IR 05000213/1992020
| ML20126B404 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 12/15/1992 |
| From: | Doerflein L NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20126B386 | List: |
| References | |
| 50-213-92-20, NUDOCS 9212220077 | |
| Download: ML20126B404 (26) | |
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U.S. NUCLEAR REGULATORY COMMISSION
REGION I
Report No.
50-213/92-20 License No.
DPR-61 Licensee:
Connecticut Yankee Atomic Power Company P. O. Box 270
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Hartford, CT 06141-0270 Facility:
Haddam Neck Plant Location:
Haddam Neck, Connecticut inspection Dates:
October 5,1992, to November 14, 1992 Inspectors:
William J. Raymond, Senior Resident inspector Peter J. Habighorst, Resident inspector L E i Az Approved by:
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Lawrence T. Doerflein, Chief Date Reactor Projects Section No. LA Areas Inspected:
NRC resident inspection of plant operations, radiological controls, maintenance, surveillance, licensee self-assessment, and periodic reports.
Inspection initiatives selected were CYAPCO's actions to ineet NRC Bulletin 88-08, " Thermal Stresses in Piping Connected to Reactor Coolant Systems," the Operational Experience Feedback -
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Program, and the General Employee Training-Program. The CYAPCO probabilistic risk assessment for 'Haddam Neck was used to select risk-significant components for inspection.
Results: ' See Executive Summary.
9212220077 921216-PDR ADOCK 05000213'
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EXECUTIVE SUSI A1ARY llADDAM NECK PLANT INSPECTION 92-20 Plant Operniatu The inspectors noted safe operation during the period and determined operators performed routine duties very well. Operator actons were prompt and effective to mitigate a water hammer in the auxiliary feedwater (AFW) piping. Plant system configurations were maintained as required by the technical specifications and important safety components as designated by the Haddam Neck probalilistic risk assessment were satisfactorily controlled.
The inspectors also found the posting and control of radiation hazards for routine activities were satisfactory. The general employee training program session conducted on October 19 was of excellent quality.
A quarterly emergency plan mini-drill conducted on November 5 was satisfactory in meeting the stated objectives. Actions to track the status of contracts for seismic information could be improved.
Maintenance and Surveillance The inspectors determined the performance by maintenance personnel to repair a diesel air filter and to replace faulty AFW hoses was very good. Actions to investigate degraded AFW hoses and to identify the failure mechanism were prompt and effective. Workers showed a high regard for the administrative controls and assured that work performed was in accordance with the documented work scope. Actions were not timely to address a longstanding maintenance item
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on a boric acid filter pressure instrument; a design change is planned. Surveillance and test activities observed were performed well and with a good regard for plant safety. The procedures for testing the safety bus undervoltage trip logic are satisfactory.
Et,gineering and Technical Support The inspectors determined engineering support was aggressive, thorough, and effective in resolving the degraded AFW hydraulic hose issue. This included assessing AFW operability,
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replacing the degraded hoses, and addressing root causes. The degraded condition highlighted l
an inadequate design review for the new hydraulic skids, which resulted from an over-reliance I
on a vendor's recommendation.
Engineering support to plant operations was also determined to be very good in meeting the commitments made in response to IEB 88-08 for monitoring thermal stresses in piping interconnected with the reactor coolant system. Additional NRC review is warranted to. follow the licensee's engineering evaluations for the AFW pipe stresses following a water hammer event (Section 2.2.1), and to evaluate the generic implications regarding the use of Houghto-Safe 620 L
hydraulic fluid (Section 6.2).
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Safety Assessment and Ouality Verification CYAPCo's conservative approach to safe plant operation was demonstrated by_ the action.to declare both auxiliary feedwater trains inoperable based on the potential for a common mode failure involving degraded hydraulic hoses. An excellent safety perspective was also shown by following up on the deficiency as it applied to Millstone 1 and assuring successful resolution.
Actions to address a potential deficiency in filters used for the lladdam Neck diesel auxiliary air system were also satisfactory.
The inspectors found licensee actions in the 1987-1989 period were comprehensive and mostly
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effective to address industry events identified by the operating experience feedback program, However, three operational issues in 1991 might have been prevented by a more timely or thorough action in response to events at other facilities. Further NRC review is warranted in this area to determine whether a weakness exists in the engineering review of issues identified by NRC Information Notices (Section 7.2).
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TABLE OF CONTENTS 1.0 -
SUMM ARY OF FACILITY ACTIVITIES..,,....................
I 2.0
- PLANT OPERATIONS (71707 and 93702).......................
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2.1 Operational Safety Verincation I
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2.2 Follow-up of Events Occurring During Inspection Period 3.
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2.2.1 Auxiliary Feedwater Pump Water Hammer...............
2.3 Procedure for Responding to Natural Disasters.......,...,.....
3.0 RADIOLOGICAL CONTROLS (71707)
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3.1 General Employee Training
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4.0 MAINTENANCE AND SURVEILLANCE (61726,62703 and 71707).......
4.1 Maintenance Observation..............................
4.2 Surveillance Observation
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5.0 EMERGENCY PREPAREDNESS (71707)
.......................10 5.1 Quarterly Emergency Plan Mini-Drill 10'
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6.0 ENGINEERING AND TECHNICAL SUPPORT (71707).......
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6.1 Thermal Stresses in Piping Connected to the Reactor Coolant System 11 1
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6.2 Auxiliary Feedwater (AFW) Pump Hydraulic Hoses
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7.0 SAFETY ASSESSMENT AND QUA'LITY VERIFICATION (40500, 71707, 90712, and 92701)
......................................-15 7.1 Plant Operations Review Committee....................... 15 7.2 Operational Experience Feedback Program................... 16 7.3 Follow-up of Previous Inspection Findings
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7.3.1 (Closed) IF150-213/92-15-04: ESAS Undervoltage Trip Scheme-. 18-
- 7.3.2 (Closed) - UR150-213/91-12-01: Pressurizer -Level Technical Specification......................
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7.3.3 (Open) URI 50-213/92-14-02: Electrical Housekeeping Practices.. 18 -
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Review of Part 21 Notification - Air Filters................... 19-
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8.0 EXIT MEETINGS
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Note: The NRC _ inspection manual procedure or temporary instruction that was insed as inspection guidance is listed for each applicable report section.
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DETAILS LO SUMMARY OF FACILITY ACTIVITIFS The unit remained at full power throughout the inspection period. The major operating issue during the period was the removal of both auxiliary feedwater trains from service due to degraded hydraulic hoses. An emergency plan mini-drill was satisfactorily conducted on November 5,1992. A meeting was held at the East Lyme Community Center on November 5, 1992, to obtain public comments on the Northeast Utilities Performance Enhancement Plan for Millstone and lladdam Neck.
2.0 PLANT OPERATIONS (71707 and 93702)
In addition to normal utility working hours, the inspectors routinely reviewed plant operations during portions of backshifts (evening shifts) and deep backshifts (weekend and night shifts).
Inspection coverage was provided for 25 hours2.893519e-4 days <br />0.00694 hours <br />4.133598e-5 weeks <br />9.5125e-6 months <br /> during backshifts and 13 hours1.50463e-4 days <br />0.00361 hours <br />2.149471e-5 weeks <br />4.9465e-6 months <br /> during deep backshifts.
