ML20198M280
| ML20198M280 | |
| Person / Time | |
|---|---|
| Site: | Waterford  |
| Issue date: | 01/12/1998 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| Shared Package | |
| ML20198M274 | List: |
| References | |
| 50-382-97-24, NUDOCS 9801200061 | |
| Download: ML20198M280 (22) | |
See also: IR 05000382/1997024
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ENCLOSURL2 ;
U.S. NUCLEAR REGULATORY COMMISSION
REGION IV
Docket No.:- 50 382 :
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License No.: NPF 38
Report No.: i
50 382/97 24
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Licensee: Entergy Operations, Inc.
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Facility: Waterford Steam Electric Station, Unit 3
Location: Hwy.18 ,
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Killona, Louisiana
Dates: November 2 through December 13,1997
Intpectoro: J. M. Keeton, Resident inspector
G. A. Pick, Senior Project Engineer
C. E. Johnson, Reactor inspector
Accompanied By: J. C. Edgerly, Resident Inspector Trainee
Approved By: P. H. Harrell, Chief, Project Branch D
ATTACHMENTS: Supplemental inforrnation j
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EXECUTIVE SUMMAllY
Waterford Gteam Electric Station, Unit 3
NRC inspection Report 50-382/97 24
This routine, announced inspection included aspects of operations, maintenance,
engineerint,, and plant support activities. The report covers a 6 week period of resident
inspection.
DDDLEtlDDS
- A violation resulted from the failure to provide adequate postmaintenance testing
instructions (EA 97 588) (Section 02.1).
- Dirt and debris in the reactor auxiliary building (RAB) drains had the potential for
adversely affecting safety equipment and no progrt.m existed for routinely cleaning
the drains. This issue remains unresolved (Section 02.2).
- The failure to complete the surveillance of the flow low bypass prior to entering
Mode 2 in 1989 resulted in a violation of Technical Specification 4.3.1.2. This is a
noncited violation (Saction 08.5).
Maintenance ,
- Replacement of the pressure analog comparator card was performed in a
professional manner, with good supervisory oversight (Section M1.2).
The maintenance rule program for the process radiation monitor system was
appropriately implemented (Section M2.2).
Engiacering
The f ailure to account for recirculation flow to a tank resulted in a nonconservative
determination for the onset of vortexing r. i resulted in a violation (EA 97 587) ,
(Section E1.1).
- The engineering evaluation for the single component failure effects on the
condensate storage pool (CSP) was thorough, timely, and addressed the issues
appropriately (Section E2.1).
Plant SuoDQLt
- The inspector observed good command and controlin the control room simulator
and technical support center during the graded emergency exercise (Section P1.1).
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Report Details
Summarv of Plant Statt,t3
During this inspection period, the plant operated at essentially 100 percent power.
LOAttall0Da
01 Conduct of Operations
01.1 General C mments
9 1717071
s The inspectors perMrmed frequent reviews of ongoing plent evaluations, control
room panel walkdowns, and plant tours. Observed activities were performed in a
rnanner consistent with safe operation of the facility. The inspectors also observed
several shif t turnovers and daily routine shif t activities. The inspectors observed
operators using self checking and peer checking techniques when manipulating
equipment. Three way communications were consistently used by the operators
within the control room and in external communications with equipment operators
and maintenance personnel.
02 Operational Status of Facilities and Equipment
02.1 Comoonent Coolina Water (CCW) Valve to Containment Fan Coolers inonerable for
an Extended Period
a. Insoection Snone (71707)
The inspectors reviewed the circumstances related to Valve CC 835B, CCW flow
control for Containment Fan Coolers B and D, being found gagged in a partially shut
position. The inspectors interviewed members of the licensee staff, reviewed
documentation, and reviewed the corrective actions taken by the licensee to address '
this concern.
b. Qhigtyations and Findinos
On October 17,1997, operators performed the quarterly inservice testing stroke
test for Valve CC 835B in accordance with Procedure OP 903118, "Prirnary
Auxiliaries Quarterly IST Valve Tests." Valve CC 835B controls the CCW flow to
Containment Fan Coolers B and D. During the test, an operator stationed at the
valve discovered that the mechanical gag for Valve CC 835B was partially engaged,
which restricted valve travel to only about 80 percent open. Control room personnel
directed the operator to adjust the gagging device and satisf actorily retested the
valve to verify it opened 100 percent. Operatior.s personnelinitiated Condition
Report (CR) 97 2450 to investigate thia event.
The licenlee subsequently determined that the valve had been gagged fully shut
during a,t operator maintenance on September 9,1997 (39 days previously). Tne
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gag should have been fully disengaged by operations personnel after the l
Instrumentation and control (l&C) technicians completed the work activities.
