ML17158A023
| ML17158A023 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 11/16/1993 |
| From: | Drysdale P, Eapen P, Kenny T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML17158A022 | List: |
| References | |
| 50-387-93-08, 50-387-93-8, 50-388-93-08, 50-388-93-8, NUDOCS 9312070091 | |
| Download: ML17158A023 (19) | |
See also: IR 05000387/1993008
Text
U. S. NUCLEAR REGULATORY COMMISSION
REGION I
REPORT/DOCKET NOS.
50-387/93-08
50-388/93-08
LICENSE NOS.
NPF-22
LICENSEE:
FACILITYNAME:
INSPECTION AT:
Pennsylvania Power and Light Company
2 North Ninth Street
Allentown, Pennsylvania
18101
Susquehanna
Steam Electric Station
Allentown,, Pennsylvania
Salem Township, Pennsylvania
King of Prussia,
INSPECTION DATES:
August 16 - 20, 1993
INSPECTORS'ichard
S. Paroby, Reactor Engineer Co-op
=~
P.
Peter D. Dry
e, Sr. Reactor
ngineer
Systems Section, EB, DRS
ll(I( (93
Date
Thomas J. Kenny, Sr. Reactor
ngineer
Systems Section, EB, DRS
I< Jtgi$ 3
Date
APPROVED BY:
Dr. Plackeel K. Eapen, Ch ef
Systems Section, EB, DRS
i( /Q
Date
931207009'i
931126
ADOCK 05000387
8
2
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and activities, site technical support, installation and testing of plant modifications, and the
motor-operated valve program for both units.
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Department.
This has improved the department's efficiency and reduced its overall
workload.
Also, some reduction in personnel was involved.
Engineering programs and
issues are well integrated with the PP&L Nuclear Department strategic goals and business
plans.
A revised Engineering Deficiency Report system has shown improvements in areas
related to operability and reportability determinations.
The licensee's GL 89-10 program was
put on hold in early 1993, in order to revise the engineering methodology used to perform
thrust calculations and to determine correct switch settings.
DETAILS
1.0
ENGINEERING AND TECHNICALSUPPORT PROGRAM ACTIVITY
(37700)
1.1
Engineering Organization
A two year planned transition was being implemented in accordance with the Organizational
Effectiveness Review (OER) to restructure the engineering organizations into functional
category groups and eliminate the alignment along basic engineering disciplines.
The
realigned engineering organization consists of the System Engineering, Nuclear Technology,
Modifications, and Nuclear Fuels groups.
This realignment is designed to improve utilization of engineering resources,
reduce the
overall engineering workload, increase work efficiency, and increase individual ownership
and technical responsibility of engineering tasks.
Before the reorganization,
the system
engineers were working approximately 25-30% overtime.
After the reorganization was
substantially completed, system engineers
averaged
about 5-8% overtime.
The
reorganization also increased interactions between the engineering organizations and the site
and improved the level and effectiveness of communications between those groups.
There is
improved engineering support of site activities and an increased
safety perspective on the part
of both engineering and site groups.
The engineering programs and issues within the
reorganized department are well integrated with the PP&L Nuclear Department strategic
goals and business plans.
As of August 1993, the reorganization was physically in place.
The OER implementation
plan projected two years to complete the reorganization and to make final adjustments
as
necessary.
On November 9, 1993, the licensee indicated that the reorganization was
structurally in place.
However, minor organizational enhancements
willbe ongoing as
necessary
to adjust to changing work loads and functional requirements.
Ongoing procedure
revisions and upgrades willrequire organizational effectiveness reviews that may result in
additional refinements in the engineering organization.
1.2
Self Assessment
Processes
The licensee conducted a Self-SALP in May 1993, and made a formal presentation of the
results to Region I management.
This self-assessment:
~
reviewed the licensee's own assessments,
audits, significant events, third party
reviews, and past NRC inspections to determine strength and weaknesses;
~
focused on management;
0
4
~
acknowledged the need to manage employee concerns,
and;
~
acknowledged
need to pursue better engineering training, improvements in system
performance,
and in management of deficiency resolutions.
1.3
Control of Design Changes and ModiTications
1W
r Level In trumen
i n M ifi ti n In
la i n
PP&L recently developed a plant modification to install new reactor vessel level
instrumentation designed. to overcome potential water level indication inaccuracies
caused by
the evolution of non-condensible
gases from the level instrument reference legs.