2.1 Operational Safety Verification This inspection consisted of selective examinations of control room activities, operability reviews of engineered safety feature systems, plant tours, review of the problem identification systems, and periodic attendance at planning meetings. Control room reviews consisted of verification-of stafting, operator procedural adherence, operator cognizance of control room alarms, control of technical specification limiting conditions of operation, and electrical distribution verifications.
Administrative control procedure -(ACP) - 1.0-23, " Operations Department Shift Staffing Requirements," identifies the minimum staffing requirements. During the inspection ppriod, the inspectors noted the number of operators in the control room during power operations met these requirements.
The inspectors reviewed the onsite electrical distribution system to verify proper electrical lineup _
of the emergency core cooling pumps and valves, the emergency diesel generators, radiation.
monitors, and various engineered safety feature equipment. The inspectors also verified proper valve lineups, position of locked manual valves, power supplies, and flow paths for the high pressure safety injection system, the low pressure safety injection system, the containment air
- recirculation system, the service water system, and the emergency diesel generators.
No deficiencies were noted.
Jumpers and Tagonts The inspectors reviewed bypass jumpers against the requirements of ACP 1.2-14.1, " Jumper, Lifted Lead, and Bypass Control," with emphasis on proper installation and the content of the
safety evaluations.
The inspector reviewed all jumpers for age, and verified that Iflant-j
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Operations Review Committee (PORC) evaluations were completed to disposition longstanding j
evaluations.
The jumpers reviewed were found to be in accordance with administrative j
requirements.
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The inspectors reviewed equipment tagouts against the requirements _of ACP 1.2-14.2,
" Equipment Tagging." The inspectors verified that the proper equipment was tagged, equipment identified within technical specifications was appropriately controlled, and equipment isolation was proper based on work observations, controlled drawings, and procedural guidance. Tagouts reviewed were:
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" Pressurizer Low Pressure Relief," 920164
"B Station Air Compressor," and 92-03995 " Control Room Ventilation Louver." The inspectors also reviewed other tagging operations by comparing the tags installed within the plant with the tagout sheets maintained in the control room. Equipment reviewed was appropriately isolated and the tagouts met the technical specification requirements and administrative controls.
Log-Keeping and Turnovers The inspectors reviewed control room logs, night order logs, plant information report logs, and crew turnover sheets. No discrepancies or unsatisfactory conditions were noted. The inspectors observed crew shift turnovers and determined they were satisfactory, with the shift supervisor controlling the turnover. Plant conditions and evolutions in progress were discussed with all members of the crew. The information exchanged was accurate. The inspectors also reviewed control room trouble reports for age, Connecticut Yankee Atomic Power Company (CYAPCo)-
planned action, and operator awareness of the reason for the trouble report. Most trouble reports reviewed were recent, with few longstanding items.
During attendance at daily planning meetings, the inspector noted discussions were held on maintenance and surveillance activities in progress, and work control and authorizations. The inspectors conducted periodic plant tours in the primary auxiliary building, turbine building, and intake structures. Plant housekeeping was satisfactory.
Component Verification Based on the Probabilistic Risk Assessment The inspectors checked vario>is valve alignments and support systems within the auxiliary feedwater, charging system, and component cooling water. The review was based on the licensee's probabilistic risk assessment of the dominant contributors to core melt. -The inspector verified the configuration of the following risk-significant components on several occasions during the report period. The associated systems and component positions are listed below.
Auxiliary Feedwater System Emergency Feed Valve-(FW-MOV-35)
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Feedwater Bypass Valves (FW-HIC-301-1,-2,-3,-4)
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Discharge Cross-Connect Valve (FW-MOV-160)
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Steam Supply and Bypass Valves to the Terry Turbines (MS-V-1305, MS-V-1574A, MS-V-1574B)
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Component Cooling Water System Reactor Coolant Pump Oil Cooler and Thermal Barrier Containment isolation Valves
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(CC-V-901, CC-V-728)
Charging System
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Reactor Coolant Pump Seal Water Return and Bypass Valve (CH-TV-240/241, CH-Vi 345A,B,C,D)
The inspectors determined the system and component configurations were satisfactory.
2.2 Follow-up of Events Occurring During Inspection Period During the inspection period, the inspectors provided on-site coverage and follow-up of unplanned events, Plant conditions, alignment of safety systems, and licensee actions were reviewed. During event follow-up, the inspectors reviewed the corresponding plant information report (PIR) package, including the event details, root cause analysis, and corrective actions taken to prevent recurrence.
2.2.1 Auxiliary Feedwater Pump Water IInmmer On November 3,1992, CYAPCo performed monthly surveillance test SUR 5.1-13A, " Auxiliary Feed Pump (P-32-1 A) Function Test." While in the process of restoring-the system line-up as described in step 6.2.8 of SUR 5.1-13A, a water hammer occurred. The step requires that the
'A' auxiliary feed pump (AFP) discharge valve (FW-V-183) be opened and locked. When the
operator opened the valve, a pressure surge resulted in shaking of the pipe, pipe heat-up, and over-ranging of the pressure indicators on the suction piping. The pressure surge was from the -
main feedwater system. The main feedwater system was connected to-the auxiliary feed pump -
through two check valves which leaked by. Check valves FW CV-156-1,156-2,156-3, and
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156-4 had previously been found to be leaking by. Licensee actions to address this condition
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(detail 4.3). The second series check valve that leaked is FW-CV-184 located at the discharge-of the AFP. The licensee postulated that the failure of this valve to seat resulted-in the water hammer. CYAPCo entered the applicable technical specification for the 'A' AFP inoperability.
Upon identification, control room operators restarted the 'A' AFP. After completion of the operation of the 'A' AFP,. operators operated the 'B' AFP. After each subsequent operation, no discharge check valve backleakage or any pressure surges were noted. CYAPCo engineering and operations visually inspected accessible sections of the 'A' AFP suction line. The iiispection reviewed the physical condition of the pipe, pipe supports and welds, and any signs of system
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leakage. No abnormal conditions were noted. The licensee restored the 'A' AFP system back to an operable status.
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- The inspector discussed the event with control room operators and CYAPCo engineering personnel. The inspector questioned whether the suction piping and supports had exceeded acceptable stress limits beyond what could be surmised from a visual inspectica. At the end of the insp2ction period, CYAPCc was evaluating the postulated stresses to the suction piping. T'le inspector concluded that the preliminary acceptance of system operability was appropriate based on the visual examination results. No repairs to the d;scharge check valve (FW-CV-184) were performed. The inspector considers this item open pendir.g review of the suction pressure stress calculations (IFl 50-213/92-20-01).
2.3 Procedure for Responding to Natural Disasters The inspector reviewed the CY procedure for responding to natural disaster, AOP 3.2-5,
Natural Disasters," Revision 11 dated September 9,1992. This review was a part of a larger review of emergency and abnormal operating procedures for Haddam Neck. Procedure step 4.4.2.a.2 lists Woodward-Clyde Consultants in New Jersey as a contact to obtain information by telephone on the intensity of a seismic event following indications of an earthquake. The inspector contacted Woodward-Clyde on November 5, and was informed by a company representative that seismic information was no longer available at that location, since the seismic group had moved to Las Vegas over a year ago. The information in AOP 3.2-5 for two other sources of seismic data was found to be current.
