ML20137E949
ML20137E949 | |
Person / Time | |
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Site: | Oyster Creek |
Issue date: | 03/21/1997 |
From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
To: | |
Shared Package | |
ML20137E937 | List: |
References | |
50-219-97-01, 50-219-97-1, NUDOCS 9703280327 | |
Download: ML20137E949 (32) | |
See also: IR 05000219/1997001
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U. S. NUCLEAR REGULATORY COMMISSION l
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Report No. 97-01 i
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j Docket No. 50-219 ;
- 72-1004
, License No. DPR-16
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- Licensee
- GPU Nuclear incorporated ,
- 1 Upper Pond Road i
- Parsippany, New Jersey 07054 ;
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j Facility Name: Oyster Creek Nuclear Generating Station
Location: Forked River, New Jersey
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inspection Period: January 13,1997 - February 23,1997
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inspectors: Larry E. Briggs, Senior Resident inspector
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Stephen M. Pindale, Resident inspector
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l Approved By: Peter W. Eselgroth, Chief ;
j Projects Branch No. 7
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9703200327 970321
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PDR ADOC4 05000219
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EXECUTIVE SUMMAC','
Oyster Creek Nuclear Generating Station
Report No. 97-01
This integrated inspection included aspects of licensee operations, engineering,
maintenance, and plant support. The report covers about a six-week period of inspection.
P! ant Operations
- There were several weaknesses that resulted in a spill of about 250 gallons of water
from a control rod hydraulic control unit. The weaknesses included a poorly
prepared and untimely tagging request, the failure to use a print or diagram to verify
proper system status and configuration, and the lack of independent verification or
qualitative procedural acceptance criteria to verify that the tagging order was
correct (01.2),
e A recent move of one of the onshift senior reactor operators to an area from which
licensed operator and overall plant activities can be directly observed was a positive
initiative by operations management to enhance oversight and control of control
room activities (01.1).
- The operators and shift technical advisor were alert to identify and trend an
unexplained flow rate reduction for the "B" reactor recirculation pump (01.3).
e General Office Review Board (GORB) meeting sessions in the areas of operations
(status and significant events) and engineering were characterized by probin0
discussions. The GORB was constructively critical of station activities and was
focused on plant safety (07.1).
e Station management's efforts to communicate work performance expectations were
positive steps toward improving human performance (07.2).
Maintenance
- Routine maintenance and surveillance activities observed by the inspectors were
conducted safely and in accordance with station procedures (M1.3).
- The licensee approached the planning and execution of dilution pump maintenance
with a high level of safety. The installation of vibration monitoring sensors on the
No.1 pump was a positive first step to more actively monitor the performance of all
the dilution pumps (M1.4).
e Cable replacement activities for the "E" reactor recirculation pump motor-generator
set were completed without error. Personnel followed applicable instructions and
engineering provided strong support to maintenance personnel. Conduit re-routing
modifications were effectively implemented (M1.5).
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- The licensee had properly addressed the two f ailures of Limitorque motor operators
used in non-safety related applications. The licensee promptly verified that the
facility had not used any of the non-Limitorque supplied operators in any safety
application (M7.1).
- Maintenance personnel responde0 quickly and effectively to an occurrence in which
the augmented offgas system building became radioactively contaminated due to an
equipment failure (R1.2).
Enaineerina
- A large number of As-found Field Change Notices (FCN) had not received technical
review and approval indicating prior weak management of the engineering change
document process. The licensee's followup actions to their self-identification that a
significant number of FCNs did not receive the appropriate technical review and
approval were acceptable. No safety equipment deficiencies were identified in
connection with these findings. (E1.1)
- The licensee had provided appropriate attention to the outstanding issue of whether
relays for safety related applications were properly tested and monitored. A
communication weakness resulted in not testing allin-stock relays. The subsequent
conditional release for the installed relays was acceptable. Continued aggressive
followup is warranted to achieve full resolution of this issue (E1.2).
- The licensee did not display a conservative approach in deciding to increase the
amperage limits for the four remaining recirculation pump motor-generator (RPMG)
sets following the trip of the "E" reactor recirculation pump (cable failure), resulting
in an automatic trip of a second ("C") reactor recirculation pump. The licensee
observed a minor amperage oscillation while increasing RPMG set speed, and they
had recognized that an effective voltage regulator adjustment was not possible, -
particularly at higher RPMG set speeds. In addition, there have been prior and
repeated RPMG set operational problems, and these RPMG sets play an important
role in reactivity management. The resulting transient posed a challenge to control
room operators (E2.1).
- An August 1995 safety evaluation, performed to support a December 1995
modification to remove from service the isolation condenser (IC) radiation monitors,
was incomplete in that it did not recognize that the IC vent radiation monitors is a
NUREG 0737 requirement. This is another, although dated, example of failure to
conduct an adequate UFSAR review which the licensee is currently addressing
programmatically for future safety evaluations. This additional example indicates
the need to perform reviews of other previously completed safety evaluations to
determine whether other commitments or UFSAR items had been overlooked.
Additional information is necessary to determine whether the licensee is in
conformance with NUREG ltem 0737, and the issue is an unresolved item (E2.2).
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- The licensee aggressively pursued the root cause for failed temperature switches in
the main generator stator cooling system. They continued followup activities after
switches demonstrated a sensitivity to ternperature changes, and sent the defective
switches to an independent laboratory for further analysis. They also took prompt
and effective action to identify other switches in the plant that were of the same
type and have initiated action to replace them (E2.3).
e System engineering promptly responded and began collecting additional data
following an unexpected flow reduction in the "B" reactor recirculation pump flow
rate in an attempt to identify the problem. However, since a problem was not
identified, additional monitoring continued at the end of the inspection (01.3).
-* Engineering provided strong oversight and support of the "E" RPMG cable -
replacement activities, including the design and rerouting of a section of conduit
(M1.5). .
Plant Support
e The licensee effectively implemented the radiation protection and security programs I
(R 1.1),
o Radiation protection personnel promptly and appropriately responded to an event l
during which the augmented offgas building became radioactively contaminated due
to an equipment failure (R1.2).
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TABLE OF CONTENTS l
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EXEC UTIV E SU M MA RY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
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TA B LE O F C O NT ENT S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v j
