ML18065B148
| ML18065B148 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 01/21/1998 |
| From: | Burgess B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML18065B146 | List: |
| References | |
| 50-255-97-13, NUDOCS 9801270083 | |
| Download: ML18065B148 (15) | |
See also: IR 05000255/1997013
Text
U.S. NUCLEAR REGULATORY COMMISSION
Docket No.
License No.
Report No.
Licensee:
Facility:
Location:
Dates:
Inspector:
~pproved by:
9801270083 980121
ADOCK 05000255
G
REGION Ill
50-255
50-255/97013(DRP)
Consumers Power Company
212 West Michigan Avenue
Jackson, Ml 49201
Palisades Nuclear Generating Plant
27780 Blue Star Memorial Highway
Covert, Ml 49043-9530
October 18 through December 5, 1997
P. Prescott, Resident Inspector
B. Fuller, Resident Inspector, D.C. Cook
E. Schweibinz, Regional Inspector
Bruce L. Burgess, Chief
Reactor Projects Branch 6
EXECUTIVE SUMMARY
Palisades Nuclear Generating Plant
NRC Inspection Report No. 50-255/97013
This inspection reviewed aspects of licensee operations, maintenance, engineering, and plant
support. The report covers a seven-week period of resident inspection.
Operations
The inspectors identified a violation in that procedure SOP-1, "Primary Coolant System,"
Revision 38, was inappropriate for the circumstances. This procedure allowed the
operators to start a primary coolant pump without verifying that the Technical
Specification requirements for starting forced circulation were met. The inspectors were
concerned about the similarity of this event to an event identified in Inspection Report
No. 50-255/97008 (Section 01.2).
The licensee was required to enter a second forced outage to repair relief valve RV-2013
bellows. An operator workaround for chemical volume and control system (CVCS)
pressure control, in conjunction with material condition problems on the turbine stop valve
bypass valves and an unusual eves system configuration, resulted in an RV-2013
bellows failure. The inspectors concluded that adequate corrective actions had been
planned or taken to prevent recurrence of this problem (Section 01.2). *
Maintenance
The inspectors noted that most maintenance was conducted in a professional and
thorough manner. All work observed was done with the work package present and in
active use. Work packages were comprehensive for the task and post maintenance
testing requirements were adequate. The inspectors frequently observed supervisors
and system engineers monitoring work. When applicable, work was done with the
appropriate radiation control measures in place (Section M1 .1 ).
The licensee's preparation for and conduct of the work for the main steam bypass valve
repair was good. However, the inspectors noted a weakness in management oversight of
the job. Once all preparatory work was done, no single individual had overall
responsibility for scheduling and completing the repair (Section M1 .2).
Engineering
The inspectors determined that the licensee's actions were adequate to address the
atmospheric dump valve hot short Appendix R scenario and rebaselining of fire dampers
and barriers. The inspectors also concluded that the Appendix R review team was
adequately staffed and supported. However, the inspectors were concerned with plans to
potentially reduce the Appendix R evaluation effort should resources be needed to
support the upcoming 1998 refueling outage. The inspectors also stressed the
importance of a timely response to the longstanding Appendix R issues (Section E1 .1).
2
The engineering department's operability evaluation and assistance for preparations for
the repairs to main steam isolation valve (MSIV) M0-051 O were thorough. The
engineering department's efforts had improved over those associated with previous
similar MSIV repairs (Section E1 .2).
Plant Support
During an emergency preparedness drill, the licensee identified a deficiency involving a
. prolonged period of time before a search and rescue team was sent to find a simulated
injured individual. The licensee stated that a review will be performed to correct the
response timeliness concerns (Section P1 .1) .
3
Report Details
Summary of Plant Status
The plant began the inspection period at 80 percent power due to a forced maintenance outage
to repack the UB" reheater drain pump. Repairs were completed and power escalation was
resumed on October 21, 1997. The unit was at full power October 22, 1997. The plant remained
at full power for the remainder of the inspection period.
