ML17334A716
| ML17334A716 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 05/28/1998 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML17334A714 | List: |
| References | |
| 50-315-98-08, 50-315-98-8, 50-316-98-08, 50-316-98-8, NUDOCS 9806020122 | |
| Download: ML17334A716 (41) | |
See also: IR 05000315/1998008
Text
U.S. NUCLEAR REGULATORY COMMISSION
REGION III
Docket Nos:
License Nos:
50-315; 50-316
Report No:
50-315/98008(DRP); 50-316/98008(DRP)
Licensee:
500 Circle Drive
Buchanan, Ml 49107-1395
Facility:
Donald C. Cook Nuclear Generating Plant
Location:
1 Cook Place
Bridgman, Ml 49106
Dates:
March 13 through April 27, 1998
Inspectors:
B. L. Bartlett, Senior Resident Inspector
J. D. Maynen, Resident Inspector
Approved by:
Bruce L. Burgess, Chief
Reactor Projects Branch 6
'PBQ6Q20i22 98Q528
ADOCK 05Q00315
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EXECUTIVE SUMMARY
D. C. Cook Units 1 and 2
NRC Inspection Report No. 50-315/98008(DRP); 50-316/98008(DRP)
This inspection included aspects of licensee operations, maintenance,
engineering, and plant
support.
The report covers a 6-week period of resident inspection and includes follow up on
issues identified during previous inspection reports.
~Oerations
~
The inspectors determined that the continuous use procedure covering plant heatup for
Unit 2 was not known by the operators to be in effect, was not readily available, and was
not in use.
A violation for failure to follow procedure was identified (Section 01.2).
~
The licensee's procedure providing guidance for ventilation equipment required to support
Technical Specification (TS) equipment was weak.
The procedure addressed
a complete
failure of the ventilation equipment but failed to address degraded performance issues.
A
review of licensee documentation failed to identify any examples of inoperable TS
equipment as a result of the weak procedure (Section 01.3).
~
The licensee's investigation report into the exhaust manifold bracket failure on the 2 AB
emergency diesel generator (2 AB D/G) did not document the root cause for the missing
jam nuts on the
1 CD and 2 AB D/Gs. The inspectors concluded that appropriate
corrective actions for this significant condition adverse to quality could not be
implemented without an adequate
root cause determination.
A violation of
10 CFR Part 50, Appendix B, Criterion XVI,was identified (Section 07.1).
Maintenance
~
The inspectors determined that during the installation of a minor modification (MM) in
March 1997, the contract workers installing MM-438 on the
1 CD emergency diesel
generator loosened and improperly reinstalled the exhaust manifold bracket bolting
without the jam nuts as required by the job order.
This improper bolting configuration
could have led to a failure on that engine similar to the exhaust manifold bracket failure
which caused the 2 AB D/G to become inoperable for repairs.
The failure to install jam
nuts in accordance with the job order was a violation of TS 6.8.1 (Section M2.1).
~En ineerin
~
For those items sampled, the inspectors determined that the System Engineering Review
Board (SERB) and Restart Oversight Committee (ROC) appropriately determined whether
the item was required to be corrected prior to restart of the units.
However, the ROC
appeared to perform only a minimal review and assessment
on those items the SERB did
not recommend be corrected prior to restart (Section E7.1).
Plant Su
ort
~
The inspectors identified a non-safety-related
High Efficiency Particulate Absorber filter
installed in an unapproved manner in the steam generator storage building. Licensee
personnel failed to identify the improper installation even though multiple entries had been
made by radiation. protection personnel to perform routine surveys (Section R1).
)
Re ort Details
Summa
of Plant Status
Unit 1 remained in Mode 5, Cold Shutdown, during this inspection period. The unplanned outage
was in response to NRC and licensee concerns with the operability of the containment
recirculation sump and other engineering issues.
Unit 2 remained in Mode 5, Cold Shutdown, during this inspection period.
The unplanned outage
'as in response to NRC and licensee concerns with the operability of the containment
recirculation sump and other engineering issues.
I. 0 erations
01
Conduct of Operations
01.2
Control Room Procedure Use
Both Units
a.
Ins ection Sco
e 71707
The inspectors determined that the licensee had no operating procedure covering their
current Mode of operation (Mode 5- Cold Shutdown).
The inspectors evaluated the plant
configuration and compared the configuration to the plant operating procedures.
Documentation reviewed included:
~
Operations Head Instruction (OHI) - 2000, Revision 2, Operations Department
Guidance Policy
~
OHI - 2010, Revision 7, Operations Department Procedure Maintenance
~
02-Operations Head Procedure 4021.001.001,
Revision 20, Plant Heatup From
Cold Shutdown To Hot Standby
~
02-Operations Head Procedure 4021.001.004,
Revision 20, Plant Cooldown From
Hot Standby to Cold Shutdown
~
Plant Managers Instruction (PMI) - 2011, Revision 4, Procedure Use and
Adherence
~
Quality Assurance Program Description, Dated August 15, 1995
b.
Observations and Findin s
During a routine control room observation on April 26, 1998, the inspectors determined
that Unit 1 was being maintained in Mode 5 without utilization of a general operating
procedure.
Unit 2 was being maintained in Mode 5 through the use of the plant heatup
procedure (OHP 4021.001.001).
