ML19327A866
| ML19327A866 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 09/29/1989 |
| From: | Mendonca M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | |
| Shared Package | |
| ML19327A864 | List: |
| References | |
| 50-344-89-20, NUDOCS 8910180318 | |
| Download: ML19327A866 (19) | |
See also: IR 05000344/1989020
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U. S. NUCLEAR REGULATORY COMMISSION
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REGION V
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Report No. .
50-344/89-20
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Docket No.
50-344
License No.-
HPF-1
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Licensee:
Portland General Electric Company
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121 S.W. Salmon Street,.TB-17
Portland, OR 97204
Facility Nsme: Trojan
' Inspection at: Rainier, Oregon'
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Inspection conducted: ~ July 30,1989 - September 9, 1989
' Inspectors:
R. C. Barr
Senior Resident Inspector
J. F. Melfi
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Resident Inspector
Approved By:
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M. M. Mendonca, Chief-
Date Signed
Reactor Projects Section 1
Summary:
Inspection on July 30 - September 9,1989 (Report 50-344/89-20)
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Routine inspection of operational safety verification,
Areas Inspected:
maintenance surveillance, event follow-up, system engineering, and open item
follow-up.
Inspection procedures 30702, 30703, 61726, 62703, 71707, 92700,
~92701, and 93702 were used as guidance during the conduct of the inspection.
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Results
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This inspection identified three apparent violations of regulatery
Weaknesses included (1) failure to implement adequate
requirements.
administrative controls to ensure compliance with technical. specification
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surveillance requirements; and (2) failure to acceptably store quality records
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-in a timely manner (non-cited violation).
8910180318 890929
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Additionally, throughout this inspection period there were numerous repetitive
failures of electronic safety equipment.
The failures appear to be due to a
combination of component failure, poor workmanship, and inadequate quality
The inability to arrest these repetitive equipment failures
verification.
appear to be due in part to management's willingness to continue operation
with lingering deficiencies.
Finally, an unresolved item relating ~ to Final Safety Analysis Report seismic
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design analysis was identified.
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DETAILS-
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Persons Contacted
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D.-W. Cockfield, Vice President, Nuclear
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- C, P Yundt, Plant General. Manager
'*T. D. Walt, General Manager, Technical Functions
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R. M. Nelson, Manager, Nuclear Safety and Regulation Department
A. N. Roller, Manager, Nuclear Plant Engineering
C. K. Seaman, Manager, Nuclear Quality Assurance
- D. W. Swan, Manager, Technical Services
- M. J. Singh, Manager, Plant Modifications
- J. D. Reid, Manager, Quality Support Services
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- J. W. Lentsch, Manager, Personnel Protection
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J. M. Anderson, Manager, Material Services
- R. E. Susee, Manager, Work Planning and Control
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- D. L. Bennett, Branch Manager, Maintenance
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J.
. Mody, Branch Manager, Plant Systems Engineering
D. L. Nordstrom, Branch Manager, Quality Operations
- J. P. Fischer, PM/EA Branch Manager
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T. O. Meek, Branch Manager, Radiation Protection
R. N. Prewit, Supervisor, Quality Systems
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D. F. Levin, Supervisor, Plant Modifications
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- E.- A. Curtis, Procurement Supervisor
- R. L Russell, Operations Supervisor
J. C. Heitzman, Acting Assistant Operations Supervisor
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D. L.-Bennett, Maintenance Supervisor
N. A. Regoli, Instrument and Control Supervisor
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J. A. Benjamin,' Supervisor, Quality Audits
J. D. Guberski, Nuclear Safety and Regulation Department Engineer
- W. J. Williams, Compliance Engineer
The inspectors also interviewed and talked with other licensee employees
during the course of the inspection.
These included shift supervisors,
reactor and auxiliary operators, maintenance personnel, plant technicians
and engineers, and quality assurance personnel.
- Denotes those attending the exit interview.
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2.
Plant Status
On July 30, 1989, the facility was in Mode 3, Hot Standby, at normal
operating temperature and pressure with an investigation in progress as
to the cause of blown fuses for rod D-4 that had dropped from 105 steps
withdrawn on July 27, 1989.
At 5:22 pm, on July 31, 1989, after
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determining that the rod D-4 blown fuses resulted from low resistance
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-grounds in containment electrical penetration NZ13 and correcting the
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problem, the reactor was restarted.
At 6:28 pm, the reactor was again
shutdown when control rod K-14 misaligned by twenty-four steps from the
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remainder of the control rods in its control bank.
At 5:22 am, August 1,
1989, after determining that rod K-14 misalignment was due to binding,
most likely caused by a small transient foreign particle and exercising
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rod K-14 successfully, the reactor was restarted.
From August 1 through
August 5, 1989, the reactor was shifted between Mode 1 and 2 to evaluate-
main turbine problems.- On August 5, 1989, ascent to full power began.
On August 9,.1989, while at 50% reactor power, a trip on overtemperature
delta temperature (OT delta T) automatically shutdown the reactor.
At
_ 5:23 pm,-August 14, 1989, after concluding the automatic reactor shutdown
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resulted from an intermittent OT delta T signal, whose exact cause could
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not be determined, and the simultaneous performance of a surveillance on
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another channel of OT delta T, the reactur was restarted. On September'
- 2, 1989, 100% power was momentarily achieved then power was reduced-to
99% when an overpower delta temperature (OP delta T) rod block occurred.
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The inspection period concluded with the reactor at 99% power with an
evaluation in progress as to the cause of both OP and OT delta
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temperature rod blocks.
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3;
Safety Verification (71707)
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Operational Safety Verification
During this inspection period, the inspectors observed and examined
activities to verify the operational safety of the licensee's facility.
The observations and examinations of those activities were conducted on a
daily, weekly or biweekly basis.