l. OPERATIONS (71707, 93702, 40500) ............................... 1
01 Conduct of Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 !
01.1 General Comments ................................. 1 ,
O 1.2 Tagging Error on Control Rod Hydraulic Control Unit (Violation
9 7 -0 1 -0 1 ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
01.3 "B" Reactor Recirculation Pump Flow Fluctuations . . . . . . . . . . . 4
07 Quality Assurance in Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 t
07.1 General Office Review Board Periodic MeetMg . . . . . . . . . . . . . . 5
07.2 Employee Group Meetings ............................ 5 i
08 Miscellaneous Operations issues ................................. 6 .
08.1 Periodic Report Review .............................. 6 {
11. MAINTENANCE (61726, 62707, 90712, 92902) . . . . . . . . . . . . . . . . . . . . . . . . 6 !
M1 Conduct of Maintenance .................................. 6 l
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M 1.1 Maintenance Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 :
M 1.2 Surveillance Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 l
M1.3 Routine Maintenance and Surveillance Activities Conclusions ... 7 i
M1.4 Licensee Investigation of No.1 Dilution Pump Vibration ....... 7 l
M1.5 "E" Recirculation Pump Motor Generator Set Cable '
Re pla c e m e nt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
M7 Quality Assurance in Maintenance Activities . . . . . . . . . . . . . . . . . . . . 9
M7.1 Failure of Limitorque Valve Operator . . . . . . . . . . . . . . . . . . . . . 9
M8 Miscellaneous Maintenance issues .......................... 10
M8.1 (Closed) Licensee Event Report (LER) 96-13 . . . . . . . . . . . . . . . 10
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l lli. ENGINEERING (37551,40500,71707,92903) ........................ 11
El Conduct of Engineering .................................. 11
E1.1 As-Found Field Change Notice (FCN) Technical Review and
Approval Deficiencies .............................. 11
l E1.2 Followup and Evaluation for Safety-Related Relay Failures Due
to Manufacturing Defect (Unresolved item 97-01 -02) . . . . . . . . 12
l E2 Engineering Support of Facilities and Equipment . . . . . . . . . . . . . . . . . 14
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E2.1 "C" Recirculation Pump Motor Generator (RPMG) Set Trip . . . . . 14
E2.2 Isolation Condenser Vent Radiation Monitors Removed From
Service Prior to Addressing All Relevant UFSAR Commitments
(Unresolved item 9 7-01 -0 3 ) . . . . . . . . . . . . . . . . . . . . . . . . . . 16
E2.3 Update of Mercoid Temperature and Pressure Switch Failures . . 18
E8 Miscellaneous Engineering Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
i E8.1 (Closed) Unresolved item 50-219/9 5 24-01 . . . . . . . . . . . . . . . 20
E8.2 (Closed) Licensee Event Report (96-12) . . . . . . . . . . . . . . . . . . 20
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E8.3 (Closed) Licensee Event Report (96-14) . . . . . . . . . . . . . . . . . . 20
E8.4 (Closed) Licensee Event Report (96-15) . . . . . . . . . . . . . . . . . . 20
E8.5 (Closed) Licensee Event Report (97-01) . . . . . . . . . . . . . . . . . . 20
IV. PLANT SUPPORT (71707, 71750, 93702) . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
R1 Radiological Protection and Chemistry Controls ................. 21
R 1.1 General Observations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
R1.2 Automatic Trip of the Augmented Offgas System / Building and
Radioactive Airborne Contamination Due to Subsequent
Equipment Failure ................................. 21
S1 Conduct of Security and Safeguards Activities . . . . . . . . . . . . . . . . . . 22
S1.1 General Observations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
V. M AN AG EM ENT MEETI NG S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
X1 Exit Meeting Summ ary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 J
X2 NRC Region i SALP Management Meeting and Plant Tour . . . . . . . . . . 23 j
ATTA C H M E N T 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 !
ATT A C H M E N T 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
ATTA C H M E NT 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
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Report Details
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! Summarv of Plant Status
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The plant operated at full power until January 24,1997, when plant operators reduced j
j power to 40% for main steam isolation valve quarterly surveillance testing (valve closure i
test). Reduced power ope ation (at about 63%) continued for various other planned
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maintenance activities until January 25,1997, when full power operation resumed. On
February 11,1997, the "E" reactor recirculation (RR) pump tripped due to an associated j
4160 volt motor supply cable failure. Subsequently, while increasing reactor power with i
the remaining four RR pumps, the "C" RR pump tripped on February 12,1997, placing the )
unit in three loop operation, which is prohibited by plant technical specifications. ;
Accordingly, a plant shutdown was promptly initiated per technical specification
requirements. The "C" RR pump was restarted within about three hours, and the ]
shutdown was terminated at approximately 74% power.
Reactor operation was increased to 98% (limited because of four loop operation) during the i
ongoing cable replacement activities for the "E" RR pump motor-generator set. The cable
replacement and testing activities were completed on February 21,1997. Reactor power
was then returned to 100% and full power operation continued through the remainder of
the inspection period,
l. OPERATIONS (71707, 93702,40500)
01 Conduct of Operations'
01.1 General Comments
The inspectors conducted frequent reviews of ongoing plant activities and operations using i
the guidance in NRC inspection procedure 71707. The inspectors observed plant activities j
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and conducted routine plant tours to assess equipment conditions, personnel safety
hazards, procedural adherence and compliance with regulatory requirements. !
Control room activities were found to be well controlled and conducted in a professional l
manner with staffing levels above those required by Technical Specifications. The
{ inspectors verified operator knowledge of ongoing plant activities, the reason for any lit
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annunciators, safety system alignment status, and existing fire watches. The inspectors l
also routinely performed independent verification from the control room indications and in
the plant that safety system align nent was appropriate for the plant's current operational
mode.
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f ' Topical headings such as 01, M8, etc., are used in accordance with the NRC standardized
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reactor inspection report outline. Individual reports are not expected to address all outline
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topics.
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Since startup from the recent 16R refueling outage, one of the onshift senior reactor
operators (SROs) was moved to a new location within view of the controls. Previously, no
SRO was stationed within view of the controls, although the SRO office was within the
control room area. This move was initiated by station and operations management in order
to increase SRO direct oversight and control of both routine and non-routine activities, in
addition, the move was an attempt to abate a recent adverse trend in the number of ;
personnel errors, and to provide additional control room access control (traffic and !
distraction reduction). During periodic control room tours, the inspectors observed ;
effective oversight and control of control room activities by both the SRO and the lead i
CRO.
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The inspector observed some of the activities associated with the January 24 - 26,1997,
planned power reduction in particular, control room activities while placing the "C"
reactor recirculation pump were well controlled. A pre-evolution briefing was conducted by
the control room SRO as per reactivity management practices. Operator distractions were
minimized during the activity. Overall, the activity was very well controlled and executed.
01.2 Taaaino Error on Control Rod Hydraulic Control Unit (Violation 97-01-01)
a. Inspection Scope (71707) i
The inspector reviewed the circumstances concerning an apparent tagging error that
occurred on January 25,1997, during the scheduled power reduction for i
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maintenance and surveillance activities. The inspector reviewed the tagging order,
schematics of the hydraulic control unit, and interviewed personnel involved. The
valving error resulted in a spill of about 250 gallons of control rod drive (CRD) water
(high quality condensate water) on the 23 foot elevation of the reactor building,
b. Observations and Findinos
On Saturday, January 25,1997, at about 1:00 a.m., when hydraulic control unit
(HCU) 18-39 was being tagged out, it was reported to the control room that water
was leaking from the HCU. The water was determined to be from the HCU vent
valve (107 valve). The leak was isolated by operations department personnel
wearing plastics to reduce the possibility of personnel contamination. There were
no personnel contaminations as a result of this occurrence. The licensee
determined, based on the sump pump run times, that about 250 gallons of water
had leaked through the open vent valve. The water was directed into a floor drain
and the area was mopped. The first gross swipe sample (area greater than 100
square centimeters) for contamination indicated 200 to 400 counts per minute
above background. Following additional cleanup the area was less than 100 counts
per minute above background with a gross swipe sample. The licensee's
' Topical headings such as 01, M8, etc., are used in accordance with the NRC standardized
reactor inspection report outline. Individual reports are not expected to address all outline
topics.
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radiological controls field operations manager noted that the contamination level
would have been less than 100 counts per minute on the first count if the standard
100 square centimeter swipe sample had been taken instead of the more
conservative gross swipe sample.
During the discussions, operations personnel noted that the tagging request was
received on January 24,1997. The request asked for a standard outage and !
identified the component to be isolated as V 305-0101, which is the manual insert
isolation valve to the control rod drive unit. The work description was to replace
the solenoid on V-305-0118. This valve number conflict caused some confusion
and resulted in a telephone call to the requestor. It was determined that the work
to be performed was replacement of the solenoid on V-305-0118, not V-305-0101.
It was also communicated during the telephone call that the HCU would be tagged
out without cooling water supplied, and the solenoid valve would require electrical
isolation. '
Several discussions subsequently occurred between the operations crew concerning j
whether the HCU should be tagged out with or without cooling water. Operations l
ultimately decided to tag the HCU with cooling water supplied. When the tagging !
order was finally issued, the operator missed changing the position of V-305-0107 i
valve from open (cooling water not maintained) to closed (cooling water maintained) l
from the prior version of the tagging order. This resulted in a direct flow of control j
rod drive cooling water at about 1050 psig to the reactor building floor when the l
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scram inlet and outlet pilot valves were de-energized in accordance with the tagging
order. An additional complication was the fact that, as part of the isolation, the air
supply to the scram pilot valves and the scram inlet and outlet valves was closed
and prevented the repositioning of the scram inlet and outlet valves to stop the leak
by re-energizing their pilot valves.
Additional discussions with operations personnel identified that a diagram had not
been used to verify that the correct valves were being tagged, and the immediate
supervisor or another operator did not verify that the tagging order was correct for
the desired condition (isolated with cooling water maintained). In addition, a
standard tagout exists in the computerized tagout system for valves. Electrical
information must be manually added. However, a standard tagout was not used.
