ML20199H024
| ML20199H024 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 11/21/1997 |
| From: | Tapia J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| Shared Package | |
| ML20199H018 | List: |
| References | |
| 50-445-97-18, 50-446-97-18, NUDOCS 9711250361 | |
| Download: ML20199H024 (22) | |
See also: IR 05000445/1997018
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ENCLOSURL2
U.S. NUCLEAR REGULATORY COMMISSION
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REGION IV
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Docket Nos.:
50 440
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50 446
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License Nos.:
NPF 87
NPF 89
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Report No.:
50-445/97 18
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50-446/97 18
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Licensee:
TU Electric
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Facility:
Comanche Peak Steam Electric Station, Units 1 and 2
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Location:
Fti 56
Glen Rose, Texas
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Dates:
August 31 through October 11,1997
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Inspector:
H. A. Freeman, Acting Senior Resident inspector
Approved By:
J. l. Tapia, Chief, Projects 8 ranch A
Division of Reactor Projects
Attachment:
Supplemental Information
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EXECUTIVE SUMMARY
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Comanche Peak Steam Electric Station, Units 1 and 2
NRC Inspection Report 50 445/97 18;50-446/97 18
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Operations
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The licensee con:inued to pay close attention to the material condition of the plant.
This was especially significant consideririg the increasing level of activity in
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preparation for the Unit 2 refueling outage. The licensee took prompt corrective.
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actions on two issues outside the control room, which could have led to a reactor
trip had the condition been left uncorrected (Section 01.2).
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Overall, conduct of operations continued to be very good. The plant operated in a
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safety conscious manner with appropriate supervisory and management oversight.
With the exception of the boron thermal reneration system leakage, good
performance by operators was noted for severalissues (Section 01.2).
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A vague procedure, combined with an operating crew that did not fully review-
. equipment status, lead to the contamination of several areas while flushing
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the boron thermal reneration system. The event indicated a weakness in attention-
to detail and an overreliance on the procedure (Section 01.3).
The licensee identified and took prompt, conservative actions on two issues where
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the design assumptions had not been fully implemented. These issues indicated
that the licensee continued to perform thorough reviews of plant systems and
procedures as expected by their response to 10 CFR 50.54(f) (Sections 03.1
and M1.2).
Maintenance
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While the standardization of sensors conducted prior to the surveillance testing of
the hydrogen recombiner did not constitute preconditioning, the activity was not
included in the procedures and was a violation of 10 CFR Part 50, Appendix B,
Criterion V, for procedure adequacy. This lack of procedural direction lead to
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inconsistent performance (Section M3.1).
Enaineerina
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The licensee identified that two throttle valves in each unit may have minimum gap
openings which are smaller than the mesh on the emergency core cooling
system (ECCS) sumps. The licensee had previously evaluated the industry
information 'concerning the throttle valves, but the original evaluation did not
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consider the disk guide rings and f ailed to recognize that the minimum gap between
the guide rings and the valve body could be smaller than the disk to seat gap
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(Section E1.1).
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Surveillance procedures for the control room filtration / pressurization system failed to
implement adequate acceptance limits; and as a consequence, the as left value for
pressurization unit flow exceeded design basis limits on two occasions. This was a
violation of 10 CFR Part 50, Appendix 0, Criterion V, in th6t the licensee did not
appropriately implement design limits into the survealance tests (Section E3.1).
During a surveillance test of the control ro,m pressurization unit, engineers
performing the test failed to use a temperature measuring instrument which met
procedural accuracy requirements. This was a violation of Technical Specification 6.8.1 and was caused by a lack of attention to-detail (Section E4.1).
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Report Details
Sumtriarv of Plant Statug
Units 1 and 2 operated at essentially 100 percent power throughout the inspection period.-
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1. Operations
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Conduct of Operations
01.1 Plant Tours
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a.-
Inspection Scooe (71707)
The inspectors conducted frequent plant tours to verify safe operation of plant
equipment and to inspect general plant material and housekeeping conditions. As
part of the tours, the inspectors performed routine control room observations and
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walkdowns of safety related flow paths and locked component lists.
b.
Observations and Findinos
Overall, the inspectors determined that operations personnel operated the plant in a
safety conscious manner with appropriate management oversight. Safety systems
were properly aligned. Plant housekeeping and material condition of plant
equipment were excellent. The inspectors identified several minor housekeeping
and equipment material deficiencies. These deficiencies were appropriately
dispositioned by the licensee.