I. Operations
01
Conduct of Operations
O 1. 1
General Comments (71707)
Using Inspection Procedure 71707, the inspectors conducted frequent reviews of ongoing
plant operations. Several weaknesses were noted when operations took all control rods
out of service to perform maintenance while at power. This event was detailed in special
Inspection Report No. 50-255/97014. Other specific events and noteworthy observations
are detailed below.
01.2
Starting Forced Circulation with Steam Generator Secondary Temperature Above Cold
Leg Temperature
a.
Inspection Scope (71707)
The inspectors reviewed the circumstances and events surrounding starting primary
coolant pump (PCP) P-500 while steam generator secondary temperature was above
cold leg temperature.
b.
Observations and Findings
On October 12, 1997, a plant heat up from a short maintenance outage was in progress,
shutdown cooling was in operation, and the operations shift was preparing to start
PCP P-500. Because the outage was expected to last less than 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br />, the steam
generators were not placed on recirculation nor was nitrogen bubbled* through the steam
generators. Per Procedure SOP-1, UPrimary Coolant System," Revision 38, the
parameters for starting PCP P-500 were verified, and PCP P-500 was started, causing a
brief pressure rise. Shutdown cooling return temperature was 130° F, cold leg
temperature (T coid) for PCP P-500 was 127° F, and the steam generator hand-hole
pyrometer temperatures were 125.2° F for the "A" steam generator and 129.6° F for the
"B" steam generator.
Precautionary measures were in place in the event that primary coolant system pressure
changed significantly after starting PCP P-500. Consequently, the operators limited the
pressure rise, and no low temperature overpressure protection actuation occurred. The
pressure transient was within the design capabilities of the primary coolant system (PCS)
and the shutdown cooling system; therefore, the actual safety significance of this event
was minor. The basis for Technical Specification (TS) 3.1.1 stated, in part, "The
4
requirement that the steam generator temperature be s than the PCS temperature when
forced circulation is initiated in the PCS ensures that an energy addition caused by the
heat transferred from the secondary system to the PCS will not occur." From the amount
of primary coolant system pressure rise following the start of the PCP, it was apparent
that the bulk steam generator secondary temperature could not have been less than T cold;
therefore, when the operators started PCP P-500, a violation of TS 3.1.1.h occurred.
Procedure SOP-1, Revision 38, required, in part, that the operators, "Compare
temperature readings obtained in Step 4.3.1.b.1 [steam generator hand-hole pyrometer
temperatures] to Shutdown Cooling return temperatures (when Shutdown Cooling is
operating) or loop T cold instruments (when Shutdown Cooling is secured) and refer to
TS 3.1.1.h." This step contradicted TS 3.1.1.h.(2) which required comparing steam
generator secondary temperature to T co1d when staring the first PCP. Also, procedure
SOP-1 did nottake into consideration that the steam generator inventory may not be
mixed if the steam generators were not placed on recirculation or nitrogen bubbling. The
steam generators were stratified with the colder water in the lower part of the steam
generators, where the hand-hole is located.
The inspectors concluded that one root cause of the TS violation was that procedure
SOP-1 was inadequate for the circumstances in that it failed to ensure that TS 3.1.1.h
requirements were met. This procedure also failed to ensure that a representative steam
generator secondary temperature was obtained for comparison to T cold* This was a
violation of 10 CFR Part 50, Appendix B, Criterion V, "Instruction, Procedures, and
Drawings," (50-25/97013-01 (DRP)).
The inspectors were also concerned about the TS aspects of this event and the lack of a
questioning attitude by the operators involved. Recently, a similar violation
(50-255/97008-01 (DRP)) was issued for a procedure which did not adequately prevent
operation of the reactor above the licensed thermal power limits. In the earlier case, the
TSs were not violated; however, in this event, the operators started PCP P-500 and
violated the TS even though procedure SOP-1 required the operators to refer to the
appropriate TS.
Operations management participated in a critique of this event with the licensed
operators involved. The emphasis was on compliance with TSs and making conservative
decisions with respect to TS limits. Other corrective actions have been proposed to
improve procedural adherence and training aspects related to this event.
c.
Conclusions
The inspectors identified that procedure SOP-1, "Primary Coolant System," Revision 38,
was inappropriate for the circumstances. This procedure allowed the operators to start a
primary coolant pump without verifying that the TS requirements for starting forced
circulation were met. The inspectors were concerned about the similarity of this event to
an event identified in Inspection Report No. 50-255/97008.