When questioned, the operators on Unit 2 did not know
which procedure they were in, but initiallythe operators thought that they were in the plant
JI
cooldown procedure (OHP 4021.001.003).
Following additional questioning from the
inspectors, the Unit 2 operators decided that they were in the plant heatup procedure
(OHP 4021.001.001).
The inspectors pointed out that the heatup procedure was required
to be used continuously when it was being performed, but the procedure was not out and
in use.
The Unit 2 operators then decided they were not in OHP 4021.001.001; the operators
were just in the normal operating procedure for the residual heat removal system.
However, for the performance of the Low Temperature Overpressure
Protection (LTOP)
Technical Specification (TS) surveillances, the operators were recording the required data
using the attachments
to the heatup procedure.
The next morning, the Assistant Shift Supervisor found the Unit 2
Procedure OHP 4021.001.001
on a back desk in the control room. The procedure
had not been closed out, had not been revision checked in over 3 months, and the night
shift operating crew had not known that it was still in use.
The failure to use the
appropriate procedure has, in the past, resulted in failures to comply with TS.
Technical Specification 6.8.1 requires, in part, that written procedures shall be established,
implemented and maintained covering the applicable procedures recommended
in
Appendix "A"of Regulatory Guide 1.22, Revision 2, February 1978.
Regulatory
Guide (RG) 1.33, Quality Assurance Program Requirements (Operation), Revision 2,
February 1978, Appendix A, recommended,
in part, that procedures
be written and
implemented governing the use of safety-related procedures.
Plant Managers's
Instruction 2011 was written in accordance with RG 1.33 to provide instructions on the use
of plant procedures.
PMI-2011, Revision 4, required, in part, that procedures designated
as "Continuous Use," shall be in use at the job site.
Procedure 02-OHP 4021.001.001,
Revision 20, was designated "Continuous Use," but it was not known by the Unit 2
operators to be in effect, and it was not in use.
The failure to follow PMI-2011 regarding
the use of "Continuous Use" procedures was a violation (50-316/98008-03(DRP)) of
Conclusions
The inspectors determined that the continuous use procedure covering plant heatup for
Unit 2 was not known by the operators to be in effect, was not readily available, and was
not in use.
A violation for failure to follow procedure was identified.
Ventilation Im act on Technical S ecification E ui ment
Both Units
Ins ection Sco
e 71707
During an assessment
of the operability status of the Unit 2 CD emergency diesel
generator (2 CD D/G), the inspectors questioned ventilation effects on D/G operability.
The inspectors reviewed the documentation listed below and interviewed licensee
personnel in an effort to ensure the licensee had declared the appropriate equipment
inoperable/operable
as required by TS.
~
12 - Plant Managers Procedure (PMP) 4030.001.001,
Revision 0, Impact of Safety
Related Ventilation on the Operability of TS Equipment
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~
Condition Report (CR) 98-1323, The preventive maintenance
to clean and inspect
the 2 CD D/G room exhaust fan exceeded its drop dead date
~
Reoccurring Job Order R0017464, 2-year preventive maintenance
to calibrate the
Unit 2 CD D/G overspeed indication and trip circuit
~
R0034692, 2-year preventive maintenance
to calibrate the Unit 2 CD D/G
overspeed indication and trip circuit
b.
Observations and Findin s
Procedure
12 PMP 4030.001.001, Attachment 3, stated, that if a D/G room exhaust fan
was incapable of moving air, the operators had a choice of either implementing the listed
compensatory measures
or declaring the associated
D/G inoperable.
The procedure
defined the phrase, "incapable of moving air," as, "... the system has failed and requires
repair.
Examples of this include: Collapsed ductwork which limits or prevents flow the
system...."
As noted in Inspection Report 50-315/92009, the reduction of air flow into and/or out of a
D/G room can affect the operability of the D/G. An exhaust fan that was degraded but still
moving air would meet literal compliance with Procedure PMP 4030.001.001, yet might not
meet design basis flow rates.
Under those conditions, the operability of the associated
D/G would be in question.
Other safety-related components. addressed
by Procedure PMP 4030.001.001, included
the essential service water (ESW) pumps, turbine driven auxiliary feedwater pumps
(TDAFWP), motor driven auxiliary feedwater pumps (MDAFWP), component cooling water
pumps (CCW), 4 kV switchgear rooms, 600 V transformer rooms, and control room
instrument distribution (CRID) inverter rooms. The ventilation requirements for these
rooms also included the phrase "incapable of moving air," yet, similar to the D/G rooms,
degraded ventilation flow could impact the operability of the affected safety-related
equipment.
The inspectors reviewed ventilation documentation for these systems but
found no instances of inoperable TS equipment.
The inspectors interviewed licensee personnel and determined that the procedure was
usually implemented during routine maintenance activities when it was obvious the fans
were not capable of moving air. Since the procedure wa's first written, there have been
several instances where fans were found inoperable, and the appropriate compensatory
measures
were established.
Conclusions
The licensee's procedure providing guidance for ventilation equipment required to support
TS equipment was weak.
The procedure addressed
a complete failure of the ventilation
equipment but failed to address degraded performance issues.
