IR 05000309/1986010

Insp Rept 50-309/86-10 on 860617-0728.No Violation Noted. Major Areas Inspected:Control Room,Plant Operations, Radiation Protection,Physical Security,Fire Protection & Plant Operating Records

ML20203K346
Person / Time
Site:	Maine Yankee
Issue date:	08/08/1986
From:	Lester Tripp NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20203K341	List: IR 05000309/1986010 ML20203K337
References
50-309-86-10, CAL-82-20, NUDOCS 8608200253
Download: ML20203K346 (8)

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' U.S. NUCLEAR REGULATORY COMMISSION Regio Docket / Report: 50-309/86-10 License: DPR-36 ,

Licensee: Maine Yankee Atomic Power i Inspection At: Wiscasset, Maine Dates: June 17 through July 28, 1986 i Inspectors: Cornelius F. Holden, Senior Resident Inspector Jeffrey Robertson, Resident Inspector D vid F. Limroth, Project Engineer Approved by:

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1. E. Trfp , Chief, Reactor Projects Section 3A h

' Date Summary: Inspection on June 17 - July 28, 1986 (Report No. 50-309/86-10)

l Areas Inspected: Routine resident inspection (282 hours0.00326 days <br />0.0783 hours <br />4.662698e-4 weeks <br />1.07301e-4 months <br />) of the control room, ac-t

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cessible parts of plant structures, plant operations, radiation protection, physi- l cal security, fire protection, plant operating records, maintenance and surveil-lanc Results: No violations were identified. Programmatic reviews were performed on the maintenance and surveillance areas (details in Sections 4d and 4e respectively)

with no significant finding ,

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DETAILS Persons Contacted Within this report period, interviews and discussions were conducted with various licensee personnel including plant operators, maintenance technicians and the licensee's management staf . Summary of Facility Activities At the beginning of the report period, power was being maintained at 85% while investigations were being conducted on the EFCV rupture disk failure (details in Section 8). The plant was shut down on June 30 to replace the rupture disks and to perform eddy current inspections of main condenser tubes. The tube inspection led to the discovery of additional problems with #2 LP turbine (details in Section 4.d) which extended the shutdown until July 18. The tur-bine was phased on the grid July 19 and power was increased in increments in order to observe the response of secondary systems. On July 24, the plant was at 98% power and remained there until the end of the report perio . Followup on Previous Inspection Findings (Update) Inspector Follow Item (50-309/82-26-03). Licensee commitment to identify and resolve any differences between plant operating para-meters and safety analysis assumptions. This commitment was in response to Action Item 5 of Confirmatory Action Letter 82-20. In a letter dated November 24, 1982, the licensee stated that they planned on developing a control system by mid-1983 to assure that operating parameters are maintained in the bounds of the safety analyses. Since that time, the Inputs and Assumptions Source Document (IASD) has been under development and the scope was expanded to encompass more than the original commitmen The IASD was reviewed and approved July 14,1986, and is currently being issued under controlled distribution. The IASD is guidance intended for use by plant personnel and safety analysts, to ensure operation within the safety analysis envelope and the use of appropriate assumptions in analyse Department procedures will be used to implement and control the use of the IASD, which will be required for design changes, procedure changes and safety analysis change Licensee management has committed to have the procedure changes required for implementation of this program by November 1,1986. The program and its results will be followed in a subsequent inspectio (Closed) Inspector Follow Item (IFI 50-309/86-01-03). Evaluation of the common recirculation line for the LPSI and spray pumps with respect to the single failure of the recirculation line check valv The licensee has committed to disassemble and inspect the common recirculation line l

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check valve (CS-53) during the next refueling outage scheduled to begin March 198 Discrepancy Report #1940-86 has been initiated to ensure this inspection is performe (Closed) Violation (NCS 50-309/86-01-01). A plant engineer operated a valve in the Auxiliary Feedwater _ System in order to obtain a pressure reading without the knowledge or authorization of the proper superviso A written directive was issued which prohibits PED personnel from mani-pulating valves without an approved procedure authorizing them to do s In the absence of an approved procedure, Operations Department personnel are responsible for valve manipulations that are required for engineering task . Routine Periodic Inspections Daily Inspection During routine facility tours, the following were checked: manning, ac-cess control, adherence to procedures and LCO's, instrumentation, recor-der traces, protective systems, control rod positions, Containment, tem-perature and pressure, control room annunciators, radiation monitors, radiation monitoring, emergency power source operability, control room logs, shift supervisor logs, and operating order System Alignment Inspection Operating confirmation was made of Emergency Diesel Generators fuel sup-ply and starting ai Accessible valve positions and status were.ex-amined. Power supply and breaker alignment was checked. . Visual inspec-tion of major components was performed. Operability of instruments es-sential to system performance was assessed. No discrepancies were note Biweekly Inspections During plant tours, the inspector observed shift turnovers, chemistry sample results and the use of radiation work permits and Health Physics procedures. Area radiation and air monitor use and operational status was reviewe Plant housekeeping and cleanliness were evaluate No discrepancies were note Plant Maintenance The inspector observed and reviewed maintenance and problem investigation activities to verify compliance with regulations, administrative and-maintenance procedures, codes and standards, proper-QA/QC involvement, safety tag use, equipment alignment, jumper use, personnel qualifications, radiological controls for worker protection, fire protection, retest re-quirements, and reportability per Technical Specifications.