The inspectors reviewed the modification package and observed the progress of equipment
installation.
System engineers were knowledgeable on details of the modification and closely
monitored its installation.
An appropriate level of QA/QC inspections were designated
to
observe the installation and to verify that the specified levels of work quality were present.
The work practices observed by the inspectors were well controlled and the installed
equipment met the specifications and requirements contained in the modification work
packages.
Post installation tests were included with the modification package and they
specified the appropriate functional and preoperational
tests for the new instrumentation.
1.4
Engineering Deficiency Reports (EDRs)
As detailed in NRC inspection reports 50-287;288/92-14, 50-287;288/92-28 and
50-287;288/93-04,
the licensee's EDRs lacked detailed information related to plant events,
did not identify potential generic implications of events, and did not directly address
the
potential impact of EDRs on technical specifications operability criteria.
Also, the
reportability evaluation process for nonconforming conditions was not adequately defined.
In recognition of these concerns, PP&L formed an Engineering Discrepancy Management
Task Group to examine the EDR process in depth and to make recommendations
for
improvement.
This task group identified improvements in the processes of reporting,
resolving, tracking, and closing EDRs.
A new Nuclear Department Administrative
Procedure, NDAP-QA-0740, was issued to document the improved Engineering Deficiency
Report process.
Since many EDRs are resolved through the installation of a plant modification, the licensee
allows one refueling cycle to close an EDR after it is issued.
The goal was not to extend
more than 5% of the EDRs beyond one refueling outage.
A small number of EDRs were
extended beyond this goal.
The licensee documented justifications for extending these EDRs.
In all cases,
these justifications were reasonable for extending the due date.
The inspectors
verified that the modifications associated
with the extended EDRs were being prepared and
were scheduled for installation the following refueling outage,
In most cases,
these
extensions involved minor modifications; however, some major modifications were also
extended.
For example, modifications associated with EDR ¹610091, "Single Failures that
Affect Operability of Equipment Required for Accident Mitigation and Cause Degraded Bus
Voltages," were extended twice; once to November 19, 1993, and then again to the end of
the sixth refueling outage in Unit 2 to allow for installation.
Although delayed,
modifications associated
with EDR ¹G00088, "Recirculation Pipe Jet Impingement on MSIV
Operator and Other Targets," were still within the deadline for a commitment made to the
NRC, and modifications associated with EDR ¹G10112, "Maximum Allowable Torque
Switch Settings," still met the licensee's
schedule for implementing their Generic Letter 89-10 program.
The licensee also has a goal to have less than.20% of all EDRs open for more than 180 days.
The inspectors noted that approximately 60% of all open EDRs were more than 180 days
old.
The inspectors also noted that 80% of the EDRs opened in the past 12 months and 43%
of those opened in the previous 12 months were open primarily due to the unavailability of a
refueling outage to facilitate installation.
However, this situation is not consistent with the
goal to expect only 20% of the EDRs to be open for more than 180 days.
Overall, the
licensee is making an effort to close EDRs as soon as possible and the process for processing
and resolving engineering deficiencies appears
adequate
and timely.
The inspectors interviewed SSES control room personnel to obtain an onsite perspective of
the new EDR process.
One Shift Supervisor noted that improvements have been noticed
under the revised system, especially with the way EDRs are now communicated to the
control room supervisors.
Operability concerns are communicated more quickly to the
control room from PP&L headquarters
and Shift Supervisors are brought into EDR problems
at a much earlier point in order to get SRO insights.
2.0
NRC BULLETIN93-02, "DEBRIS PLUGGING OF EMERGENCY CORE
COOLING SUCTION STRAINERS"
NRC Bulletin 93-02 required licensees
to examine their practice of using fibrous materials in
temporary filters within the containment during refueling, and the storage of temporary filters
during operation when the containment is closed.
Immediately following a LOCA, fibrous
materials could become dislodged and be transported to the suppression pool where a
sufficient accumulation of fibre could contribute to a partial loss of net positive suction head
(NPSH) in emergency core cooling system (ECCS) pumps during the post-LOCA
recirculation phase of containment cooling. PP&L responded to the Bulletin stating that they
did not use temporary filters and, therefore, would not have this problem.
However, they
reported their ongoing assessment
of the impact on ECCS suction strainers of debris and
corrosion products adhering to permanently installed fibrous material (e.g., insulation) that
could become dislodged as a result of a pipe break.