A review of licensee
documentation failed to identify any examples of inoperable TS equipment as a result of
the weak procedure.
fl
t,
07
Quality Assurance in Operations
~ 07.1
Investi ation'into the Unit 2 AB Emer enc
Diesel Generator Bracket Failure
71707
Ins ection Sco e.
On October 19, 1997, while running the 2 AB emergency diesel generator (2AB D/G) for
an 8-hour surveillance test, the flywheel end exhaust manifold bracket (bracket) failed.
The licensee investigated the event, and on December 30, 1997, the approved final
investigation report was issued.
The inspectors reviewed the licensee's investigation
report into the bracket failure. Specific details concerning the bracket failure are
discussed below in Section M2.1.
b.
Observations and Findin s
The licensee's investigation report stated that the probable cause of the 2 AB D/G bracket
failure was the loosening of the upper bracket bolt. An examination of the as-found
damage determined that the bolt did not have a jam nut installed as required by the
installation drawing. The licensee inspected the other three D/Gs and found that the
1 CD D/G bracket was also missing jam nuts. The licensee's investigators also
determined that the as-found bracket bolt torque values on the D/Gs were acceptable
on
all but the 2 AB D/G; thus, no past operability concerns were evident.
The licensee's investigators following up on the 2 AB D/G bracket failure did not reach a
conclusion about the root cause for the missing jam nuts on the
1 CD or 2 AB D/Gs.
However, by interviewing licensee staff members identified in the investigation report, the
inspectors determined that the upper bolt connection on the
1 CD D/G bracket had been
loosened and improperly reassembled
at the time of the modiTication, after the site QC
inspector verified proper assembly.
Based on this information, the inspectors concluded
that the failure to install jam nuts on the bolted connection was another example of the
contractor control problems which have been previously identified (Non-Cited
Violation 50-316/97024-05).
Although the
1 CD D/G bracket did not fail, missing jam nuts
were identified as the cause for the loose bolt on the similar 2 AB D/G bracket, leading to
its subsequent
failure; therefore, the missing jam nuts created a significant condition
adverse to quality. The cause of the missing jam nuts on the 2 AB D/G was
indeterminate; however, it appeared
possible that similar events had taken place on both
DIGs.
10 CFR Part 50, Appendix B, Criterion XVI, requires, in part, that measures
shall be
established to assure that conditions adverse to quality are promptly identified and
corrected, and that in the case of significant conditions adverse to quality, the measures
shall assure that the cause of the condition, is determined and corrective action taken to
preclude repetition. The identification of the significant condition adverse to quality, the
cause of the condition, and the corrective action taken shall be documented and reported
to appropriate levels of management.
The inspectors considered that the failure to
determine an adequate root cause for the missing
1 CD D/G jam nuts was a violation of
10 CFR Part 50, Appendix B, Criterion XVI (50-315/98008-02 (DRP)).
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Conclusions
The licensee's investigation report into the exhaust manifold bracket failure on the 2 AB
emergency diesel generator (2AB D/G) did not document the root cause for'the missing
jam nuts on the 1CD and 2AB D/Gs. The inspectors concluded that appropriate corrective
actions for this significant condition adverse to quality could not be implemented without
an adequate
root cause determination.
A violation of 10 CFR Part 50, Appendix B,
Criterion XVI,was identified.
08
Miscellaneous Operations Issues
08.1
Closed
Ins ection Follow-u
Item 50-315/96002-06
50-316/96002-06:
Licensee needs
to update Final Safety Analysis Report.
In April 1996, NRC inspectors determined that the
licensee had removed the recirculation sump level indicators and moved them to the
adjacent lower containment sump which is connected to the recirculation sump.
However,
Section 6.2 of the Updated Final Safety Analysis Report (UFSAR) stated that alarms and
redundant level indicators are provided in the containment recirculation sump.
The
inspectors reviewed the current UFSAR and found that Section 6.2 had been changed to
reflect the change in location of the sump level indicators.
This item is closed.
08.2
Closed
Ins ection Follow-u
Item 50-315/96004-06:
The licensee had determined that
the practice of having dual train Essential Service Water and Component Cooling Water
outages during a full core off-load exceeded
the licensing basis and that the UFSAR
contained errors which needed to be corrected.
Section E1.2.1D of Inspection
Report 50-315/97201; 50-316/97201 documented the NRC Architect Engineer inspection
team finding that a dual CCW/ESW train outage during refueling was inconsistent with the
plant design basis.
Licensee Event Report (LER) 50-316/97003 was issued to document
this condition. This issue will be tracked under the more recent LER and Inspection
Report 50-315/97201; therefore, this item is closed.
08.3
0 en
Licensee Event Re ort 50-315/98016-00:
On March 23, 1998, the licensee found that non-safety-related
cables were routed to
safety-related devices in the emergency D/G load shed circuitry. The cabling from the
load shed relays to the shunt trip coils on non-safety related 600-volt balance-of-plant
(BOP) loads was identified as BOP cable rather than safety-related cable.
The relays and
shunt trip coils are safety related.
Due to the plant design, some 600-volt non-safety related balance-of-plant (BOP) loads
are supplied by the safety related buses.
On a loss of offsite power event, these BOP
loads are supposed
to load shed from the buses to prevent overloading the D/Gs when
sequencing
loads back to the safety-related buses.
The licensee evaluated the cabling
configuration and determined that some BOP loads may not properly load shed, resulting
in potentially overloading one or more of the D/Gs.