Daily the. inspectors observed control room activities to verify _the
licensee's adherence to limiting conditions for_ operation as prescribed
in the facility Technical Specifications,
l.ogs, instrumentation,
recorder traces, and other operational records were examined to obtain
information on plant conditions, trends, and compliance with regulations.
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- On occasions when a shift turnover was la progress, the turnover of
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information on plant status was observed to determine that pertinent
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information was relayed to the oncoming shift personnel.
Each week the inspectors toured the accessible areas of the facility to
observe the following items:
(a) General plant and equipment conditions.
(b) Maintenance requests and repairs.
(c) Fire hazards and fire fighting equipment.
(d) Ignition sources and flammable material control.
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(e) Conduct-of activities in accordance with the licensee's
administrative controls and approved procedures.
(f) Interiors of electrical and control panels.
(g) Implementation of the licensee's physical security plan.
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(h) Radiation protection controls.
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(i) Plant housekeeping and cleanliness.
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(j) Radioactive waste systems.
(k) Proper storage of compressed gas bottles.
Weekly, the inspectors examined the licensee's equipment clearance
control with respect to removal of equipment from service to determine
that the licensee complied with technical specification limiting
conditions for operation. Active clearances were spot-checked to ensure
that their issuance was consistent with plant status and maintenance
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evolutions._ Logs of jumpers, bypasses, c.aution and test tags were -
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examined by the' inspectors.
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Each week the inspectors conversed with operators in the control room,
and with other plant personnel.
The discussions centered on pertinent
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topics relating to general plant conditions, procedures, security,
training and other topics related to in progress work activities.
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The inspectors examined the licensee's nonconformance reports (NCRs) to
confirm that deficiencies were identified and tracked by the system.
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-Identified nonconformances were being tracked and followed to the
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completion of corrective action.
Routine inspections of the licensee's physical security program were
performed in the areas of access control, organization and staffing, and
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detection and assessment systems.
The inspectors observed the access
control measures used at the entrance to the protected area, verified the
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integrity of. portions of the protected area barrier and vital area
barriers, and observed in several instances the implementation of
compensatory measures upon breach of vital area barriers.
Portions of
the isolation zone were verified to be free of obstructions.
Functioning
of central and secondary alarm stations (including the use of CCTV
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monitors) was observed.
On a sampling basis, the inspectors verified
that the required minimum number of armed guards.and individuals
authorized to direct security activities were on site.
The inspectors conducted routine inspections of selected activities of
the licensee's radiological protection program.
A sampling of radiation
work permits (RWP) was reviewed for completeness and adequacy of
information.
During the course of inspection activities and periodic
-tours of plant areas, the inspectors verified proper use of personnel
monitoring equipment, observed individuals leaving the radiation
controlled area and signing out on appropriate RWP's and observed the
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posting of r6diation areas and contaminated areas.
Pssted radiation
levels at' locations within the fuel and auxiliary buildings were verified
using both NRC and licensee portable survey meters.
The involvement of
health physics supervisors and engineers and their cwareness of
significant plant activi+ies m assessed through conversations and
reviews of RWP sign-in tecm as.
The inspectors verified the operability of selected engineered safety
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features.
This was-done by direct visual verification of the correct
position of valves, availability of power, cooling water supply, system
integrity and general condition of equipment, as applicable.
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Verification of Operator Certification of Medical Examination
The inspectors evaluated the licensee's administrative system for
assuring that medical examination requirements for licensed operators are
acceptably implemented.
The inspection included comparing licensed
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operator medical records against the licensee's " Certification of Medical
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Examination by Facility Licensee"-NRC Form 396.
The inspectors found the
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licensce's administrative controls were effective to ensure licensed
operators receive a medical examination every two years.
The licensee
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training organization maintains the dates-when each licensed operator
requires a medical examination and informs the licensed operator when the
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examination is required. The NRC Form 396s are maintained in the
licensee document storage vault and eventually microfiched.
The
inspectors also reviewed twenty-eight of the forty-six licensed
operator's NRC Form 396s to assess whether or not medical examination
were current.
No deficiencies were noted.
No violations or deviations were identified.
4.
Maintenance (62703)
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The inspector observed corrective maintenance on a rod control drive
mechanism. The licensee was performing Periodic Operating Test (POT)
15-1, " Control Rod Drive System Full-Length Rod Movement Verification,"
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on August 31, 1969 when it was noted that the Shutdown Banks C/0 would
not-insert.
This test is performed monthly to verify the proper
operation of the full-length rod clusters, drive mechanisms, and the
associated control and indication circuits.
The rods and associated step
counters would give only outward motion whether selected to drive in or
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out.
The Control Operator informed the Shift Supervisor and
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Instrumentation and Control, and entered into the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> action
statement of Technical Specification 3.1.3.1.
Internal Event Report (ER)
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89-147 was issued on this event.
The licensee discussed this problem with the Nuclear Steam System
Supplier, Westinghouse.
Three likely causes for the failure of the rods
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not to step in were identified:
Card A-701 (Pulse Shaper) failure, Card
A-307 (Logic) failure, or the input / output relay (K-17/K-18) failure.
The licensee initiated Maintenance Request (MR) 89-8373 to troubleshoot
the problem. Work instructions were included with the MR; the MR was
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reviewed by Quality Control; and Quality Control hold points were
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established.
During the-conduct of the maintenance, the MR was refined
several times to further categorize and isolate the failure. Quality
Control involvement was evident each time.
The licensee determined that
the logic card failed and replaced the card.
The inspector verified the meters used in the conduct of maintenance were
calibrated.
He noted that the logic card came in a bag which said
Non-Quality Related.
Independently, the licensee's Quality Control
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Inspector came to the same conclusion, wrote a Non Conformance Report
(NCR)89-415 to document the Non Quality Related indication and wrote a
Non Conforming Activity Report (NCAR) P89-397 as to how this part should
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have been restored.