The matter was discussed with the Operations Manager, who took the information for action. The licensee will review the status of the contract for seismic information with his consultant, and change the procedure accordingly. The licensee also intends to assure that other telephone-contacts referenced in operating procedures r cuvent. The inspector noted that, aside from this minor discrepancy, the AOP was of very good quality. The inspector had no further comments at this time. The qui.ity of Haddam Neck procedures are routinely reviewed during resident inspections.
3.0 RADIOLOGICAL CONTROLS (71707)
During routine inspections of the accessible plant areas, the inspectors observed the implementa-tion of selected portions of the licensee's radiological controls program. The inspectors reviewed utilization and compliance with radiation work permits '(RWPs) to ensure that detailed descriptions of radiological conditions were provided and-that personnel adhered to RWP
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requirements. The inspectors observed controls of access to various radiologically controlled areas and the use of personnel monitors and frisking methods upon exit from thost aw The inspectors also noted posting and control of radiation areas, contaminated areas ann' hot spots, and labelling and control of containers holding radioactive materials were in accordance with licensee procedures. The inspector determined that the health physics technician control and monitoring of these activities were goo _. _ _ _.. _.___. _ _ _ _._ _ _ _, _. _ _ _ _ _ _ _ _
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L 3.1 General Emplo3ee Training The inspector observed the conduct of the general employee training given on October 19, 1992,
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to contractor and licensee employees as part of the program for station access and annual refresher training. The topics observed included general plant orientation and information, plant
security, industrial safety, emergency plan actions, and radiological protection and practices.
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The training included instructor lectures, video tape presentations, and a practical exercise in r
radiological protection practices. The information presented described the health problems and
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risks attendant with the exposure to radioactive materials, and.was appropriate to satisfy the requirements of 10 CFR 19.12 and Regulatory Guide 8.13. The inspector found the lectures, presentations, and exams were comprehensive, accurate, and of excellent quality.
The presentations encouraged student discussions, and program changes and additions were also r
discussed.
The training also covered the employee nuclear safety concerns (NSCP) and the fitness for duty
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(FFD) programs. Iloth programs were covered in sufficient detail to provide the worker with needed information on program function and accessibility. The supervisor's responsibilities under 10 CFR Part 26 and the FFD manual were described in detail. The presentations on the NSCP included a review of the options available to workers to address concerns, as weii as the worker's rights to discuss contuns without retribution. The training covered recent changes to the NSCP, including the elimination of the safety concern function formerly provided by the Nuclear Review Team. The inspector verified the training sr Jon conformed with the licensee's September 25, 1992, letter to NRC Region I, as one of sevnal actions taken to enhance the effectiveness of the NSCP.
4.0 M AINTENANCE AND SUltVEll.1,ANCE (61'J26,62703 wd 71707)
4,1 Maintennnee Observation The inspectors observed various corrective and preventive maintenance activities for compliance with procedures, plant technical specifications, and applicable codes and standards.
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inspectors also verified appropriate quality services division (QSD) indvement, use of safety i
tags, equipment alignment and use of jumpers, radiological and fire prevention centrols,
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personnel qualifications, and post-maintenance testing. Portions of activities that were reviewed included:
Corrective Maintenance, 'll' Service Waler Adams Filter llackwash Pump
On November 9, the inspector observed portions of the troubleshooting activities under authorized work order (AWO) 92-11096.- The inspector independently verified the adequacy of the equipment tagging order; no discrepancies were noted.
The inspector pointed out that the work order referenced procedures PMP 9,5-99, Maintenance
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of 480 volt motors," and PMP 9.5-157, "480 volt Insulation Test," whereas the backwash motor
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subject to the maintenance activity was a 120 voh ac motor, The supervisor made the
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appropriate corrections to the work order. Overall, the work activity observed was satisfactory.
CY-92-10554, ' A' Diesel Generator Instrument Air Filler
The inJine Olter in the auxiliary air supply for the 'A' diesel generator (liDG) failed on
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October 21, allowing a continuous air now out of the Olter blowdown outlet. The condition was discovered by an auxiliary operator during routine rounds. Immediate actions were taken to limit the air Dow through the filter while maintaining suf0cient air pressure to components supplied by the auxiliary air system. Diesel operability was not affected.
The inspector reviewed work activities in progress on October 22 to repair filter FI 128-1 A under AWO 92-10554. Licensee examinations determined that the float assembly was not the cause of the failure. The Coat assembly was intact and showed no signs of gross deterioration or fragmentation. An imperfection in the seating surface for the blowdown outlet valves was noted. Ilowever, the valve still leaked after the imperfection was removed by maintenance personnel. The Olter was replaced with a spare unit from plant stores. The inspector reviewed the Oller installation after completion of the repairs and noted the piping and valve configuration was proper and the Olter was functioning properly.
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Plant engineering performed a root cause evaluation of the failed unit. The inspector examined the Olter internals along with plant personnel responsible for evaluation of potential llalstron filter defects per Pilt 92-182. This examination confirmed that the 00at assembly was not in a deteriorated condition as described in the vendor Part 21 information letter (see section 7.4
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l below). The failure was due to service related wear in the sealing surface of the piston that controlled air Dow to the blowdown outlet valve. The automatic blowdown feature is not needed for this application, since the air line is also equipped with an air dryer. As a long-term corrective action, the licensee is considering replacing the llaistron units with filters having a simpler design.
The inspector had no further questions regarding the identification and resolution of the problem.
The inspector noted that the personnel involved with the maintenance activity showed a high regard for administrative controls, and, in particular, for assuring that the work activity accurately re0ccted the intended work scope documented in the AWO.
l CY-92-10055, 'll' Auxiliary Feeduater Pump Iluses
CY-9210090, 'A' Auxilinry Feedunter Pump lloses
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l The inspector reviewed licensee activities in October 6 - 7, to address degraded hydraulic hoses
l used to actuate the steam admission valves for both auxiliary feedwater (aFW) pumps. The i
repair activities were completed under the above work orders and related AWOs CY-92-10091 l'
and CY-92-10089. CYAPCo identined that the hydraulic hoses internal to the hydraulic pump skid were incompatible with the operating fluid used to run the actuator on the steam admission valve. This material incompatibility caused the discharge hose for the AC hydraidic pump (P-
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and on the 'A' AFW system (1-.nps P-179-1 A & 2A). The stainless steel replacement hoses were designed and installed under Replacement item livaluation (Rlli) PEG CY-Oli4)028, which included engineering and seismic evaluations for the modified hoses. All hosn were replaced and both AFW systems were satisfactory tested per SUR 5.7-87 on October 7.
Inspector review of the maintenance activities in pr, ass identified no inadequacies related to compliance with the work conttol documents, in meeting Technical specification requirements for plant ojeration with degraded AFW systems, and with the quality of the completed work.
The inspector determined the failure root cause investigation and the technical evaluations
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accompanying Rlli PliG CY Oli4)028 were acceptable. Post repair equipment restoration and AFW system lineups were also reviewed and found to be satisfactory. The engineering support for this problem are discussed further in Section 6.2 below.