5
01.3
Chemical Volume and Control System (CVCS) Relief Valve Operation
a.
Inspection Scope (71707)
The inspectors reviewed the circumstances that led to the operation of the CVCS relief
valve (RV)-2013 and discussed this event with operations personnel. The subsequent
licensee actiors to repair the relief valve and continue the ongoing plant startup were also
observed.
b.
Observations and Findings
The operators were in the process of a plant heatup on October 9, 1997. The main
steam isolation valves (MSIV's) were open to supply steam to the air ejectors and turbine
gland sealing system. The turbine electro-hydraulic system was placed in operation and
then the turbine was tripped. Following the turbine trip, the operators noticed that the
primary coolant system (PCS) was cooling down. The operators called the turbine
system engineer to assist in troubleshooting. The system engineer determined that the
No. 1 turbine stop valve bypass valve and the associated governor valve had stuck
partially open, allowing a steam flow path to the condenser, causing the PCS cooldown.
The No.1 turbine stop valve bypass valve was closed by manual operation to stop the
cooldown.
The next operating shift started a second charging pump and increased letdown for
chemistry control, causing the differential pressure across the in service eves
demineralizer to increase; however, no attempt was made to reduce the higher than
normal differential pressure across the demineralizer. The operations shift expected that
the eves would be in that condition for only a short time and did not want to pick up
radiation dose adjusting the downstream demineralizer flow control valve (CV)-2033.
The oncoming operations shift was not made aware during shift turnover that the
demineralizer differential pressure was high. This shift found the No. 1 turbine stop valve
bypass valve sticking open again. The valve was stroked twice to try and reseat it,. but it
stuck further open, and the PCS began to cool down again. Operators closed the MSIVs *
and throttled the MSIV bypasses which increased PCS temperature, causing pressurizer
level to increase and the third letdown orifice stop valve to open. This caused RV-2013
to open because the demineralizer differential pressure was already high. The relief
valve bellows subsequently failed, resulting in a primary coolant leak. The licensee had
to enter a second forced outage in order to repair the relief valve bellows.
The inspectors noted several causal factors for this event:
A modification to the eves to remove the boron meter did not address known
system pressure control problems. This had resulted in operators having to
manually control CV-2033 when charging and letdown conditions changed.
The leaking turbine valves resulted in an unexpected PCS cooldown.
The off-going operations shift failed to discuss the current status of the eves with
the oncoming shift.
6
The licensee's review of this event was made part of a level two condition report initiated
to address other recent operations problems. Specifically, the following corrective actions
were planned or taken :
The CVCS system would be tested to determine the best method for controlling
eves demineralizer differential pressure.
The turbine stop valve bypass valves would be repaired during the next scheduled
outage.
The sequence of pre-startup testing would be changed to move the turbine
electro-hydraulic system test to a period when PCS cooldown would not be a
problem.
This event would be discussed with all operating shifts, emphasizing the need to
be aware of plant and system status.
This event appeared to be an isolated occurrence, and the planned corrective actions
appeared to be adequate to prevent recurrence.
c.
Conclusions
The licensee was required to enter a second forced outage to repair relief valve RV-2013
bellows. An operator workaround for CVCS pressure control, in conjunction with material
condition problems on the turbine stop valve bypass valves and an unusual eves system
configuration resulted in an RV-2013 bellows failure. The inspectors concluded that
adequate corrective actions had been planned or taken to prevent recurrence of this
problem.
II. Maintenance
M1
Conduct of Maintenance
M1 .1
General Comments
a.
Inspection Scope (62707 and 61726)
The inspectors observed all or portions of the following work and surveillance activities:
Work Order No:
24712528
24712459
24612117
Diagnostic testing for control Valve (CV)-0733 hotwell
makeup valve
Emergency diesel generator (EOG) 1-2: calibrate jacket
water, lube oil and fuel oil temperature switches, indicators
and controls
EOG 1-2: install room cooling fan V-24C controls
7
24714364
24714556
Surveillance Activities
SOP-3
Q0-1
b.