The inspectors will follow up on this as a course of
routine inspection since a similar event happened previously as noted in
Inspection Report 50-344/89-17.
With the facility in Mode 1, the inspector observed the return to service
and operation of the Rod Control System.
Plant licensed operators noted
'the step counter position, digital rod position indication (DRPI), and
then exercised control rods.
The inspector asked the control operator if
he was sure that the Shutdown Bank Rods were at 226 steps since technical specification 3.1.5.4 requires that Shutdown Banks be greater than 225
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steps in Modes 1 or 2.. The operator appeared not to be familiar with
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that-technical specification requirement.
By actual DRPI indications
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(228~ steps), the rods.were greater than 225 steps, therefore, the
requirements of the technical-specification were met.
Through routine
followup, the inspectors will continue to evaluate operator knowledge of
Technical Specifications.
No violations or deviations were identified,
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5.
Surveillance (61726)
Reactor Trip (RTB) Breaker Position Verification
On July 26, 1989, the licensee conducted an-inspection of the reactor
trip breakers and found the right hand side (RHS) latch was not fully
engaged.
An internal licensee event report (ER89-113) was written. As
part of this event report, the licensee Quality Assurance organization
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recommended the corrective actions of training and posting operating
instructions on the inside panel of the breaker cubicle door.
These
corrective actions were not implemented.
This insensitivity by plant
management to this important issue may have contributed to event
recurrence.
On August-1, 1989, a maintenance craftsman, while training
another craftsman on breaker operation, noted the RHS latch was not fully
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latched. The previous event report was revised to incorporate this
second event.
As a result of the second incident of the Reactor Trip
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Breakers (RTB) not being fully latched, the licensee implemented a
program to inspect the RTB's every week to ensure proper latch engagement
and that RTB operation would only be performed by a trained electrician.
Paragraph 8 further discusses the latch design function of the RTB's.
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Subsequent to each event, the breaker RHS latch was correctly latched to
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assure RTB design function.
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The inspector observed the licensee perform one of the weekly inspections
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of the RTBs. The technician told the shif t supervisor that he would be
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opening the RTB cabinets for inspection.
The technician followed the
instructions on MR 89-7631. The inspector reviewed the previous data
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sheets, and noted that the RHS latch of RTB A was bent.
This was not
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considered by the licensee to be an operability issue.
Core Thermal Power Evaluation
The inspector reviewed Plant Operating Test (POT) 22-1, " Heat Balance
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Calibration," for technical adequacy and examined calculations performed
by this procedure. The licensee performs a core thermal power
calculation (calorimetric) daily when they are above 15% power by POT
22-1.
This procedure is used daily to adjust or verify the accuracy of
the Power Range Nuclear Instrumentation setpoints (Technical
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Specification Surveillance 4.3.1.1) which inputs into the Reactor
Protection System.
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The inspector reviewed the POT 22-1 data sheets, and determined that the
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data and results appeared reasonable by performing a rough calculation
that confirmed the actual value obtained by the licensee for the
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calculation of total core power.
The inspector also observed a
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calorimetric in progress.
The procedure requires-the plant to be.at
steady-state operation prior to obtaining calorimetric data. The:
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parameters of feed water flow, water levels, steam generator blowdown
flow, and primary pressure were not changed appreciably during the
calorimetric.
On August 14, 1989, the. inspector reviewed the last 30 calorimetric data
sheets.
During the review, the inspector determined that some of the
data sheets were not in the vault.
The data sheets from March 29, 1989
through April 5, 1989 were determined to be with the system engineer who
reviews the data sheets for system performance. The inspector questioned
the appropriateness of having QA records for that length of time.
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inspector subsegaently determined that the licensee's Administrative
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Order (AO) 7-1, " Plant Records" required QA records be kept for only 120
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days without being installed in an approved facility or cabinet.
The
-system engineer generated Non-Conforming Activity Report (NCAR) P89-368M.
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Because this licensee corrective action was prompt and appropriate, this
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violation was identified to the licensee as an non-cited Severity Level V
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violation.
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The inspector verified that Steam Generator Pressure, Delta Temperature
indications, and Nuclear Instruments all were in calibration.
The
inspector identified that the Feedwater Flow indicators used in the
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calorimetric were not always meeting their calibration frequency.
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inspector determined that the plant had started up and was above-15%
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power with two feedwater flow instruments that did not meet their
calibration frequency.
Further investigation revealed that these
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feedwater flow indicators were not required by the Technical
Specifications on the Trojan Surveillance Schedule (TSS). The inspectors
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. questioned the appropriateness of this designation, since the calibration
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of this instrument is used to determine secondary heat balance.
The
licensee agreed with the inspectors, changed the designation, and
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committed to review their instrumentation list to verify that all the
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instruments used were appropriately designated.
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The technical spec:ification designations (on the TSS) used by the
licensee are:
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Priority Definition
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1
Required directly by.the tech specs
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Indirectly required by the tech specs, implied by the tech
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specs, or instrument used to verify tech spec operability.
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Required by some commitment that PGE has made in writing,
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4
Not required by tech specs, but controlled as if it were.
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Not required.
The inspector determined that the priority codes were either initially
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assigned when the TSS was placed in service, or were input into the TSS
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by the I&C Supervisor (s) if discrepancies were identified. The licensee
should evaluate the appropriateness of this review technique.
The inspector had concerns about the licensee's computer program
calculations.
These concerns can be listed as follows:
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(1) The licensee does not check the secondary heat balance with a
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primary heat-balance, to see if the loops indicate about the same
power. The inspector's calculations indicate that the maximum
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difference between the loops is almost 1% of total power.
(2)' The licensee does not explicitly use'tise venturi equation for
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feedwater flow.
The feedwater flow. equation is~ basically constants
times the square root of the differential pressure across the f. low
element.
These constants are slightly different for each locp.
The.
licensee uses an average of the four loop differential pressures. to
enter into their equation.
