IR 05000395/1993024
| ML20059K837 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 10/27/1993 |
| From: | Cantrell F, Thomas Farnholtz, Haag R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML20059K819 | List: |
| References | |
| 50-395-93-24, NUDOCS 9311160212 | |
| Download: ML20059K837 (15) | |
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UMITED STATES -
/e Pro \\
NUCLEAR REGULATORY COMMISSION
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E 101 MARIETTA STREET, N.W.. SUITE 2900 7.
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ATLANTA, GEORGIA 303234199 a.,
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Report No.:
50-395/93-24 Licensee:
South Carolina Electric & Gas Company Columbia, SC 29218 Docket No.: 50-395 License No.: NPF-12 Facility Name: Virgil C. Summer Nuclear Station Inspection Conducted:
September 4 through October 13, 1993 Inspectors: h YYYd lo/22./9S R. C. Haag, Senior Resident Inspector Date Signed
@ IN M
10 / 24 /9 3 T. R. Farnholtz, Residgnt Inspector Date Signed Approved by:
/g/2-/[9j FToyd S/ Cantrell, Chief
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Dat# Sighed Projects Section IB Division of Reactor Projects SUMMARY Scope:
This routine inspection was conducted by the resident inspectors onsite in the areas of monthly surveillance observations, monthly mainten'ance observations, operational safety verification, installation and testing of modifications, r M ew of nonconformance reports, and action on previous inspection findings.
Selected tours were conducted on backshif t or weekends. These tours were conducted on six occasions.
Results:
No violations or deviations were identified.
The carbon steel cooling water piping for the service water pump motor bearing coolers is continuing to experience degradation. The licensee discovered the
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piping for "A" pump clogged (paragraph 4).
The controls implemented for the usage of temporary leak sealants appeared to be adequate (paragraph 4). An inspector followup item was identified for continuing problems with the chill water system chillers (paragraph 5). A proactive modification was implemented to improve valve position status lights in the control room, but the initiative to improve similar applications was not completed (paragraph 6).
The licensee's review of a 10 CFR Part 21 report on pump runout conditions for ESF pump was thorough. Also the investigation, identification, and reporting of a 10 CFR Part 21 defect on deteriorated parts of safety-related relays was thorough and of sufficient detail (paragraph 7).
9311160212 931027 PDR ADOCK 05000395 O
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REPORT DETAILS
1.
Persons Contacted Licensee Employees W. Baehr, Manager, Health Physics C. Bowman, Manager, Maintenance Services
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M. Browne, Manager, Design Engineering
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- M. Fowlkes, Manager, Nuclear Licensing & Operating Experience
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S. Furstenberg, Associate Manager, Operations
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- S. Hunt, Manager, Quality Systems
- A. Koon, Nuclear Operations Project Coordinator
- D. Lavigne, General Manager, Nuclear Safety-J. Nesbitt, Acting Manager, Technical Services K. Nett.es, General Manager, Station Support
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H. O'Quinn, Manager, Nuclear Protection Services i
- M. Quinton, General Manager,-Engineering Services
J. Skolds, Vice President, Nuclear Operations
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- G. Taylor, General Manager, Nuclear Plant Operations
- R. Waselus, Manager, System Engineering
- R. White, Nuclear Coordinator, South Carolina Public Service Authority
- B. Williams, Manager, Operations
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Other licensee employees contacted included engineers, technicians, operators, mechanics, security force members, and office personnel.
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- Attended exit interview
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Acronyms and initialisms used throughout this report are listed in the last paragraph.
2.
Plant Status
The plant operated at approximately 98 percent' power throughout the
inspection period.
Power had been reduced from 100 percent to 98
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percent on August 7,1993, due to level oscillations in
"A" steam l
generator.
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Other inspections or meetings:
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Floyd Cantrell, Section Chief, DRP, was onsite September 16 and l
17, 1993, to review resident inspectors activities, tour the plant-
and meet with licensee management.
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Luis Reyes, Deputy Regional Administrator, was onsite t
October 12, 1993, to meet with the resident inspectors, tour the j
plant, and meet with licensee management.
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3.