01.2 Plant Material Condition
a.
laspection Scope (71707)
The inspector reviewed control room logs, problem identification forms, toured the
plant, and attended daily planning meetings to evaluate the licensee's ability to
identify and correct material condition problems.
b.
Observations and Findinas
The inspector found that the licensee was doing a very good job of identifying and
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correcting plant material condition problems. This was evident even with the
increased level of activity due to outage preparations. Two items warranted special
recognition because either item could have led to a reactor trip if left uncorrected.
- The first example involved the identification by a plant equipment operator that a
scaffold platform erected around a Unit 2 feedwater flow control valve would have
impeded the valve movement during a downpower. The operator recognized that,
due to the unusual nature of the valve, the valve body moves outward during
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closing. This identification was timely because a downpower was scheduled for the
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following evening. The scaffold was immediately removed.
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The second example involved the identification and reporting by an individual
responsible for the cleanliness in an area in the Unit 1 turbine building that a sink
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drain was clogged and overflowing. The prompt team investigated and found that a
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sampling line from primary head tank was not fully closed. The sample line was
closed and the tank refilled. Had the tank continued to drain, a generator
trip / reactor trip could have occurred due to low level.
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c.
Conclusions
The licensee continued to pay close attention to the material condition of the plant.
- This was especially significant considering the increasing level of activity in
preparations for the Unit 2 refueling outage. The licensee identified two issues
-which could have led to reactor trips had the conditions been left uncorrected. The
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licensee took prompt corrective actions.
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01.3 Boron Thermal Reaeneration System Lenkaoe
a.
Inspection Scope (71707)
The inspector reviewed the cause and circumstances surrounding the contamination
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of several areas in the auxiliary building,
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b.
Observations and Findinas
On October 2, while performing a flush of the boron thermal regeneration system in
preparation for the upcoming Unit 2 refueling outage, the licensee failed to open a
discharge valve and ended up pressurizing several diaphram operated valves and
contaminating several areas. The inspector reviewed Standard Operating
Procedure SOP 106B, " Boron Thermal Regeneration System," and found the
procedure vague in that it led operators to believe that they did not have to conduct
Section 5.1 prior to conducting a flush if the system was isolated for less than 14
days. The inspector found that the operating crew did not meet management's
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expectation in regards to verifying proper initial conditions prior to performing the
activity,
c.
Conclusions
This event is an isolated example of a knowledge deficiency of system operation by
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operators.
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03
Operations Procedures and Documentation
03.1 Catalvtic Hydroaen Recombiner Procedure Chanae
a.
Insucction Scope (627071
The inspector reviewed the identification and significance of operating the waste
gas processing system catalytic hydrogen recombiner with the product hydrogen
above the alarm setpoint.
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b.
Observations and Findinas
On October 10,1997, the licensee informed the inspector that, during the review of
a question concerning potential preconditioning of the catalytic hydrogen
recombiner, the system engineer had identified that the recombiner was routinely
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operated above the product hydrogen high alarm setpoint and that the operating
procedure had recently been modified to allow operation with up to 2 percent
product hydrogen concentration. The alarm setpoint was set at 0.25 percent. The
licenseo initiated a operations notification evaluation (ONE) form documenting the
fact that the procedure had been changed without performing a safety evaluation
and danger-tagged the system until the issues could be resolved. The licensee had
originally performed a 10 CFR 50.59 screening and had erroneously determined that
the procedure change did not cortatitute a change to the facility description.
The Final Safety Analysis Report, Section 11.3.2.1.2, states, "if hydrogen in the
recombiner discharge exceeds 0.25 percent by volume, an alarm sounds. This
alarm warns of high hydrogen feed, possible reactor malfunction, or loss of oxygen
feed." Design Basis Document ME 269, " Gaseous Waste Processing System,"
stated that the hydrogen recombiner gas analyzer high process limit was
0.25 percent based on vendor manuals. Operating with the product hydrogen
above 0.25 percent had no safety significance. The operating limits.and alarm
setpoint had originally been selected based on different detectors which could
differentiate between hydrogen and helium. Operating the catalytic recombiner with
product hydrogen above 0.25 percent ensures that the system is operating in an
oxygen deficient mode. This also ensures that a dangerous buildup of oxygen and
hydrogen cannot occur in the hold up tanks. At the end of the inspection period,
the licensee was completing a safety evaluation to change the operating procedure
and raise the setpoint.