The secondary system flowrate determined
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by the licensee is not mathematically the same as doing the
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caulculation on a per loop basis, although the results are close.
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(3) The licensee also uses a value for the clean case of a venturi.
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Also, the flow to each loop can change from cycle to cycle, because
of condenser tube fouling and steam generator tube plugging.
This
would not be reflected in the licensee's calculation.
(4) The licensee calorimetric does not individually account for CVCS
makeup and letdown effects, Reactor Coolant Pump Heat, or insulation ~
losses.
These are basically assumed as constants and lumped
together, and can be deduced from values in the data sheets.
Since
the CVCS conditions may vary, small errors'can be introduced.
The
licensee's technique has no adverse impact on safety.
The NRC has-developed their own computer program which can generate a
heat balance (Refer to NUREG-1167); and does account for most of these
phenomena.
The inspector concluded overall that the licensee's
calculations were acceptable, however improvements could be' made by the
licensee to more accurately perform the heat balance calculation.
The licensee's Quality Operations (QO) department was also evaluating the
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calorimetric concurrently with the NRC inspector.
The QO inspector had a
question about the validation and verification of the licensee's computer
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programs.
The licensee uses two procedures to verify a computer program,
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Nuclear Division Procedure (NDP) 200-4, " Quality-Related Calculations"
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and NDP 200-5, " Quality-Related Computer Programs".
The Q0 inspector
initiated NCARs on how computer programs are validated.
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The inspector also had concerns about how the program was validated.
The
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licensee calorimetric program is a LOTUS 123 program.
It is difficult to
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verify a LOTUS 123 program looking at the program listing, but the
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inspector did verify parts of the program with the licensee's help.
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inspector will follow up on the licensee's computer program validation
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and verification.
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One violation was identified.
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6.
Plant Startup from Refueling and Event Follow-up (71707, 92700, 93702)
From~ July 26, 1989, at 10:18 am, until September 2, 1989, at 3:35 am, low
power physics and ascent to 100% reactor power were conducted.
The
following subsections document inspection activities and major events
that occurred during the startup from the 1989 Refueling Outage.
Dropped Control Rod 0-4
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At 8:40 pm on July 27, 1989, with the reactor critical, and low power
physics testing in progress, control rod 0-4 dropped to the bottom of the
core from 105 steps withdrawn.
No anomalous or unusual indications were
noted during or after the rod dropped.
The reactor was immediately
shutdown, shifted to Mode 3 and internal event report 89-112 initiated.
At 9:33 pm, the licensee identified that the lift coil power fuse had
blown.
At 9:35 pm, the fuse was replaced and control rod D-4 withdrawn
and inserted (exercised) several times to verify operability.
At 10:06
am, the licensee notitied NRC of the event via the emergency notification
system. .At 4:05 am on July 28, 1989, subsequent to rod exercising and
prior to restarting the reactor, control rod D-4 lift coil fuse was found
blown for a second time.
The licensee developed a troubleshooting
strategy to identify the cause of the failure of the lift coil fuses.
. Grounds were identified on the power supply cabling.
The grounds were
isolated to a module within containment electrical penetration NZ13, the
electrical penetration for the lift coil power leads.
Additional
investigation identified that most of the wires within that. module of
containment electrical penetration NZ13 had ground indications.
Further
investigation disclosed that during the 1989 Refueling Outage, when the
licensee was evaluating the cause of 14 and 16 gauge wires being easily
pulled from containment electrical penetration modules (reported in NRC
Inspection Reports 50-344/89-10 and 89-16 and Licensee Event Report
89-10), module X of.NZ13 remained out of.the containment electrical
penetration exposed to air, for approximately six weeks. Because the
penetration module was exposed to air, the licensee concluded the grounds
resulted from moisture intrusion into the module.
The licensee had
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previously experienced grounding problems when containment penetration
modules were left exposed to open air during initial construction.
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As corrective action, the licensee disconnected the grounded wires from
module A of NZ13 and reconnected the wires to spare connections in other
modules.
The licensee also plans to consider maintenance procedure
changes to assure that similar modules do not experience similar
problems.
The licensee continues to evaluate the integrity of
containment electrical penetrations and has a long term action to replace
the Bunker-Ramo electrical penetration during the 1990 Refueling Outage.
Misaligned Control Rod K-14
On July 31, 1989, at 5:22 pm, after resolution of the blown fuses
associated with rod D-4, the reactor was restarted.
At 6:14 pm, while
continuously withdrawing control bank B rods, rod K-14 stopped moving out
at 180 steps while the remainder of the control bank rods stepped out to
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204 steps.
The control operators did not identify any abnormal
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conditions other than.the rod misalignment.
Rod withdrawal was
. immediately stopped when the control operator recognized the rod, K-14 -
was misaligned.
Subsequently, the operators determined the rod could not
- be withdrawn but could be inserted. The reactor was shutdown and an
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internal event report written.
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Trojan Technical Specification (T.T.S.) 3.1.3.1. (applicability Modes 1
and 2) states "all rods shall be OPERABLE and positioned within + or - 12
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steps (indicated position) of the group step counter demand position."
When outside this condition, as was the case for this event, the
technical specification action requires'" SHUTDOWN MARGIN be determined.to
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be within'the requirements of T.T.S. c. 1.1.1 within one hour of discovery
and be in HOT STANDBY within six hows." Shutdown Margin was verified
and HOT STANDBY attained within 14 minutes of the rod being recognized as
stuck.
The licensee. informed NRC of the event via the ENS at 8:12 pm and
informed the NRC resident that evening.
During the discussion between
,
the Resident and Duty Plant General Manager (DPGM), the Resident asked
!
the DPGM if a rod deviation alarm annunciated. The Resident Inspector
'
was concerned that the rods were out of position by twice that allowed by_
T.T.S. 3.1.1.1 and a deviation alarm should have alerted the control
' h
operator.to stop continuous rod withdrawal at a rod deviation of 12
s
k.
steps.