Observations and Findings
M0-0510 main steam isolation valve bypass valve: replace
leaking stuffing box plug
Safety injection tank T-82C: troubleshoot fuse S46-1
circuitry. Fuse blew during safety injection system
actuation logic testing
Safety Injection and Shutdown Cooling System (special test
for high pressure safety injection min-flow check valves)
Safety Injection System
The inspectors noted that the work was conducted in a professional and thorough
manner. All work observed was done with the work package present and in active use.
Work packages were comprehensive for the task and post maintenance testing
requirements were adequate. The inspectors frequently observed supervisors and
system engineers monitoring work. When applicable, work was done with the appropriate
radiation control measures in place. Overall, the inspectors observed good procedure
adherence with good maintenance and radiation work practices. However, the
inspectors noted a weakness in the repairs to the main steam bypass valve in that once
all preparatory work was done, no single individual had overall responsibility for
scheduling and completing the repair. Specific observations are detailed below.
M1 .2
Repairs to Leak on Main Steam Bypass Valve
a.
Inspection Scope (62707)
On November 4, 1997, a small steam leak was identified on the bonnet of M0-0510, the
steam generator "A" main steam isolation valve (MSIV) bypass valve. The leak was
coming from a set screw improperly used as a plug. On November 22, the inspectors
attended the pre-job brief and observed the work in progress. The work order package
and post maintenance test were also reviewed.
b.
Observations and Findings
The valve repair work was done by the licensee's temporary leak repair contractor. The
inspectors noted that the pre-job brief was detailed and that there was extensive licensee
oversight during pre-job planning. However, the inspectors did identify a weakness in
supervisory oversight of the work in progress. Once all preparatory work was done by the
departments involved, no single individual had overall responsibility for scheduling and
completing the repair. The inspectors did not note any deficiencies in the manner in
which the work was performed. No more leakage had been observed by the end of the
inspection period.
8
, ..
'
This repair was of particular concern due to contractor and job control issues identified in
connection with repairs to the main steam isolation valves (detailed in Inspection Report
Nos. 50-255/96017 and 50-255/97005). The inspectors followed up on the licensee's
review of the original non-code repair done on M0-0510. A contractor perfonned a
temporary leak repair to M0-0510 offsite under specification change (SC)-92-109 which
also specified the pennanent repair method. However, the pennanent repair was made
under a different work order than the SC, and the second work order did not reference the
original SC. Therefore, with no directions to follow, the repair was made using an
incorrect part (set screw, vice a high pressure pipe plug), with a resultant leak. The
apparent cause of this condition was a failure of the work order process. Additional
details concerning the temporary repair are discussed below in Section E1 .2.
The licensee reviewed a list of all temporary leak repairs done at Palisades over
approximately a ten year period. If the repair documentation was questionable, the
pennanent repairs were checked visually in the field. No other questionable repairs were
found. The licensee's investigation into the 1996 valve refurbishment was still ongoing.
c.
Conclusions
The licensee's preparation for and conduct of the work for the main steam bypass valve
repair was good. However, the inspectors noted a weakness in management oversight of
the job. Once all preparatory work was done, no single individual had overall
responsibility for scheduling and completing the repair.
Ill. Engineering
E1 Conduct of Engineering
E1 .1
Atmospheric Steam Dump Valve Appendix R Issue
a.
Inspection Scope (37551)
The inspectors reviewed the licensee's recent findings, applicable documentation, and
compensatory measures related to the Appendix R enhancement effort. Discussions
were held with the system engineering supervisor and personnel supporting the effort.
Future efforts to bring the Appendix R review to a close were discussed with licensee
management.
b.
Observations and Findings
On October 4, the licensee concluded that an unanalyzed condition existed involving a
cable which runs between two control room cabinets. A single hot short in the control
room cabinets or a single hot short in the cable spreading room could potentially result in
all four atmospheric dump valves (ADVs) and turbine bypass valves spuriously opening
due to the effects of a fire in either of the areas. The licensee also identified potential
inadequacies with the engineering evaluations of some fire dampers and barriers. The
licensee detennined that both conditions were reportable and submitted licensee event
reports.