Technical Specification Surveillance Requirement 4.0.2.2.b.3 requires that each
cooling water control valve actuates to its fully open position on a safety injection
actuation signal test signal. As a result of Valve CC 835B being gagged so it would
only open to 80 percent, the valve f ailed to meet the action requirements of *
Technical Specification 3.6.2.2 for an operable system. The licensee performed an
eva!uation of the as founo position of Valve CC 835B with respect to as found flow
rates to the containment f an coolers. Based on the evaluation, the licensee
determ'ned that the valve was technically inoperable since it was not fully open;
however, the system remained functional since the system flow rates were well
above that required for th9 system to perform its design basis function.
The inspectors independently reviewed the evaluation completed by the licensee.
Based on this review, the inspectors established that adequate flow would have
been available to each fan cooler to provide its safety function even though
Valve CC 8358 was restricted to 80 percent open. Valve CC 835B is an 8 inch
butterfly valve with flow characteristics sut.h that 100 percent flow !s obtained with
the valve at 40 percent open. Observed flow through each fan cooler with the valve
at approximately 80 percent open was about 1450 ppm. The minimum flow :
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requirement is 1200 gpm. The inspectors determined that, although the valve could
not meet the specific requirements of Technical Specification 4.6.2.2.b.3, the safety
significance of the valve only opening 80 percent was minimal since the system
remained fully functional.
The inspectors reviewed Work Authorization (WA) 01163329, which authorized
replacement and adjustment of the air regulator for Valve CC-835B on September 9.
It was noted that the WA provided instructions for the I&C technicians to disengage
the gag; however, the instructions for performance of the postmaintenance test
(i.e., verify the gag was fully removed) were inadequate because the instrt.:tions did
not require Valve CC 8358 to be stroked opened and closed to ensure the gag had-
been fully disengaged. Technical Specification 6.8.1 raquires that instructions be
provided for performance of maintenance on safety relited systems. The failure to
provide adequate instructions for postmeintenance tes'ing of Valve CC 8358 is a
violation (50-382/9724 01).
The inspectors reviewed the actions taken by the licensee to bound the extent of
this problem. A search of the CR data base from April 1,1997 (beginning of the
refueling outage), un:il the present was performed to determine if any valves had
l failed the Inservice test stroke test. The licensee identified that only Valve CC-8358
had maintenance performed without the appropriate retest.
The licensee issued LER 97 025 to document this event and to provide the
4 corrective actions taken to address this issue. A discussion of the review performed
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of the licensee's impiementation of the corrective actions is provided in Section
08.6 of this report. 2
c. Conclusions
A violation for inadequate postmaintenance instructions was identified.
02.2 Dirt and Debris in RAB Floor Drains
a. Insoection Scooe (717071
The inspectors toured the RAB for the purpose of inspecting floor drains for dirt and
debris to verify the drains were able to parform their intended function,
b. Observations an 1 Findio.g3
On November 4,1997, during a tour of the RAB, the inspectors noted that the floor
drains on the + 21.fciot level contained enough dirt and oebris to potentially cover
. any open drain path. This prompted inspection of all floor drains in the RAB,
including all safety related pump rooms. Most of the floor drains in the RAB
contained dirt, paint chips, and other det,ris, which covered the acreens on the drain
insrats.
The inspectors notified the shift superintendent, who immediately notified the
radiation protection field support supervisor and wrote CR 97 2544. The inspectors
asked if a routine surveillance existed for verification that the floor drains were
functional and established that a program for periodically cleaning the drains did not
exist.
Immediate attention was given to the drains in the diesel ganerator rooms and the
safety related pun.p rooms. The screens were cleaned and ilow paths were verified
to be open. Other drains in the RAB were also suosequently cleaned.
As of the end of this inspection, the licensee had not completed long term corrective
actions associated with the CR, nor had an evaluation been completed to determine
the impact on plant operations for the clogged drains. This issue is unresolved
pending review of the long term actions to resolve this issue (50 382/9724 02).
c. Conclusions
~ A condition existed in the RAB that had the potential for adversely affecting safety.
equipment. This condition should have been identified by operators during routine
tours.
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08 Miscellaneous Operations issues (92901)
08.1 CasediLER 50-382/98 004: Failure to meet intent of Technical Specification
surveillance because of inadequate corrective actions.
The LER describes the same condition as Enforcement
Action (EA) 50 382/96-025/01013, which is discussed in Section 08.3 of this
report. Since the corrective actions for that violation were satisf actory, this item is
considered closed.
08.2 Coled)LER 50 382/96-006: Reactor trip following a failure of the control element
drive motor / generator (M/G) set voltage regulator
A reactor trip occurred on May 17,1996, with the plant operating at 100 percent
power. The trip resulted from the low of both M/G sets because the M/G Set A
voltage regulator failed. The licensee determined that heat related aging caused the
failure.