The DPGM told the Resident he would find out if the alarm was
!
annunciated.
The licensee, in conjunction with the reactor vendor (Westinghouse),
cor.:1uded that the most likely cause of rod K-14 being out of alignment
>
and unable to be withdrawn was a foreign particle in the control rod
mechanism.
Subsequently, control rod K-14 was fully withdrawn and
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inserted exhibiting no signs of mechanical binding. At 5:22 am, August
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1, 1989, the licensee conducted a reactor startup.
-At 6:30 am, August 1, 1989, the resident inspectors, as follow-up
inspection, discussed rod K-14 misalignment with the Shift Supervisor,
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Instrument and Control (I&C) Supervisor, and the Duty Plant General
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Manager.
Again the inspectors questioned whether or not the rod
deviation alarm annunciated.
To their knowledge the alarm had not
annunciated; however, the DPGM stated that had not been verified.
The
f
FSAR and station training manuals indicate the rod deviation alarm should
H
have annunciated when K-14 was misaligned.
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The inspectors, at 9:20 am, . August 1,1989, discussed the operation of
the rod deviation monitor with the reactor engineer.
He explained that
.t
the plant computer (P-250) generates the alarm signal that is transmitted
'
to the control board annunciator. The reactor engineer also noted that
each time the computer is restarted (rebooted) certain data, such as rod
He noted that he had just rebooted the
position, has to be re-entered.
computer that morning and the deviation monitor appeared to be operating.
Subsequently, the reactor engineer recognized the computer was not
accepting rod position update data and at 12:00 pm on August 1, 1989, the
rod deviation program was declared inoperable.
Later, the licensee
determined the rod deviation monitor program was not accepting the input
rod data due to a change from partial length to full length control rods,
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corrected the program and declared the Rod Deviation Monitor Program
The inspectors again reviewed the D-4 rod drop event of July 17, 1989,
and noted that the rod-deviation alarm was not received when D-4 dropped.
During this event, the licensee operators had failed to recognize the rod
deviation alarm should have annunciated. The inspectors reviewed records
and concluded that the rod deviation monitor was inoperable from at least
July-16, 1989, through August 1, 1989. With the Rod Deviation Monitor
inoperable T.S.S. 4.1.3.1 requires rod position be verified once every
four hours, however, rod position was being verified once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
This is_an apparent violation (50-344/89-20-01).
The inspectors next attempted to identify licensee requirements to verify
operability of-the rod deviation monitor.
None could be identified.
The
inspectors concluded the root cause of the apparent violation was that no
administrative requirement existed to verify the rod deviation monitor
Additionally, the inspectors, through discussions with
licensed operators, identified a weakness in operator knowledge on the
purpose and operation of the rod deviation monitor.
The licensee
training manual provides a description of the Monitor.
At the exit the
licensee committed to evaluate the operator training program for adequacy
concerning the Rod Deviation Monitor and establish an administrative-
control to verify Rod Deviation Monitor operability.
Reactor Startup Observations of August 14, 1989
During the reactor restart begun at 5:53 pm, on August 14, 1989, while
control rod Shutdown Bank C was being withdrawn, a computer alarm on
control rod deviation was received.
Operators responded rapidly by
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stopping control rod withdrawal and taking the actions specified in the
associated annuriciator response guide.
The operators noted that the
annunciator' response guide was not up-to-date, in that it called for use
of a deleted procedure, Off Normal Instruction (ONI) 2-7, " Reactor
Control or Rod Position Indication Malfunction." Operators were familiar
with the current procedure, Operating Instruction (01) 2-4, " Control Rod
Drive and Position Indication," and used that procedure. The Shift
Supervisor (SS) initiated a change to the annunciator response guide to
,
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correct this deficiency.
This problem was also the subject of a previous
licensee critique.
Licensee followup determined that the findings from
the previous critique had not been corrected.
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The operators determined that the problem was related to the plant
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computer and that the rod deviation alarm was inoperable.
The SS
requested clarification of the Technical Specification requirement for
inoperable control rod deviation alarms from the Duty Plant General
Manager.
The guidance indicated that an increased surveillance frequency
of rod position indication would compensate for a nonfunctioning alarm.
,:
Rod position verification was increased from 12 to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> and repairs of
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the computer were delayed until completion of this Shutdown Bank C rod
movement in order to avoid potential transients during maintenance.
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Source Range Channel N32 Failures
Two channels of Source Rar.ge nuclear instruments monitor reactor power.
These instruments normally provide reactor protection features during
shutdown and startup conditions.
Previous to the 1989 Refueling Outage,
the Source Range nuclear instruments had exhibited erratic reliability,
,.
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and during previous refueling outages cabling had been completely
replaced.
During the 1989 Refueling Outage, source range channel N32
failed in excess of ten times.
The failures were generally intermittent
random failures that would recur approximately every five minutes with
{
-the indicated count rate going to zero.
On each occasion a maintenance
request was written and the failure evaluated by the Instrument and
)
Control (I&C) group.
On each occasion after troubleshooting, that
generallyconsistedofsomeoftheconnectorsbeingverifiedtightand/or
clean, some current / voltage verification and integrated circuit board
,
replacement, the instrument was returned to service, a surveillance
successfully performed and the instrument declared operable.
Thereafter,
,
the instrument operated for several days to several weeks and failed
'
again .. On July 29, 1989, at 9:30 am, channel N32 failed again. -The
licensee determined that the cause of that failure was a pre-amp
connector not being fully engaged.
For the remainder of this inspection
period N-32 operated without failure.
The inspectors observed work and troubleshooting on the Source Range
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instrument several times during this inspection period.
Generally, the
troubleshooting plans were not comprehensive plans that verified ALL
connectors were properly made and that incorporate long term signal
monitoring.