9
Previous Appendix R analyses assumed that only two ADVs would spuriously open as a
result of a fire. Off normal Procedure (ONP)-25.2, "Alternate Safe Shutdown Procedure,"
stated that with two ADVs open, control must be established within ten minutes. The
new evaluation established a six minute response time to take manual action to close all
four ADVs. The response time was validated on the simulator and in the plant.
Procedure ONP 25.2 was revised to ensure timely completion of manual actions to close
the ADVs and subsequently initiate auxiliary feedwater in the case of fire with opening of
the ADVs. Operators were trained on the procedure revision.
The licensee's efforts on rebaselining fire dampers and barriers were also reviewed. The
licensee intends to create design basis documents and acceptance criteria for fire
dampers and barriers. Fire tours have been instituted as a compensatory measure until
the analysis on the fire dampers and barriers is completed.
As follow up to earlier enforcement action for Appendix R issues that involved inadequate
corrective actions, detailed in Inspection Report No. 50-255/96004, discussions were h~ld
on the present resources being applied to complete the Appendix R review. The
inspectors concluded that the Appendix R review team was adequately staffed and
supported. As previously discussed in Inspection Report No. 50-255/97011, the
licensee's efforts were progressing slowly, but the review seemed thorough. However, in
recent discussions, the engineering supervisor said that with the upcoming refueling
outage, planned to commence in April 1998, the Appendix R resources may be reduced
to support the outage. This concern was discussed at the exit interview. At this time, no
long term reduction in the Appendix R resources are planned.
c.
Conclusions
The inspectors determined that the licensee's actions were adequate to address the
atmospheric dump valve hot short Appendix R scenario and rebaselining of fire dampers
and barriers. The inspectors also concluded that the Appendix R review team was
adequately staffed and supported. However, the inspectors were concerned with plans to
potentially reduce the Appendix R evaluation effort should resources be needed to
support the upcoming 1998 refueling outage. The inspectors also stressed the
- importance of a timely response to the longstanding Appendix R issues.
E1 .2
Steam Leak on Main Steam Bypass Valve
a.
Inspection Scope (37551)
The inspectors reviewed the engineering department's actions to evaluate the steam leak
on main steam stop bypass valve M0-0510.
b.
Observations and Findings
The leak was coming from a set screw improperly used as a plug (discu~sed in
Section M1 .2). Steam leakage from the bypass valve to the atmosphere could result in
the release of radioactivity outside containment if steam generator tube leakage existed;
however, none of the steam generators currently exhibit tube leakage.
10
The set screw had been installed in the bonnet of M0-0510 during valve refurbishment
done in the 1996 refueling outage. The set screw was used to plug a leak sealing
injection port as part of a 1993 packing leakage repair. The steam was leaking around
the circumference of the set screw. The valves are designated as Class II pressure
boundaries per Section XI of the American Society of Mechanical Engineers Code.
On November 4, 1997, a meeting was held to determine the operability of the MSIV
bypass with bonnet leakage. The leakage was determined to be from a mechanical joint
in the valve and did not affect operability of the valve; however, the licensee began
planning repairs to stop the leakage. Additionally, engineering personnel did a stress
analysis for the existing configuration, using worst case plug material and the measured
thread engagement. The existing plug thread engagement was determined to be
adequate.
On November 6, 1997, additional meetings were held to discuss the time line for repairing
M0-0510. Analyses were done to document the continued operability of the valve with
the existing amount of leakage and with increased leakage. A course of action was
implemented for the operators to follow until the formal work process was developed for
the repairs. The plan required the operators to monitor valve leakage and shut down the
unit if steam leakage increased to that equivalent from an unplugged hole of the same
diameter (3/8-inch).
As part of the repair planning effort, the licensee's engineering staff requested a
radiography of the valve bonnet to determine the exact nature of the required repairs.