Monthly Surveillance Observation (61726)
l The inspectors observed surveillance activities of safety-related j
systems and components listed below to ascertain that these activities
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were conducted in accordance with license requirements. The inspectors
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verified that required administrative approvals were obtained prior to
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initiating the test, testing was accomplished by qualified personnel in l
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accordance with an approved test procedure, test instrumentation was
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calibrated, and limiting conditions for operation were met. Upon completion of the test, the inspectors verified that test results conformed with technical specifications and procedure requirements, any
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deficiencies identified during the testing were properly r_eviewed and resolved and the systems were properly returned to service.
Specifically, the inspectors witnessed / reviewed portions of the
following test activities:
a.
Operational test of emergency diesel generator "A" (STP 125.002).
This surveillance satisfied the requirements of TS 4.8.1.1.2.a.
The inspector observed preparations for engine start, clearing the cylinders of possible moisture, and monitoring the engine following the start and subsequent electrical loading. The inspector noted good coordination between the control room and the operator at the diesel. The engine started, obtained full speed, and carried full load as required.
b.
Reactor core flux mapping (STP 212.001). A full core flux map was obtained using the movable incore detectors. To obtain the required data from symmetric thimbles normally served by detector
"D", which was inoperable, detector "C" was used in the emergency mode. The inspector noted a good level of knowledge on the part of the person performing the surveillance.
c.
Operational test of chill water pump
"C" (STP 229.001).
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d.
Quarterly engineered safety feature (ESF), Train "B", slave relay testing (STP 105.015). The majority of the slave relay tests are accomplished by actuating individual slave relays and verifying that the actuation devices, i.e., valve, pump, etc., change to their ESF positioh. Due to the sensitivity of "B" RCP seal leakage to operating changes in seal injection or CVCS letdown, the licensee altered the method for testing two valves. Train
"B" charging containment isolation valve, XVG8108, was tested by removing the thermal overload and verifying, at the motor control center, that the close start contact actuated for the valve's Limitorque operator.
For the letdown containment isolation valve, XVG8152, the test verified that the slave relay output contact in
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the circuit for closing the valve actually changed state by a i
change of voltage in the circuit. The inspector reviewed the TS definition for slave relay testing and concluded that the
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licensee's testing methodology was acceptable.
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e.
Monthly verification that emergency core cooling system piping'is full of water (STP 105.006). This task was accomplished by
verifying flow into a poly bottle at six high point vents in the t
RHR pumps discharge piping.
f.
Operational test of containment high range area radiation monitor
RMG-18 (STP 360.008).
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All the observed tests were performed in accordance with procedural
'a requirements and demonstrated acceptable results.
4.
Monthly Maintenance Observation (62703)
Station maintenance activities for the safety-related systems and
components listed below were observed to ascertain that they were conducted in accordance with approved procedures, regulatory guides,
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and industry codes or standards.
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i The following items were considered during this review:
that limiting
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conditions for operation were met while components or systems were removed from service, approvals were obtained prior to initiating the-
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work, activities were accomplished using approved procedures and were inspected as applicable, functional testing and/or calibrations were
performed prior to returning components or systems to service,
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activities were accomplished by qualified personnel, parts and
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materials used were properly certified, and radiological and fire
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prevention controls were implemented. Work requests were reviewed to j
determine the status of outstanding jobs and to ensure that priority
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was assigned to safety-related equipment maintenance that may affect system performance.
The following maintenance activities were i
observed:
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a.
Inspection of component cooling water booster pump XPP0058C (PMTS P0168791). The inspector witnessed the disassembly of the pump and
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the inspection of internal components. Good housekeeping practices
were demonstrated.
b.
Preventive maintenance to functionally test the instrument air-system (PMTS P0169548).
This semi-annual activity involved individual five minute blowdowns to 85 psig air pressure at 66 I
drains / low points in the system.
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c.
Lubrication of the tendon gallery sump pumps XPP0060A and B (PMTS P0169605 and P0169606).
During a tour of the tendon gallery the j
inspector made the following observations:
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A wall in the access to the gallery was wet, with water flowing i
down the wall. The electrical conduit and junction boxes
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mounted to the wall were also wet. The water appeared to be i
coming from ground water inleakage.
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An electrical extension cord was tied off into the sump.
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The water piping used to fill the cathodic protection wells was
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leaking into two wells causing the water to overflow onto the I
fl oor.
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While some of the tendon covers were leaking small amounts of
grease, there were no large grease leaks that could adversely
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affect the tendons.