PP&L issued a voluntary licensee event report (LER) 93-007-00, regarding the potential
blocking of ECCS suction strainers from containment debris.
Within the LER, PP&L
explained the methodology and assumptions
used to analyze "jet impingement" conditions
inside containment after a pipe break.
The analysis concluded that some amount of fibrous
insulation could find its way to the suppression pool and cause partial plugging of the ECCS
suction strainers.
The inspectors discussed
the scenario outlined in the LER and the licensee
demonstrated
how the event described was plausible.
The licensee subsequently
issued a modification to replace fibrous insulation considered
susceptible to shredding during a steam line break in the most vulnerable areas of the
containment.
The modification would replace. the old material with a mirror-type canned
metal insulation.
The inspector observed several areas where the insulation had been
replaced inside the containment and noted that the new insulation contained no fibrous
material.
Discussions with PP&L engineers
and a review of modification package 93-3058E
indicated that all the fibrous insulation would be replaced in the containments buildings at
both Units
1 & 2.
This work is expected to be completed over the next several outages.
The licensee is also in the process of issuing a procedure to backflush potentially blocked
ECCS strainers with nitrogen from a 2400 psig source during an accident.
The procedure is
to be issued when the fittings needed to connect the nitrogen bottles are received on site.
3.0
NRC Gk<2%FMC LETI'ER (GL) 89-10, SAFETY-RELATED
MOTOR-OPERATED VALVETESTING AND SURVEILLANCEPROGRAM
UPDATE
During September 23-27, 1991, the NRC conducted a team inspection (report 50-287/91-80;
50-288/91-80) to assess
the GL 89-10 program at the Susquehanna
Steam Electric Station
(SSES).
In general, the team found the existing MOV program to be acceptable.
However,
there were unresolved and open items related to specific aspects of the program.
PP&L has assessed
their program in light of some of the questions raised during the team
inspection and several
10 CFR Part 21 issues that were identified after the team inspection.
This inspection identified that PP&L has completely changed the MOV program to address
the NRC questions and to address
issues such as the Part 21 identified by Liberty
Technologies that affected MOV test results and VOTES equipment inaccuracies.
In February 1993, PP&L recognized that their MOV program would not meet the entire
intent of GL 89-10, and began to revise the program.
In March 1993, a new program was
started to address
the following significant issues:
1.
2.
3.
4.
VOTES 10 CFR 21 Notification on test equipment inaccuracies
SSES Power Update
Degraded Voltage Calculations
,
6.
7.
8.
9.
10.
11.
12.
New Allowable Thrust Methodology
Spring Pack Deficiencies
Torque Measurements
Trending by VOTES
Limitorque 10 CFR 21 Notification on High Temperature Effects on AC Motors
Valve Design Factors
Rising Rotating Stem Torque
Detailed Valve-By-Valve Schedule
PP&L deferred all GL 89-10 testing during the period from about November 1992, through
April 1993, for the following reasons:
There were a significant number of design and implementation-related
issues.
These
issues affected both the allowable thrust range and the determination of the actual
thrust developed.
Therefore, the program
as it existed did not provide a conclusive
measure of valve performance.
2.
There was minimal testing during this time period (6 VOTES &4 dynamic tests).
During this period of time, the program was in transition.
The design methodology,
VOTES software, method of applying VOTES tolerances,
and method of assessing
VOTES test results was changed.
Not testing during this transition period eliminated
the possibility of using wrong criteria for testing and analyzing the results.
3.
Allavailable manpower was spent revising the Program (rather than performing
testing and analyzing tests results).
4
The new program now in place at Susquehanna
provides answers to the aforementioned
open
items.
The following delineates
problems identified by the team inspection and the
licensee's current method for resolving each item, in accordance with PP&L's new GL 89-10
program.
Section numbers in parenthesis
below refer to the sections in NRC inspection
report 50-387/91-80; 50-388/91-80 where each item appears.
I
BA I
REVIEW
E TI N22
om I
etailed eval
i n of minim m volta eav ila le
M V
u
1
2
The degraded grid voltage analysis that was in place at the time of the team inspection has
been replaced by a newer version (as a result of the EDSFI).
The degraded voltage
calculated had concluded that the voltage at the motor terminals were very low. The
degraded voltage calculations were revised using the new degraded grid analysis that
removed excess conservatism.