Review of the radiographs revealed that the initial repair was not in accordance with the
specifications provided to the repair contractor. Specifically, the set screw thread
engagement and use of a set screw for this purpose was suspect. A pipe plug should
have been installed. A non-code repair on the main steam isolation valves was the
subject of an earlier Violation (50-255/97008-01 ). As discussed above in Section M1 .2,
the licensee conducted a review of all temporary valve repairs completed during the last
ten years and found no additional examples of a non-code repair; therefore, the
inspectors considered the non-code temporary repair to M0-0510 as an additional,
example of Violation 50-25S/97008-01.
c.
Conclusions
The engineering department's operability evaluation and assistance for preparations for
the repairs to main steam isolation valve (MSIV) M0-0510 were thorough. The
engineering department's efforts had improved over those associated with previous
similar MSIV repairs.
11
IV. Plant Support
P1
Conduct of Emergency Preparedness (EP) Activities
P1 .1
EP Drill Observations
a.
Inspection Scope (71750)
The inspectors observed activities in the operational support center (OSC) and in the
plant for an EP Drill. The subsequent OSC drill critique was also observed.
b.
Observations and Findings
The drill scenario had an explosion occur in track alley with no radioactive release. There
was an individual simulated injured in the explosion. The inspectors noted that the
licensee waited until the conclusion of the personnel accountability phase, which
identified that an individual was unaccounted for, before sending a search and rescue
team to look for the missing individual. Further time was then spent getting the team
ready to go into the plant to search for the individual. No emphasis was placed on
locating the missing individual given that a serious event had occurred in which personnel
could have been injured.
The licensee's post-drill critique was observed. The inspectors noted good participation
in the critique by licensee personnel. Licensee personnel expressed frustration with their
inability to make a timely response to the "injured" individual. The drill coordinators noted
the weaknesses and stated efforts would be made to look at improving response times.
c.
Conclusions
During an emergency preparedness drill, the licensee identified a deficiency involving a
prolonged period of time before a search and rescue team was sent to find a simulated
injured individual. The licensee stated that a review will be performed to correct the
response timeliness concerns.
V. Management Meetings
X1
Exit Meeting Summary
The inspectors presented the inspection results to members of licensee management at
the conclusion of the inspection on December 5, 1997. No proprietary information was
identified.
12
PARTIAL LIST OF PERSONS CONTACTED
Licensee
R. A. Fenech, Senior Vice President, Nuclear, Fossil, and Hydro Operations
T. J. Palmisano, Site Vice President - Palisades
G. B. Szczotka, Manager, Nuclear Performance Assessment Department
D. W. Rogers, General Manager, Plant Operations
K. M. Haas, Acting Director of Engineering
S. Y. Wawro, Director, Maintenance and Planning
J. L. Hanson, Director, Strategic Business Issues
R. J. Gerling, Design Engineering Manager
A. L. Williams, Acting Manager, System Engineering
T. C. Berdine, Manager, Licensing
J. P. Pomeranski, Manager, Maintenance
D. G. Malone, Shift Operations Supervisor
M. P. Banks, Manager, Chemical & Radiation Services
IP 37551:
IP 61726:
IP 62707:
IP 71707:
IP 71750:
INSPECTION PROCEDURES USED
Onsite Engineering
Surveillance Observations
Maintenance Observation
Plant Operations
Plant Support Activities
ITEMS OPENED
50-255/97013-01
Operators failed to meet TS requirements for starting of a primary
coolant pump
50-255/97013-02
None
Inadequate procedure allowed operators to determine primary
coolant pump start criteria not in accordance with TSs
ITEMS CLOSED
. .,;
- .....
.,,
ADV
CFR
CROM
CV
eves
EOG
IP
MO
NCO
NRC
ONP
osc
.Qo
RV
SC
soc
TS
LIST OF ACRONYMS USED
Atmospheric Dump Valve
Code of Federal Regulations
Control Rod Drive Mechanism
Control Valve
Chemical Volume & Control System
Division of Reactor Projects
Inspection Procedure
Low Temperature Overpressure
Motor Operated (valve)
Nuclear Control Operator
Nuclear Regulatory Commission
Off Normal Procedure
Operational Support Center
Primary Coolant Pump
Primary Coolant System
Pressure Control Valve
Public Document Room
Quarterly Operating (procedure)
Relief Valve
Specification Change
Safety Injection System
System Operating Procedure
Technical Specification
Violation*