The inspectors verified that the following corrective actions had been completed:
(1) imolemented a stand off resistor modification to improve the heat dissipation of
the M/G voltage regulators; (2) developed repetitive tasks to replace the M/G
over voltage relays at 10 year intervals; and (3) initiated a station modification
request to evaluate annunciator system improvements for a tripped M/G set. The
licensee will assess whether any modification would improve syc. tem reliability for
high voltage conditions and to reduce operating temperature in the M/G set local
control panel.
Based on the reviews performed by the inspectors, it was concluded that the
licensee had taken the appropriate actions to address this issue.
08.3 (Closed) EA 50-382/96 025/01013: Failure to preclude the development of voids in
the Auxiliary component cooling water system.
This violation resulted from f ailure to identify the root cause and take adequate
corrective actions on numerous occasions from 1994 to 1996 to eliminate volds in
the Auxiliary component cooling water system. After the NRC expressed concern
with this deficiency, the licensee initiated a root cause analysis and identified
comprehensive corrective actions. The licensee attributed the root cause to air
intrusion through relief valves and column separation.
The inspectors confirmed that the licensee implemented the following immediate
corrective actions: (1) relocated all system engineering planning functions to the
maintenance planners; (2) assigned responsibility for performing ultrasonic testing of
hydraulic piplag to quality assurance; (3) revised Procedure UNT 005-012
" Repetitive Task Identification," to ensure a planner must create and oversee
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repetitive tasks, ensure that tasks must be accepted prior to beirig assigned, and (
address the planning function; (4) reviewed for any other late repetitive tasks;
(5) disseminated to maintenance planners, operations, system engineering, and
quality assurance personnel, lessons learned from this experience; (6) revised
Procedure W2.501, * Corrective Action," to ensure that root cause analyses and the
recommended corrective actions are presented to the Condition Review Board for
approval; and (7) evaluated the open CR to determine whether additionalinterim
corrective actions were required.
The inspectors verified that the licensee completed the following corrective actions
to address generic consequences: (1) enginacts evaluated susceptibility of other
safety related systems to fluid transients and assessed adequacy of fill and vent
procedures; (2) operations and operational experience engineering completed
separate, independent reviews of surveillance procedures in order to identify
workarounds; and (3) an outsido regency completed a corrective action process
audit.
The licensee identified that three surveillance procedures contained test
arrangement that required engineering review to eliminate the potential
workarounds. As of the end of this inspection period, the licensee indicated that
engineering requests would be initiated to ensure a detailed review would be
completed. The items requiring review included: (1) evaluating whether the all
emergency feedwater (EFW) flow paths must be velified through both sets of valves
for each steam generator, (2) testing of Valves CVC 216A(B), pressurizer auxiliary
spray isolation, not performed because a note indicates valves cannot close against
reactor coolant system pressure, and (3) evaluating the reason for closing
Valves CC 125A,125B, and 125AB, CCW discharge isolation, prior to securing the
pump.
The inspectors found the above corrective actions to be satisf actory. However,
since the engineering evaluation had not been completed for the three workarounds,
additionalinspection will be performed to review the results of the evaluation. This
offort will be tracked as an inspection followup item (50 382/9724-03).
08.4 (Closedl EA 50 382/96-025/03014: Failure to properly test the Auxiliary
component cooling water system.
This violation was cited because the licensee f ailed to perform the system
surveillance test, as described in the applicable design documents. The licensee
tested the system with the discaarge valve closed instead of open, the normal
standby position for a design basis accident, bacause of a proceduralized
workaround.
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The corrective actions for this violation were the sam? as for
EA 50-382/96 025/01013, which is discussed in Section 08.3 of this report. Since
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the Inspectors found the corrective actions eatisfactory, this item is considered
closed.
08.5 1 Closed) LER 50 382/97-0Q5: Failure to perform Technical Specification required
reactor ecolant flow low operating bypass surveillance.
On February 20,1997, the licensee determinvd that a surveillance for the reactor
coolaat flow low bypass, required to be performed prior to reactor startup, had not
i been performed prior to entering Mode 2 in July 1989. The licensee verified that
the surveillance had been completed during all subsequent outages and identified the
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root cause as a falture to incorporate procedure cont ols following the modificat;on
That instal led the bypast circuitry in 1988.
The inspectors verified the following the correctit 3 actions were completed by the
licensee: (1) reviewed the event with operations and licensing department personnel
as part of their required reading; (2) impler inted repetitive tasks to test the bypass;
!3) revised Procedure CP 903-107, " Plant I otection System Channels ABCD
Functionel Test," Revision 13, to require performance of the bypass functional test
prior to each startup; and (4) initiated a modification for the bypass circuit that
would permit operation of all four reactor ciolant during the bypass test.