The inspector discussed this event with licensee management. The inspector noted
several weaknesses. The lack of performing an independent verification of the
tagging request was the most significant because a separate review may have
identified this error. The licensee stated that the tagging procedure (No.108.7,
" Lockout /Tagout Procedure") had been revised several years ago to eliminate the
second verification requirement in the preparation of the tagging order. The second
verification was removed to shift the responsibility for determining the initial
boundary requirements to the requesting party. That is, an accurate and properly
reviewed tagging request by the requesting party, coupled with a separate review
by the operator (tagging authority) while processing the tagging request, in effect,
would constitute a second verification.
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Discussions with control room operators indicated that most tagging requests
require some modification prior to placement of tags. The need for control room
operators to modify or correct tagging requests is a strong indicator that the
responsibility for properly developing accurate tagging requests is not being )
assumed by the requesting party. Failure of the requesting party to provide a
detailed and correct tagging request essentially makes the control room operator the
requestor and verifier, thereby eliminating a second check. I
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The inspector noted that in accordance with procedure 108, " Equipment Control," i
placement of tags does require an independent verification. That was done in this
case. However, since the tagging order was incorrect, the independent verification
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of the tagout execution would not have prevented this occurrence. 1
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c. Conclusions
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The inspector concluded that there were several weaknesses associated with this
ocenrrence: 1) the tagging request was poorly prepared and did not adequately l
specify the number and placement of tags,2) the tagging request was not i
submitted until the day that the power reduction was scheduled to take place and
operations personnel were somewhat focused on power reduction activities,3) the
standard tagout was not used as a starting point,4) tne tagging authority did not
use a print or diagram to verify proper system status and configuration, and 5) there
was no independent verification or qualitative requirement to verify that the tagging
order was correct. Failure of procedure 108.7 to establish controls that ensure
activities affecting quality are satisfactorily performed is a violation of 10 CFR 50, i
Appendix B, Criterion V, " Instructions, Procedures, and Drawings." (VIO 50-
219/97-01-01)
01.3 "B" Reactor Recirculation Pomo Flow Fluctuations
a. Inspection Scope (71707,37551)
On February 20,1997, control room operators and the shift technical advisor (STA)
noted that the "B" reactor recirculation (RR) pump flow had decreased over about a
21 hour2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br /> period. The inspector reviewed the associated trend graphs and deviation
report, and monitored the licensee's followup actions.
b. Observations and Findinas
Control room operators record individual RR pump flows every four hours. On I
February 20,1997, the plant was in four loop operation due to the inservice cable
f ailure on the "E" RR pump (Section M1.5 of this report). Individual flows for the
four RR pumps were between 36,000 gpm and 37,500 gpm. A control room
operator noted a slight change in the gross numbers obtained from control room ,
indicators, and notified the STA to request retrieval of additional data. The STA I
obtained graphs for the four operating RR pumps for the period 12:00 a.m. to 9:00
p.m. on February 20,1997. The resulting computerized plot identified a reduction I
in total RR flow rate of about 750 gpm between 5:00 p.m. and 6:00 p.m., and a
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total reduction of about 1300 gpm over the entire 21 hour2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br /> period. Trend plots of
the individual RR pumps identified the reduction to be attributed to the "B" RR
pump. Other system parameters remained normal and stable.
The STA documented the condition in a deviation report. System engineering was
infoimed of the identified condition and was requested to commence a review.
Additional data was collected and reviewed. The data indicated that the "B" RR
pump speed signal became " noisy" during the time of reduced RR flow. That is, the
peak-to-peak band in the speed signal, that normally is about 0.2 Hz, increased to
about 1.0 Hz (peak-to-peak band) while flow was reduced. After flow returned to
normal, again without operator action (around 11:30 p.m. on February 20), the
speed signal band returned to 0.2 Hz. The speed signal and RR pump flowrates
were monitored for several days. By the end of the inspection, no additional
anomalies had occurred. The licensee was continuing to monitor and evaluate data,
and they were considering to plan a tachometer replacement during the next on-line
maintenance window.
c. Conclusions
The operators and STA were alert to identify and trend the observed flow reduction
for the "B" RR pump. System engineering promptly responded and began collecting
additional data in an attempt to identify the problem. However, since a problem
was not identified, additional monitoring continued at the end of the inspection.
07 Quality Assurance in Operations
07.1 General Office Review Board Periodic Meetina
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The inspectors attended portions of the bi-monthly General Office Review Board '
(GORB) meeting that was conducted at Oyster Creek on February 5 and 6,1997.
This GORB meeting was a combined Oyster Creek /Three Mile Island committee
meeting. The inspectors attended sessions presented to the GORB in the areas of .
operations (status and significant events) and engineering. The inspector concluded
that the board's discussions were probing and constructively critical of station "
activities, and were focused on plant safety.
07.2 Emolovee Group Meetinas
On January 20,1997, the Vice President / Director, Oyster Creek and the President,
IBEW Local 1289 issued a memorandum to all Oyster Creek employees to advise
them of a series of upcoming employee meetings whose focus would be on
improving human performance at Oyster Creek in the wake of the results of recent
industry and regulatory reviews and evaluations.
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The inspector attended one of the meetings on January 30,1997, which was well-
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attended. A one-page handout was provided to all attendees that addressed safe
work practices, employee accountability and learning from mistakes.
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The inspector noted that, although the presenters provided sufficient focus on
safety, human performance and accountability, much of the employee concern
centered on the financial and operational future of Oyster Creek. In addition,
several of the attendees expressed concern that attendance for these meetings was
optional. The VP/ Director, Oyster Creek responded that the material presented and l
discussed would be incorporated into required employee training, thereby exposing
all employees to the subject matter.
The inspector concluded that licensee senior management's efforts to communicate
work performance expectations was notable. However, much of the discussion
shifted away from worker performance to other matters.
08 Miscellaneous Operations issues
08.1 Periodic Report Review
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The monthly operating report for January 1997 was reviewed and found to be !
acceptable. 1
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11. MAINTENANCE (61726, 62707, 90712, 92902)
M1 Conduct of Maintenance l
M1.1 Maintenance Activities 1
a. Insoection Scoce (62707)
The inspectors observed selected maintenance activities on both safety-related and ;
non-safety-related equipment to ascertain that the licensee conducted these '
activities in accordance with approved procedures, Technical Specifications, and
appropriate industrial codes and standards. The inspectors observed all or portions
of the following job orders (JO):
e JO 513365, " investigate Vibration for No.1 Dilution Pump" !
- JO 513839, " Replace Cable on "E" Recirculation Pump Motor Generator Set"
e JO 512916, " Remove Double Blade Guides From Fuel Pool"
e JO 511552, " Core Spray System 480 Volt Breaker (N203B) Preventive
Maintenance"
b. Observations and Findinas
The inspectors concluded that the above activities had been approved for
performance and were conducted in accordance with approved job orders and
applicable technical manuals and instructions. Personnel performing the activities
were knowledgeable of the activities being performed and were observing
appropriate safety precautions and radiological practices.
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M1.2 Surveillance Activities l
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a. Inspection Scoce (61726)
The inspectors performed technical procedure reviews, witnessed in-progress
surveillance testing, and reviewed completed surveillance packages. They verified
that the surveillance tests were performed in accordance with Technical
Specifications, approved procedures, and NRC regulations. The inspectors reviewed
portions of the following surveillance tests / procedures:
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e 609.4.001, " Isolation Condenser Valve Operability and In-service Test" !
- 617.4.002, " Control Rod Drive and Flow Test"
o 602.3.004, "Electromatic Relief Valve Pressure Sensor / Pilot Control Relay -
Test and Calibrate"
e 636.4.003, " Diesel Generator Load Test"
1
b. Observations and Findinas
A properly approved procedure was in use, approval was obtained and prerequisites
were satisfied prior to beginning the test. Surveillance test instrumentation was
properly calibrated and used, radiological practices were adequate, technical ,
specifications were satisfied, and personnel performing the tests were qualified and ,
knowledgeable about the surveillance test procedure, j
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M1.3 Routine Maintenance and Surveillance Activities Conclusions ,
The maintenance and surveillance activities observed by the inspectors were
conducted safely and in accordance with station procedures.