4.2 Suncillance Obsenation The inspectors witnessed selected surveillance tests to determine whether: frequency and action statement requirements were satisfied; necessary equipment tagging was performed; test instrumentation was in calibration and properly used; testing was performed by qualified personnel; and test results satisned aceptance criteria or were properly dispositioned. Portions of activities associated with the following procedures were observed:
I)iesel Generator Room Air Flow Test
The inspectar reviewed actions under AWO CY-92-10547 on October 27, to test emergency diesel generator !!DG 2il following modifications to the room intake duct. NRC Insp:etion
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Reports 92-12 and 92-15 describe previous NRC review of CYAPCO actions to address diesel room air flow. The diesel room doors have been kept open to assure adequate air flow through the room. During this inspection period, the licensee installed a weather curtain in the intake tunnel under bypass jumper 92-49 to minimize the heat loss from the room while the diesels are in a standby condition. The inspector reviewed the licensee's technical evaluation for the by pass jumper and the results of the air flow test. The liccusee plans to install a similar curtain in tne
' A' liDG room pending acceptance of the 9' modifications.
The licensee established 40 degrees Fahrenheit (F) as the temperature limit in the diesel rooms to assure that the fast start times are not adversely impacted. Temperatures in the m.ms have been measured in the range of 75 to SO degrees with the outside temperature as low as 32 degrees F so far this season. The licensee plans to install a permanent backdraft damper in the intake tunnels in March 1993. The weather curtain was di signed to reduce the amount of heat loss from the room while minimizing the resistance to air flow. The curtain is made from a silicone rubber impregnated fiberglass fabric cut into 1 foot strips. Several strips of material were mounted sequentially across the top of the intake tunnel and hang vertically to close off the intake opening under static air flow conditions. The inspector reviewed the as-built installation under
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dynamic flow conditions on October 27 and noted the curtain was securely fastened to the
concrete wall of the tunnel.
Data for the October 27 test was taken in accordance with procedure VP-651, " Diesel Generator lluilding Air Intake Flow Measurement." The test method was to collect air flow data in the i
diesel room using a hand-held anemometer while the diesel was running and the room ventilation
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fan was operated in fast speed. The measured air flow rate was 38,915 cubic feet per minute
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(CFM), which was well in ucess of the 36,(R) cfm required to assure diesel operability. The
'B' EDG was returned to an operable status on October 27 after acceptance of the test data and
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upon completion of routine operability testing to satisfy the requirements of Technical Specification 4.8.1.1.1.2. The inspector determined licensee actions to address this matter were satisfactory.
Emergency llus Undervolinge Reiny Testing
The inspector reviewed test procedures used to ve.ify the proper operation of the undervoltage relays provided on 4160 volt emergency buses 8 and 9. The purpose of the review was to verify that Technical Specification 4.3.2.1. (Table 4.3-2) requirements regarding the surveillance of.
engineered safety features actuation instrumentation were satisfied. The results for the most recently completed test were also reviewed, as follows:
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SUR 5.8-1, "Ilus 8 Level 1, Level 2, and Level 3 Undervoltage Calibration Surveillance," performed October 29, 1991.
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SUR 5.8-2, "llus 9 Level 1, Level 2, and Level 3 Undervoltage Calibration Surveillance," performed I)ccember 11,1991.
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SUR 5.8 3, "4160 Volt Bus 8 Level 1,2, and 3 Trip Actuating Device Operational Surveillance " performed October 29,1992.
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SUR 5.8-4, "4160 Volt Bus 9 Level 1,2, and 3 Trip Actuating Device Operational Surveillance," performed December 11,1991.
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SUR 5.5-34, " Emergency llus 8 Level 1,2, and 3 Undervoltage Protection System Trip Actuating Device Operational Test," performed October 2,-1992.
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SUR 5.5-35, " Emergency Bus 9 Level 1,2, and_3 Undervoltage Protection L
System Trip Actuating Device Operational Test," performed October 2,1992.
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The inspector verified that the procedures provide a proper test of the undervoltage sensing channels,. including a test of the undervoltage relays and the channel ac:uation and failure annunciators. The trip actuating device operational tests are performed per SUR 5.5-34 and 35,
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which initiates a signal t.t the sensing device for each undervoltage channel and verifies the L
operation of the associated alarm relays. A complete test of the actuation logic is performed per
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SUlt 5.8-3 and 4 on a refueling outage basis. The above tests, taken in conjunction with the te.
of the safeguards actuation trains with a partial loss of AC (SUlt 5.1-18 and 19, " Test of Train
' A' (10 Safety inspection Actuation Signal (SlAS) with a Partial 1.oss of AC") provide for a complete test of the actuation logic, from the sensor down to the end point devices operated by the logie. The inspector concluded that, taken together and in overlap, the tests provide a proper test of the actuation channel logic. The results for the most recent tests completed were satisfactory.
liased on the above, the inspector verified the requirements of Technical Specification 4.3.2.1 are satisfied by the CYAPCo test program.
SUll 5.1-104 A, Iturie Acid th path Operability Test
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The inspector observed the performance of SUR 5.1-104A on November 3.
The weekly surveillance was performed to implement technical specification surveillance requirements 4.1.2.2.a. and 4.1.2.2.b. The inspector determined the surveillance was performed acceptably with good adherence to the procedure by the auxiliary operator.
The inspector questioned an outstanding trouble report on differential pressure transmitter P1)l-114 for the turic acid filter. The transmitter readings are recorded during performance of the surveillance. The readings are used to determine when to replace the boric acid tiller. The transmitter failed to respond during boric acid pump operation. The trouble report had been issued in August 1990. The inspector reviewed past maintenance activities on PI)l-119. Since early 1985, the licensee has identified improper response of the differential pressure gauge (e.g.,
AWO 85-01177). The gauge failed due to boric acid precipitation within the sensing lines. The normal boric acid concentration is greater than 14,000 parts per million (PPM) requiring the line to be heated to greater than 140 degrees I; The sensing lines for the differential preuure transmitter are not heat traced.
When operable, the differential pressure instrument is used to monitor the condition of the bonc acid filter. The lack of this information affects the operator's ability to detect tiller degradation that could reduce the flow of borie acid to the charging pumps. The minimum Dowrate assumed in the design basis is greater than or equal to thirty gallons per minute (Gl'M). This Dowrate ensures that the reactor can be made suberitical from all operating conditions, and that postulated accident transients are controlled. The boric acid flow path is required to be operable pursuant to Technical Specification 3.1.2.2. The operators indirectly assess the condition of the filter weekly by the performance of SUlt 5.1-104A and during quarterly flow measurements. The weekly surveillance adjusts a flow restrictor bypass valve and measures the corresponding decrease in horie acid pump pressure. SUlt 5.7-183, "in-service Testing of A and 11 lloric Acid Pumps," verifies flowrate is greater than eighty GPM on a quarterly basis. The inspector rev!:wed the surveillance data since August 1990 and determined that minimum flow requirements were consistently attained.
The inspector reviewed the maintenance history for the boric acid filter and determined that the elements had been previously replaced due to degradation. Corrective action included plant modification PDCR 90 098, "lloric Acid Filter Material Ciiange," that replaced the elements in
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June 1990. No maintenance problems have resulted from a clogged filter. CYAPCo actions to address a long-standing maintenance item on the boric acid sensing lines were not timely; however, the boric acid system safety function was not compromised a.id alternative methods to assess filter conditions were effective.