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A small amount of fumes / steam was exiting one.of the cathodic i
protection wells that penetrate the base mat for the reactor building liner protection. After reviewing this condition, the licensee stated that higher than normal current for this well i
caused the water to heat up and produce a small amount of steam. The circuit for that well was later de-energized. The licensee is in the process of deleting cathodic protection for
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the reactor building liner, therefore they decided not to pursue this item any further.
NRR has been asked to review the
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need for cathodic protection of the reactor building liner.
These observations were conveyed to the licensee for review and any I
resulting corrective actions.
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d.
Corrective and preventive maintenance on "B" emergency diesel generator.
The work observed included repair of air leaks at two
strainers and a coupling in the air start system (MWRs 93N3026,
93N3027, 93N3029), replacement of the rocker arm lube oil filters (PMTS P0168856), repair of a sticking check valve, XVC31628, in the -
l service water line to the air compressor after cooler (MWR 93N3187)
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and inspection of the elements in the air inlet filters (PMTS P0169324). All the observed work was performed per the applicable work instructions and the mechanics had a good working knowledge of their assigned task.
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e.
Repair of cooling water flow indicator, IFI4405, for
"A" service water (SW) pump lower motor bearing (MWR 9303898). The gauge was initially reported as not working due to the indication reading full scale. After the gauge was replaced, the flow indication went to zero.
The licensee discovered that a portion of piping was
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was replaced.
Based on the bearing temperature plots prior to the
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repair activity, the licensee believes that the bearing cooler had
been receiving cooling water flow. The temperature plots showed
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that "A" and "B" SV pump motor bearing temperatures trended
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consistently at a normal temperature band. The licensee theorized
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that while the pump was secured for the indicator work, the piping t
became clogged.
While the temperature plots indicated that this condition did not adversely effect previous pump performance, the inspector was
concerned that cooling water piping had become clogged which could prevent a SW pump from performing it's safety-related function.
The licensee has experienced many problems with the carbon steel
piping that supplies SW to the bearing coolers. The majority of l
the problems have dealt with pin hole leaks in the piping.
Microbiological induced corrosion (MIC) and general corrosion of
the pipe have initiated these leaks. During previous piping repairs the inspectors have noted a large buildup of corrosion
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products on the inside of the old pipe.
The licensee's policy has been to correct the leaks as they occur. Other than reviews and
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studies by the licensee for complete replacement of the piping, the inspector is not aware of any current efforts to resolve the
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l problems of leaks or clogs in the existing cooling water piping.
The licensee informed the inspector that the maintenance practices for the existing carbon steel cooling piping would be reviewed to determine if additional work is warranted prior to replacement of the piping.
The licensee is currently reviewing the different replacement options and has not established any schedule for the piping replacement. The RIs will follow the licensee's plans to correct the corrosion problem.
An inspection on the usage of temporary leak sealants was performed. Temporary leak sealants are used mainly on non safety-related applications. The inspector was aware of two examples where temporary leak sealants were used on safety-related
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I equipment. They included steam leaks on a S/G secondary manway and -
on a steam trap isolation valve upstream of a mainsteam isolation valve.
The process involves pressure injection of a fluid type material into the area of leakage and allowing the material to harden and stop the seal leak. All the previous temporary leak repairs have been performed by contract personnel using the contractor's procedures.
For a safety-related uses of temporary leak sealants, engineering approval and evaluation is required as part of the NCN disposition.
The licensee stated that an NCN must be written for any safety-related application.
Non safety-related applications are performed.
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using the guideline of "non-standard" repairs in SAP-300, Conduct of Maintenance. The maintenance manager must provide prior
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approval for all non-standard repairs. The licensee tracks the permanent repairs of these leaks by keeping the NCN or MWR open until the final repair is completed.
The licensee's goal is to permanently repair these leaks during the next refueling outage.
For a few items such as heat exchangers, the licensee has decided-it is economically beneficial to allow the temporary leak repair setup to remain in place.
For the majority of temporary leak repairs that the inspectors have observed, the permanent repairs were completed in subsequent outages.
Licensee oversight of these activities is generally provided by
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engineering through the NCN process and by maintenance during the
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interface with the contractors.