M1.4 Licensee Investiaation of No.1 Dilution Pumo Vibration
a. Insoection Scoce (62707)
The inspector attended the diver pre-briefing and observed portions of the dive
conducted on February 4,1997, to inspect the No.1 dilution pump.
b. Observations and Findinas
On February 4,1997, the inspector attended the pre-briefing for the planned dive
into the No.1 dilution pump bay. The briefing was conducted using procedure
1000-ADM-1101.01, " Underwater Diving Safety." The inspector noted that the
briefing discussed who was in charge of the activity and safety practices that must
be followed. The licensee also discussed areas to be inspected using a diagram of
the pump assembly. The diver war informed of different possible causes for the
rumbling vibration, including foreign materialin the pump.
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During the dive, a small camera was used to allow real time video inspection by
engineering personnel. Industrial safety personnel were also present at the dive
site. The cause of the rumbling vibration was identified as the pump impeller
rubbing on the pump casing. What caused or allowed the lateral movement of the
impeller is unknown at this time. The pump is scheduled to be worked the week of
March 24,1997. Following pump removal and disassembly, a root cause will be
determined. The licensee also intends to install some vibration monitoring sensors
on the No.1 dilution pump when it is repaired to allow monitoring and trending
during operation. The licensee is also evaluating the placement of vibration
monitors on the other two pumps while they are installed.
c. Conclusions
The inspector determined that the licensee had approached this task with a high
level of safety. The installation of vibration monitoring sensors on the No.1 pump
was a positive first step to more actively monitor the performance of all the dilution
pumps.
M1.5 "E" Recirculation Pumo Motor Generator Set Cable Replacement
a. Insoection Scone (37551. 62707)
The inspector followed the licensee's 4160 volt cable replacement activities for the
"E" recirculation pump motor generator (RPMG).
b. Observations and Findinas
On February 11,1997, at 8:06 p.m., the "E" RPMG 4160 volt motor supply cable
failed. The plant responded normally to the loss of one recirculation pump.
Subsequent investigation by the licensee indicated the " flag" on the ground sensing
relay had picked up. Subsequent investigation by electrical maintenance persrsnnel
identified a short of the "B" phase to ground. During the period of February 12
through 21,1997, the licensee replaced the cables for the "E" RPMG set. The
recirculation pump was restar:ed and placed in service on February 21,1997, at
12:10 p.m. During the cable replacement activities, the inspector made routine
observations of ongoing activities and cable testing. The failed cable was
" Anaconda," size 0000, EPR unishield insulation, and had been installed in 1984.
The cable was replaced with "Cablec," size 0000, improved EPR insulated cable.
The installation was completed without incident. Personnel followed the directions
in the job order. Engineering provided strong oversight and support of the activities
including the design and rerouting of a section of conduit. The conduit was
rerouted because of a misalignment of the conduit where it passed between the
reactor building and the turbine building basement. A second benefit of the conduit
rerouting was a reduction in personnel exposure. The old routing passed through
the reactor building equipment drain tank (RBEDT) room, a locked high radiation
area. The licensee estimated that the re-routing of the conduit saved over one rad
of personnel exposure.
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The inspector also reviewed the results of the 5000 volt megger tests and the 35
kilovolt high pot test. The 10 kilovolt high pot of the cables and motor after the i
cables were reconnected was also reviewed by the inspector. New cable insulation I
resistance at 5000 volts, after 10 minutes, was greater than 100,000 megohms, I
with both positive and negative polarity. At 35 kilovolts, after 5 minutes, leakage I
current was 0.5 microamps which equates to a resistance of 70,000 megohms.
Leakage current of the cables when connected to the motor was 5 microamps after
5 minutes at 10 kilovolts or 10,000 megohms. These results satisfied the
associated acceptance criteria.
c. Conclusion
The inspector determined that the cable replacement was completed without error.
Personnel followed applicable instructions and engineering provided strong support ;
to maintenance personnel. Conduit rerouting modifications were effectively l
implemented. l
M7 Quality Assurance in Maintenance Activities
M7.1 Failure of Limitoraue Valve Operator
a. Insoection Scoce (40500. 62707. 71707)
The inspector reviewed the licensee's actions concerning the failu e of two
Limitorque valve operators. The failures were recently (January 27,1997) reported
to the NRC by Limitorque Corporation as a counterfeit parts issue. The inspector
also supplied licensee information concerning the motor operator failures and the
licensee's actions to the Vendor inspection Section of the NRR's Special inspection
Branch for additional followup,
b. Observations and Findinas
On October 8,1996, the licensee issued deviation report (DR)96-870 to document
the failure of a Limitorque motor operator for valve V-3-29. A similar failure had
previously occurred on V-3-13. These valves are 72 inch valves in the non-safety
related circulating water system. The motor operators were SMB-1 size.
The failures occurred after the valves were operated in manual and would not return
to the motor operation mode. The licensee determined that the worm shaft clutch
gear tripper pin had fallen out preventing the operator from returning to motor
operation. The licensee also noted that the operators were not supplied by
Limitorque but had been refurbished by a different contractor for use in non-safety
related applications.
The failed components (worm shaft clutch gear and tripper pin) were sent to
Limitorque for analysis and failure determination. On October 11,1996, Limitorque
informed the licensee that the components were not manufactured by Limitorque
and had dimensional and material deficiencies. The licensee informed other
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10
licensees of this issue through a " nuclear network" report on October 15,1996,
following the Limitorque notification. On January 27,1997, Limitorque made an
informational report to the NRC of the existence of a " counterfeit" critical
component in these non-safety related valves. Following Limitorque's report to the
NRC, multiple inquiries from other NRC groups were received at the resident office
concerning the failures and the possible wider industry wide implications.
Following the second valve failure at Oyster Creek, the licensee issued a second DR
and performed a broad based evaluation of records of all motor operators that were
obtained from the subject vendor. There were three additional motor operators of
the specific size (SMB-1) with the specific gear size that had failed. All were
installed in the circulating water system and all three have had the gear and pin
replaced with Limitorque parts. There were a total of 15 motor operators installed
in the plant that were not obtained from Limitorque, allin non-safety related
systems and all had been satisfactorily MOVATS tested during the Fall 199616R
outage. The licensee noted that performance during MOVATS testing did not
preclude a future failure but indicated satisfactory performance when tested. The
inspector questioned the licensee concerning any Limitorque operators that might be
in the warehouse. The licensee stated that all valve operators in question had been
installed and tested.
Limitorque also me aned that they used a proprietary process to expand the pin
that had come out m the failed motor operator for the two valves. This indicates
that the process of installing the pin and worm shaft clutch gear was likely very
significant in the failure of the motor operator, as well as the " counterfeit" parts.
c. Conclusions
The inspector concluded that the licensee had properly addressed the two failures
of Limitorque motor operators used in non-safety related applications. The licensee
promptly verified that the facility had not used any of the non-Limitorque supplied
operators in any safety application.
M8 Miscellaneous Maintenance issues
M 8.1 (Closed) Licensee Event Reoort (LER) 96-13: Motor Control Center (MCC) DC 2 did
not meet seismic design bases. The licensee identified that prior work performed by
contractor maintenance personnel during the 16R refueling outage failed to re-install
the MCC DC-2 mounting bolts, rendering the safety related MCC inoperable. This
occurrence was discussed in detail in NRC Inspection 50-219/96-11 (Section
M8.2). This LER is closed.
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Ill. ENGINEERING (37551,40500,71707,92903)
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E1 Conduct of Engineering !
E1,1 As-Found Field Chanae Notice (FCN) Technical Review and Acoroval Deficiencies
!
- a. Inspection Scope (37551,71707)
On February 18,1997, the licensee identified that a significant number of Field i
Change Notices (FCN) have resulted in drawing changes, but did not receive the
- necessary technical review / evaluation. The inspector reviewed the associated ,
deviation report, interviewed engineering personnel, reviewed the controlling
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administrative procedure for the FCN process, and reviewed a sample of unreviewed l
FCNs to determine the significance of this issue.