At the close of the inspection, CYAPCo engineering was preparing a plant modification to add heat trace circuits to the PDl-119 instrument lines. The circuit is to be supplied from the existing heat trace circuit. The inspector questioned CYAPCo whether any other instruments are subject to boric acid precipitation during operation. CYAPCo stated that PDl 119 is the only instrument affected. Routine NRC inspections of plant operations will include a review of the boration system flow paths, including the operability of associated instrumentation.
SUlt 5.1-13A, Ausillary Feed Pump (P-32-I A) Functionni Test
On October 6, the inspector observed the performance of SUR 5.1-13A.
The inspector determined the surveillance was performed satisfactorily and noted good adherence to the procedure. The inspector also noted good coordination between operations personnel and the in-service test personnel which minimized the time safety equipment was out of service due to the surveillance.
5.0 EMERGENCY PREPAREDNESS (71707)
5.1 Qunrterly Emergency Plan Mini Drill The inspector observed the conduct of a quarterly mini-drill by CY APCo personnel on November 5, 1992. The fourth quarter drill was conducted in conjunction mth -the liaddam Neck simulator, and resulted in the partial activation of the onsite emergency response facilities. The corporate emergency organization did not participate.
The emergency scenario simulated a total loss of feedwater to the steam generators, followed by a break in the reactor coolant system boundary and the loss of primary containment. The-scenario was designed to result in the declaration of a Site-Area emergency. A drill objective was to demonstrate strategies to rapidly deploy repair teams. The NRC resident inspectors and the NRR Project Manager observed the conduct of the drill from the control room annex, the emergency operations facility, and from inside the plant.
g The licensee concluded that the drill objectives were met. No discrepancies were identified by the NRC inspectors. The licensee's emergency preparedness is reviewed as part of the NRC's routine inspection program for if addam-Neck.
6.0 ENGINEERING AND TECilNICAL SUPPORT (71707)
i The inspectors reviewed selected engineering activities. Particular attention was given to safety evaluations, PORC approval of modifications, procedural controls, and post-modification testing.
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Two noteworthy nulineation packages were initiated during the inspection period. The first modi 0 cation was PDCR 1294, " Modification to Provide an Automatic Open Signal to the Service Water Adams Filter." The modincation climinated the need for local (at the MCC) operator action to open the motor-operated valves (SW MOV-837A and -83711), The new design provides an automatic opening of the valves for an engineered safety actuation signal. The inspectors determined the modiGeation was appropriately implemented and post-modi 5 cation testing was well controlled. The inspectors noted the operators were aware of the associated emergency operating procedure changes.
The second modiGeation, PDCR 12271, " Condensate Storage Tank," constructed a 100,000 gallon non-safety grade tank. The purpose of the modification was to climinate several failure mechanisms that could deplete the inventory of the safety-grade Demineralized Water Storage Tank. The modification was on going during the inspection period. The inspector noted good coordination between the construction and the plant operating staffs.
6.1 Thennal Stresses in Piping Connected to the Reactur Coolant System Puroose
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During this inspection period, the licensee entered containment to acquire temperature data for certain piping interconnected with the reactor coolant system (RCS). The data acquisition and
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evaluation were in response to NRC Ilulletin 88-08, " Thermal Stresses in Piping Connected to Reactor Coolant Systems " The bulletin and its three supplements required the licensee to identify unisolable lines from the RCS. Once selected, the licensee was to evaluate and/or monitor the lines to detect thermal cycling resulting from valve leakage and thermal stratification. The
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purpose of the inspection was to review licensee actions to meet the commitments to the bulletin.
Jhek['rowld The NRC had previously reviewed the adequacy of the systems selected in response to NRC -
11ulletin 88-08. The licensee committed to other actions in response to the bulletin, including temperature monitoring of unisolable sections of the charging system (charging fill and auxiliary spray), and non-destructive examination (NDB) of selected pipe welds. The welds selected for examination were in the fill header line, high pressure safety injection, and residual heat removal systems. NDE measurements were completed during the 1989 refueling outage with acceptable results. lly letter dated September 25,1992, the NRC concluded that the licensee program met the intentions of the bulletin.
f Periodic temperature monitoring is a method to provide assurance that potential valve leakage
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.does not result in adverse trends in thermal stresses, liraided thermocouples were installed under Plant Design Change Evaluation CYS9 92, " Charging Loop Fill Temperature Monitoring " The
thermocouples were fastened to the outside surface of the unisolable section of the pipe and measure the pipe wall temperature. CY APCO acquires temperature data at these locations during routine containment entries.
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in 1991, CYAPCo initiated an independent assessment of the program by Structural integrity Associates, Inc. The licensee's contractor provided recommendations to improve the program.
The recommendations included changes to the monitoring location and the need to establish continuous monitoring. The previous monitoring location (approximately two inches from the charging fill header motor operated valves) was moved downstream closer to the RCS, The reason for the change was to eliminate anomalous data from pipe conduction near the isolation valve. The inspector concluded that CYAPCo implemented the vendor's recommendations.
Plant Design Change Record (PDCR) 1196, " Additional Charging System Temperature Indication," incorporated the recommendations. Pipe temperatures were recorded in April 1992 and October 1992 using procedure IING 1.7-113. " Charging Fill Header Temperature
Monitoring." Temperature data was taken over 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> at 30 minute intervals. Thermal
stratification and isolation valve leakage were monitored using top and bottom pipe temperatures.
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The temperature data indicates that no thermal cycling is presentt however, varying degrees of
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stratification and valve leakage were detected in the charging system fill headers.
No stratification or leak-by was detected in the auxiliary spray system. The licensee noted that the loop one fill header temperatures had warmer pipe wall temperatures on the bottom of the line.
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While unexpected and not explained, the condition is not considered signi0 cant and does not in itself result in adverse pipe stresses.
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The inspector questioned the licensee on the degree of stratification and acceptability of the results relative to piping thermal stress limits. The licensee concluded that the leakage from the isolated section of the charging system into the reacter coolant system was small enough not to affect reactor coolant system leakage calculations or chemical volume control system operation.
The inspector conGrmed this conclusion by noting no increases have occurred in reactor coolant system unidentified leakage calculations.
The NUSCO engineering organi7ation provided the inspector the preliminary piping stress calculations based on the current temperature data. The calculations showed that a margin exists -
to the allowable stress for the worst case condition (i.e., total stress of 31,662 PSIA vs. an allowable stress of 41,160 PSI A).
In summary, the inspector determined the licensee has ful0lled his commitments to NRC llulletin 88-08. The preliminary engineering evaluations concluded that the pipe stresses caused by leakage into the unisolated piping were acceptable, No plausible reasons exist for the loop one fill header top temperature to be cooler than the bottom pipe temperature. Licensee actions to address the fill header MOV leak-by, and the temperature inversion in loop one fill header are still under evaluation.
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6.2 Ausillary Fredwater (AFW) Pump Ilydraulle lloses The steam driven auxiliary feedwater pumps (P-32-A&ll) have steam admission valves (MS-PICV 1206A & !!) with hydraulic actuators. The actuators are operated by skid mounted hydraulic pumps mounted in enclosures located outside of the APW pump rooms. The hydraulic skid for each AFW pump has a DC and an AC operated pump to supply fluid to the actuators.