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4 While the plant was shutdown for EFCV rupture disk replacement, eddy current testing was performed on selected condenser tubes. A visual inspection of the steam side of the condenser tubes was also done which revealed 55 dents in condenser tubes. Pieces of soft metal the size of pebbles were found in the condenser. Additionally, the

1. 2 Low Pressure Turbine, which is directly above the area of the dented tubes, was discovered to have a metal-to-metal scraping sound when placed on the turning gear. Westinghouse was called on site to evaluate the condition of the turbin During disassembly of the #2 LP Turbine, the licensee discovered one inner casing nut was missing and two others were cocked and damaged. The missing nut was found upon further disassembly and no turbine damage resulted from these problem The tube denting and metal-to-metal scraping sound were determined to be caused by seal strips in the upper casing of the turbin One seal strip was missing and several others damaged. These seal strips increase the efficiency of the machine by decreasing the leakage of steam between turbine stages. The missing seal strip accounts for the pieces of metal found in the condense Damage to the turbine blades was considered mino The outage was extended to July 18 in order to accomplish repairs to the #2 L.P. Turbin . The inspector reviewed the corrective and preventive maintenance programs to ensure that the licensee's programs are in compliance with Technical Specifications, regulatory requirements and commit-ments to industry standard The inspector verified that written procedures are established for initiating requests for maintenance; criteria and responsibilities for review and approval of maintenance requests have been estab-lished; criteria are established for determining whether the acti-vity is safety-related or non-safety related; appropriate hold points for inspection are provided; functional testing prior to returning the system component to service is performed; appropriate records are generated, reviewed and maintained; and procedures re-quire, where appropriate, special authorization for activities in-volving risk of fir No concerns were identifie e. Surveillance Testing and Calibration Control Program i The inspector reviewed the surveillance program to ascertain that the licensee has implemented programs for control and evaluation of surveillance testing, calibration and inspection required by Technical Specifications and calibration of instrumentation associ-

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ated with safety-related equipment not specifically addressed by

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Technical Specifications. The inspector verified that a schedule  ;

y for surveillance testing and calibration required by Technical- '

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Specifications has been established including frequency, responsi-

bility and test status; responsibility is assigned for maintaining j the schedules and that revisions are incorporated into the surveil- ,

- lance schedules; formal requirements have been established for the .

conduct of surveillance tests, calibrations, and inspections in ac- '

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cordance with approved procedures including acceptance criteria; and, responsibilities are defined for review and evaluation of sur-veillance test / calibration data including procedures for reporting

, deficiencies and verification that limiting conditions for operation are satisfied.

} The inspector observed portions of tests, including the following, to assess performance in accordance with approved procedures and LCO's, test results, removal and restoration of equipment, and de-i ficiency review and resolution:

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DG 1A monthly

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DG 1B monthly

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SCC Pump (P108) vibration testing i

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Hands on training of new auxiliary operators in the performance of surveillance testing was observed. Instructions included precau-l tions, communications, adherence to procedures and expected system j response The training observed was thorough and no concerns were identifie . Observations of Physical Security

Checks were made to determine whether security conditions met regulatory re-I quirements, the physical security plan, and approved procedures. Those checks included security staffing, protected and vital area barriers, vehicle searches and personnel identification, access control, badging, and compensatory meas-j ures when require ! On July 8, in accordance with'10 CFR 73.71, the licensee reported a moderate loss of physical security effectiveness. At 12:59 the Honeywell access com-

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puter system failed to function in the alarm and recording modes. Compensa-j tory measures were.in place for vital areas within 3 minute Honeywell was called on site and the system was rebooted and operational at 15:20.

On July 17, a security guard inadvertantly. fired a live round into a wall in-the security training room. No injuries resulted and the bullet-did not

! penetrate the wal Training was being conducted using dummy rounds. A live 1 '

round was inadvertantly mixed with the dummy rounds. .The resident inspectors reviewed the licensee's investigation and corrective actions 'and found them

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to be prompt and adequate.