The inspector determined that the changes to the catalytic hydrogen recombiner
operating procedure constituted a change to the facility, as described in the Final
Safety Analysis Report, and that a written safety evaluation documenting that the
change did not constitute an unreviewed safety question was not performed,
contrary to 10 CFR 50.59. This nonrepetitive, licensee-identified violation is being
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treated as a noncited violation (NCV), consistent with Section Vll.B.1 of the "NRC
Enforcement Policy" (50-445/9718-01; 50-446/9718-01) (EA 97 550).
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The it.spector concluded that the violation occurred as a result of poor
communications between radwaste operations and system engineering. The
inspector found the licensee's actions to resolve the issue were appropriate.
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Operator Training and Qualification
a.
Insr,ection Scone (71707)
The inspector attended the classroom portion of licensed operator training on
reduced inventory. The licensee was conducting the training in preparation for the
Unit 2 refueling outage,
b.
Observations and Findinas
Training on midloop operations was thorough, well presented, and actively involved
the etitire crew. Topics included recent industry events and discussions on how to
avoid similar problems. The inspector concluded that the training was effective in
refreshing the operators's understanding of procedures and potential problems
involved in reduced inventory operations. The timing of *he training was
appropriate.
08
Miscellaneous Operations lasues
08.1 (Closed) Licensee Event Report (LER) 50-445/95007: Engineered safety
feature actuation caused by feedwater recirculatiori valve failing open due to a
failure in the power supply card. This event was discussed in NRC Inspection
Report 50-445/95 28;50 446/95 28. No new issues were revealed by the LER
08.2 (Closed) Violation 50-446/9715-01: Operation in excess of 102 percent thermal
power. In the enclosed Notice to NRC Inspection Report 50 445/97-15;
50-446/97 15, the NRC concluded that the information regarding the reason for the
violation and the corrective actions taken and planned were already adequately
addressed on the docket and that a response was not necessary unless the licensee
concluded that the descriptions or corrective actions did not accurately reflect their
position. The licensee did not respond and this item is closed.
II. Maintenance
M1
Conduct of Maintenance
M 1.1 Control Rqom Emeroenc. Pressurization Unit Carbon Sampie Surveillance Failure
a.
insmection Scone (62707)
On September 16,1997, the licensee identified that recently drawn carbon samples
from both trains of the cont.. I toom emergency pressurization system failed a
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surveillance test for methyliodide penetration. The inspector reviewed the
Technical Specification and basis for the surveillance test, the design basis
document fc the control room emergency filtration / pressurization system, operating
procedures, and design drawings. The inspecor also consulted with NRC personnel
concerning the licensee's interpretation of the surveillance requirements.
b.
Observations and Findinos
On September 16, a contractor laboratory informed the licensee that the samples
from the pressurization units drawn on August 22 and 25 had failed the methyl
iodide test with penetration results of 0.769 and 0.875 percent. The samples from
the filtration units had passed with penetration results of 0.011 and 0.023 percent.
Technical Specification Surveillance Requirement 4.7.7.1b(2) requires that each
control room emergency filtration / pressurization system train be demonstrated
oposable at least once per 18 months, by testing a representative carbon sample to
ensure that the methyl iodide penetration was less than 0.2 percent. The limiting
condition for operation allows one train to be inoperable for up to 7 days and has no
provision for having both trains inoperable. By design, each pressurization unit
operates in conjunction with its respective filtration unit. The licensee concluded
that, while the pressurization units were inoperable for methyl iodide penetration,
thq filtration / pressurization system train was operable; and, thereforc, entry into
Technical Specific 3 tion 3.0.3 was not requireo.
Each emergency pressurization unit draws a maximum of 800 cfm of outside air
through a carbon filter bed and ditcharges into the intake of its respective filtration
unit, in the filtration unit, the air is mixed with approximately 7200 cfm of air being
recirculated from the control room environment and passed through a second
carbon filter bed. The inspector reviewed the design basis and found that the
calculation did not account for the removal efficiency of the pressurization unit filter
(99 percent) in estimating the dose to control room operators during design basis
accidents. Therefore, from a design basis standpoint, the reduced efficiency of the
pressurization units had no effect on system operation.