The DC pump for each system is considered to be safety related, is kept in standby during normal operation, and will automatically start on low pressure. The non safety related AC hydraulic pump normally operates to maintain hydraulic fluid pressure to the actuator.
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The AC pump for the 'IP AFW system was removed from service on October 6 when it was noted that the AC hydraulic oil pump was running but not pumping Guld as evidenced by low operating entrent on the motor. Prior to disassembly of the pump, the licensee suspected that either the pump coupling had failed or that the pump suction inside the sump had clogged. The -
'IP AFW system remained operable since the DC oil pump was in service to maintain pressure to the actuator.
Since the AFW system was deemed operable but degraded with the DC pump in operation, plant personnel proceeded on a repair plan to investigate the AC oil pump. The 'IP AFW pump was removed from service at 10:18 p.m. on October 6 and the plant entered a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> action statement to allow removal of the AC pump for inspection. Licensee examinations of the disassembled AC pump noted the coupling and suction were satisfactory, but that a bypass hose on the discharge of the pump had deteriorated, allowing the pump discharge flow to be short circuited back to the sump 'servoir. Further investigation concluded that the hose material was incompatible with the hydratdc operating Guld in the presence of air._This was evidenced by the-observation that the hose had deteriorated from the omside in, at the location along its length
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corresponding to the normal level of Guid in the sump.
The identification that the hydraulic Guid and hoses were incompatible was significant, since the hydraulie skids were new systems installed under PDCR 91-1127 and placed into service in the
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Spring of 1992.
Further immediate licensee investigation concluded that the same hose configuration and material existed for the DC hydraulic pump in the 'lP AFW system, and for the AC and DC pumps on the 'A' AFW system. Ilased on the above finding, the licensee concluded that both AFW systems were. inoperable on the basis that a conunon mode failure mechanism existed. The plant entered TS action statement 3.7.1.2 at 11:15 p.m. on October 6 which allowed for continued plant operation with both AFW systems inoperable for up to 24 -
hours.
Licensee action included the following: (i) replacement of the failed hose in the 'IP-AFW AC-hydraulic pump; _ (ii) an engineering evahiation of the root cause of the failure; (iii) an engineering evaluation of the remaining hoses and polymer based components to determine what
- other components in the AFW hydraulic system may be susceptible to degradation and to correct this condition as necessary; and (iv) inspection and replacement of similar hoses to eliminate any
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other degraded conditions.
As noted above, the hose degraded because its material was incompatible with the operating fluid. The hose was manufactured by Goodyear and consists of a nitrile core covered by neoprene rubber. The wo king fluid is lloughto-Safe 620, which is a glycol / water working liquid CYAPCo further noted that lloughto Safe 620 was in use on the gas turbine generator (GTG) at Millstone 1. The licensee determined that the GTG operability was not affected because the pump hoses were not immersed in the fluid in that application.
The licensee determined that the hoses internal to the hydraulle sump failed because they t.cre immersed in the working Huid which attacked the cover material in the presence of air. The Goodyear hoses on the hydraulic skid were provided by a vendor (Woodward) as part of his scope of supply for the hydraulic actuators. When contacted in October 1992, Goodyear
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confirmed that use of its hoses in a glycol environment on its exterior surface is not acceptable.
Hydraulic hoses are also installed between the pump skids and the valve actuators; these hoses were within the licensee's scope of supply as part of the AFW system PDCR The external-hoses are manufactured by Aeroquip and are designed for water / glycol fluid service. The nitrile core is compatible with the glycol fluid. The external hoses only see the working fluid on the inside and are not subject to the degradation observed on the internal hoses. The licensee concluded that no other polymer based components in the AFW hydraulic system were degraded.
As discussed in Section 4.1 above, the hoses internal to the sump were replaced with stainless steel tubes which are compatible with the hydraulic fluid. Completion of this action allowed the plant to exit the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> action statement at 4:44 pm on October 7.
The incompatible combination of hose material and hydraulic fluid constituted an unacceptable design for the modified AFW system. The inspector's review focused on how this condition occurred, and whether the engineering reviews in support of PDCR 91-1127 carlier in 1992 should reasonably have precluded the combination. The inspector reviewed the design change package (Drawing DSR-CY-S 698-92) and noted that the pump skid, reservoir, and contained hoses were listed on the Bill of Material as within the vendor's scope of supply. Plans to use a glycol based hydraulic fluid were originated in 1991 in order to minimize the fire loading for the AFW system.-. This action was planned when the valve actuators for both trains were to be hicated in the AFW building. In eatly 1992, the modification plans were changed to relocate the hydraulic skids into separate enclosures outside of the AFW building. This was done to address common mode failure concerns from postulated high energy line breaks of piping inside the AFW building. Although the relocated components lessened the need for glycol based fluid, when the equipment vendor (Woodward) for the hydraulic skid was contacted, the licensee determined that, in the vendor's opinion, the fluid was compatible with the material used in the -
hoses supplied with on the pump skid.
Licensee actions were in progress at the conclusion of the inspection to investigate this issue under Plant Information Report 92-178. Destructive examination of the failed hose was planned to confirm the materials of construction. Based on a pressure test to 2000 psig and a normal hydraulic operating pressure ofless than 1000 psig, the licensee subsequently determined that the hoses on the other (non-failed) hydraulic pumps were degraded, but capable of performing their intended functions at the time of discovery. Regardless of the status of the hydraulic actuators,
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both Al:W trains remained available to the operators for reactor decay heat removal through manual operation of the steam admission valves. This issue is under evaluation for reportability under 10 CFR Part 21. The results of the licensee's investigation for plR 92178 will be reviewed on a subsequent NitC inspection (IFl 50-213/92-20-02).
In summary, the inspector determined plant personnel displayed an excellent safety perspective by declaring both AFW systems out of service based on the potential for a common mode failure mechanism. This action was later demonstrated to be conservative based on engineering evaluations which showed that the hydraulic skids were capable of performing their intended design function. The actions by the plant staff were prompt and aggressive during this period to resolve the operability issue, to repair the defective hose, and to address the root cause of the degradation.
The licensee's preliminary investigations concluded that the incompatible combination of hydraulic Guid and hose material was the result of reliance on the equipment vendor who supplied the hoses with pump skid, and who consented to the use of a glycol based hydraulic f'uid. The inspector concluded that while a more rigorous licensee engineering analysis may have detected this incompatible combination, it is not reasonable to expect that the review for the design change package would detect this discrepancy in the face of the vendor's expertise and recommendations. Accordingly, the engineering support for the 1992 design change was acceptable.
7.0 SAFETY ASSESSMENT AND QUAL.lTY VEltlFICATION (40500,71707,90712, nud 92701)
7.1 Plant Operations lleview Committee The inspectors attended several l'! ant Operations Review Committee (PORC) meetings and verified member attendance satisfied Technical Specification 6.5 requirements. The meeting l
agendas included procedural changes, proposed changes to the Technical Specifications, Plant l
Design Change Records, and minutes from previous meetings.
PORC meetings were l
characterited by frank discussions and questioning of the proposed changes. In particular, consideration was given to assure clarity and consistency among procedures, items for which l
adequate review time was not available were postponed to allow committee members time for l
further review and comment.