Quality Assurance performs an
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initial review of contractor procedures and qualifications for i
safety-related applications.
For non safety-related uses,
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maintenance does a nonformal review of contractor procedures. With
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the exception of the S/G manway leak that could not be sealed, the
licensee has been successful with temporary leak repair while not adversely effecting component / system operation. During the i
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inspector's review of this subject, no inappropriate usage of
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temporary leak sealants was noted.
l The maintenance activities observed were well executed.
Several i
minor material condition deficiencies were noted in the tendon
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gallery. The clogging of a cooling line for a SW pump motor bearing indicates that continuing problems are occurring with_the carbon steel piping and that additional actions may be required i
before the piping is replaced.
5.
Operational Safety Verification (71707)
a.
Plant Tour and Observations The inspectors conducted daily inspections in the following areas:
control room staffing, access, and operator behavior; operator adherence to approved procedures, TS, and limiting conditions for operations; and review of control room operator logs, operating orders, plant deviation reports, tagout logs, and tags on components to verify compliance with approved procedures.
The inspectors conducted weekly inspections for the operability verification of selected ESF systems by valve alignment, breaker positions, condition of equipment or component (s), and operability of instrumentation and support items essential to system actuation or performance. The service water system and the safety-related portion of the mainsteam system were included in these inspections.
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i Plant tours included observation of general plant / equipment l
conditions, fire protection and preventative measures, control of i
activities in progress, radiation protection controls, physical
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security controls, plant housekeepirg conditions / cleanliness, and
missile hazards.
Reactor coolant system leak rates were reviewed i
to ensure that detected or suspected leakage from the system was
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recorded, investigated, and evaluated; and that appropriate actions
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were taken if required. Selected tours were conducted on i
backshifts or weekends.
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b.
Problems with the Chill Water (VU) System Chillers l
The licensae has continue to experience problems with the VU
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chillers.
In addition to the air conditioning of l
safety-related areas, the VU system also supplies cooling water for the charging / safety injection pumps and the CCW pump motor which adds to the importance of the VU system.
The inspector reviewed the following chiller problems:
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On September 28, 1993, it was noted that the oil in the lower
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sight glass on "B" chiller dropped from 1/2 to 1/8 level in the previous 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The chiller had been idle for eight days.
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The chiller was declared inoperable when the operator questioned if the chiller would start with the low oil level.
Since the other two chillers were operating satisfactory, no TS
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LC0 was entered. Oil was later added and the chiller was started. The lowtring of oil level in the upper sump has been a longstanding problem.
If a chiller is idle for a lengthy time period, oil will leak from the upper sump to the lower sump. Once the chiller is. started, the oil reclaim system will replenish the level in the upper sump. A concern exists that if the level is too low in the upper sump then the auxiliary oil pump, which takes a suction from the upper sump, may not develop adequate oil pressure to clear the interlock when starting the chiller. The source of the oil leakage from the upper to lower sump is not fully understood.
The inspector reviewed licensee engineering documentation dating back to 1988 which discussed this problem and recommended corrective action to prevent recurrence. The
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with the emphasis to reduce lengthy time periods for an idle chiller. The licensee believes that one of the main factors j
for this condition not having a significant impact on chiller i
operation deals with the slow lowering of oil level and the H
ability to monitor level each shift during operator rounds.
The operator's log specifies that the lower sight glass should l
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be full and a MWR initiated when the oil level;gets to 7/8'
full. The inspector noted that the-sight glasses for
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t chiller have a discoloration on the inside surface which made inspection of oil level difficult.
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On September 20, 1993, the duplex lubricating oil filter for
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"C" chiller was swapped due to a high differential pressure
(DP) across one of the filters. On the following day, the DP i
for the other filter was also high. The chiller was shutdown
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and both filter elements were replaced. ' During conversation
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with maintenance personnel, the inspector was informed that "C" chiller in the past has had dirtier oil than the other two
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chillers and required more frequent filter replacements. All
the chillers have the lubricating oil replaced annually. An i
engineering write-up on the chillers mentioned that
"C" chiller
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has a darker color in the sight glass which may indicate a past
problem of extensive rust within the chiller. One of the r
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engineering recommendations was to develop a procedure to operate the non safety-related cleanup system on "C" chiller.
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The licensee informed the inspector that these~ issues and the
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chiller maintenance would be reviewed to determine if.
additional action is needed.