Licensee supervisor and management attention to the failure
of N32 should be increased to assure a comprehensive plan to exaulne and
monitor source range channel N32.
Reactor Trip on Over Temperature Delta Temperature (OT delta T)
On August 9,1989, with the plant operating at approximately 50% power, a
reactor trip occurred from the Over Temperature delta Temperature (OT
delta T) protection circuitry.
The OT delta T reactor trip is to provide
core protection from a Departure from Nucleate Boiling (DNB).
To provide
this protection, a trip setpoint is continuously calculated by a function
. generator with inputs from the RCS average temperature (Tave), the RCS
hot leg and cold leg temperature difference (delta T), another function
generated with neutron flux as an input, and pressurizer pressure.
The
OT delta T calculated setpoint is compared to the actual delta
temperature, and if the setpoint is less than actual delta T, a trip
signal is generated. The OT delta T trip signal is a 2 out of 4 logic,
with four channels each calculating a margin to trip.
Prior to and at
the time of the trip, the nuclear instruments to channel 3 were being
reset, based on data provided by the reactor engineer.
To enter this
data, the licensee was performing Periodic Instrumentation and Control
Test (PICT) 6-3, and PICT 11-1 for loop 3.
Due to the work performed,
the bistables to this channel were placed in the tripped state.
This
reduced tne logic to trip from 2 out of 4 to 1 out of 3.
At 12:20 pm, on
August 9, 1989, the licensee received a signal to trip from another
channel, which caused a reactor trip.
Subsequent investigation indicated
that the other trip signal came from channel 4, based on the sequence of
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events recorder which shows that channel 4 of OT delta T came in first,
and that the OT delta T re: order happened to be set to record channel 4
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and the recorder paper shows a spike at the time of the reactor trip.
The trip signal on the sequence of events recorder was shown in for 25
cycles (approximately 1/2 second).
The inspector arrived in the control
room 3 minutes after the reactor trip and observed the reactor recovery.
The licensee, as a result of the reactor trip, initiated an internal
event report and generated a plan of action to determine the cause of the
trip.
One of the corrective actions replaced three modules in the OT
t
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delta T circuit:
the summator, Tave lead / lag module, and the trip
bistable comparator.
These OT delta T modules in the protection system
,
at the time of the trip were bench tested and thermally cycled after
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being removed to determine if they would fail.
No failures were found.
The licensee also installed recorders on all 4 loops of the OT delta T
4
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circuit' to monitor and record the input into OT delta T.
Subsequent
investigation of events preceding the trip revealed that the P-250
.
computer received alarms for channel 4 OT delta T going high and low
approximately nine hours before the reactor trip.
The OT delta T alarms
on the computer were discussed by the shift supervisors at control room
turnover but no actions had been taken by the time of the trip.
The
licensee replaced the modules, and began a power ascension.
After
ascending in power, the plant again received computer alarms.
The plant
also began to have the rod stop bistable annunciate intermittently for a
duration of 1/2 second from the OT delta T channel 4 protecting circuit,
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which had not been previously seen.
After receiving some bistable light
flashes, the licensee also monitored the OT delta T indicators
continually with a video camera, and recorded the intermittent OT delta T
,
- setpoint anomalies on loop 4.
The licensee continued to receive rod
block bistable flashes until August 28, 1989, when a measuring tape
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dropped by a civil engineer on top of the reactor protection cabinet
containing OT delta T circuitry caused a series of OT delta T rod block
bistables to flash.
Observing the engineer on top of the cabinet, it
,
became evident the rod block bistable trips were generated by a loose
connection. The licensee investigated and found a loose connection on
the recently replaced OT delta T lead / lag module.
After replacing that
module, channel 4 OT delta T has not generated any rod blocks. This bad
connection probably did not explain the reactor trip since it was
generated by a lead lag module that was not in the circuit at the time of
f
the trip. 'Also computer alarms on OT delta T and OT delta T setpoint
generator have been generated since the replacement of the module.
'
!
The inspectors noted that the OT delta T indicated setpoint is about 113%
for loop 4, with the other loops indicated setpoint at 120-122%.
The
setpoint also appears to have significant variation.
The licensee
determined that the setpoint being generated in loop 4 was accurate since
loop 4 T-hot is reading about 4.5 degrees F. higher than the other loops.
The thermocouple detectors for the RCS temperature were verified to be in
calibration by the licensee.
The increased temperature does not appear
to account for the difference in setpoint seen.
The inspectors through
manual calculation, attempted to verify the lower (actual seen) setpoint;
however, the temperature difference appeared not to explain the total
setpoint difference.
The licensee committed to provide the inspectors
additional information prior to considering this issue resolved.
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The licensee did not determine the cause of the intermittent OT delta T
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trip signal; however, prior to restart an attempt was made to duplicate
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the signal.
Of the possible causes listed by the licensee for the
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reactor trip, the only cause not dismissed by the licensee was the
1
lowering of an OT delta T constant to meet a new Technical Specification
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amendment setpint requirement.
This could result in the peaks of
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channel noise being closer to the trip setpoint.
However, at 50% power
,
where the reactor trip occurred, the OT delta T setpoint was over 100%
~
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more than actual delta T.
This lowering of the setpoint does not appear
to the . inspectors to have had any affect on why the reactor tripped.
The
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licensee investigation was still continuing at the end of the inspection.
The performance of the OT delta T reactor protection circuitry provides
additional evidence that work practices in the I&C area should be closely
evaluated.
One violation was identified.
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7.
Follow-up of Licensee Event Reports [LERs] (92700, 90712)
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LER 89-06, Revision 1. (Closed), " Steam Dump Valve Failure Caused
<'
'
Engineered Safety Feature Actuation." This revised LER provided
additional information (causes, corrective actions and commitments) on
the April 6,1989, events of erratic steam dump valve 507A operation, the
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failure of an instrument air line and the inability to manually drive
bank A shutdown control rods.