Following this determination, the
licensee declared all four D/Gs inoperable and entered the TS action statements for
shutdown A.C. electrical sources.
Additionally, a 4-hour event notification was made to
the NRC.
The inspectors reviewed the licensee's actions and noted that many significant work
activities have been placed on hold because of the TS action statement requirements.
Licensee management
determined that developing a short-term and long-term solution to
the D/G cable issue was the highest priority item. Accordingly, the inspectors willcontinue
to followthe issues documented
in the LER.
08.4
0 en
Licensee Event Re ort 50-315/98017-00:
Debris recovered from ice condenser
potentially represents
unanalyzed condition. On March 27, 1998, the licensee reported to
the NRC that debris found during a partial inspection of the Unit 1 ice condenser could
potentially affect the ice condenser floor drains and containment recirculation.
Due, in
part, to this finding and recent NRC findings regarding the ice condenser (Inspection
Report 50-315/98005; 50;316/98005), the licensee decided to thaw both units'ce
condensers
and perform a complete inspection of the ice baskets.
The inspectors
followed the licensee's plans for thawing the ice condensers.
The licensee has begun preparations for thawing the Unit 2 ice condenser.
The
intermediate deck doors and the lower inlet door shock absorbers were removed and
stored in designated areas within the turbine building. Additionally, the licensee has
obtained temporary holding tanks to store the ice condenser runoff. The licensee
calculated the expected boron concentration in the ice melt and received permission from
the State of Michigan to release the ice melt to the environment.
However, due, in part, to operational limitations regarding the emergency diesel
generators (Section 08.3 above), a firm date for beginning the ice condenser thaw had not
been established
at the end of this report period. The inspectors willcontinue to followthe
issues documented
in this LER.
II. Maintenance
M1
Conduct of Maintenanc'e
M1.1
General Comments
Ins ection Sco
e 62707 and 61726
4
Portions of the following maintenance job orders, action requests,
and surveillance
activities were observed or reviewed by the inspectors:
A0159605
Unit 1 West Motor Driven AuxiliaryFeedwater Pump Ventilation
Supply - fire damper failed to drop during testing
A01 59685
Wallplates on outside of Auxiliary Building East Wall 609'ranebay
have come loose
A0159698
Troubleshoot the ground on the Unit 2 CD Diesel Generator Bus
C0044131
Calibration of the Unit 1 CD Diesel bearing temperature loops
C0038650
1-WMO-906, replace 16" Non-Essential Service Water Valve using
freeze seal
b.
Observations and Findin s
The inspectors observed that the workers followed their procedures and appropriately
documented the required information. A0159685 was identified by radiation protection
workers performing followup to an unidentified and unusual noise.
Control room personnel
promptly responded and ensured that any loose building panels did not threaten off-site
power supplies and electrical transformers.
M2
Maintenance and Material Condition of Facilities and Equipment
M2.1
Closed
Unresolved Item 50-315/97018-06
50-316/97018-06:
Diesel generator exhaust
manifold brackets (both units). On October 19, 1997, while running the 2 AB D/G for an
8-hour surveillance test, the flywheel end exhaust manifold bracket failed. An unresolved
item was opened pending a review of the licensee's investigation into the root cause of the
bracket failure.
Ins ection Sco
e 62707
The licensee completed the investigation into the root cause of the bracket failure. The
inspectors reviewed the licensee's findings and the following documents:
12-MM - 438, "Replace the emergency diesel generator exhaust manifold structure
supports
12-DCP-861, "Enhancement of the bracket tab of flywheel end support assembly of
exhaust manifold for Emergency Diesel Generators"
- 12 Construction Head Procedure (CHP) 5021.MCD.001, Revision 2, "Fabrication
and Installation of Safety-related/Safety
Interface Component Supports, Hangers,
and Restraints"
12-Plant Manager's Procedure 7030.INV.001, Revision 0, "Condition Investigations
and Approvals"
Condition Report (CR) 97-2904, During the eight-hour surveillance test of the
2 AB D/G, the generator end exhaust manifold support bracket broke.
Job Order C18424, Replace emergency diesel generator exhaust manifold
supports,
1 CD D/G
Job Order C19480, Replace emergency diesel generator exhaust manifold
supports, 2 AB D/G
Drawing 01-A-EQS-197, "Unit No.
1 AB and CD Diesel Support Arrangement"
Drawing 01-A-EQS-198, "Unit No.
1 AB and CD Diesel Manifold - Exhaust
Conversion"
Drawing AEP-G13725-0, "Unit No. 2 AB and CD Diesel Support Arrangement"
I
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Drawing AEP-G13726-0, "Unit No. 2 AB and CD Diesel Manifold - Exhaust
Conversion"
Observations and Findin s
The licensee's investigation into the bracket failure identified that both the
1 CD D/G and
the 2 AB 0/G flywheel end exhaust manifold brackets were missing jam nuts. The
investigation further concluded that the probable cause of the bracket failure on 2 AB D/G
was the loosening of the upper bracket bolt. However, the licensee's investigation was
inconclusive regarding the reason that the jam nuts were missing on the two diesels.
The
system engineer stated that no maintenance
had been done on the
1 CD D/G or 2 AB D/G
which would have required loosening the bracket bolts or removal of the exhaust manifold
end cover (end cover).
