IR 05000309/1988007

Insp Rept 50-309/88-07 on 880421-0525.No Violations Noted. Major Areas Inspected:Followup on Previous Insp Finding, Review of Special Repts,Licensee Event Followup,Operational Safety Verification,Maint,Surveillance & Physical Security

ML20155J876
Person / Time
Site:	Maine Yankee
Issue date:	06/10/1988
From:	Lester Tripp NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20155J864	List: IR 05000309/1988007 ML20155J859
References
50-309-88-07, 50-309-88-7, NUDOCS 8806210058
Download: ML20155J876 (10)

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U.S. HUCLEAR REGULATORY COMMISSION Region I Report No: 50-309/88-06 License No: DPR-36 Licensee: Maine Yankee Atomic Power 83 Edison Drive Augusta, Maine 04336 Name: Maine Yankee Atomic Power Company Inspection At: Wiscasset, Maine Conducted: April 21 through May 25, 1988 Inspectors: Cornelius F. Holden, Senior Resident Inspector Richard J. Freudenberger, Resident Inspector

/2M AfUDb D 0Yb0 L~owell E. TM , Chief, date fru Reactor Pro ects Section 3A Summary: Inspection on April 21,1988 to May 25,1988 (Report Number 50-309/88-07 Areas Inspected: Routine resident inspections of plant operations including:

followup on previous inspection findings, review of special reports, licensee event followup, operational safety verification, maintenance, surveillance, physical security and radiation protectio Backshift inspections were con-ducted on April 23, 24, 25, May 17, 20 and 24, 198 Results: No violations or adverse findings were identifie Two initiatives, the Rework Tracking System and the Design Basis Review audits were note These programs appear to identify detailed items and correct them to prevent more significant difficulties in these area Two issues that continue to be followed are the Calorimetric Uncertainties (Section 4.b) and the Charging System Vent Valves (Section 12).

8806210058 880610 PDR ADOCK 05000309 Q DCD

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OETAILS 1. 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 start of the inspection period the plant was at 100 percent powe On April 29, power was reduced to 76 percent due to a malfunction in the Section 377 transmission line. Power was returned to 100 percent the same day after turbine valve and main steam excess flow check valve routine surveillance testing. The plant remained at 100 percent power

,ar the remainder of the report perio . Review of Licensee Event Reports (IP 90713)

The inspector reviewed the following Licensee Event Reports (LER) to determine that reportability requirements were fulfilled, immediate corrective action was taken, and corrective action to prevent recur-rence had been accomplished in accordance with Technical Specifications, LER 88-003 Safety System Motor Operated Valve (MOV) Non-Consetvative Thrust Values The licensee employed MOVATS Incorporated to perform motor operated valve testing during the 1987 outage. M0 VATS supplied minimum required MOV thrust values; however, the licensee utilized more conservative thrust values to establish the torque switch trip setpoint Subsequently, MOVATS expanded their database and improved their statistical analysis method which resulted in revised minimum thrust value recommendations to Maine Yanke The revised recommendations resulted in the two volume control tank outlet isolation motor operated valves to have setpoints which were less conservative than the setpoints established by the revised thrust valve The licensee informed the NRC Region I office by phone of his concern over the large change in the MOVATS recommended thrust values. An inspecti,n was conducted by a region-based specialist inspector on February 29 to March 4,1988, to gather information about this issu The findings of the inspection are documented in Region I Inspection Report No. 50-309/88-04 dated May 11, 198 Additionally, NRC Headquarters completed the review of Bulletin 85-03, item e, "Motor-Operated Valve Common Mode Failures During Plant Transients Due to Improper Swi+ch Settings." The licensee had identified the selected safety-re sted valves, the valves'