Dissenting opinions were encouraged and resolved to the satisfaction of the committee prior to approval. The review on October 7 regarding the operability of auxiliary feedwater system following replacement of degraded hydraulie hoses was thorough and probing, and displayed a strong safety ethic. The committee closely monitored and evaluated plant performance and conducted a thorough self-assessment of plant activities and programs. The inspectors concluded the PORC was effective.
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7.2 Operntional Experience Feedback Prognun l
l}cekground
A previous NRC inspection (report 50-213/92-04) identified a concern regarding the licensee's surveillance testing of the emergency diesel generators. The NRC found that the licensee's review of information Notice (IN) 91-13, " inadequate Testing of Emergency Diesel Generators,"
was inadequate in that the engineering review of the issue was too narrow in scope.
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Additionally, as described in inspection report 50-213/92 08, the NRC concluded that the licensee response to IN 87-40, "I ackseating Valves Routinely to Prevent Packing Leakage " was protracted and delayed, and failed to prevent the event described in licensee event report 91-021.
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In light of the above events, the inspector initiated a review of CYAPCo's action = to address
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industry events as described in NRC ins to determine the effectiveness of the operating-experience feedback program. The inspector selected approximately five percent of the NRC ins issued between 1987 through 1989, for review, as listed in Attachment 1.
Administrative Program
CYAPCo action for ins in 1987-1989 was initiated by the Northeast Utilities Services Company (NUSCo) Nuclear Operations Department (NOD) in 1987-1989. For each IN, the NOD set up
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objectives, assigned a nuclear operation assignment (NOA), developed a priority for review, and l
c:.tablished a due date for the response. The operating facility (CYAPCo) would receive the FOA and initiate an assignment based on management's sdection of the most knowledgeable individual. The IN follow-up would be a collateral function for the assigned individual. The response was approved at the site director level and returned to the NOD department. -The NOD personnel would review the operating facility response for adequacy and consistency, and initiate closure.
The inspector found that each IN reviewed had an associated NOA tracking number. The
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closure of the NOA generally occurred in less than six months from issuance of the IN. The
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inspector noted that, for approximately 50 percent of the NOAs, the NOD provided additional direction for review of the topic beyond the information within the IN. Approximately 10 percent of the licensee actions to address IN issues resulted in the development or a change to an existing program / procedure. For example, the program to non-destructively examine the reactor vessel thimble tubes was upgraded significantly. Also, various engineering evaluations were performed in response to NRC ins. The topics evaluated included factory sizing of air operated valves,
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acceptance limits of wall thinning for thimble tubes, loss of air study for safety-related valves, and voltage drop calculations for the 125 volt direct current (DC) system.
The inspector concluded that the administrative process to receive and assign review responsibili-ty for _ industry experiences promulgated by NRC ins, and to track these assignments to
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completion was satisfactory and thorough. The NOA assignments often result in a change to a program or procedure, which presumably would be beneficial to preclude an operational event.
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Under the present process, there is nothing that highlights the rea >n that a change was made in response to an NOA, such that the corrective action is preserved from inadvertent deletion by -
a subsequent change in the program or procedure. The inspector noted that the present admini-strative process could be improved by the inclusion of a provision that would preserve actions resulting from NOA assignments.
hegiallLEffcclinnci5 The inspector evaluated the effectiveness of the licensee's actions for ins by looking for correlations between the IN issues and operational events. The database reviewed for recent operational events was the plant information reports (PIRs) issued between 1990 1991. Except _
for the issue described further below, the inspector did not identify any specific correlations
>etween NRC ins, licensee actions in response to ins, and recent operational events as documented in the PIRs. There is evidence that very good work was done to address some_
issues. In particular, the licensee's actions were prompt and very extensive in response to ins 88-92, 89-71, 89-44, 87-13, and 87-39. Further, for some Notices, the licensee had programs to address the issues already in place.
The inspector conchided that the CYAPCo response to NRC IN 88-37, " Flow Illockage of Cooling Water to Safety System Components," did not prevent the occurrence of an operational event. The notice was issued on June 17, 1988, to alert licensees that stagnant cooling water o
lines are subject to flow bk)ckage. CYAPCo referred to its previous review of IN 86-96, " Heat Exchanger Fouling Can Cause inadequate Operability of Service Water Systems," and concluded that the issue had been appropriately addressed. No further action was deemed necessary in response to IN 88-37. CYAPCo's actions for IN 86-96 considered four service water heat exchangers (residual heat removal, containment air recirculation,' emergency diesel generator, and component cooling water), and included measures to detect flow blockage to each cooler.
CYAPCo subsequently issued PlR 91-141 on August 2,1991, to address plugging in the service water supply to a normally isolated, redundant spent fuel pool heat exchanger (SFP liX). The corrective actions for the PIR event included the development of administrative control procedure (ACP) 1.2-10.5, " Service Water Monitoring," to monitor heat exchangers witl stagnant lines.
The inspector concluded that had the licensee given more consideration to the information in IN 88-37, controls might have been developed to prevent blocking the SFP llX stagnant lines. The inspector determined that the corrective actions regarding the associated PIR were appropriate.
GlarhlSion Overall, the inspector determined the operational experience program was acceptable and generally effective for the-period reviewed. Program changes and engineering evaluations developed in response to ins appropriately addressed issues applicable to 11addam. Neck. All
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ins were assigned NOAs and the licensee has a good system to assure timely closure of NOAs.
There is evidence that very good work was done to address IN issues. Ilowever, this review identined one event in 1991 that might have been avoided had the response to IN 87-37 been broader in scope. Taken together with the EDO and valve issue discussed above, the inspector
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noted that three operat!onal events in 1991 might have been precluded by more timely or
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thorough reviews of industry issues. Whether these remain as isolated events, or are indicative of a weakness in the depth of engineering review provided for Notices, is a matter that requires further NRC review and evaluation. This matter will be the subject of further NRC assessment in followup of IN issued in the 1990 - 1992 period. This matter is considered open pending completion of that review (IFl 50-213/92-20-03).
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7.3 Follow-up of Previous Inspection Findings The inspectors reviewed licensee actions taken in response to open items and f'.idings from previous inspections. The inspectors determined if corrective actions were appropriate and thorough and whether previous concerns were resolved, items were closed where the inspector determined that corrective actions would prevent recurrence. Those items for which additional licensee action was warranted remain open. The following items were reviewed:
7.3.1 (Closed) IFISO-213/92-15-04: ESAS Undervoltage Trip Scheme This item was open pending NRC review of the licensee's program to test the trip logic for the engineered safety features undervoltage trip devices and actuating logic, This topic was reviewed during this inspection, as described in Section 4.2 above. The inspector conclund that, taken together and in overlap, the CYAPCo test method provides a proper test of the actuation channel logic and that the requirements of Technical Specification 4.3.2.1 are satis 0ed. This item is closed.
7.3.2 (Closed) U11100-213/91-12-01: Pressurizer Level Technical Specification This item concerned the variation ofinterpretations of Technical Specification Limiting Condition for Operation (LOC) 3.4.3.a between operating and staff crews during the dynamic simulator portion of the operator requalification examination given in June 1991. A June 21,1992, memorandum to all licensed operators stressed a need for literalinterpretation of ali LCOs under the revised Technical Specifications. The training staff included the requaliGcation examination scenario and the June 21,1991, memo in a training quiz that was administered to and discussed with all licensed operators, Based on the corrective actions completed, this item is considered closed.