Through a review of the Technical Specifications and bases, tha Ni;C staff agreed
with the licensee's conclusion that the Technical Specifications did not requi'e that
each pressurization unit meet the methyl iodido penetration surveillance requirement
separate from its respective filtration unit.
The licensee replaced and tested the carbon in one unit on September 17 and
replaced and tested the carbon in the other unit the following day. Licensee
engineers along with operations and maintenance personnel met to discuss
problems concerning the pressurization unit surveillance. The licensee identified
that performing the survei' lance on both trains during the same time frame reduces
the opportunities to identifying potential common failure mode problems. The
licensee intended to have the f ailed carbon analyzed to try to determine whether the
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problem was a common mode failure. Additionally, the licensee was reviewing
other surveillance procedures to identify similar implementation problems.
c.
Conclusions
The licensee correctly implemented the surveillance requirement for the control
room emergency filtration / pressurization system.
M1.2 Dutaae Prenoration
a.
Insocction Scope 162707)
During routine tours of the f acility, the inspector noted that the licensee had
connected an integrated leak rate test rig to the exterior of the Unit 2 safeguards
building. The inspector questioned the licensee regarding the seismic qualifications
of the test connection and test rig,
b.
Observations and Findinas
The inspector questioned the licensee as to whether the connection between the
seismically qualified Unit 2 safeguards building and the temporary equipment for the
integrated leak rate test had been appropriately analyzed. The licensee could not
identify a seismic evaluation for the connection, therefore, a ONE form to
investigate the issue was written. The licensee also disconnected the skid from the
test connection. The licensee informed the inspector that they had never connected
the equipment to the test connection prior to shutting down the unit during past
outages. This item will remain open pending review of the licencee's determination
of the seismic qualifications of the connection (50-445/97184 : 50 446/9718-02).
M3
Maintenance Procedures and Documentation
M 3.1 E,xplosive Gas Monitorina Instrumentation
a.
Inspection Scone (61726)
On September 30, the inspector witnessed a surveillance test performed on the feed
gas hydrogen and oxygen analyzers for Catalytic Recombiner X-01 of the waste gas
holdup system, The inspector reviewed the surveillance test and related tests for
conformance to Technical Specifierion surveillance requirements. The inspector
reviewed whether nonproceduralized actions performed by the technicians could
precondition the recombiner and cause the detectors to pass the surveillance test.
b.
Observations and Findinns
The technicians performed the analog channel operational test (ACOT) in
accordance with Procedure INC-7841X, "ACOT/CHAN CAL Catalytic
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Recombiner X 01 Feed Gas Hydrogen and Oxygen Analyzer, CM ^ 127A,"
Revision 4. The purpose of the procedure was "to verify and, if required,
re establieh the accuracies and contro! functions of the channel sensors and
associated signal processing equipment . . . ."
During the surveillance test, an alarm at the waste gas panel could not be reset.
The technicians reperformed that section of the surveillance test and reset the
alarm. The technicians halted the test and informed the shif t manager and their
supervisor. The licensee concluded that the failure of the alarm to reset did not
affect the operability of the equipment and completed the test. The technicians
submitted a work request to troubleshoot the alarm reset function. The inspector
verified that reperforming portions of the procedurr was an accepted practice. The
inspector found that the licensee appropriately considered the impact of the alarm
reset f ailure on operability.
The inspector noted that, although the activity was not part of the procedure, the
technicians had standardized the detectors prior to the surveillance test. A
radwaste operator ir. formed the inspector that, prior to placing a recombiner in
service, the do! ,ctors usually required standardization. On October 8, the inspector
met with the licenseo to discuss potential preconditioning of the recombiners prior
to performing the surveillance tests. The licensee informed the inspector that they
were submitting a ONE form concerning potential preconditioning.
Standardization allows the detector to determine the permeability of the sensors.
The Technical Specifications define an ACOT to be, "the injection of a simulated
signal into the channel as close to the sensor as practicable to verify operability of
alarm, interlock an/or trip functions.1he ACOT shallinclude adjustments, as
necessary, of the alarm, interlock and/or trip setpoints such that the setpoints are
within the required range and accuracy." The inspector concluded that
standardizing the detectors did not affect any alarm, interlock or trip functions of
the detector and did not constitute preconditioning of the ACOT.