The end cover needed to be removed to allow access to the upper
bolt. Thus, the system engineer concluded that the jam nuts had been missing since the
time of the minor modification installation, in March 1997.
The inspectors interviewed the site quality control (QC) inspector who observed the bolt
assembly on the
1 CD 0/G on March 11, 1997.
The site QC inspector recalled that the
bracket bolts were properly torqued and the jam nuts were present; however, the end
cover was not yet in place.
Additionally, the site QC inspector stated that the two bracket
bolts were installed with the bolt heads on opposite sides of the bracket, as shown on the
design drawing. The site QC inspector also recalled that the contractor employees who
were installing the minor modification were having trouble with the re-installation of the
end cover.
The inspectors then interviewed the engineers who inspected the 1CD D/G after the
2 AB D/G bracket failed. The engineers stated that the
1 CD D/G bracket bolts were found
with the bolt heads on the same side of the bracket and that no jam nuts were installed.
Additionally, the engineers stated that the end cover was found in physical contact with the
end of the upper bolt. This condition would have prevented an installed jam nut from
falling offof the upper bolt even if it had come loose.
Therefore, the engineers concluded
that the jam nut was not installed at the time the end cover was replaced.
Based on the information presented
in the interviews, the inspectors concluded thai the
contract workers installing MM-438 on the 1CD D/G had loosened and reinstalled the
upper bolt in the opposite direction without the jam nut after the site QC inspector verified
proper assembly.
The upper bolt may have been reversed to allow the end.cover to fit
properly. While the reversal of the bolt was allowed by the installation drawing, a QC
inspector would have been required for re-verification of the connection torque. The site
QC inspector stated that neither he nor any other QC inspector were asked to verify the
bolt connection after the initial verification. Although the missing jam nuts on the
1 CD D/G bracket connections had not yet led to a failure of the exhaust manifold bracket
on the 1CD D/G, the risk of a failure similar to the failure which occurred on the 2 AB D/G
was high.
The site QC inspector who verified the bolt assembly on the 2 AB D/G was no longer a
licensee employee, so the inspectors were unable to verify the initial bolting configuration
on the failed bracket.
However, the MM-438 paperwork indicated that the 2 AB 0/G
bracket connection had also been properly made up and verified. The inspectors
interviewed the engineer who inspected the 2 AB D/G bracket after it failed. The engineer
11
stated that it was unlikely that a properly installed jam nut would come loose, and no loose
jam nuts were found on or near the 2 AB D/G. Additionally, the as-found damage to the
upper bolt indicated that the jam nut was not present;
therefore, the engineer concluded
that the jam nuts were not installed on the bracket prior to the failure. Although the
inspectors were unable to draw a definite conclusion about when or why the jam nuts were
removed from the 2 AB D/G bracket, it was possible that, similar to the
1 CD D/G bracket,
the bolted connections were loosened and incorrectly reassembled
to allow the 2 AB D/G
end cover to fit properly.
'he inspectors walked down all four D/Gs and verified the bolting configuration with the
design drawings.
The inspectors also reviewed the examination results and as-left torque
values documented
in the licensee's investigation and identified no discrepancies.
Technical Specification 6.8.1 requires, in part, that written procedures shall be established,
implemented and maintained covering the applicable procedures recommended
in
Appendix A of RG 1.22, Revision 2, February 1978.
Regulatory Guide 1.33, Quality
Assurance Program Requirements (Operation), Revision 2, February 1978, Appendix A,
recommended,
in part, that maintenance that can affect the performance of safety-related
equipment should be properly pre-planned and performed in accordance with written
procedures,
documented instructions, or drawings appropriate to the circumstances.
Job
Order C18424 was written in accordance with RG 1.33 to provide instructions for installing
12-MM-438 on the
1 CD D/G.
Job Order C18424 required, in part, that the exhaust manifold brackets be installed in
accordance with the appropriate drawings.
Drawing 01-A-EQS-197 indicated that the
bolted connections included jam nuts.
Job Order C18424 also required, in part, that QC
be contacted to verify proper connection configuration and torque.
The failure to install
12-MM-438 on the
1 CD D/G in accordance with Job Order C18424 was a violation
(50-315/98008-01) of TS 6.8.1.
Conclusions
The inspectors determined that during the installation of a minor modification in
March 1997, the contract workers installing MM-438 on the
1 CD emergency diesel
generator loosened and improperly reinstalled the exhaust manifold bracket bolting without
the jam nuts as required by the job order. This improper bolting configuration could have
led to a failure on that engine similar to the exhaust manifold bracket failure which caused
the 2 AB D/G to become inoperable for repairs.
The failure to install jam nuts in
accordance with the job order was a violation of TS 6.8.1.
M2.2
Closed
Ins ectionFollowu
Item 50-316/97018-05:
Unit2ABdieselgeneratorpoor
material condition. The 2AB D/G had been placed on an accelerated
surveillance
frequency following a second valid test failure in August 1997.
Condition Report 97-2810
was issued on October 14, 1997, to document the third functional failure of the 2AB D/G
over a 2-year period. The 2AB D/G was placed in Maintenance Rule [10 CFR 50.65]
Category (a)(1) on December 4, 1997.
