their erro (Closed) 86004-00 Violation of Core Thermal Power Limi The licensee investigation determined that the 2C reactor feed pump flow transmitter was out of calibratio Corrective action was to install a protective barrier around the feedwater flow transmitte A supplemental report will be issued when a final decision has been mad (Closed) 86005-00 Reactor SCRAM on Low Condenser Vacuum and Mode Switch in 11 Run 11 *
The cause of the Scram was attributed to a faulty mode switc As corrective action, new-design mode switches have been ordered for Units 2 and 3:
(Closed)
86006-00 Failure to Pump Orywell Sumps During Surveillanc The cause of this event was personnel erro As a corrective action, the operator was made aware of the erro........
Unit 3 (Closed) 86002-00 Automatic Initiation of Standby Gas Treatment System (SBGT).
The licensee investigation determined that the_ initiation of SBGT was due to a loss of a r~diation monitcir power supply on the Reactor Protection System Bus Power Supply Transfe Corrective action included procedural changes and discussions in the six week operator training session The preceding LERs have been reviewed against the criteria of 10 CFR 2, Appendix C, and when the incidents described meet all of the following requirements, no Notice of Violation is normally issued for that ite The event was identified by the licensee, The event was an incident that, according to the current enforcement policy, met the criteria for Severity levels IV or V violations, The event was appropriately reported, The event was or will be corrected (including measures to prevent recurrence within a reasonable amount of time), and The event was not a violation that could have been prevented by the licensee's corrective actions for a previous violatio No violations or deviations were identified in this are.
Report Review During the inspection period, the inspectors reviewed the licensee's Monthly Operating Reports for January, February, and March 198 The inspectors confirmed that the information provided met the requirements of Technical Specification 6.6.A.3 and Regulatory Guide 1.1.
Exit Interview The inspectors met with licensee representatives (denoted in Paragraph 1)
informally throughout the inspection period and at the conclusion of the inspection on April 15, 1986, and summarized the scope and findings of the inspection activitie The inspector also discussed the likely informational content of the inspection report with regard to documents or processes reviewed by the inspector during the inspectio The licensee did not identify any such documents/processes as proprietar The licensee acknowledged the findings of the inspectio