The failure to complete the surveillance of the bvoass prior to entering M 2 in
1989 is a violation of Technical Specification 4.3.1.2. This nonrepetitive,
licensee-identified, tnd corrected violation is being treated as a noncited violation
consistent with Section Vll.B.1 of the NRC Enforcemant Policy (50-382/9724-04).
08.6 LChsed) LER 50-392/97-025: Gag for Valve CC 835B was partially engaged, which
rastricted the valve to cpproximately 80 percent open.
On October 17,1997, the gag for Valve CC-835B was found partially engaged,
which restricted the CCW Haw to Containment Fan Coolers B and D. The root
cause was identified by the licensee as inadequate work Instructions.
The inspectors reviewed 'he corrective actions and found that appropriate guidance
had been implemented to ensure future work packages required the fuil stroke
- verification of air operated valves after the actuat9r gag had been disengaged
following maintenance. See Section O2.1 of this report for additional details.
- Based en review.of the corrective actions implementer by the licensee, this LER is
considered closed.
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11. Maintenance
- M1 ~ . Conduct of Maintenance
M1.1 - General Comments -
The inspectors observed the following surveillance activities:
- OP 303 068 -- Emergency Diesel Generator (EDG) and Subgroup Relay
Train A Operabili ty Test
- OP OO3 014. Control Room Heating and Venti;ation
in addition, the inspectors observed portions of the following maintenance activities
performed in accordance with the listed WA:
- WA 01164836 Replace pressure analog comparator card for Train A
shield building ventilation exhaust fan (S3V-114A) and
perform calibration. 1
- WA 01164976 Replace pump mounting bolts on EFW Pump A/B
- WA 01165761 Replace guide vane controller for Chill Water
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be good. All activities observed were performed with an appropriate author 5ation
package or test procedure. The inspectors observed supervisors monitoring job
progress.
M1.2. I&C Maintenance Activity
a. Insoection Scone (62707)
The inspectors observed portions of the maintenance activities to replace the
pressure analog comparator card for Train A shield building ventilation exhaust fan
(SRV 114A) and perform the instrument calibration.
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b. Observation ar d Fir;dirgi
' The inspectors attended the prejob briefing given by the l&C supervisor to the
te'chnicians for.WA 01164836. The ILC supervisor's projob briefing was clear,
detailed, and well presented,
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The inspectors observed the removal of the old pressure analog cw.parator card and
installation of the new pressure analog comparator card. The inspectors noted that
the technicians followed the work instructions, performed double verification, and
were very knowledgeable of the system. Upon completion of the maintenance
activity, the l&C technicians performed the calibration using Procedure Mi-005 251,
" Westinghouse 7300 In Place Card Calibration," Revision 6. Instrumentation used
for the calibration of the new pressure analog comparator card was verified by the
inspectors to be within the required calibration dates,
c. Conclusions
Replacement of the pressure analog comparator card was performes :n a
professional manner, in accordance with work instructions, and received good
.apervisory oversight.
M2 Maintenance and Material Condition of Facilities and Equipment
M 2.1 EDS B Postmaintenance Ooerability Verification
a. Insocction Scone (62707)
The inspectors reviewed the adequacy of corrective actions initiated by the licensee
in response to a f ailed postmaintenance operability verification on EDG B.
b. Observations and Findings
CR 97 2624 was initiated because EDG B had tripped during the pedumance of
Procedure OP 903-068, " Emergency Diesel Generator and Subgroup Helay .
Operability Verification," Revision 12, following maintenance. The licensee stated
that the trip occurred approximately 16 20 seconds after reaching rated speed and
) voltage during a manual start initiated by the operators,
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The oper its performed several instrumented test runs on EDG B but could not
duplicat he original failure. All manual starts were successful. Additionally, a
number of components that could have cont: buted to or caused tt e original f ailure
were tested and no deficiencies were identified. The licensee was cble to show that
the part of the starting circuit that was the most probable cause of .ne failure was
no, in the emergency start circuit and would have been bypassed during an
emergency start.
c. Conclusions
The cause of the f ailure wcs not determined; however, the safety significance was
considered negligible as the suspected cause of the failure would not have
prevented an Emeigency start.
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M2.2 Maintenance Sula
a. Insoection Scone (62706)
The inspectors reviewed the maintenance history and current maintenance activities
for the process radiation monitors to determine if the system was appropriately
monitored under the licensee's maintenance rule program and whether goals
established were commensurate with safety.
b. Observations and Findinas
The process radiation monitoring system consists of a total of nine process radiation
monitors that were included in the Maintenance Rule Program. The system was
initially placed in the a(2) category when the Maintenance Rula Program was
implemented in July 1998. The performance criteria established for this system was
less than or equal to two MPFF per 3 years. However, the system wss placed in the
all) category, in January 1997, because it did not meet its performance criteria due
to exceeding two MPFF in 3 years. The licensee had established goals to monitor
the process radiation monitor system. The inspectors determined through review of
maintenance history that the licensee's determination of MPFFs was appropriate and
that the licensee's goals for monitoring the system were satisf actory.