The inspectors discussed the monitoring plan with
the system engineer and concluded that the 2 AB D/G goals were commensurate
with its
safety significance and met the intent of Regulatory Guide 1.160, "Monitoring the
Effectiveness of Maintenance at Nuclear Power Plants." This item is closed.
12
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M2.3
Closed
Ins ection Follow-u
Item 50-315/94014-02
50-316/94014-02:
Abilityto maintain
negative pressure
in the auxiliary building. During a tour of the auxiliary building, the
inspectors found the door (1-DR-AUX-385) from the Unit 1 Quadrant 2 room to the non-
essential service water (NESW) valve gallery open.
The inspectors questioned whether
having this door open would prevent the ventilation system from developing a negative
pressure in the Quadrant 2 room. With this door open, the Quadrant 2 room
communicated directly with the area outside the auxiliary building. A similar condition
existed for the Unit 2 Quadrant 2 room (2-DR-AUX-386).
The licensee assessed
the original configuration and found that each unit's Quadrant 2
room, NESW valve gallery, electrical tunnel, and east main steam valve enclosure were
included as part of a single radiation zone on the post accident radiation zone maps.
Based on the maps and the physical configuration of the containment penetrations in
these area, the licensee concluded that unmonitored radiation releases
from these areas
were not likely. Additionally, the licensee found that no high energy lines had postulated
breaks within the Quadrant 2 rooms.
Therefore, the assessment
concluded that the
original configuration was acceptable.
The inspectors reviewed the assessment
and had
no questions.
However, due to the potential for recirculation water from the containment sump to flow
through the boron injection tank (BIT) in some post accident scenarios,
the licensee
decided to include the Quadrant 2 rooms in the auxiliary building pressure boundary
'ABPB). These scenarios postulated elevated activity inside the Quadrant 2 room, in the
area near the BIT. Attachment
1 to Plant Manager's Procedure 4030.001.002,
"Administrative Requirements for Ventilation Boundary and High Energy Line Break
Barriers," was revised, adding both units'uadrant 2 rooms to the ABPB. Doors
1-DR-AUX-385 and 2-DR-AUX-386 were closed, and the doors to the general auxiliary
building were opened for ventilation reasons.
The inspectors reviewed the APBP, high
energy line break, and fire protection functions for both units'uadrant
2 room doors and
compared the door requirements to the updated final safety analysis report.
No
discrepancies were identified; therefore, this item is closed.
M4
Maintenance Staff Knowledge and Performance
M4.1
Closed
Ins ection Follow-u
Item 50-315/96006-13
50-316/96006-13:
Weakwork
practices observed during new fuel receipt.
Inspection Report 50-315/96003;
50-316/96003 documented weak work practices during new fuel receipt.
In Inspection
Report 50-315/97002; 50-316/97002, the NRC documented additional procedural
deficiencies in the licensee's receipt of new fuel assemblies which resulted in several
violations of NRC requirements.
The licensee conducted an in-depth review and upgrade
to the process of receiving new fuel, and on August 14, 1997, the licensee commenced
fuel receipt in preparation for a Unit 2 refueling outage.
Inspection Report 50-315/97015;
50-316/97015 documented this new fuel receipt inspection and closed the procedural
violations. The inspectors had no new concerns; therefore, this item is closed.
Miscellaneous Maintenance Issues
M8.1
Closed
Licensee Event Re ort 50-315/95010-00:
Inadequate Communication Results in
Unexpected Engineered Safety Features Actuation. On October 20, 1995, while Unit 1
was shutdown, an unexpected reactor trip signal was generated.
The trip signal was
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caused by instrumentation and control (l&C) personnel repairing intermediate range
Neutron Flux Detector 1-NRI-36. The reactor trip breakers opened, but since the unit was
shutdown no rod movement occurred.
No other plant equipment was affected.
This event
was discussed
in Inspection Report 50-315/95012; 50-316/95012.
The inspectors
considered the licensee's response to this event to be timely and thorough.
The licensee
event report documented no new issues; therefore, this licensee event report is closed.
M8.2
Closed
Violation 50-315/96009-03
50-316/96009-03:
Inadequate Maintenance Rule
Reliability Monitoring Criteria
The licensee has demonstrated
through the use of a sensitivity study that the demand
failure and availability assumptions
in their probabilistic risk assessment
were preserved.
The demonstration was performed by substituting the maintenance
rule functional failures
divided by the estimated number of demands
in place of the probabilistic risk assessment
demand failure data and the maintenance
rule unavailability performance criteria in place
of the probabilistic risk assessment
unavailability probability.
The licensee approach included several conservative assumptions which included the
following:
The licensee's maintenance
rule program considered functional failures that are
riot modeled in their probabilistic risk assessment.
For example, a normally open
motor operated valve that fails a stroke time test would be considered a
maintenance
rule functional failure; however, this valve would not be modeled in
the probabilistic risk assessment
since it is normally open.
2.
The sensitivity study considered degradation of functions where the performance
criteria were more conservative that the probabilistic risk assessment
assumptions.
3.
The sensitivity study assumed that every function degrades simultaneously.
There
is an extremely low probability. that this would ever occur.
Using this approach, the licensee calculated a core damage frequency of 1.25E-4 which is
76 percent higher than their baseline core damage frequency of 7.09E-5.