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b. Observations and Findinas
.
. The deviation report documented that approximately 940 FCNs resulted in
j procedure changes without receiving technical reviews. At the time the deviation ;
report was submitted, a review of all FCNs (about 20,000 for Oyster Creek) was -
continuing to determine the full magnitude of the problem. By the end of the
, inspection, the total number of affected FCNs was about 970.
- The licensee believed that the large backlog of technical reviews of these FCNs was
due to individual engineers placing a relatively low priority on them due to an :
apparent low safety significance (based on an FCN initial screening). The licensee f
identified this backlog while assessing turnover work loads for corporate engineers
4
following the recent Engineering Department reorganization (Summer - Fall,1996).
The majority of the backlog of FCNs dated from 1985 to 1993. In 1993, when
system engineering organization was instituted, the site system engineers became
'
responsible for the reviews, and the backlog was better managed.
The licensee conducted a broad assessment of the FCN backlog and determined
that these were "As-found" FCNs, meaning that the FCNs requested a drawing or
technical manual change to reflect the as-built condition of the plant. The licensee
determined that these are typically administrative in nature and do not affect the
design or function of components or systems as described in the UFSAR.
Consequently, the licensee concluded the safety significance of not having complete
technical reviews of these As-found FCNs did not impact operability.
Notwithstanding the low safety significance, the licensee recognized that the large
number of open As-found FCNs represented a concern. Accordingly, they have
initiated an effort to complete the required technical reviews for all of the nearly
1000 open FCNs. A list of these FCNs has been developed, and a project manager '
has been assigned to coordinate the licensee's efforts.
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The inspector independently reviewed 95 FONs selected from the licensee's list.
The majority of them were administrative in nature. Sixteen of them were identified
to the licensee as potentially having higher safety impact either due to the lack of
detailed information in the document or because the FCN involved a nuclear safety-
related system. The licensee promptly reviewed those 16 FCNs and determined 1)
what the change was,2) the safety significance, and 3) whether a safety evaluation
was required for close-out of the FCN. Their review concluded that none of them
were of safety significance and none required a safety evaluation. Six of them were
closed out during the review, and the remaining 10 required additional detailed
review to complete close-out. The inspector reviewed the licensee's response and
found it to be acceptable.
Station Procedure EMP-015, " Engineering Change Documents," requires that
Engineering Change Documents (ECD, formerly FCNs) receive a technical review
and technical approval. Although the procedure does not identify a required time
frame by which the review and approval must be done, an excessive number of As-
found FCNs were not technically reviewed and approved in a timely fashion. This
licensee-identified violation of station procedure EMP-015 was of low safety
significance and will be corrected within a reasonable time; and is therefore being
treated as a Non-Cited Violation, consistent with Section Vll.B.1 of the NRC
c. Conclusions
The excessive number of As-found FCNs that had not received technical review and
approval indicated weak management of the engineering change document process
and is a non-cited violation. The licensee's followup actions to their self-
identification that a significant number of FCNs did not receive the appropriate
technical review and approval were acceptable.
E1.2 Followuo and Evaluation for Safetv-Related Relav Failures Due to Manufacturina ;
Defect (Unresolved item 97-01-02)
a. Insoection Scone (37551. 40500. 71707)
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NRC Inspection Reports 50-219/95-06 and 50-219/95-14 discussed inservice l
failures and associated licensee followup of General Electric (GE) CR120AD,120
Vdc relays that were purchased from a vendor, Farwell & Hendricks, Inc. (F&H).
The licensee subsequently identified a similar but related problem (same defect) on
the same relays purchased directly from GE. The inspector reviewed the associated
deviation report (DR) the discussed the status of ongoing testing and evaluation
activities with onsite engineering personnel.
b. Observations and Findinas
Following Oyster Creek's 15R refueling outage (Fall 1994), three GE CR120AD,120
Vdc relays failed within three months of completing the outage activities. Nineteen
relays were replaced during that outage. GPUN, Inc. purchased the 19 relays as
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safety related components from F&H, who in turn, purchased them commercially
from GE and then dedicated them as safety related relays. The F&H dedication plan
,
for the relays had been approved by a GPUN, Inc. representative.
, independent failure analysis for the relays identified a manufacturing defect as the
cause for the failures. Specifically, the start-end of the coil was off the insulating
.
lead pad and was in contact with the outer layer of the coil winding (near the finish- !
l end of the coil). The affected length of coil wire and insulation was placed in a high
electrical stress condition that led to dielectric breakdown at the failure site, thus
effectively short circuiting the coil. The resulting high current through the short
circuit caused the coil wire to fuse and produce an energetic arc at the failure site.
Following the three failures and failure analysis results, the licensee 1) placed the
vulnerable relays on "QA-hold," to prevent installation, 2) notified F&H of the failure
analysis results for 10 CFR Part 21 reportability applicability review, and,3) notified
the nuclear industry of their experiences with these relays via the Nuclear Network.
Additionally, F&H subsequently developed a specific bench test which would
identify the presence of the defect.
On February 4,1997, the licensee submitted a deviation report identifying problems
with four GE CR120AD,120 Vdc relays that were purchased in 1994 directly from
GE as safety related components. Specifically, one of those relays was found with
essentially an identical failure site and mechanism as the other relays purchased
from F&H. In the Summer of 1996, GPUN, Inc. had sent that GE-supplied safety
related relay (the other three were installed in the plant) to F&H for bench testing to
determine whether the defect was present as part of their enhanced testing j
program. The associated August 1996 report from F&H identified the same failure
site for that GE-supplied relay. Subsequently, that same relay, as well as an
additional in-stock relay that had previously passed the F&H special test, were sent
to another independent vendor for destructive physical analysis to confirm the
August 1996 findings. The completed analysis report, dated January 7,1997,
confirmed the same type and location of failure for the GE-supplied relay, while no
failure site was identified on the " good" F&H dedicated and tested relay.
Following the initial identification of this issue after 15R, the licensee addressed
operability concerns for the installed relays. That included assessing the function
and failure mode for each of the installed relays, including indications of a failure to
the control room operators. They also reviewed the inservice test history for each
of the relays, and determined that sufficient testing or cycling was performed to
provide assurance that the relays were operable. As an additional conservative
action, the licensee replaced 17 of the installed relays during the recent 16R
refueling outage with those from in-stock storage. However, due to an apparent
communication weakness, only 10 of the 17 had been tested by the F&H special
test procedure. As a result, the licensee performed a similar operability assessment
to that which was done previously for the 17 relays. The associated Conditional
Release listed the function of each of the 17 relays, the normal state (all are
normally energized), and the impact of a relay failure. In addition, the licensee
noted that based on current knowledge and experience, the failure mode of the
specific manufacturing defect typically results in a pre-mature failure (immediate to
three months). The relays had all operated in excess of five months.
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l At the end of this inspection, there were two issues related to 10 CFR Part 21
-reporting. The licensee informed the inspector that F&H had previously indicated to
them (GPUN Inc.) that F&H submitted a 10 CFR Part 21 report for the relays that
they dedicated and provided to Oyster Creek as safety related. However, it was not
, apparent that the associated report was ever completed and submitted to the NRC. ;
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The second issue is more recent and is related to the relays supplied directly by GE
- as safety related components. There appears to be a conflict in determining that
the failed relay in question is in fact the GE-supplied relay. This must be resolved in
order to determine proper reporting and characterization, and is important in
determining the generic nature of this issue. Pending resolution of these two
issues, this is an unresolved item. (URI 50-219/97-01-02)
c. Conclusions
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The inspector concludd that the licensee had provided appropriate attention to the
outstanding issue of whether relays for safety related applications are properly
tested and monitored. The licensee's conditional release was acceptable, although '
l it became necessary only due to a communication weakness. Continued aggressive
followup on this issue is warranted to achieve full resolution.