The process radiation monitor system was being implemented in accordance with
10 CFR 50.65, the licensee's maintenance rule program, and commensurate with
safety.
c. Conclusions
The licensee had appropriately determined MPFF for the process radiation monitor
system, and the system was being implemented in accordance with 10 CFR 50.65,
the licensee's maintenance rule program, and commensurate with safety.
M8 Miscellar.eous Maintenance issues (92902)
M P.1 (Closed) Violation 50-382/9701-01: Failure to include a safety-related system
! containment atmosphere relief system) into the maintencnce rule program scope.
The inspectors verified the corrective actions described in the violation response
were reasonable and appropriately implemented. No similar problems were
identified.
. M8.2 : IClosed) Violation 50-382/9701-02: Failure to monitor the unavailability of
functions associated with the engineered safety feature a.:tuatica system, plant
protection system, core protection calculators, broad range gas monitors, and
- containtnent polar crane.
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The inspectors verified the corrective actions described in the violation response to
be reasonable , 'd appropriately implemented. No similar problems were identified.
M8.3 (Closed) EA 50 382!97-025/02014: Change in the scope of a WA without the
originators review.
~ This violat=n was identified because a system engineer marked the differential
pressure test for Valves CS 125A(B) "nat applicable" without the original reviewers
reviewing the change. Similarly, a maintenance planner marked a postmaintenance
test as "not applicable" without the consent of the original reviewers.
The inspectors verified that the licensee had issued a memorandum reemphasizing
the procedure requirement for review of work package scope changes, Further, the
inspectors verified that the licensee clarified the requirements in
Procedure UNT 005-015, " Work Authorization Preparation and Unplementation," for
what constitutes a change !n work scype. The inspectors found these corrective
actions satisfactory,
111. Enaineerina
E1 Conduct of Engineering
E1.1 Evaluation of Vortex Calculation Deficiencv
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a. Scoce (92903. 37551)
The inspectors reviewed the circumstances related to the calculation generated to
determine the onset of vortexing in various safety-related tanks. The inspectors
discussed the detailed engineering evaluation with the design engineer who prepared
the evaluation and reviewed several documents referenced in the operability
evaluation for CR 97-1596.
b. Observations and Findinas
in August 1995, a licensee seif assessment of the EFW system identified that the
CSP design basis did not include an allowance for vortexing; consequently, the
licensee initiated CR 95-0657 to document this design deficiency and developed a
calculation to document tt = onset of vortexing in various safety-related tanks.
Calculation EC M95-012,_" Minimum Pipe Submergence to Prevent Vortexing,"
Revision 0, determined the minimum level for vortexing in the CSP based on vortex
height versus flow curve in a vendor pump manual,
in May 1996, the licensee contracted with Combustion Engineering to perform a
calculation to determine the onset of vortexing in the refueling water storage pool in
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order to take advantage of the expertise in this area by an individual who worked at
Combustion Engineering. In December 1996, the licensee revised
Calculation EC-M95 012 to determine the level for vortexing in the safety-related
tanks using the method developed by Combustion Engineering. The licensee made
this decision to take advantage of the analytical methodology rather than relying on
a curve from a vendor manual.
On July 17,1996, the licensee submitted Technical Specification Change Request
NPF 38170 to raise the CSP level from 82 to 91 percent to account for vortexing
and instrumerit uncertainty. On June 3,1997, the licensee supplemented Technical
Specification change request NPF 38-179 witt. additionalinformation that accounted
for a previous failure to consider the increase in short term volume required for the
CCW makeup system in the design basis of the CSP. The supplement attached
Calculation EC-M95-012, Revision 1, and addressed instrument uncertainties related
to operation of the controlled ventilation area system on the CSP.
During review of the July 1997 supplement to Technical Specification change
request NPF 38-179, an NRC reviewer questioned the conservatism of the value for
the onset of vortexing in tiie CSP (1.53 percent level). The reviewer held
discussions with the licensee on June 10 and 17,19P7, to urderstand the basis of
the analytical method documented in Calculation EC-M95-012, Revision 1.
Additionally, the NRC reviewer indicated a concern as a result of his knowledge of
the sump tests documented in NUREG CR-2759, "A Parametric Study of
Containment Emergency E, ump Performance Results of Vertical Outlet Sump Tests."
The licensee did not agree that the value determined by their analytical method was
noncenservative, but acknowledged that empirical test data was needed to support
the methodology.