.,
The licensee concluded that the erratic operation of the steam dump valve
PCV 507A was due to a shorted solenoid caused by a broken wire followed
by a pneumatic valve operator air line for PCV 507A.
The air line failed
due to low cycle fatigue.
The failure of A shutdown control rod bank to
manually drive was determined to be due to a blown fuse on the power
supply A phase for the Control Rod Drive Mechanism (CRDM) stationary
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gripper.
Licensee corrective actions for each of these items were
acceptable.
l,
The inspectors observed the retesting and operation of the steam dumps
'
subsequent to the extensive maintenance performed on the steam dumps
during the outage.
The steam dumps operated per design.
The inspectors
!
observed proper operation of the rod control system immediately
ii
subsequent to the replacement of the blown fuse.
Since re-energization
of the rod control system in preparation for recovery from the 1989
W
Refueling Outage, numerous deficiencies, such as additional fuses
blowing, a dropped rod, and a misaligned rod, have occurred.
Even though
t:
replacing the immediate deficiency of the blown fuse solved the inability
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of the A shutdown bank to drive on April 6,1989, the reliability of the
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rod control system had been poor.
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LER 89-08, Revision 1, (Cinsed), " Spent Fuel Pool Exhaust System
Inoperable While Moving Fuel." This LER revised the previously reported
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failure to maintain the techiiTcal specification required negative
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pressure in the Spent Fuel Pool Exhaust System during refueling
operation.
The revision supplements the previous report by deferring
from August 1 to November 30, 1989, the corrective action to identify
through testing ventilation system lineups required to ensure AB-4 (Spent
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Fuel Pool) ventilation system operability.
This change is acceptable
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because refueling activities are not scheduled until April 1990.
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LER 89-13. Revision 0, (Closed), " Cognitive Personnel Errors in
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Directing Work Resulted in an Inadvertent Reactor Trip Signal While
Shutdown.__" This LER reported a reactor trip signal on to-to steam
generator water level (SGWL) as a result of a Department Manager, without
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conferring with shift management, directing an instrument technician to
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remove temporarily installed jumpers that inserted a false (dummy) SGWL
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signal into the pro cction system. When the jumpers were removed, the
,
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actual low level in steam generators monitored by the reactor protection
system and resulted in an engineer safety features (reactor trip breaker)
!
actuation.
L
The licensee attributed the causes of the event to personnel bypassing
normal work control system practices and inadequate access controls to
.
the protection racks.
Licensee corrective actions included disciplinary
action, training, issuance of a plant wide memorandum that emphasized
procedure compliance and a commitment to evaluate positive control over
.
the reactor protection system racks.
l
The inspectors attended the licensee critique that discussed the event,
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and discussed the event with personnel involved and with Plant Managers.
The inspectors noted that uncontrolled access to the reactor protection
,
racks had been a previous concern and resulted in previous events.
Additionally, since this event, an engineer was found to be walking on
the top of the protection racks without being authorized.
As corrective
'
action, the licensee plans to implement positive controls over access to
the reactor protection racks by December 29, 1989. The inspectors will
continue to evaluate access to reactor protection system equipment during
routine inspections.
'
LER 89-16. Revision 0, (Closed), " Inadequate Procedure and Personnel
Errors Result in Power Operation with the Containment Recirculation Sump
Protective Screen Not Installed." This LER reported containment
recirculation sump deficiencies (missing top screen, screen gaps around
penetrating piping) and inadequacies in containment recirculation sump
inspections and inspection procedures.
The details of these deficiencies
are described in NRC Inspection Report 50-344/89-19.
Additionally,
licensee commitments and corrective actions are discussed in this
Inspection Report and Inspection Report 50-344/89-22.
At the Enforcement
!
Conference conducted on August 24, 1939, the licensee committed to "evise
this LER when the results of their evaluation of the effects the deNis
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found in the sump was complete.
The licensee concluded the cause of the event was inadequate procedural
compliance, inadequate management involvement in plant events, inadequate
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procedures, failure to complete all construction activities and failure
to verify the implementation of system design features.
Corrective
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actions included revision to plant procedures, improved pre-inspection
!
briefings, improved training, re-performance of system walkdowns to
verify design basis, disciplinary action for personnel who did not
perform to expectations and recognition for those who performed in excess
of expectations.
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No violations or deviations were identified.
8.
Seismic Issues
Reactor Trip Breaker Not Enoaoed
The licensee identified that both the Reactor Trip Breakers (RTBs) did
not have full engagement of the RTB positioning latchesi Particularly,
the Right Hand Side (RHS) latch was found not to be fully engaged on both
breakers.
At 2:55 p.m. on July 26, 1989, the plant was in mode 2 when a licensee
electrician initially discovered that the A RTB was not fully engaged.
The plant was in Mode 2.
An urgent MR was written to fix the problem,
and this RTB was fully latched by 4:19 p.m.
The Quality Operations
oepartment made several recommendations, which included more training for
the operators and the use of visual aids to indicate proper breaker
,
installation.
The licensee wrote Event Report (ER)89-113 on July 27,
1989 for this event.
At 12:15 am on August 1, 1939, the control room log
notes that the B RTB was also found not fully latched.
Earlier,
maintenance had found that the B RTB Right Hand Side latch was not fully -
i n.
The RTB was put into the latched position.
The operations manager
did not write a new event report; he merely added the new breaker onto ER
89-113 evaluation.
The new entry was logged in the control room log at
QA insistence. The corrective actions included that electrical
maintenance department would take over responsibility for racking in the
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breakers, and weekly visual surveillances on the breakers would be
performed to verify proper RHS latch engagement.
The inspector's had a concern about the seismic adequacy of the breakers.
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The RTB's are identified as Seismic Class I in sectien 3.2.1 of the FSAR.