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E2 Engineering Support of Facilities and Equipment
E2.1 "C" Recirculation Pumo Motor Generator (RPMG) Set Trio
a. Inspection Scoce (37551. 71707)
The inspector reviewed the safety determination and procedure change that allowed -
an increase of the high current limit of the RPMG set motors and subsequently
resulted in a trip of the "C" RPMG.
b. Observations and Findinos
Following the failure of the "E" RPMG set cable (see section M1.5 of this report),
the licensee continued operation with four of the five recirculation loops in
operation. With only four loops in operation, the plant could not attain full power
because the "C" RPMG set motor current reached its administratively controlled
high limit of 210 amps. The limit was reached when recirculation pump speed was
increased to raise plant power following the "E" recirculation pump trip. The "C"
RPMG motor current runs slightly higher than the other RPMG sets. Maximum
power at the time was about 97 percent. Since the plant was expected to be in the
four loop configuration for an estimated 10 to 12 days, operations management
requested engineering to evaluate and recommend a means to increase reactor
power to 100 percent.
Engineering evaluated the options possible and decided to increase the motor
current limit to 235 amps. A safety determination was performed by engineering
and a procedure change was implemented. A crew briefing was conducted prior to
.
15 1
increasing the speed of the recirculation pumps. The system engineer was also
present in the control room monitoring the RPMG set motor amp indicators. When
control room operators increased pump speed, the "C" RPMG set voltage and
current became unstable at about 220 to 225 amps and the RPMG set tripped on
loss of field in about 2 seconds. The trip occurred at 6:35 p.m. on February 12, {
1997. The loss of the second recirculation pump resulted in a power decrease to ;
about 94 percent and placed the licensee in a Technical Specification (TS) 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> I
required shutdown. A shutdown was promptly initiated by control room operators.
Electrical maintenance personnel checked the "C" RPMG and its voltage regulator.
No problems were identified, and the "C" recirculation pump was restarted and
placed in service at 9:45 p.m., and the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shutdown was terminated. Power
had been reduced to 74 percent before exiting the applicable TS. The plant power
was increased, and reached 98 percent at 2:20 a.m. on February 13,1997. Power
was restricted at the previous 210 amp limit on the "C" RPMG motor.
The inspector questioned the licensee to determine if non-conservative or
inappropriate decisions had led to the "C" RPMG set trip. The inspector determined
that the increase in RPMG set motor current was within the nameplate rating of 239
amps. The ability of the voltage regulator to control voltage at the higher current
levels was also questioned. The licensee noted that the voltage regulator had been
completely refurbished during the last outage with numerous components replaced.
The voltage regulators had been very stable during the current operating cycle in
five loop operation. Some oscillations had occurred during previous cycles. The l
system engineer observing the motor amps stated that at 210 amps on the "C" l
RPMG (starting point for this evolution), there was some minor oscillation. The i
voltage regulators during the previous operating cycles had general'y displayed
instability that increased with load such that load increase could bo stopped before
an RPMG set tripped. Based on current cycle indication and the recent
refurbishment the engineering staff thought that the regulators would be capable of
regulating voltage at the higher motor current levels.
The discussions did identify, that due to system design and recirculation pump
restrictions, the licensee does not have the ability to align the voltage regulators in
accordance with the voltage regulator technical manual. The technical manual
alignment procedure discusses load application and rejection and adjustment from
zero to fullload. These adjustments cannot physically be accomplished. Load
application and rejection is not possible without stopping and starting the pump
because the RPMG output to the recirculation pump does not have a breaker in the
circuit.
Maximum recirculation pump speed (RPMG load) when cold is restricted to less than
36.5 Hz due to vibration concerns. Speed was not restricted prior to 16R;
however, the root cause of a recirculation pump bearing failure when coming out of
the last refueling outage was determined to be vibration due to high pump speeds
while cold. There are also restrictions on pump speed balance between loops when
hot due to flow induced vibrations. The inspector asked how the regulators were
aligned with all the pump restrictions. The system engineer stated that the
regulators were set to the original settings after refurbishment and checked at 35
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Hz when first started to ensure voltage and current were within specifications. [
Observations during startup up to full power with five loops in operation were quite
stable, with voltage and currents at the expected values.
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Licensee management noted that further evaluation concerning possible methods to i
adjust the regulators at the high end of the current output were being evaluated as )
, well as possible modifications to further stabilize the voltage regulator. In the
interim the licensee has restricted RPMG generator output current to 210 amps
during four loop operation.
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i Additional licensee investigation into the background information concerning this
event identified a trip of the "D" RPMG set on February 12,1995, due to voltage
, regulator instability during four loop operation. A Deviation Report (95-074) was
! issued, with refurbishment of the voltage regulators as a long term corrective
,
action. Refurbishment was accomplished during the 16R outage. !
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The inspector concluded that although a procedure to effectively adjust the RPMG
,
sets voltage regulator was not available (such a procedure may not be possible due
, to recirculation pump operating restrictions and system design), the licensee had
, made reasonable effort to return regulator adjustments of this important to safety
- equipment to the original settings and verified proper regulator response during
- power ascension. Based on knowledge of regulator refurbishment and observations
l of stable voltage regulator response since restart from 16R, the licensee had taken i
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reasonable steps to consider increasing the motor current limit in order to increase
, reactor power. However, because 1) the licensee observed a minor oscillation at i
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210 amps during the increase (prior to the trip at about 225 amps),2) it is - q
recognized that an effective voltage regulator adjustment was not possible,
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particularly at higher RPMG set speeds,3) there have been prior and repeated l
RPMG set operational problems, and 4) the RPMG sets play an important role in I
reactivity management, the inspector concluded that the licensee's decision to
- proceed did not reflect a conservative approach.
E2.2 Isolation Condenser Vent Radiation Monitors Removed From Service Prior to
Addressina All Relevant UFSAR Commitments (Unresolved item 97-01-03)
a. Inspection Scoce (37551,40500,71707)
.
On February 6,1997, the licensee submitted a Deviation Report (DR) after they
i identified that the isolation condenser vent tradiation monitors were previously
removed from service via a plant modification without identifying that the radiation
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monitors fulfilled a NUREG 0737 (Three Mile Island Action Plan) commitment. The
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inspector reviewed the DR, the safety evaluation that was used to support the ,
modification, applicable sections of the UFSAR, NUREG 0737, and meeting minutes
j of a February 7,1997, Plant Review Group (PRG) meeting. In addition, the ;
- inspector discussed the details and the implications of not meeting the associated !
NUREG 0737 commitments with both licensee and NRC personnel. j
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b. Observations and Findinas
in December 1995, the licensee removed from service the isolation condenser (IC)
vent radiation monitors. A safety evaluation was completed at the time to support
the modification. Although the safety evaluation recognized and noted that UFSAR
Section 11.5.2.3, " Containment Spray Heat Exchanger / Service Water Area Monitors
and IC Vents Monitors," needed to be addressed, other UFSAR sections were
missed. The most significant section that was missed was 1.9.31, " Item II.K.3.14 -
Isolation of ICs on High Radiation." That section documents the NRC Position on
the issue and the GPUN Response. The UFSAR section documents that the NRC
staff has concluded that the IC manual trip on high radiation levels at the vents is
sufficient to provide the amount of flexibility and system availability intended by this
item.
, The function of the IC vent radiation detectors was to provide a leak detection !
indication to the control room operators so that they could manually isolate the
affected IC upon a tube leak from the reactor coolant system, thereby preventing a
release of radioactivity to the environment. However, the licensee stated that the
operational characteristics of the system represented a potential source of operator
confusion since background radiation in the vicinity of the radiation monitors with
, the ICs in service masked their capability for leak detection (i.e. due to expected
, radiation levelincrease for normal IC system operation without a tube leak). -
The intent of NUREG 0737, item II.K.3.14, was to have licensees change the
source for the IC automatic isolation signal due to high radiation from the steam
d
lines (that lead to the ICs) to the IC vents. That is, the design was to be modified
such that the ICs were automatically isolated upon receipt of a high radiadon signal
from the IC vents rather than at the steam line for the purpose of increasing IC
3 availability as heat sinks (preventing spurious isolations), in an April 30,1981,
letter to the NRC, GPUN stated that Oyster Creek uses excessive flow in the steam
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lines to and condensate lines from the ICs as the only isolation signal for the system
isolation valves. GPUN further stated that because the Oyster Creek IC system is
different from the one described in the NUREG, no additional modifications were
required. The NRC's response letter, dated December 18,1981, stated that
GPUN's April 30,1981, response was acceptable and the item was considered
resolved.