To demonstrate that the analytical model supported the determination of the onset
of the point of vortexing 'n the CSP, the licensee developed a scale model of the
pool. The tests performed in the scale model demonstrated that the analytical
method was nonconservative related to the onset of vortexing. The licensee
initiated CR C7-1596 tc, document that Calculation EC-M95-012, Revision 1, was
nonconservative since the methodology employed was based on static tank
conditions and did not account for recirculation flow to the refueling water storage
and condensate stomoe pools. Immediate corrective actions for this deficiency
involved the modeling ;f vortex breakers in the CSP scale mode! and installing the
actual vortex breakers in the pool. Since engineers hac; used the same calculation
method on all of their safety related tanks, which included the refueling water
storage pool, the licensee assessed the other safety-related tanks.
The licensee febricated a scale model of the refueling water storage pool, without
vortex breakers installed, to determine the actual level for the onset of vortexing to
provide inforniation for a past operability determination. In addition, the licenseo
modeled cruciform vortex breakers to demonstrate that the planned corrective
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actions would correct the deficiency. The model and evaluations demonstrated that
vortexing would not occur with the vortex breakers installed. However, additional
evaluation was necessary to demonstrate that the low pressure safety injection,
high pressure safety injection, and containment spray pumps remained operable prior
to transfer from the refueling water storage pool to the containment sump.
The design engineer used available industry information on swirling flow and
vortexing in containmo71 sumps and us'd the video tape of the oaset of vortoxing in
the scale model of the refueling water storage pool to perform a detailed engineering
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evaluation. The engineer determined that the minimum refueling water storage pool
level that would have been required to prevent vortexing was 25.6 inches, which
corresponded to the beginning of a swirling Type 6 (full air core) vortex. However,
'hc minimum refueling water stora3e poollevel achieved when a recirculation
actuation signal occurred corresponded to 13.1 inches. The engineer concluded that
vortexing would have occurred 12.5 inches abave the recirculation actuation signal
setpoint, which corresponded to about 30,000 gallons of refueling water storage
poolinventory. At a rate of 8400 gpm (required combined accident flow rate for the
low pressure safety injection, high pressure safety injection, and containment spray
pumps) from the refueling water storage pool, the pumps would operate for
approximately 4 minutes with vortexing occurring.
The inspectors, in consultation with an NRC reiewer, confirmed that the
methodology employed in Calculation EC-MC7-026, " Required Submergence to
Prevent Vortexing in the RWSP," satisf actorily demonstrated the physical
characteristics to be expected in a design basis accident. The inspectors noted that
this followed the same methodology used in determining the onset of vortexing in
the CSP, which the NRC reviewer had evaluated. The inspectors agreed with the
design engineer's determination that a fuil air core vortex would be generated and
that vortexing would be limited to air ingestion of 2 percent by volume. The design
enginee ased the industry experience described in NUREG CR-2759; the
conclusions in the report " Swirling Flow Problems at intakes," dated 1987; the test
data from *he sca'e model; and the video generated during scale model testing to
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determine that the safety injection and spray pumps remained operable.
The inspectors reviewed the past operr.ility evaluation, interviewed the engineer
who performed the operability evaluation, and assessed the soundness of ti.e
engineering judgment used to conclude that safety systems remained operable. The
inspectors agreed with the conclusion that the low pressure safety injection, high
pressure safety injection, and containment spray pumps would have remained
operable prior to transfer from the refueling water storage pool to the contain. ment
sump. The inspectors noted that the licensee required a detailed evaluation to
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justify past operability and that an NRC reviewer questioned conservatism in the
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licensee's calculation. The f aLure to ensure that design basis information was
properly transferred into a calculation (specification) is considered a violaticn of
Criterion ill (50 382/9724-05).
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c. Conclusions
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After an NRC reviewer questioned conservatism in the calculation for determining
the onset of vortexing in the CS:', the licensee determined that their methodology
was nonconsarvative. The failure to account for recirculation to the tanks, resulting
in a nonconservative determination for the onset of vortexing, is a violation.
E2 Engineering Support of Facilities and Equipment -
E2.1 Enoineerino Evaluation of CSP Loss of Inventerv Due to a Sinole Failure
a. insoection Scoce (37551171707)
The inspectors verified that immediate contingency actions were reason 9ble and had
been implemented and reviewed the engineering evaluation,
b. Observations and Findines
On November 5,1997, during a system review, an engineer discovered that the
CCW makeup system was subject to a single failure that could remdly reduce
inventory in the CSP, thus reducing water available to the EFW system during
accident conditions. Upon discovery, CR 97-2551 was generated to document this
issue.