The licensee stated that standardization is usually performed after placing the unit in
service. While out of service, the recombiner is left with a dry purge gas flowing
through the sensors. The sensor membrane dries out by the purge which affects its
readings. When placed back in service, the sensors are in a high humidity
environment and the readings between the feed and product sensors may differ, if
the readings differ by more than 1 percent, the licensee performs a standardization.
This requirement was not proceduralized,
c.
Conclusions
Since standardization prior to conducting Technical Specification surveillance tests
was not consistently performed, the ability to verify channel accuracy may have
t.een affected. The inspector concluded that Procedures INC-7841X and
INC-7845X f ailed to include instructions for performing standardization of the
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violation of 10 CFR Part 50, Appendix B, Criterion V, 150-445/9718 03;
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50 446/9718 03h
M3.2- Containment Isolatlon Surveillance Test
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a.
Inspection Scope (617261
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On October 9, the licensee conducted a slave relay actuation surveillance test using
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Procedure OPT 484B, " Train B Safeguards Slave Relay K630 Actuation Test." The
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- shift supervisor informed the inspector that this surveillance test would shut
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steam generator sample isolation valves and feedwater loop sample isolation valves,
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but that letdown containment isolation Valve 2 8152 would not shut because of
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a jumper installed as part of the procedure. The inspector reviewed
Procedure OPT 461B, " Train A Safeguards Slave Relay K630 Actuation Test," and
noted that it did not test letdown containment isolation Valve 2 8160.
The inspector reviewed other surveillance test procedures to verify that the letdown
containment isolation valves were, in fact, tested in accordance with Technical
Specification 4,6.3.
b.
Observations and Findinas
Technical Specification Surveillance Requirement 4.6.3.2a, " Containment isolation
Valves," requires that each containment isolation valve shall be demonstrated
operable at least once per 18 months, by verifying that, on a Phase A isolation test
signal, each Phase A isolation valve actuates to its isolation position.
The inspector reviewed Test Procedures PPT S2 7414A and PPT S2 74158 and
verified that the procedures tested that the containment isolation valves would
actuate to their isolation positions on a Phase A isolation test signal. The inspector
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verified that the test procedures had been implemented, as required, by the
Technical Specification surveillance.
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Maintenance Staff Training and Qualification
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MS.1 Breaker Refurbishment Trainina
a.
Insoection Scope (62707)
The licensee established an objective of refurbishing all Breakers 480 V and 6.9 kV
on a 10 year cycle and had begun refurbishment of nonsafety relattd breakers, As
part of this initiative, the licensee had technical service representatives for both
styles of breakers come to the site and provide hands on maintenance training for a
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period of 2 weeks. The service representatives instructed plant personnel on how
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to overhaul and refurbish the breakers to factory specifications. The inspector
observed a portion of this training and talked with all responsible parties,
b.
Observations and findinna
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Training, maintenance, quality control, and procedure development personnel
attended this training so that all groups could interact to develop a coordinated
maintenance effort. All groups were in the training workshop and were interacting
to ensure that maintenance procedures training guidelines, and maintenance
practices were correctly developed. A adeo camera was being used to capture
information for future training classes,
c.
Conclusions
The inspector concluded that this coordinated activity was an outstanding tool since
it integrated the various groups responsible for development and implementation of
the breaker refurbishment task.
Ill. Ena!nniing
E1
Conduct of Engineering
E1.1
ECCS Throttle Valves
a.
Inspection Scope (3751U
On October 2,1997, the licensee initiated a 1 hout report to the NRC under
10 CFR 50.72(b)(1)(ii)(B) for being outside the design basis. The licensee had
identified that two ECCS valves in each unit may have minimum openings less than
the fine mesh opening in the ECCS sump screens. The IWo.isco estimated that the
minimum gap in the cold leg injection valves associated with the centrifugal
charging pumps could be less than 0.0625 inches while the ECCS sump screens
have a fine mesh opening of 0.115 inches.
The inspector reviewed the licensee's operability determination and the
circumstances su< rounding the identification.
b.