7.3.3 (Open) Ulti 50 213/92-14-02: Electrical llousekeeping Practices During initial inspection of this issue, the NRC determined that electrical boxes within the cable vault were missing fasteners. One electrical box (no. 5) was inspected in detail and determined to contain safety-related channels. The item was unresolved pending CYApCO's determination of the design, installation, and separation requirements for electrical box no, 5 and remains open pending completion of this effort and further NRC review.
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As part of this item, CYAPCo committed to initiate generic corrective actions to address missing fasteners on electrical boxes. CYAPCo's quality services department initiated trouble reports for electrical box deficiencies in nine distinct areas of the facility. The inspector reviewed the work activities, and completed a walkdown of the areas requiring corrective maintenance. The inspector noted that all identified deficiencies had been corrected. The licensee's actions to identify and correct other deficiencies were thorough.
7.4 Ileslew of Part 21 Notification - Air Filters The inspector reviewed the licensee's response to a potential deficiency identified in a 10 CFit Part 21 noti 0 cation provided in a letter from MKW Power Systems to the NitC staff. The problem was initially reviewed in Inspection iteport 92-18 and was documented in plant information repott 92-182 on October 8.
The issue involved a defective air filter assembly, Balston P/N A9131)X, that contained a
" float" assembly that was found to deteriorate and break into pieces, and thereby jeopardve the diesel air start system. CYAPCo's initial review on September 25 concluded that the suspect tillers were not installed in F.DG-2A or 2B air start system. Unlike the design described in the notice, the CY diesel air tanks do not have an automatic blowdown system, but require a manual action to clear any accumulated water in the lines. The starting air system does not use a filter with the " float" assembly that was found to deteriorate.
CYAPCo identified on October 8 that the components were installed in the diesel instrument air system as filters FL-128-1 A and 18. One filter is used in each instrument air system between the main air receivers and the air dryer assemblies. The instrument air system nrovides a regulated air supply to the following diesel components: air-operated (AOV) supply valve from the underground storage tank to the diesel day tank (a normally locked open valve); the storage tank level indicator; and the AOV for the service water supply to the diesel heat exchangers. The licensee's failure mode effects evaluation performed on October 8 determined that a failed 00at assembly would not affect the operability of the fuel and cooling water supply lines. A plugged level sensor would fail the indication down scale and would thus be detectable.
Based on the above, no immediate diesel operability concern was identified and CYAPCo referred the issue to site engineering for further evaluation and to develop action plan. The plan I
included an inspection of the installed filters at the first opportunity the diesel was removed from service. The inspector reviewed the diesel auxiliary air piping on October 8, which ine!uded a
" hands-on" <. rification of the piping configuration and associated components. The inspector identified no inadequacies with the licensee's operability or failure mode conclusions.
On October 21, filter FL-128-1 A failed allowing a continuous air flow out of the blowdown line.
The filter was repaired under AWO 92-10554, as described in Section 4.1 above. Licensee examinations during the repair activity determined that the float assembly was not the cause of the failure. Further, the float assembly was very much intact and functional, and showed no signs l
of gross deterioration or fragmentation as was reported to occur at another facility. Based on the l
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inspection results for the 'A' filter and in consideration of the similar service time for both filters, the licensee concluded it was not necessary to inspect the internals of filter Fiel28-lli at-this time. However, due to some wear evident in the Goat, and in light of the industry experiences, the licensee plans to replace the filters in the Spring of 1993. The licensee is considering replacing the existing filters with one of a simpler design, because the automatic condensation-blowdown feature of the llalston units is not needed in the CY application.
Maintenance and modification of onsite emergency power supplies are routinely reviewed during resident inspection of plant activities.
The inspector determined licensee actions in response to the Part 21 notification and to review a potential component degradation at CY were acceptable. Site engineering support was effective -
to achieve a timely and proper resolution of the issue.
8.0 EXIT MEETINGS During this inspection, periodic meetings were held with station management to discuss inspection observations and findings. An exit meeting was held November 14,1992, to summarize the conclusions of the inspection. No written material was given to the licensee and no proprietary information related to this inspection was identified.
The following inspection was also conducted by Region I based inspectors during this report period, inspection Reporting Areas Reoort No.
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Inspector Inspected
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_ October 5-9,1992 L. Prividy MOV Inspection
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ATTACllM ENT I 1.ist of NitC Infonnation Notices (ins) Itesiewed i
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.l fM7 IN Notice 87-44, ' ihimble Tube Thinning in Westinghouse Itcactors," dated 9/16/87 IN Notice 87-13, "l'e:,cntial liigh 1(adiation 1 ields/ Inadvertent 1 oss of Water from Spent I ue!
Iwl," dated 2/24/87 IN Notice 87 39, " Control of Ilot l' article Contamination At Nuclear l'ower I'lant," (hted 8/21/87 IN Notice 87-67, "1 cssons 1.carned from llegional Inspections of l_icensee Actions in itesponse to Ilill 80-11," dated 12/31/87 1988 l
IN Notice 8S-51, "l:ailures of h1ain Ste.un Isolation Valves," dated 7/21/SS IN Notiec SS-73, "l)irect-1)ependent i eak Characteristics of Containment Purge Vahes," dated 9/8/8S
,
IN Notice 88-37, "l low lilockage of Cooling Water to Safety System Components,"
I dated 6/17/88 l
IN Notice 88-20, "l!nauthori/ed Individuals hianipulating Controls in Control lloom Activities,"
dated 5/5/8S IN Notice S8-92, " Potential for Spent I:uel l'ool 1)raindown," dated ll/22/SS l
IN Notice 88-43, " Solenoid Valve l>roblems," dated 6/23/8S IN Notice 88-94, "l'otentially Undersized Vahe Actuators," dated 12/1/8S M85!
l
'
1N Notice 89 7l, "l)iversion of Itllit Seal Cooling Water lilow I)aring liceirculation Operation l'ollowing a I.OCA"
. _ _ _ _ _
.
a NITACilSIENT I (cont.)
IN Notice 89-91, "Inadetpiate Control of Temporary Modifications to Safety-l(elated Systems,"
dated 12/6/89 IN Notice 89-26, " Instrumentation Air Supply to Safety-l(elated I!quipment," dated 3/7/89 IN Notice 89-32, " Surveillance Testing of !!!'OP Systems," dated 3/23/89
,
IN Notice 89-01, " Valve ikxty litosion," dated 1/4/89 i
l IN Notice 89-86, "T ~ ilk Circuit lireakers Missing Closing Latch Anti-Schock Spring," dated
'
l 12/15/89 i
i IN Notice 89-57, " Unqualified lilectrical Splices in Vendor-Supplied liliQ liquipment," dated 7/26/89 IN Notice 89-16, "theessive Voltage 1) rop in 1)C Systems," dated 2/16/89 i
l l
IN Notice 89-41, " Operator 1(esponse to Pressurization of Low Pressure Interface Systems,"
l dated 4/20/89
l
,
.