Several contingency actions were implemented that required operators to take
mamal actions to mitigate the consequences if a single failure occurred. The
contingencies identified the alarms and indications that opuators coula expect to
see and the subsequent actions required to be performed by the operators. The
inspectors verified that the contingency actions were incorporated in the control
room procedures and that the operators understood the requirements.
The engineers completed an operability assessment in a timely manner. The
%ssessment was detailed and addressed all systems that could potentially be
affected by single failure of any one of the CCW makeup isolation valves failing in
the open position during a loss of offsite power. The system tank level switches
were also evaluated for single failure, which coue result in a continuous demand for
CCW makeup. The engineers found that continuous makeup to any of the tanks
would result in flooding areas in the RAB, potentially containing safety-related
equipment.
The engineering ev'aluation concluded that the essential chill water, CCW, Auxiliary
component cooling water, EDG and EFW systems remained capable of performing
their safety function. The inspector agreed with the conclusion in the engineering
evaluation for the ability of the systems to perform their intended safety function.
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LER 97 026, " Single Failure Effects Condensate Storage Pool Inventory," was issued
to address this deficiency. A root cause analysis was in progress and the licensee
,vas in the process of determining whether or not a modification would be required
for the final corrective actions. The LER will be amended when the root cause
analysis has been completed. Routine foilowup review will be per*ormed when the
LER is received,
c. Conclusions
The inspectors reviewed the engineering evaluation and determined that it was
thorough, timely, and addressed the issues appropriately.
E8 Miscellaneous Engineering issues (92903)
E8.1 (Closed) Insoection Followuo item 50-382/9607-03: Toxic gas detectors not
provided for the south air intake.
This item was initiated to ensure review of the requirements for in-line chlorine and
toxic gas monitors for both the north and south air intakes. The inspectors verified
that, the current configuration raquirement to ha,a toxic gas and chlorir.e detectors
at the north but ntt the south air intake complies with the current licensing basis.
E8.?. (Closed) hsoection Followao item 50 382/9607 04: Leak testing of emergency
intake dampers.
This item was initiated to ensure review of the requirements to perform leak testing
of the emergency intake dampers installed in series in both the north and south fresh
a; intakes. Thr. hspectors determined that the decision to not test the emergency
air intake dampars because they are considered low leakage and because testing
- onfirmed they were low leakage complies with their current licensing basis.
E8.3 (Closed) Violation 50-382/9607-05: Failure to implement effective corrective
actions to preclude repetition of the breach of the control room boundary.
This violation resulted from a failure of engineering and operations personnel to have
a self-critical and questioning attitude. Personnel f ailed to question the capability of
a single control room airlock door to maintain control room integrity under
design-basis requirements.
The inspectors verified that the licensee initiated actions to address organizational
performance and facility culture issues and implemented changes to their corrective
action process to increase the sensitivity to deficient conditions. The inspectors
noted that the number of CR identifying deficietit conditions had increased
noticeably. Further, the inspectors noted that an increasing number of design basis
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waaknesses were being identified by plant personnel. The inspectors found these
corrective actions satisf actory.
E8.4 [Closedl Violujon 50 382/9704-06:- Inadequate safety evaluation for containment
isolation valvas.
This violation resulted because a 10 CFR 50.59 evaluation had allowed the licensee _ /*
to credit Valve EFW 224A, EFW flow control, as a containment isolation valve when
it did not meet all the requirements for such credit. From June 11-14,1996,-
operators relied upon Valve EFW-224A as a containment isolation valvo for
62.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />; however, the position indicator for Valve EFW 224A did not meet the
requirements of Regulatory Guide 1.97, " Instrumentation for Light Water Cooled
- Nuclear Power Plants to Assess Plant and Environs Conditions During and Following
an Accident," in that it did not have " direct" position indication.
The inspectors verified the licensee implemented the following corrective actions:
(1) established appropriata guidance in Procedure OP-100-014, " Technical
Specifications and Technical Requirements Compliance," Section 5.2.18.6 to
-prohibit use of the flow control valves as containment isolation valves; (2' prepared
update paget to Updated Final Safety Analysis Report and updated the Technical
Requirements Manual; and (3) provided training to licensing and design engineering
personnel on the event and 10 CFR 50.59 requirements. The inspectors found
these corrective actions satisfactory.
E8.5 [ Closed) LER 50-382/97-001: Regulatory Guide 1.97 containment isolation valve
position indication.
The corrective actions for this event report were the same as
Violation 50-382/9704-06, which was closed in Section E8.4 of this inspection
. report. This item is considered closed.