This is a
relatively small increase in core damage frequency.
Given the conservatism
in the sensitivity study and the relatively small increase in core
damage frequency, the licensee has successfully demonstrated
that their performance
criteria is commensurate
with safety and has preserved their probabilistic risk assessment
assumptions.
This violation is closed.
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If
III. En ineerin
E7
Quality Assurance in Engineering Activities
E7.1
En ineerin
Performance
In Restart Activities Both Units
Ins ection Sco
e 37551
The inspectors assessed
selected licensee meetings on restart activities.
Observations and Findin s
During this inspection period significant licensee engineering resources were spent on the
implementation of the restart plan and performing system walk downs.
The inspectors
observed selected System Engineering Review Board (SERB) and Restart Oversight
Committee (ROC), which oversees
the SERB.
The SERB performed the initial review of
the system walk down results.
The ROC then performed an additional review in an
oversight role. The inspectors evaluated selected walk down items.
For those items
sampled, the inspectors concluded that the SERB and ROC appropriately determined
whether the item was required to be corrected prior to restart of the units. However, the
inspectors
observed that the ROC members concentrated
on those items which were
recommended
to be corrected prior to restart by the SERB. Minimal review and
assessment
were performed on those items which the SERB did not recommend for
restart.
Some members of the ROC did question some of the items not-recommended
to
be corrected prior to the restart by the SERB; however, the questions were few and widely
separated.
During inspector observations of selected SERB meetings, licensee personnel carefully
evaluated each item against the Board's understanding of the item's effect on the system
to help decide ifthe item required correction prior to restart.
During a Senior Management
Review Team (SMRT), contractor personnel presented their observations of the BERB to
licensee management.
The most significant comment was that the contractors observed
little guidance being provided from the SERB to the engineers performing the system walk
downs.
Licensee management
told the contractors that they were still in the process of
learning how to perform the walk downs and were making improvements.
In addition,
licensee management
stated that at the end of the system walk downs they would assess
the need to re-perform the any system walk downs.
The inspectors noted that, at the time
of the licensee management's
statement,
a little over half of the system walk downs were
completed.
Additional NRC assessments
will be performed; however, the nature and extent of the
NRC assessments
will be guided by Manual Chapter 0350, Staff Guidelines for Restart
Approval, D. C. Cook specific plan.
Conclusions
For those items sampled, the inspectors determined that the System Engineering Review
Board (SERB) and Restart Oversight Committee (ROC) appropriately determined whether
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the item was required to be corrected prior to restart of the units. However, the ROC
appeared
to perform only a minimal review and assessment
on those items the SERB did
not recommend for restart.
E8
Miscellaneous Engineering Issues
E8.1
Closed
Violation 50-316/95013-02:
Missed surveillance due to misapplication of
Regulatory Guide.
On December 29, 1995, the 2 CD D/G failed to start during a post
maintenance
test.
The system engineer did not use RG 1.108, as specified in TS 3.8.1.1,
to determine whether the 2 CD D/G start failure was valid. The subsequent
erroneous
decision; based on RG 1.9, that the failure was not valid resulted in a failure to test the
2 CD D/G at the increased frequency as specified in TS 3.8.1.1.
The inspectors interviewed the system engineer and reviewed the classification of start
demands for all four D/Gs since December 1995.
The licensee's reply to this violation
stated, in part, that a TS amendment would be submitted to allow the use of RG 1.9 in
place of RG 1.108 for determination of valid tests; however, the TS has not yet been
amended to allow the use of RG 1.9. The inspectors determined that all subsequent
D/G
start demands have been appropriately classified in accordance with RG 1.108. The
inspectors also found that the D/G surveillance tests have been performed at the proper
frequency; therefore, this violation is closed.
IV. Plant Su
ort
R1
Radiological Protection and Chemistry Controls (71750)
During a routine tour of buildings outside of the protected area, the inspectors observed a
non-safety-related filterinstalled in a questionable manner.
The storage building for the
used Unit 2 steam generators contained a high efficiency particulate absorber (HEPA) filter
that was secured in place with duct tape and wire. The filterwas on the end of a
10" diameter pipe that was designed to hold a HEPA filter; however, the filterwas not
installed in accordance with the drawing.
The purpose of the filteiwas to ensure that any air movement out of the building was
uncontaminated.
The jury-rigged filterwould have performed the intended function;
however, the improper installation made it more subject to damage.
The inspectors noted
that the. filter had been in place since approximately 1988 with four or more inspections
each year of the facility by licensee personnel, yet the improper HEPA filter installation had
not been questioned.
Following identification by the inspectors,
a condition report was issued and an action
request was written to restore the filter to its as designed configuration.
No other discrepancies
were noted.
S1
Conduct of Security and Safeguards Activities (71750)
During a routine tour of the auxiliary building the inspectors observed a security fighting
position that was blocked by material stored in the area.
The stored material would hinder
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the view of security personnel using the position. The inspectors informed the security
shift captain who began an evaluation.
The inspectors were informed that the fighting
position was no longer used, that security personnel had been trained to use new position,
and that the security personnel procedures had been altered to reflect the new position.
The licensee noted that the Security Deployment Plan had not been modified to reflect the
new position. The inspectors verified that the licensee initiated a revision to the
Deployment Plan and that the plan was for internal use only and was not required to meet
NRC regulations.