Based on the length of time these
issues have existed, the inspector was concerned that adequate
resources were not applied to resolve these problems.
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followed by the inspector. This matter is identified as IFI i
395/93-24-01, longstanding chiller problems.
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6.
Installation and Testing of Modification (37828)
Two minor modifications were reviewed as part of the ongoing evaluation
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of plant modification activities.
Included in the review were direct
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observation of portions of the installations, post-modification testing and review of the MPJ ;)ackages.
MRF 21632 and acconpanying MCNs implement human factor upgrades in the
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control room and oa local plant 9anels. MCN B revised the limit switch
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wiring for the SW isolation val /es associated with the EDGs in order to
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improve the logic of the valves' status lights on the MCB. The
original status lights consisted of a single set of red and green
lights for both the inlet and outlet valves, XVB3104 and XVB3121.
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During a SW system reviu in 1988, ISEG identified th:it the red and green status lights provided little useful information. The logic was set up such that the red (open) light was on if either valve were fully
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open or throttled and the green (closed) was on unless both valves were
fully open.
Since the valve alignment was for the inlet valve to be l
fully open and the outlet to be throttled, both the green and red
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lights were normally lit. The ISEG concern was that one of the valves.
could be fully closed and both lights would still be lit.
ISEG recommended that engineering review this and similar valve position lights for human factors improvements. MCN B changes the coloring of the indicating lights and upgraded the logic.
If the inlet valve is.
full open and the outlet valve is either full open or throttled, a blue light is lit.
If the inlet is not full open or if the outlet is closed, then an amber light is lit. The inspector observed portions'of the wiring change and verified that the post modification testing was performed for the various valve configurations. Also, the inspector reviewed the drawings in the control room which were affected.by the MCN and verified that the correct " hold" and "in-process" stamps were on the applicable drawing.
The MCN provided only limited instructions (approximately one half page) for accomplishing the modification.
The only directions given for changing the logic was to rework the wiring as shown on the attached diagrams and schedules. The inspector observed the electrician and the supervisor reviewing the wiring diagrams and later conferring with the system and design engineers-to verify their understanding of wiring changes. Additional instructions would have clarified the actual work required to complete the modification. The.
inspector noted that the post modification testing instructions were more detailed in specifying the required actions for verifying the status lights worked properly.
While the inspector recognized that.this improvement modification resulted from a licensee initiated system review, the ov m il scope of the modification was questioned. After reviewing the MPF and discussions with design engineering, the inspector notea that action to improve the status light logic for similar application, i e., SW to the-chillers and to the CCW heat exchangers had not been initiated. This condition existed despite the recommendation in 1958 by ISEG to modify the SW to EDG valve status lights and similar applications. Design engineering has subsequently reviewed the MCB valve status light logic and initiated action to modify the status lights that were similar to EDG SW valves.
MRF 21073 dealt with the removal of the service water screen wash pumps XPP0043 A, B, and C.
These pumps take a suction on the discharge side of the respective service water pump and direct a spray of water onto the traveling screen.
This is to prevent the buildup of foreign material on the screen which could result in clogging and subsequent loss of suction of the service water pump. Operating experience and testing has shown that sufficient discharge pressure is developed by the service water pumps to perform this function without the additional pressure from the screen wash pumps. The inspector observed the removal of the "C" service water screen wash pump, the preparations for'
welding in the new section of piping for the "C" screen wash system,
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these observations.
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7.
Review of Nonconformance Reports (71707)
NCNs and Part 21s were reviewed to verify the' following:
TS were complied with, corrective actions as identified in the reports were-
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accomplished or (fing pursued for completion, generic items were identified and reported, and items were reported as required by the TS.
a.
On July 15, 1993, Westinghouse notified the licensee of a potential i
safety issue pursuant to 10 CFR 21.21. The issue dealt with a
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potential plant configuration that would result in unacceptable-pump runout flows for a charging / safety injection pump.
In a post i
large break loss of coolant accident (LOCA) scenario, with a loss of Train "A" as a single active failure, the combination of one i
charging pump left running and multiple flow paths due to the
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alignment to hot leg recirculation through the charging system can
result in a potentially unacceptable runout condition. The
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transfer from cold leg to hot leg recirculation requires that
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several valves be repositioned.