The current licensee's position is that the intent of NUREG 0737, item K.ll.3.14 is
met by the excessive flow sensors alone. They further believe that if the vent
radiation monitors were continued to be used at Oyster Creek to initiate a manual
isolation, the situation that the NUREG ltem was attempting to avoid (unwanted and
unnecessary isolations) would be created. The licensee also stated that Oyster
Creek currently relies on a combination of procedurally directed on-site monitoring
and the use of other control room indications / alarms to alert the operators to the
need to manually isolate one or both of the ICs.
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The inspector's review of the NRC December 18,1981, safety evaluation report
(SER) confirmed that the SER was generic in nature in that seven nuclear plants, I
including Oyster Creek, were addressed. However, the SER recognizes that all the
plants have radiation monitors and alarms at the IC vents, and that six of the seven ;
(including Oyster Creek) require manual isolation of the IC if considered necessary '
by the operators.
The licensee's PRG met on February 7,1997, to consider reportability of the issue j
described in the February 6,1997, DR. The PRG concluded that the Oyster Creek l
commitment relative to NUREG 0737, item II.K.3.14 was contained in their April )
30,1981, letter, in which no reference was made to manually isolate the ICs upon I
receipt of a vent radiation monitor alarm. The NRC's December 18,1981,SER l
granted approval based upon the licensee's April 30,1981, letter. Therefore, the
PRG determined that Oyster Creek has not violated its item II.K.3.14 commitment
(although it appeared to be incorrectly stated in the UFSAR Section 1.9.31). In 1
addition, the PRG concluded that Oyster Creek procedures currently would lead to
manual IC isolation in the event of a tube leak based upon using a combination of
on-site radioactivity monitoring and control room indications / alarms, such as stearn
line temperatures and shelllevels and temperatures. I
c. Conclusions
The significance of removirig the problematic IC radiation monitors appeared to be
relatively low because of the distraction they provided to operators upon IC system
initiation. However, the inspector concluded that the August 1995 safety
evaluation, performed to support the December 1995 modification, was incomplete
in that it did not recognize that the IC vent radiation monitors appeared to be a
NUREG 0737 requirement. This is another dated example of failure to conduct an
adequate UFSAR review for which the licensee is currently addressing
programmatically for future safety evaluations. This additional example indicates
the need to perform reviews of other previously completed safety evaluations to
. determine whether other commitments or UFSAR items had been overlooked.
The inspector concluded that additional information is necessary to determine
, whether the licensee is in conformance with NUREG ltem II.K.3.14. Specifically,
the basis document that provided the existing UFSAR Section 1.9.31 commitment
description must be identified and reviewed. The inspector informed the licensee of
the additional information and review needed for this issue. Pending completion of
the above by the licensee and followup by the NRC, this is an unresolved item.
(URI 50-219/97-01-03)
E2J Update of Mercoid Temoerature and Pressure Switch Failures
a. Insocction Scope (37551)
The inspector reviewed the initial results of an independent laboratory analysis of
failures of recently installed Mercoid temperature switches in the stator cooling
system. The switches are Mercoid Model DA-35-804-6. Recent events concerning
these switches are also discussed in NRC Inspection Report 50-219/96-11.
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b. Observations and Findinas
On January 2,1997, the licensee initiated deviation report (DR) No.97-063 and l
material nonconformance report (MNCR) No.97-003 when initial reports from an !
independent laboratory identified several deficient conditions associated with the !
Mercoid switches the laboratory had analyzed. These switches were determined to l
be the cause of the turbine runback and manual reactor trip on October 25,1996. !
The licensee's maintenance department (l&C) determined that the thermobulb
capillary tubes were sensitive to temperature changes which could activate the
switches (NRC Report 50-219/96-11). The defective switches were replaced with a
temperature switch supplied by a different vendor (Ashcroft). The defective
switches were sent to an independent laboratory for analysis to determine root l
cause for the failures. In addition to the licensee's identification of temperature !
sensitivity, the laboratory identified t.vo other defects in the switches. The first j
s
was a failure (crack) of the actuator arm (from bourdon tube to mercury switch) tnp !
setpoint adjustment screw varnish or epoxy locking medium, which was put on the !
screws to prevent loosening. Failure of the locking medium could allow the setpoint l
adjustment screws to loosen and change the actuation setpoint of the switch. The
linkage on the old switches were more substantial and the adjustment screws did j
not use varnish or epoxy to prevent loosening. A mechanical locking tab was i
previously used. The second problem identified was a loss of fill medium l
(thermobulb and capillary tubing) due to poor brazing or soldering during
manufacture which could also cause erratic instrument switch operation.
Following notification by the laboratory, the licensee issued the DR and MNCR to
address the defective switches. The preliminary report also identified that not only
were temperature switches affected, pressure switches of similar design were
likewise affected. As a result the licensee conducted a search of the computerized
component system (GMS2) for all Mercoid switches. Seventy-three switches were
identified. None of the switches identified were used in safety related applications
and the inspector did not identify any other applications of safety concern. The !
licensee performed a walkdown of allidentified switches and identified six that were I
of the type in question and initiated action to have all six switches replaced. The i
six identified were: one in the "B" control rod drive pump low suction pressure trip, j
three in the stator cooling low pressure runback circuit (currently monitored by
additional installed instrumentation), one in the "A" main feedpump bearing lube oil
low pressure trip, and one in the emergency start circuit of the main turbine seal oil
pump. These switches will be replaced in the near future. The main feed pump
must be secured to replace the low bearing tube oil pressure switch because the j
switch cannot be isolated. The feed pump switch replacement will be performed in
conjunction with a scheduled quarterly power reduction for main steam isolation
valve full closure surveillance testing. System engineering also recommended that ;
subsequent issue of these switches be terminated and that spare switches be !
removed from the spare parts inventory. !
Due to the several deficiencies identified with the Mercoid switches, there appears
to be several contributing causes of the main turbine runback with the subsequent
manual reactor scram by control room operators. To date, only preliminary reports
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20
have been received from the independent laboratory. When the final report is
received, the licensee will make a Nuclear Network announcement to inform other
licensees of the Mercoid switch problems.
c. Conclusions
The inspector concluded that the licensee had demonstrated perseverance in their
pursuit of a root cause. They did not cease activities when switches demonstrated
a sensitivity to temperature changes, but rather sent the defective switches to an
independent laboratory for further analysis. The licensee also took prompt and
effective action to identify other switches in the plant that were of the same type
and have initiated action to replace them.
E8 Miscellaneous Engineering Issues
E8.1 (Closed) Unresolved item 50-219/95-24-01: This item concerned licensee actions
during maintenance to stator cooling multi-channel recorder. Similar issues were
subsequently identified and tracked in NRC Inspections 50-219/96-07 and 96-09.
The licensee has responded to the broader concern as presented in those reports.
In addition, specific procedural changes were implemented for station procedure
108.8, " Temporary Modification Control," to address related concerns. The
inspector reviewed the licensee's actions in response to this item. Other related
details are currently being tracked separately, in NRC open item 50-219/96-09-04.
This item is closed.
E8.2 (Closed) Licensee Event Report (96-12): Racked out breakers in 4160 Vac
switchgear d:d not meet seismic design bases. The licensee implemented effective
immediate actions to address operational concerns associated with the affected
4160 Vac breakers, and conducted a similar review for 480 Vac breakers. This
issue was previously discussed in detail in NRC Inspection 50-219/96-12 (Section
02.1). This LER is closed.
E8.3 (Closed) Licensee Event Reoort (96-14): All four steamline low pressure sensors
found below technical specification limits. NRC Inspection Report 50-219/96-12
(Section M1.4) discussed this event in detail. This LER is closed.