No other discrepancies
were noted.
F1
Control of Fire Protection Activities (71750)
During normal resident inspection activities, routine observations were conducted in the
area of fire protection activities using Inspection Procedure 71750.
No discrepancies were
noted.
X1
Exit Meeting
The inspectors presented
the inspection results to members of the licensee management
at the conclusion of the inspection on April 27, 1998. The licensee had additional
comments on some of the findings presented.
No proprietary information was identified by
the licensee.
~
Additional comments re ardin
Section E7.1
En ineerin
Performance
In Restart
Activities
Regarding the inspectors'omments
that at the end of the system walkdowns, they
would assess
the need to re-perform the system walk downs first performed, the
head of the SERB, Mr. Don Hafer, stated some engineers had already been sent
back out into the field as a result of lessons learned.
When requested
to give
examples,
Mr. Hafer stated that some systems had been walked down by-
individual operators, maintenance
personnel, and engineers instead of the required
team's.
Those systems had been walked down again using teams.
Mr. Hafer also
stated that in at least one example, one system was walked down again due to the
low number of findings.
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PARTIAL LIST OF PERSONS CONTACTED
Licensee
¹M. Ackerman, Licensing Manager
¹K. Baker, Manager, Production Engineering
¹P. Barrett, Manager of Protection Assurance
¹A. Blind, Vice-President Engineering
¹S. Brewer, Manager of Regulatory Affairs
¹D. Cooper, Plant Manager
¹S. Delong, Management Information
¹MB. Depuydt, Nuclear Licensing
¹R. Gillespie, Operations Superintendent
¹MB. Greendonner,
Plant Protection
¹D. Hafer, Manager, Plant Engineering
¹D. Morey, Corrective Action Supervisor
¹D. Noble, Radiation Protection Superintendent
¹F. Pisarsky, Supervisor, Mechanical Component Engineering
¹T. Postlewait, Manager, Design Engineering
¹J. Sampson, Site Vice-President
¹P. Schoepf, Supervisor, Safety-Related Mechanical Systems
¹M. Stark, Engineering Supervisor
¹J. Wiebe, Performance Assurance Manager
¹B. Burgess, Branch Chief, Region III
¹Denotes those present at the April27,'998, exit meeting.
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INSPECTION PROCEDURES USED
IP 61726
IP 71707
IP 92700
On-site Engineering
Surveillance Observations
Maintenance Observation
Plant Operations
Plant Support Activities
- Onsite Review of LERs
ITEMS OPENED
50-315/98008-01
50-315/98008-02
ITEMS OPENED, CLOSED, AND UPDATED
Failure to install jam nuts on 1 CD D/G exhaust manifold
bracket as required by modification drawing
Failure to determine adequate
root cause for missing jam
nuts on
1 CD D/G
50-316/98008-03
ITEMS CLOSED
50-315/94014-02
~ 50-316/94014-02
50-315/95010-00
50-316/95013-02
50-315/96002-06
50-316/96002-06
50-315/96004-06
50-315/96006-13
50-316/96006-13
50-315/96009-03
50-316/96009-03
50-316/97018-05
50-315/97018-06
50-316/97018-06
Failure to follow procedure when utilizing a continuous use
,
procedure to operate in Mode 5
IFI
Abilityto maintain negative pressure
in the auxiliary
building
LER
Inadequate communication results in unexpected
actuation
Missed surveillance due to use of wrong Regulatory Guide
IFI
Licensee needs to update final safety analysis report
IFI
Dual train ESW and CCW outages
IFI
Weak work practices observed during new fuel receipt
Inadequate maintenance
rule reliability monitoring criteria
IFI
Unit 2 AB diesel generator poor material condition
Diesel generator exhaust manifold brackets
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ITEMS UPDATED
50-315/98016-00
50-315/98017-00
LER
Non-safety-related cables routed to safety related equipment
LER
Debris recovered from ice condenser potentially represents
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LIST OF ACRONYMS
ABPB
AEP
bcc
BIT
CFR
.CHP
CR
GRID
DCC
D/G
EDT
IR
JO
LER
Ml
MM
NRC
OHI
PMI
SERB
SMRT
SSPS
S/G
AuxiliaryBuilding Pressure
Boundary
American Electric Power
Balance of plant
blind carbon copy
Boron Injection Tank
carbon copy
Component Cooling Water
Code of Federal Regulations
Construction Head Procedure
Condition Report
Control Room Instrument Distribution
Donald C. Cook
Division of Reactor Projects
Demonstration Power Reactor
Eastern Daylight Time
Engineered Safety Feature
Essential Service Water
Inspection Report
Job Order
Licensee Event Report
Loss of Coolant Accident
Low Temperature Overpressure
Protection
Minor Modification
Non-Cited Violation
Non-Essential Service Water
Nuclear Regulatory Commission
Nuclear Reactor Regulation
Operations Head Instruction
Plant Manager's Instruction
Plant Manager's Procedure
Public Document Room
Quality Control
Regulatory Guide
Restart Oversight Committee
System Engineering Review Board
Senior Management Review Team
Senior Reactor Operator
Solid State Protection System
Surveillance Test Procedure
Updated Final Safety Analysis Report
Unresolved Item
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