If Train "A" power were not.
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available then some valves could not be repositioned due to a. loss
of their normal power supply. Operator action to locally open or
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close these valves may not be possible due to the potential that
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valves would be in a high radiation area. The inability to close i
one valve would establish the multiple flow paths for the remaining t
charging pump.
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On September 10, 1993, another utility notified the NRC that they.
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were vulnerable to an unacceptable runout condition for a charging pump during the scenario discussed in the preceding paragraph. The
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inspector reviewed the licensee's emergency operating procedures (E0Ps) and their response to the Westinghouse notification. The licensee had determined that the E0Ps contained actions to
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prevent / mitigate these conditions. The licensee had previously
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identified this vulnerability to a loss of Train A power and revised the E0Ps to reposition these two critical valves during an
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earlier time frame in the accident response. At that point if i
Train A power is not available, the E0Ps contain instructions to
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provide alternate means for repositioning the valves. After
reviewing E0Ps and additional information, the inspector concluded
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that the E0Ps adequately addressed this potential safety issue.
b.
On September 17, 1993, the licensee notified the NRC of f
10 CFR Part 21 defect involving Model D26 Type M relays
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manufactured by Cutler-Hammer.
In March, 1993, while inspecting
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two spare relays drawn from the warehouse, the contact holders (made of a polycarbonate material, Lexan), were found to be l
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deteriorated.
It is believed that the damaged contact holders have the potential to jam in place or crumble such that fragments would
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I prevent adjacent contacts from changing state. Similar Cutler-
l Hammer relays are utilized in a variety;of plant applications. A
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I rev.ew of maintenance history records revealed that related
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problems with Cutler-Hammer have not occurred.
The two relays with the defective contact holder had been supplied I
by Vitro Corporation, who had also supplied the ESF. load
i sequencers.
Relays that had been supplied by other vendors were
l inspected and no signs of deterioration were observed. The i
licensee believes that the packaging of the Vitro. supplied relay
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was the cause of the degraded part. Approximately 40 spare Cutler Hammer relays were supplied and packaged by Vitro on 1979 and 1983
t purchase orders, in air tight mylar / foil bags. These bags were not opened until the relays were ready for installation.
It is
believed that ammonia generated by the phenolic resin relay housing l
material reacted with contact holder material and causing it to
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crystallize and embrittle. After testing relays supplied by Vitro
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and other relays not in air tight bags, an independent laboratory l
concluded that this was the cause of the degraded part. The
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laboratory stated the following conditions were necessary for i
degradation of the Lexan contact holders:
(1) An enclosed space i
which will prohibit diffusion of the ammonia, (2) Safficient
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temperature for generation of the ammonia and (3) Sufficient time
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for the attach of the Lexan by the ammonia.
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Standard packaging of these relays, as supplied by Cutler-Hammer, I
does not include airtight bags. This was confirmed by a review of other Cutler-Hammer relays in the licensee's warehouse. Normally Vitro supplies Potter-Brumfeld relays which are believed not to utilize Lexan material. The licensee specified Cutler-Hammer i
relays on the purchase order since they are used in various applications in the plant.
i Three relays supplied by Vitro had been installed in the plant.
Two of the relays were subsequently replaced as part of the followup work associated with this issue. The one remaining relay is in a non safety-related application and is scheduled for repl acement. The licensee's evaluation stated that a failure of I
the installed relay to operate has no safety significance. After l
reviewing the application, the inspector agreed with this l
conclusion. An inspection by the licensee of-other Cutler-Hammer l
relays installed in the plant revealed no signs of similar degradation.
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8.
Action on Previous Inspection Findings (92701, 92702)
(Closed)
Inspector followup Item 92-07-01, Control of VCT dilution during reactor startup The system alignment required by REP 107.003, Beginning of Cycle Dilution to Criticality, allowed the VCT to be filled with diluted water during the approach to criticality. The inspector was concerned that once the dilution was stopped during the reactor startup the-additional diluted water-in the VCT would enter the RCS and possibly over dilute the RCS. Step 3.14 had cautioned that the VCT would become filled with diluted water and after termination of reactor makeup water RCS dilution may continue for approximately 45 minutes. However,-no guidance was provided to prevent the over dilution or ensure reactivity control was maintained. A change to REP 107.003 was issued prior to the last refueling outage startup to bypass the VCT during the dilution
process which allowed borated water to remain in the VCT.