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-3-maximum differential pressures and the program to assure valve operability in their letters dated May 21, June 4, October 16 and December 22, 198 Review of these responses indicated the need for additional information which was requested in a letter dated July 29, 198 Review of the licensee's responses to this request for additional information indicates that the licensee's selection of the applicable safety-related valves to be addressed and the valves' maximum dif-ferential pressures meets the requirements of the bulletin and that the program to assure valve operability requested by action item e of the bulletin is now acceptabl LER 88-004 Potentially Degraded Fire Doors The licensee identified seven fire barrier doors which may not have performed their intended function under all circumstance The seven doors were all security doors operated by a solenoid latching devic It was postulated that an intense fire could have resulted in a failure of the wiring, de-energizing the solenoid latching mechan-ism, permitting the doors to unlatc This condition is contrary to National Fire Codes. Immediate corrective action in the form of a roving fire watch was established. Within six days of discovery all the doors were modified to remain latched on loss of power to the solenoid latching mechanism. The information provided in the LER was found to be complete and accurat No violations were identifie . Followup on Previous Inspection Findings (Closed) Unresolved Item 50-309/87-04-01 Review of Licensee's Steam Generator Chemistry Control and scope of ultrasonic inspection. A meeting was held on April 27, 1988 at the Region I office during which Steam Generator Chemistry Control and ultrasonic inspection criteria were discussed. Information presented during this meeting resulted in closure of this ite (Update) UNR 50-309/88-01-01 Unresolved Item concerning plant calorimetric uncertaintie The licensee committed to provide the NRC with an assessment of the span shift associated with Rosemount transmitters (models 1151DPGE22 and 11510P5E22) and the impact on the plant calorimetri In a letter dated April 29, 1988 (MN-88-48)

the licensee submitted " Quantification of the Maine Yankee Calori-metric Power Measurement Uncertainty". The review utilized two statistical techniques to combine the uncertainties associated with process measurements from the main steam and main feedwater system . .

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-4-The uncertainties on the process measurements input to the calori-metric were quantified using the Standard Rcat-Mean-Squaru technique to combine uncertainties associated with electrical hardware and instrumentation. These process measurement uncertainties were then assumed to be normally distributed and their combined affect on the overall calorimetric power level was quantified using the Monte Carlo simulation techniqu The uncertainties (at the 95/95 level of confidence) for the feedwater flow and steam flow calorimetric power measurements at 100 percent rated thermal power were less than 0.5 percent and 0.9 percent rated thermal power respectively. The analysis demonstrated that past plant opera-tions with a static offset bias of up to one percent of full power did not exceed the safety analysis uncertainty assumption of two percent associated with the measurement of power level. Additional review of this uncertainty analysis will be conducted by the NRC. The inspector had no further question . Operational Safety Verification (IP 71707)

On a daily basis during routine facility tours, the following were checked: manning, access control, adherence to procedures and LCO's, instrumentation, recorder traces, protective systems, control room annunciators, radiation monitors, emergency power source operability, control room logs, shift supervisor logs, and operating orders. On a weekly basis, selected engineered safety features (ESF) trains were verified to be operable. The condition of the plant equipment, radio-logical controls, security and safety were assessed. On a biweekly frequency the inspector reviewed safety-related tagouts, chemistry sample results, shift turnovers, portions of the containment isolation valve lineup and the posting of notices to worker Plant housekeeping and cleanliness were also evaluate The inspector observed selected phases of the plant's operations to determine compliance with the NRC's regulations. The inspector determined that the areas inspected and the licensee's actions did not constitute a health and safety hazard to the public or plant personne The following are noteworthy areas the inspector reviewed: The inspector reviewed the licensee's method of controlling the position of valves in accordance with Technical Specifications (T.S.) 3.6 and 4.6. These specifications require that emergency core cooling system (ECCS), emergency feedwater and auxiliary feedwater system manual valves be aligned and locked in their required positions and automatic valves be set for automatic initiation or be locked in their safeguards positio Valve positions for emergency and auxiliary feedwater are required to be checked monthl O

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-5-Maine Yankee utilizes a stainless steel wire and clip to lock valves in their required position. This meets the intent of the T.S. by physically restraining valve movement. Additionally, all ECCS, emergency and auxiliary feedwater valves are checked on a monthly basis for proper position. According to interpretation of locked valves in the NRC Inspection Manual, this method of valve control is acceptable. The inspector had no further question On May 24 the licensee was preparing to perform maintenance on motor operated valve PCC-M-43, which controls component cooling water flow to the "A" residual heat removal (RHR) heat exchanger, opening on receipt of a recirculation actuation signal (RAS). Prior to remov-ing PCC-M-43 from service, the motor operated valve, (SCC-M-165) in the "B" train was stroke tested. During this test SCC-M-165 opened properly but did not fully close. The licensee declared the valve inoperable and performed the necessary actions according to the Tech-nical Specification Remedial Actions. The valve failure was found to be due to a sheared reach rod roll pin. The pin was replaced and the limit switch and torque switch settings of the motor operator were checke SCC-M-165 was returned to service later the same da The licensee determined that the cause of the shear pin failure was elongation of the hole in the extension shaft to the valve operato A new shaft will be fabricated onsite and installed in the near futur No violations were identifie . System Alignment Inspection (IP 71710)