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6. Radiological Controls -

Radiological controls were observed on a routine basis during the reporting ,

period. Standard industry radiological work practices, conformance to radio-logical control procedures and 10 CFR Part 20 requirements were observe Independent surveys of radiological boundaries and random surveys of nonradio-logical points throughout the facility were taken by the inspecto An independent swipe survey was performed in the Primary Auxiliary Buildin The swipes were counted by an HP Technician at the control point. Surveys, counting methods, and posting criteria were discussed with the technicians and were consistent with plant procedures. No discrepancies were note . Emergency Feedwater Pump On July 9, an Emergency Feedwater Pump (P-25C) was declared inoperable when it would not start for testin The pump failure was determined to be caused by crimped control power contacts on the charging spring motor for the 4160 Volt breaker. The pump was last operated on June 13, and it is believed that when the pump was secured the charging spring motor failed to operate pre-venting the breaker from closing on demand. A seven-day LCO is associated with an inoperable Emergency Feedwater Pump; however the plant had been shut-down since June 30 for maintenanc All 4160- and 6900-volt breakers were racked out and inspected for indications of crimped or damaged secondary contacts by maintenance and QC personne No additional problems with the secondary contacts were identifie . Excess Flow Check Valve (EFCV) Rupture Disk Replacement In order to determine the cause of the rupture disk failure that resulted in a reactor trip on June 12, the licensee put a strip chart recorder on the air supply to the operating cylinders of the EFCVs. After several days of opera-tion, it was determined that the "B" air compressor motor contacts intermit-tently stick closed causing pressure to increase above the set point. These contacts were replaced in both air compressor motors. The relief valves on the air system were removed and bench tested. The as-found lift pressure points were determined to be 145 and 155 psig. Rupture disk design pressure is 150 psig. The relief valves were reset to lift at 135 psig and reinstalle The plant was shutdown on June 30 to replace the rupture disks with a dif- i

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ferent styl The new style will permit the rupture disks to be installed into their assembly in the shop. This will facilitate a clean installation and even torquing of the assembl A test rig was set up in order to determine the variance in the rupture pres-sure of the disks previously used. The licensee also sent an engineer to the rupture disk manufacturer to test the new style of rupture disks to be use This was done to determine the effects of temperature, cleanliness, and torquing on the rupture pressure. Results of these tests indicate the new ;

style rupture disk's reliability to rupture at the design pressure. The lic-

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ense'e's investigation of the cause of the premature failure of the rupture disks was extensive and, in addition to the actions described above, also resulted in longer term recommendations for design review Rupture disk installation was completed and tested satisfactoril . 115-KV Offsite Power The inspector witnessed the reactor startup on July 18, 1986. When the third reactor coolant pump (RCP) was started in preparation for the reactor startup, a low voltage alarm on the 115-KV line was received. At the time of the RCP start, Section 207 of the 115-KV line was removed from service for maintenanc Section 69 (the other 115-KV supply line) voltage remained at 112-KV following the RCP start. The operators requested the dispatcher raise the 115-KV volt-age. The dispatcher was required to place Section 209 back in service in

, order to raise voltag During a normal shutdown period, the 115-KV line is the only form of offsite powe Backfeeding of the 345-KV line is available but requires the use of lengthy backfeed procedures. Low voltage on the offsite power supply could lead to higher currents in operating equipment and a potential for self-heat-ing damage to those motors. Panel Alarm procedures require the operators to determine the cause of the low voltage and correct it. In this case, the operators discussed the situation with the dispatcher who returned Section 207 and cleared the alar The inspector discussed this situation with the license The licensee is investigating the situation and the inspector will review the corrective actio . Feedwater System Review The licensee conducted an in-depth review of the feedwater system in order to better understand the effect of the various control systems on overall feedwater reliabilit This review process utilized outside consultants and the Plant Engineering staff. The review conducted an evaluation of the Heater Drain Tank level control, main feedwater regulating valves and all feedwater pump control, trip and recirculation valve control circuits. Other portions of the study are continuing including a fault-tree analysis of the steam driven feedwater pum Some recommendations have resulted from the feedwater system stud These include the use of replacement controllers for the original controllers (parts for the original controllers are no longer available) and the operation of the steam driven feedwater pump (P-2C) in the pressure control mode. The pressure control mode was used for P-2C during the recent plant startup (plant had recently utilized the speed control mode of P-2C in order to eliminate failures of the pressure controller from affecting feedwater flow).

The inspectors will continue to monitor the licensee's feedwater reliability progra ?

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1 Review of License Event Report (LER)

The inspector reviewed the following LER to verify that the details were clearly reported, including accuracy of the description of cause and adequacy of corrective action. The inspector had previously verified that appropriate corrective action was taken or responsibility assigned and that continued operation of the facility was conducted in accordance with Technical Specifi-cations and did not constitute an unreviewed safety question as defined in 10 CFR 50.59. No discrepancies were identifie LER # SUBJECT 86-03 Plant Trip on Low Steam Generator Level Due to Excess Flow Check Valve Closure 1 Exit Interview Meetings were periodically held with senior facility management to discuss the inspection scope and findings. A summary of findings was presented to the licensee at the end of the inspection. Preliminary inspection findings were discussed with licensee management periodically during the inspectio A summary of findings for the report period was also discussed at the conclu-sion of the inspectio ,

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