>
The licensee took measurements on a spare, identical RTB in the
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warehouse, and attempted to analyze the significance of not having the
.
RHS latch fully engaged.
Their analysis had not been fully checked as of
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September 21, 1989, but the results of the analysis revealed that the RTB
'
could move 1/4" on the rail.
Since the RTBs were tested with both
'
latches engaged, the amount of movement analyzed renders the effect on
,
!
operability indeterminate.
In discussions with the licensee, the
[
licensee's civil engineers believe that the only way to determine if the
RTB would open would be to test it in the configuration with the RHS
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latch not engaged.
}
The licensee also has a letter from Westinghouse (dated 9/11/89) in which
Westinghouse states that the RTB would open during the design basis
seismic event event if the latch was not fully engaged.
Seismic Design Requirements
During the NRC inspection to determine the purpose of the Right Hand Side
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(RHS) latch of the reactor trip breaker, seismic qualification of the
breaker was discussed.
Questions raised by the inspector on seismic
analysis techniques promoted the licensee to research the facility Final
Safety Analysis Report (FSAR) for the method of seismic qualification to
which PGE committed.
Seismic Category I equipment is listed in section
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3.2.1 of the FSAR, and the method of qualifying equipment is noted in
section 3.7 of the FSAR.
The licensee determined they had committed to
seismically qualify Category I equipment by the Absolute Sum Method (FSAR
i
section 3.7).
Further, the licensee recognized that they had not always
been analyzing their seismic design in accordance with section 3.7 of the
FSAR; they were in cases using other methods as identified in Regulatory
Guide 1.92, " Combining Modal Responses and Spatial Components in Seismic
Response Analysis." The licensee had not committed to this Regulatory
)
Guide (RG).
The licensee in-house position (IHP) 1.92-1-1 to RG 1.92
,
noted that this guide is not applicable to Trojan.
As a result of these
findings, the licensee generated Non-Conforming Activity Report (NCAR)
P89-380M, documenting that IHP 1.92-1-1 states that they will use chapter
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3.7 of the FSAR for seismic design.
One of the recommended actions noted
'
on NCAR P89-380M was to determine which method to use in performing
seismic design analysis in the future (FSAR 3.7 or RG 1.92) followed by
'
making necessary revisions to the FSAR.
,
The inspector pointed out to the licensee that Trojan Technical Specification 5.7.1 states that the seismic design shall be designed and
maintained to the original provisions contained in section 3.7 of the
FSAR. The licensee revised NCAR P89-380M to recognize this problem.
Specific examples where seismic snalysis was performed using techniques
different than those required by the FSAR include the modifications to
the control room emergency ventilation system and the analysis on the
design for the new battery rack.
'
At the conclusion of the inspection, the licensee was reviewing their
!
calculations to verify that the other methods used do not give less
conservative answers than by the methods specified in the FSAR.
This use
of other design methods than specified in the FSAR will be followed as an
Unresolved Item pending full understanding of the licensee's design
analysis methods and the inpact on system design (50-344/89-20-02).
Control Room Wall Seismic Analysis
On September 7, 1989, the licensee identified that part of the control
room boundary seismic analysis that was to have been performed by Bechtel
in 1987 had not been performed. The analysis that had not been performed
concerned the wall above the entrance to the control room which is part
of the control room boundary envelope.
The control room envelope is
.
required by Technical Specification to maintain the dose limits to the
operators following an accident to low levels.
The licensee initiated
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Non-Conformance Report (NCR)89-399, to document this lack of seismic
,
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analysis.
The inspector became aware of this concern on September 12, 1989 as part
of routine inspection activities.
Per NDP 600-3, a licensee event report
was submitted within five working days.
The licensee noted that in their
judgement and Bechtel's initial judgement, it was likely that the wall
would be adequate.
The civil supervisor showed the inspector a memo to
that effect.
Because the inspector thought that the JC0 should be
processed since the analysis had not yet been performed, he reviewed the
licensee JC0 file and noted a JC0 had not been implemented.
The
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licensee's procedure, NDP 100-15, " Preparatory Review and Approval of
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Justifications for Continued Operation," establishes the requirements for
preparation, review, and approval of JCO's.
This procedure defines a JC0
as "A written evaluation used to support the conclusion that the
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operation of the Trojan Nuclear Plant may continue during the time needed
,
to correct a nonconforming or degraded condition or to resolve a
regulatory issue." The inspector discussed this with the Manager of
Technical Services and the Manager of Nuclear Plant Engineering (NPE) and
'
stated that per NDP 100-15 it appeared a JC0 was warranted.
The Manager
of NPE stated that he was not fully aware of the requirements of when to
issue a JCO. The Manager of Technical Services concurred that a JC0
warranted, and stated that a JC0 would be written.
NDP 100-15 also notes
that, "the need to prepare a JC0 muy be determined by the responsible
supervisor assigned to the corrective action evaluation of an NCR, NCAR,
or ER or the reviewing department manager during the evaluation of a
regulatory issue." The Manager of NPE was responsible for this JCO.
As
of Monday, September 18, 1989, this JC0 was in the approval process.
One violation was identified.
9.
Severity Level V Violations
As stated in Section V. A of 10 CFR Part 2, Appendix C, " General
Statement of Policy and Procedure for NRC Enforcement Actions," 53 Fed.
Reg. 40019 (October 13,1988), a Notice of Violation will not normally be
issued for isolated Severity level V violations provided that the
licensee has initiated appropriate corrective actions before the
inspection ends.
One apparent Severity Level V violation for which a
Notice of Violation was not issued is discussed in paragraph 5 of this
report.
10.
Exit Interview (30703)
The inspectors met with the licensee representatives denoted in paragraph
1 on September 18, 1989, and with licensee management throughout the
inspection period.
In these meetings the inspectors summarized the scope
!
and findings of the inspection activities.
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