IZ
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WIT H
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2
This has not yet been completed by PP&L; however, it is addressed
within engineering
deficiency report (EDR) ¹630034, which consolidated all known EDR's pertaining to
GL 89-10 in April 1993, due to the revision of the GL 89-10 program.
EDR ¹630034 was
written to address
and resolve all of the significant program issues delineated above.
Evaluat
the
v lv f ct r
urin
d
i n
asi
t
and m
e chan
a r
ir
This item is not yet completed; however, PP&L has evaluated the 0.3 valve factor and has
concluded that industry and SSES data suggests
that the use of a valve factor of 0.3 may not
be conservative in all cases.
Their study recommended
that a valve factor of 0.5 should be
used for all flex wedge gate valves.
mn
'fi infr
in
1
mfri in
ffiiin
This item is not yet completed; however, after PP&L reviewed three test programs, "EPRI
MOV Flow Test Project RP-3433-15," "EPRI Rate of Loading Effects Testing Program
RP-3433-12," and "EPRI Stem to Stem Nut Lubrication Test Report RP-3433-10," they
concluded that programs identified a coefficient of friction for their lubricant (Moly 101) was
in the range of 0.10 to 0.13, and, therefore, the use of 0.15 friction factor was conservative
for sizing motor operators.
vel
ificati n
r
r
tructural limit an I
is f r
L
-1
v lv
Specification M-1509, "Specification for MOV Weak Link Analysis," has been issued to
address
the procurement of the analysis on aU valves installed at SSES.
Also, a Design
Standard, MDS-05, "MOVWeak LinkEvaluation Criteria," has been issued to specify the
requirements when determining MOV maximum allowable thrust/torque and accelerations
that includes the valve, actuator, and motor.
Ad'u t tor ue switch se tin s t
account for rate of loadin
oad sensitive behavior
as
gg)~r~ri ~
After reviewing SSES and industry testing, PP&L has concluded that an allowance of 5%
should be included in the MOV sizing calculation to compensate for rate of loading.
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ad
men
if
~ruired
This is part of EDR 630034, and willbe incorporated when the EDR is complete.
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-
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-
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Licensing Document Change 1879, revised Section 8.3.1.9 of the UFSAR to allow the use of
voltages greater than 80% in mechanical sizing evaluation of MOVs. This now conforms
with the guidance of GL 89-10, and this item is considered
closed.
Revi w the Limit r
e
tud
n am ien
em
ture effects
n
c m
rs an
inco
in
wi h
'n
lc lation
ifa
li
le
The inspector reviewed PP&L study, VE-010, "Assessment of Elevated Temperature Effects
on AC MOVs," which concluded that all MOV motors at SSES have an inherent torque
reduction, based on the 10 CFR 21 condition identified by the Limitorque Corporation.
The
results of this study, along with other emerging issues,
have been incorporated into MDS-01
actuator sizing calculations.
To date, Unit 1 has been completed and Unit 2 is being
addressed.
Approximately twenty modifications have been identified for MOVs at Unit 1.
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16 are equipped with Reliance motors and the remaining 8
are equipped with Peerless
motors.
PP&L plans to replace 4 of the Reliance motors with
Peerless.
The inspector reviewed Service Order ¹S-16098-5 that was issued to Limitorque
Corporation on April 15, 1992, to supply information to PP&L, regarding dc motor speed at
reduced voltages.
The current status is that Limitorque has provided the results of the
completed motor tests conducted by Peerless;
however, Reliance has not yet completed
testing.
This item remains open pending incorporation of the motor speed data into the
stroke time calculation.
M V TESTIN
E TION 2
In inspection reports 50-387/91-80 and 50-388/91-80 the NRC requested
the licensee to
provide a justification for the use of the parent/candidate
approach to testing for valves that
are not practicable to test prior to using this approach.
PP&L has developed VE-009, "MOV Dynamic Test Scope," that delineates the definition of
a testable or non-testable valve and explains the criteria for how a prototype test may be used
to demonstrate
the operability of an identical valve.
The procedure is comprehensive
and
discusses
the rationale for the parent/candidate
approach to testing of valves that are not
practicable to test.
10
M V MAINTENAN E AND PO T-MAINTENAN E
TING
E TI N 2
Review fr
uenc f r
rea e sam lin
and MOV Overhaul
The inspector reviewed SSES's program for maintenance
and overhaul of MOVs. The
inspector concluded the following:
Stem and stem nut lubrication is routinely done during 18-month grease sampling.