E8.4 (Closed) Licensee Event Reoort (96-15): Reactor water cleanup system valves may
not operate during a line break due to a non-conservative analysis. The licensee
implemented prompt and appropriate short term actions. This issue was discussed
in NRC Inspection 50-219/96-12 (Section E1.1) This LER is closed.
E8.5 (Closed) Licensee Event Reoort (97-01): Seven drywell penetrations do not meet
the requirements described in NRC Generic Letter 96-06. This issue was discussed
in NRC Inspection 50-219/96-12 (Section E1.2). This LER is closed.
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IV. PLANT SUPPORT (71707,71750,93702)
R1 Radiological Protection and Chemistry Controls
R 1.1 General Observations
During entry to and exit from the radiologically controlled area (RCA), the inspectors
verified that proper warning signs were posted, personnel entering were wearing
proper dosimetry, personnel and materials leaving were properly monitored for
radioactive contamination, and monitoring instruments were functional and in
calibration. During periodic plant tours, the inspectors verified that posted extended
Radiation Work Permits (RWP) and survey status boards were current and accurate.
They observed activities in the RCA and verified that personnel were complying
with the requirements of applicable RWPs, and that workers were aware of the I
radiological conditions in the area.
R1.2 Automatic Trio of the Auamented Offaas System /Buildina and Radioactive Airborne
Contamination Due to Subseauent Eauipment Failure
a. Inspection Scoce (71707,71750,93702)
On February 6,1997, the augmented offgas (AOG) system isolated due to a
momentary loss of power that occurred after an automobile hit a local utility pole.
Subsequently, an equipment failure resulted in radioactive airborne contamination in
the AOG building. The inspector responded to the control room following the event,
interviewed operations and radiological controls (radcon) personnel, reviewed
system drawings, and monitored the licensee's followup activities.
b. Observations and Findinas
The AOG system functioned as per design when it tripped and isolated following the
momentary power loss. Operators immediately responded to the AOG building and
found that conditions in the building appeared normal. The backup power supply
'
was available, which automatically transferred, and operators were preparing to
place AOG back in service. However, while the operators were reviewing the
associated procedure, they heard a " pop" from the "B" hydrogen detector followed
by a rush of air leakage. They also noted an increase in building radiation levels.
The operators immediately evacuated the AOG building due to the elevated radiation
levels and not being able tu isolate the leak.
Within 30 minutes of the loss of power, operators re-entered the building with
radiological controls personnel and instrument maintenance technicians. The
maintenance technician opened a recombiner hydrogen detector panel and re-
connected a section of tubing that had apparently blown off its connection within
the panel.
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When the AOG system isolates, an air purge valve automatically opens to purge the -
contents remaining in the recombiner. An associated system vent valve opens to
provide a release pathway (to the stack) of the purged volume. Both the air purge
and system vent valves are subsequently closed by individual time delay relays
(after about 15 minutes). In this case, the relay associated with the air purge valve
failed, resulting in the air valve remaining open and providing air to the recombiner
at about 30 psig. Normal operating pressure for the recombiners is 2 psig. The
increased air pressure caused the hydrogen detector's tygon tube to blow off. As a
result, the unprocesscd noble gas volume remaining in the recombiner after the
isolation (combined with the purge air) was released into the AOG building.
'
Radiation protection personnel responded to the event to assess radiological
conditions both inside and outside the building. The radiological implications were
small. The majority of the activity remained in the building, and was removed via l
the AOG building ventilation system, which utilizes a HEPA filtering system. The :
licensee postulated that a very small amount of activity may have exited the
building through exfiltration (through building crevices) during the short time that I
the ventilation system was not operating (immediately after the loss of power).
Air samples obtained by radiological controls personnel outside of the building
immediately following the event showed no activity. Particulate air samples inside
the building showed 0.1 Derived Air Concentration (DAC). No iodine was detected
inside or outside of the building. The licensee's total release calculation (estimate) l
yielded 42 mci total noble gas.
I
In responding to the event, two individuals received skin contamination (hands)
from the airborne noble gas. Both were decontaminated by decay after a short time
period.
The licensee subsequently identified the failed relay and replaced it. The tubing was
secured to the hydrogen analyzer, and the AOG system was returned to service. 1
c. Conclusions
The inspector concluded that this was not a significant event from a radiological
perspective. Radiological controls personnel responded quickly and appropriately to
the occurrence. Operations and maintenance personnel likewise responded quickly
and effectively to this event.
S1 Conduct of Security and Safeguards Activities
S1.1 General Observations
!
During routine tours, access controls were verified in accordance with the Security
Plan, security posts were properly manned, protected area gates were locked or
guarded, and isofr.cion zones were free of obstructions. Vital area access points I
were examined and verified that they were properly locked or guarded, and that
access control was in accordance with the Security Plan.
!
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V. MANAGEMENT MEETINGS (71707)
X1 Exit Meeting Summary
A verbal summary of preliminary findings was provided to the senior licensee
management on March 17,1997. During the inspection, licensee management was
periodically notified verbally of the preliminary findings by the resident inspectors.
No written inspection material was provided to the licensee during the inspection.
No proprietary information is included in this report.
X2 NRC Region i SALP Management Meeting and Plant Tour
On January 27,1997, the NRC Region i Deputy Regional Administrator and the
Region I Director, Division of Reactor Projects, toured the Oyster Creek facility,
interviewed several licensee personnel, and convened a public meeting to present
the NRC's Systematic Assessment of Licensee Performance (SALP) to senior GPUN,
Inc. management. The assessment was presented by NRC personnel, with open
discussions between the NRC and the licensee concerning SALP topics.
. . . . . . . _ . . , _ _ _ _. _ ._ _. _-. _ . _ _ _
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ATTACHMENT 1
PARTIAL LIST OF PERSONS CONTACTED
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Licensee (in alohabetical crder)
G. Busch, Manager, Regulatory Affairs ;
B. DeMerchant, Licensing Engineer, Regulatory Affairs
S. Levin, Director, Operations and Maintenance
K. Mulligan, Manager, Plant Operations
M. Roche, Director, Oyster Creek
NRC (in alohabetical order) .
!
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L. Briggs, Senior Resident inspector, RI
R. Cooper, Director, Division of Reactor Projects (DRP). RI ,
P. Eselgroth, Branch Chief, DRP, RI l
W. Kane, Deputy Region I (Rl) Administrator
S. Pindale, Resident inspector, RI l
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ATTACHMENT 2
INSPECTION PROCEDURES USED
Procedure No. Title
40500 Effectiveness of Licensee Controls in Identifying, Resolving,
and Preventing Problems
37551 Onsite Engineering
61726 Surveillance Observation
62707 Maintenance Observation
71707 Plant Operations
71750 Plant Support -
92700 Onsite Followup of Written Reports of Nonroutine Events at
Power Reactor Facilities
92901 Followup - Operations
92902 Followup - Maintenance
92903 Followup - Engineering
92904 Followup - Plant Support
93702 Onsite Event Response
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ATTACHMENT 3 ,
ITEMS OPENED AND CLOSED i
Opened
l
Number Tvoe Description
97-01-01 VIO Failure of the procedure to establish controls that the tagging
order for a hydraulic control unit was satisfactorily
accomplished (01.2).
97-01-02 URI Resolution of issues related to 10 CFR Part 21 reportability
responsibility for defective General Electric CR120AD relays -
two separate vendors and utility involved in review. (E1.2)
97-01-03 URI isolation condenser radiation monitors removed from service
via a plant modification without fully addressing continued
conformance with applicable UFSAR commitments and NRC
requirements. (E2.2)
Closed
Number Tvoe Description
95-24-01 URI Licensee actions following a defeated stator cooling system
multi-channel recorder. (E8.1)
96-12 LER Racked out breakers in 4160 Vac switchgear did not meet
seismic design bases. (E8.2)
96-13 LER Motor control center DC-2 did not meet seismic design bases.
(M8.1)
96-14 LER All four main steamline low pressure sensors found below .
technical specification limits. (E8.3) l
96-15 LER Reactor water cleanup system valves may not operate during a l
line break due to a non-conservative analysis. (E8.4)
97-01 LER Seven drywell penetrations do not meet the requirements
described in NRC Generic Letter 96-06. (E8.5)
I