Operating confirmation was made of the post accident purge (PAP) syste Accessible valve positions and status were examined. Power supply and breaker alignments were checked. Visual inspection of major components was performed. Operability of instruments essential to system perform-ance was assessed. As-built diagrams were reviewed in conjunction with the operating procedures for the system. Several instances were identified where PAP valves were not incorporated into the operating procedures. Without control over the position of these valves the inspector believed that the valves could have been mispositioned and would not have been identified until the system was called upon to function. Examples of valves which were not included in the operating procedures are: PAP-11 (vent isolation valve), PAP-48 (hydrogen recom-biner tap isolation valve), PAP-50 (sample port isolation valve), PAP-52 (sample isolation valve) PAP-26,27,28, and 29 (root isolation valves to FI-3502 in the emergency feedwater pump room). None of these valves were found to be mispositioned. The consequences, if the talves had been mispositioned, were determined to be insignificant since end caps, blank flanges and other isolation valves were present in the affected lines. The licensee has agreed to review the operating procedures and make additions or changes as necessary to provide better control of the system's alignment. The inspector had no further questions, . .. .. .

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-6-7. Plant Maintenance (IP 62703)

The inspector observed and reviewed maintenance and problem investigation activities to verify compliance with regulations, administrative and main-tenance procedures, codes and standards, proper QA/QC involvement, safety tag use, equipment alignment, jumper use, personnel qualifications, radiological controls for worker protection, retest requirements, and reportability per Technical Specification Portions of the following maintenance evolutions were reviewed:

Discrepancy Date Report Number Description 4/28 1621-88 Duratek Liquid Waste Processing System Vessel Change Out 5/3 0653-88 Spent Fuel Pool Purification System Prefilter (FL-2)

5/6 1112-88 Containment Spray Pump (P-61A) Mechanical Seal Replacement 5/18 2123-88 Motor-Generator Set (MG-1A) Bearing Replacement 5/24 2416-88 Motor Operated Velve, SCC-M-165, Reach Rod Repair The insp: tor reviewed the Rework Identification and Corrective Action Program, procedure 5-216-5. The program provides for maintenance rework identification and corrective action follow-through. Upon determination that an item meets the criteria for review in this program, a Section Chief or higher makes an independent determination utilizing a minimum of three years of equipment history. Corrective action may be initiated prior to returning the system to service or the item may be tracked under an existing tracking system. Action plans to preclude recurrence are initiate This system appears to be effective in the identification and resolution of rework item No violations were identifie . Surveillance Testing (IP r_726)

The inspector observed parts of tests to assess performance in accordance with approved procedures and LCO' , test results, removal and restoration of equipment, and deficiency review and resolutio _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ -

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-7-Portions of the following surveillances were reviewed:

Date Procedure Number Title 5/10 3. CEA Exercising 5/18 3-6.2.1.36 Post Accident Containment Vent System, Containment H2 Detector 5/19 3.1.12 Post Accident Purge System Monthly Surveillance No violations were identifie . Observations of Physical Security (IP 71707)

Checks were made to determine whether security conditions met regulatory requirements, 25e 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 measures when require No violations were identifie . Radiological Controls (IP 71709)

Radiological controls were observed on a routine basis during the reporting period. Areas reviewed included organization and management, external radiation exposure control and contamination contro Standard industry radiological work practices, conformance to radiological control procedures and 10 CFR Part 20 requirements were observe Independent surveys of radiological boundaries and random surveys of nonradiological points throughout the facility were taken by the inspector. Additionally, Radiation Work Permit (RWP) 88-5-3 was reviewed in detail. This RWP controlled the work associated with the replacement of the spent fuel pool purification system pre-filter (FL-2). The inspector observed the replacement of the filter and had the following observations:

The spent filter was removed and placed directly in a high integrity container (HIC) for shipment. In the past spent filters of this type have been placed in a temporary storage container for some time prior to being loaded into a hlC in preparation for shipmen Placing the spent filter directly into a HIC prevents the need to handle the spent filter again to transfer it from the temporary storage container to the HIC, resulting in a significant reduction in overall worker radiation exposur The maintenance technicians appeared to be adequately prepared and had all the necessary tools available, however, they were not aware of the presence of a permanently installed cable that could be used to open the cover of the filter housing remotel The cover was opened using long