The inspector examined several valves inside of containment and confirmed the stems
had been cleaned and relubricated.
PP&L conducted an 18-month interval lubrication program to identify trends and to
assess
the adequacy of the interval using new and better grades of grease.
The
licensee analyzed the grease
samples and also sent them to a contractor for
independent analysis.
The inspector reviewed the analyses of several grease
samples
and observed good agreement between the consultants'nalysis
and PP&L's analysis.
The inspector concluded that there is now a schedule in place for overhaul of
actuators based on the results of the grease analysis.
R vi
the maintenan
r
re t r
uir theuse
f
rin
ck e t r t
h
k f r
rin
ack r lax
'
durin
verhaul
PP&L is not using a spring pack tester; however, the procedure has been changed to make
more careful measurements
during overhaul periods.
These measurements
are recorded and
compared to an as-left condition of the spring pack.
u tif an
vi ti n
from ven
r-r
mmen
ed m intenance
ch
le
The inspector verified this has been done in draft procedure,
"Preventive Maintenance
Improvement Project," package number 130, "Limitorque Valve Motor Operators NRC GL 89-10 VOTES Tested."
PP&L stated this package would be issued within the next six
months.
FAIL
RRE TIVE A TI N
A
TRE
IN
E TI N 2.8
ml
h rviw fh Prevniv Min
n ceImrvmn
Pr
m
h
n
f
1991
The inspector reviewed package number 131, "Limitorque Valve Motor Operators Butterfly
Valve Type," and package number 132, "Limitorque Valve Motor Operators Incompatible
for VOTES Testing."
PP&L is making progress in issuing the Preventive Maintenance
Improvement Program, which was put on hold during the period while PP&L was rethinking
GL 89-10 requirements.
11
Q~nl i~in
The inspector concluded that PP&L recognized that the program that existed in
February 1992, did not meet the intent of GL 89-10 and halted the entire program and
revised it. However, they did not inform the NRC of their actions.
PP&L and NRC have
had discussions
on the extension of the GL 89-10 program at SSES.
It appears
that PP&L
willbe asking for an extension of their schedule in accordance with Supplement 6 of
The extension willbe to the end of 1995.
During this inspection the NRC was
informed of the changes.
Notwithstanding, PP&L used the correct approach to enhancing
their testing program for testing MOV's. The management involvement and an aggressive
approach toward completing the program by the end of 1995, ifthe extension is granted,
were evident.
4.0
EXITMEETING
An exit meeting was conducted August 20, 1993, at the Susquehanna
Steam Electric Station
to summarize the purpose,
scope, and findings of the inspection.
The inspector's findings
and conclusions were discussed
at this meeting.
Those in attendance
are listed in
Attachment 1. At that meeting, the NRC staff focused on its concern that the licensee did
not inform the NRC that significant changes were made in the implementation of the Generic Letter 89-10 MOV program, and some minor inconsistencies
in the implementation of EDRs
were noted.
The licensee acknowledged the inspection findings at the exit meeting.
0
ATTACHMENT1
Persons
Contacted
Pnn
lv
i Pwr
n Lih
m
H. Clarke, Design Basis Document Project Manager
- T. Clymer, Nuclear Quality Assurance Coordinator
- T. Dalpiaz, Manager, Nuclear Maintenance
- J. Fritzen, Supervisor, Modifications Installation
M. Golden, Supervisor, System Engineering Programs and Testing
- J. Gutshall, Supervisor, Valve Maintenance
J. Kenney, Supervisor, Nuclear Licensing
G. Kuczynski,
- J. Maertz, Senior Results Engineer
- D. McGann, Supervisor, Nuclear Compliance
- J. Meter, Compliance Engineer
G. Miller, Manager, Nuclear Technology
~ B. Saccone, Acting Manager, Nuclear Systems Engineering
J. Stefanko, Manager, Nuclear Fuels
- C. Smith, Senior Results Engineer
ni
1
rRe
1
mmis i n
- S. Barber, Senior Resident Inspector
- P. K. Eapen, Chief, Systems Section, DRS
- D. Galvin, DOE Intern
- R. Paroby, Co-op, Systems Section, DRS
- Designates
those in attendance at the exit interview on August 20, 1993.