IV. Plant Suncort
P1 Conduct of Emergency Planning Activities (71750)
P1.1 Biennial Exercise
On November 5,1997, the inspectors participated in the graded biennial exercise. -
The inspectors observed activities in the control room simulator and relocated to the
technical support center when the shift superintendent transferred emergency.
director responsibilities to that facility director. The inspectors observed good
command and contro!in both facilities. Communications within the areas tended to
be complete, three-way communications. However, there were instances when
external communications appeared to be incomplete or misleading. All issues were
- addressed in NRC Inspection Report 50-382/97-18,
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V. Management Meetings
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X1 . Exit Meeting Summary
. The inspectors presented the inspection results to members of licensee management
on December 18,1997. The licensee acknowledged the findings presented.
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Proprietary information reviewed by the inspectors was returned to the appropriate
individuals.
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ATTACHMENI
SUPPLEMENTAL INFORM ATION
PARTIAL LIST OF PERSONS CONTACTED
Licensee
E. G. Beckendorf, Superintendent, Security
S. G. Bruner, Manager, Planning and Scheduling '
F. J. Drummond, Director Site Support -
C. M. Dugger, Vice-President, Operations
T. J. Gaudet, Manager, Licens:ng
E. C. Ewing, Director, Nuclear Safety & Regulatory Affairs
C. Fugate, Superinter dent, Operations
P. A, Gropp, Manager, Design Engineering-
J. G. Hoffpauir, Manager, Operations
T. R. Leonard, General Manager, Plant Operations
T. P. Lett, Lead Supervisor, Rad!ation Protection
J. J. Lewis, Manager, Emergency Planning
D. C. Matheny, Outage Manager
- D. Matthews, Specialist, tJcensing
- G. D. Pierce, Director of Quality
D. L. Shipman, Maintenance
D. W. Vinci, Superintendent, System Engineering
A. J. Wrape, Director, Design Engineering
INSPECTION PROCEDURES USED
IP 3,551: Onsite Engineering
IP 62706: Maintenance Rule
IP 62707: Malntenance Observations
IP 61726: Surveillance Observations
IP 71707: Plant Operations
- IP 71750: Plant Support Activities
_
_IP 92901: _ Followup - Operations
IP 92902: Followup - Maintenance
-- IP 92903: - Followup - Engineering
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i ITEMG OPENED, CLOSED, AND DISCUSSF.D
Ooened
50-382/9724-01 VIO Inadequate instructions provided in a WA
for Valve CC-835B (Section 02.1).
50-382/9724-02 URI Dirt and debris in RAB floor drains (Section 02.2).
50 382/9724-03 IFl Review workaround evaluations (Section 08.3)
50-382/9724-04 NCV Failure to comolete the surveillance for flow low bypass
(Section 08.5).
50-382/9724-05 VIO Vortexing calculation not adequate (Section E1.1)
Clated
50 382/96-004 LER Failure to meet intent of Technical Specification
surveillance because of inadequate corrective actions
(Section 08.1).
50-382/96-006 LER Reactor trip following a failure of the CED M/G set
voltage regulator (Section 08.2).
50-382/96-025/01013 EA Failure to preclude voids in the Auxiliary component
cooling water system (Section 08.3).
50-382/96-025/030 4 EA Failure to properly test the Auxiliary component cooling
water system (Section 08.4).
50-382/97-005 LER Failure to perform flow low bypass surveillance
(Section 08.5).
50-382/9724-04 NCV Failure to complete the surveillance for flow low bypasu
(Section 08.5).
50-382/97-025 LER Gag for Valve CC-835B was partially engaged
iSection 08.6).
50-382/9701-01 VIO Failure to include the containment atmosphere relief
systern into the maintenance rule program
(Section M8.1).
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50 382/9701-02 VIO Fail'are to monitor the unavailability of various plant j
- systems (Section M8.2).
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50 382/97-025/02014 EA Change in the scope of a WA without the originators I
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review (Section M8.3).
50-382/9607-03 IFl Toxic gas detectors not provided for the south air intake
(Section E8.1).
50 382/9607-04 :IFl Leak testing of ' emergency intake dampers
(Section E8.2).
50-382/9607-05 VIO Failure to implement effective corrective actions to
preclude repetition of the breach of the control room
boundary (Section E8.3).
60 382/9704-06 VIO Inadequate safety evaluation for containment isolation
valves (Section E8.4).
50-382/97-001- LER Regulatory Guide 1.97 containment isolation valve
position indication (Section E8.5).
LIST OF ACRONYMS USED
~ CCW compone:.i cooling water
CFR Code of Federal Regulations
CR conditbn report
CSP condensate storage pool
EA enforcement action
EDG- emergency' diesel generator
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fgprn gallons per minute ,
IFl - inspection followup item
'LER licensee event report
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- M/G . : motor / generator -
-MPFF maintenance preventable functional failure
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NCV noncited violation-
NRC Nuclear Regulatory Commission
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PDR public document room -
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- RAB: - reactor auxiliary building -
VIO violation
URI unresolved item
.WA work authorization '
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