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-8-nandled tools, and the use of the cable was necessary to hold the cover open. While the cover was still open the maintenance technicians marked an appropriate position on the wall for the installation of a hook to be used in future filter replacements. A work order was initiated to install the hook. Not all of the filter housings of this type have cables to remotely open the covers. However, where they are installed, their use would aid in reducing worker exposure The health physics technicians provided adequate coverage for the main-tenance technicians performing the work, however, not all doors which accessed the room were controlled. Additional measures to prevent other plant workers from inadvertently entering the higher dose rate areas created during spent filter transfer might further enhance reduced exposure These issues were discussed with plant management. The inspector had no furthcr comment . Design Basis Review Program The licensee initiated a design basis review program in response to problems found in the industry with the inadequate control of the design of safety related system The design basis review program as implemented by Maine Yankee includes three key areas: 1) system walk-downs, including a review of plant procedures for routine operation and maintenance, 2) post modification testing of selected components to assure they meet the design basis, and 3) collection of documentation from original design documents to recent modification. Utilizing these sources of information the licensee developed a plan for conducting a design basis review of individual systems. The review is conducted by Yankee Atomic Electric Compan During the last operating cycle the auxiliary / emergency feedwater system received a design basis review, Corrective actions resulting from this review were tracked under the existing Commitment Management Syste The inspector reviewed the Design Basis Review Repor . Charging System Vent Valves As a part of the licensee's design basis review of the high pressure safety injection system (HPSI), a potential problem with the environ-mental qualification of four charging system vent valves was identifie The charging system pumps become the HPSI pumps during a safety injec-tion actuation signal (SIAS). During normal operation the charging system takes a suction on the volume control tank. The suction piping for both the A and B train to the charging pumps has a vent system to remove gases and prevent va- binding of the charging pumps. An SIAS starts both charging pumps HPSI pumps), aligns the suction of the pumps to the refueling water *orage tank (RWST) and isolates the vent

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system. The vent system utilizes four solenoid valves to accomplish this isolatio * . -

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. The potential problem involved the lack of qualification paperwork for the four solenoid valves. Without this paperwork the ability of the valves to withstand the high radiation levels in a post accident situation has not been established. During an accident sequence, the HPSI pumps take a suction on the RWST until the level reaches 100,000 gallons. HPSI suction is then aligned to the containment sump during recirculation actu;cio., signal (RAS). Worst case assumptions result in approximately 20 minutes before the RAS transfers the suction. It was during the rscirculation phase of the postulated accident scenario that radiation '.evels in the primary auxiliary building (PAB) would increase and pote,tially affect the vent system solenoid valve Yankes stomic Electric Company (YAEC) conducted the analysis of the radiation levels. This analysis showed that the radiation levels in the vicinity of the solenoid valves would probably exceed the limit of the valves three weeks after RAS. With a ten percent difference in the conservative assumptions that were applied to this analysis, the valves would be expected to perform for thirty day The inspector reviewed the electrical diagrams which supply power to the solenoid valves. The solenoid valves are energized to close. The four solenoid valves are supplied 125-volt DC power from battery bus 1 via distribution panel DP/P and battery bus 3 via distri iution panel DP/8 In the event of a failure of the solenoid valves such as an electrical short, SIAS would still occur even though the relay supplying power to the solenoid is controlled from the same device which causes SIAS. On a theoretical loss of power at the same time SIAS occurs, safety injec-tion would still occur. One function that is normally isolated on a SIAS (charging pump low suction pressure trip) would be reinstated earl The licensee took several actions to preclude potential problems areas including a procedure change which directs operators to shut the manual valves in the PAB and isolate the vent system after safety injection has occurred. Under the worst case scenario the operators will have twenty minutes to accomplish this action prior to RAS. Fuses were installed in the solenoid actuation circuit to prevent potential failures of the solenoids from affecting the rest of the Safety Injection Logic. All operators were instructed on these change The licensee currently plans to replace these valves with qualified solenoid valves. On May 23, 1988, the licensee determined that suffi-

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cient differential pressure could exist during the recirculation phase to allow high levels of radiation to flow into the vent area and affect the solenoid valves (provided they had some leakage) and reported the deficiency under Article 50.7 The resident inspector will continue to follow licensee's actions.

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-10-13. Exit Interview (IP 30703)

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Meetings were periodically held with senior facility management to discuss the inspection scope and findings. A summary of findings for the report period was also discussed at the conclusion of the inspectio The licensee did not identify 2.790 materia _______ _ _ _ ______ - _