The inspector reviewed the change to REP 107.003 and verified that the system alignment prevented dilution of the VCT.
(Closed) Violation 395/92-10-01, Unknowingly rendering plant equipment inoperable due to an inadequate procedure and failure to follow procedural requirements.
This violation had two examples. The first example involved a radiation monitor becoming inoperable following a maintenance activity,-
because the applicable procedure provided no guidance for adjustment of.
the radiation monitor setpoints. The inspector verified that Health j
Physics Procedure HPP-904, Use of the Radiation Monitoring System, was i
revised to specify the particular group that has responsibility for i
making setpoint adjustments for the individual radiation monitors.
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Also the involved groups, i.e., operations, I&C, and health physics.
received training on lessons learned from this event.
The second example involved disabling the degrade voltage protection for a Class IE bus when a power supply fuse for a relay was removed.
The licensee had indications that the relay was not operating properly, therefore, they decided to pull the power supply fuse with the belief that the relay would fail to it's safe / actuation position. The licensee's research failed to recognize that this new style relay fails to the non-conservative position when power is removed.
The electrical elementary drawings for the relays were revised to clearly indicate the relay contact logic when control power is removed.
Operations personnel received training on this subject. The licensee also plans to upgrade these relays to provide a visible indication on the availability of control power.
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(Closed) Violation 395/92-10-02, Failure to Review a Vendor Technical i
Manual Contributed to a Reactor Trip and LER 92-03.
_1 During replacement of.a power supply in a nuclear instrumentation
'I drawer, a short circuit of the cabinet power source occurred and
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resulted in a reactor trip.
The applicable technical manual _ was not-l used for the power supply replacement activity which contributed to the i
unintentional short circuit.
In addition, the generic troubleshooting l
procedure that was used provided littlt guidance for this activity.
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In response te this event, the licensee initiated several corrective I
action items. The importance of using/ referring to vendor manuals was
emphasized to I&: personnel. A new procedure, for developing i
troubleshooting and repairs plans to be used for non-routine l
activities, was issued. The inspectors have noted extensive use of
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troubleshooting plans for maintenance activities which are not covered l
by existing instructions.
In addition, individual troubleshooting and i
repair procedures were developed for critical components.
Initially 24 l
component applications were identified for these procedures, with
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additional procedures being developed as other applications are
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identified. The inspector observed a power supply replacement in a y
solid state protection system cabinet and noted that the procedure l
provided complete information for replacement of the power. supply.
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9.
Exit Interview (30703)
The inspection scope and findings were summarized on October 14, 1993, j
with those persons indicated in paragraph 1.
The inspectors described l
the areas inspected and discussed the inspection findings.
No dissenting comments were received from the licensee. The licensee
did not identify as proprietary any of the materials provided to or i
reviewed by the inspectors during the inspection,
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Item Number Description and Reference 395/93-24-01 IFI - Longstanding chiller problems
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(paragraph 5b).
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l 10.
Acronyms and Initialisms
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CCW Component Cooling Water CVCS Charging and Volume Control System
DP Differential Pressure
I EDG Emergency Diesel Generator
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E0P Emergency Operating Procedure ESF Engineered Safety Feature
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HPP Health Physics Procedure
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I&C Instrumentation and Control j
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IFI
_ Inspector Followup Item ISEG Independent Safety Evaluation Group LCO Limiting Conditions for Operations LER Licensee Event Report LOCA Loss Of Coolant Accident MCB Main Control Board
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MCI Microbiological Induced Corrosion MCN Modification Change Notice MRF Modification Request Form HWR Maintenance Work Request NCN Nonconformance Notice NRC Nuclear Regulatory Commission NRR Nuclear Reactor Regulation PMTS Preventive Maintenance Task Sheet PSIG Pounds Per Square Inch Gauge RCS Reactor Coolant System REP Reactor Engineering Procedure RHR Residual Heat Removal RMG Radiation Monitor Gas RWP Radiation Work Permit SAP Station Administrative Procedure S/G Steam Generator SPR Special Report STP Surveillance Test Procedure SW Service Water TS Technical Specification VCT Volume Control Tank VU Chill Water