Observations and Findinns
The licensue br9 completed a detailed review of recent industry concerns involving
ECCS throttle valves on August 19,1996, included in the reviews were the
potential clogging of ECCS throttle valves at Diablo Canyon, the potential ECCS
pump runout due to throttle valve erosion caused by high pressure drop induced
cavitation at Sequoyah, and a Westinghouse Nuclear Safety Advisory Letter
concerning erosion of globe valves in ECCS throttling applications. Using estimated
valve positions derived from flow measurements and misleading information
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supp'ied by the vendor, the licensee had determined that the minimum seat to-disk
clearance for two of the centrifugal charging pump cold leg injection lines was
greater than 0.110 inches. The ECCS sump screens are constructed of both coarse
and fine mesh. Because the openings in the fine mesh are 0.115 inches, the
licensee concluded that operability of the injection lines was unaffected by potential
clogging concerns but continued to review the erosion issue.
During a meeting with the vendor in September 1997, the licensee recognized that
the minimum gap in the throttle valve rnay not occur between the seat and the disk.
Instead, the minimum gap could occur between the valve body and the disk
antithrust guide rings. The guide rings help to position the disk within the valve
and, thereby, reduce side thrust and disk wobble problems. The licensi e
re evaluated their earlier conclusion concerning minimum clearance usin1 graduated
ball bearings and a spare valve. The licensee determined that, while the minimum
seat to disk clearance may be greater than 0.115 inches, the guido rir.g to body
clearance may be as small as 0.0625 inches.
The inspector reviewed the licensee's technical evaluation of operability. Based on
the expected low velocity of the water entering the sump, the licensee concluded
that debris likely to pass through the emergency sump screen and, which could be
larger than the throttle valve openings, would likely be fragmented by the residual
heat removal pumps and the centrifugal charging pumps prior to reaching the
throttle valves. Any unfragmented pieces reaching the valves would likely be
fragmented by the high differential pressure across the valve. Heavier objects,
which were unlikely to be fragmented, were expected to settle out of the water and
not enter the sump. The inspector found the licensee's evalJation appropriate.
At the exit meeting, the licensee informed the inspector that they expected to be
able to implement a design change to resolve the problems of thro *tle valve erosion
and clogging during the next Unit 1 refueling octage which was scheduled to start
during March 1998,
c.
Eqnclusions
The licensee identified that two valves in each unit may have minimum gap
openings which are smaller than the mesh on the ECCS sumps. The licensee had
previously evaluated the industry information cencerning the throttle valves but their
original evaluation did not consider the disk guido rings and f ailed to recognize that
the minimum gap between the guide rings and the valve body could be smaller than
the disk to seat opening.
The licensee was committed to resolving the ECCS throttle valve issues. The
licensee expected to be able to implement a design change during the next Unit 1
refueling outage starting in March 1998.
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E3
Engineering Procedures and Documentation
E 3.1
(Closedl Unresolved item (URI) 50-445/9717 05:50-446/9717 05: control room
emergency pressurization unit left above the design basis flow rate. This item was
lef t unresolved to determine the significance of leaving the flow above the
calculation limit and to deterrnine whether the other train was inoperable during the
time period when the as left flow was greater than 800 cfm.
a.
Lnspection Scone f 37551. 92903)
The inspector reviewed Calculation 058, " Control Room LOCA lloss of coolant
accident) Dose Analysis," Revision 1, to determine what effect an as ' eft value of
817 cfm had on dose. The inspector also reviewed the licensee's findings
concerning the operability of the opposite trein.
b.
Observations and Findinas
The inspector fc,und that the dl a,ince in dose to control room operators during a
design basis loss of coolant accident was minimal and did not exceed 10 CFR Part 50, Part A, General Design Criterion 19 limits. The inspector noted that the
licensee had used a value of 888 cfm (highest rneasured flow) to conclude that the
pressurization unit would not have caused control room operators to exceed dose
limits during a design basis accident. This value was chosen to encompass the two
identified time periods where the as left value for flow was 817 cim. The inspector
concluded that this was appropriate.
The inspector reviewed Surveillance Test Procedures PPT SX 7520A, " Control
Rcom Ventilation Filter Test CPX VAFUPK 21," Revision 0, and PPT SX 7522B,
" Control Room Ventilation Filter Test CPX-VAFUPK 22," Revision O. These
procedures tested the control room filtration units in accordance with Technical
Specification Surveillance Requirements 4.7.7.1b,4.7.7.1d, and 4.7.7.1g and h.
Each surveillance required pressurization flow rate to be 800 cfm plus or minus
10 percent. The acceptance requirement of 720 - 880 cfm was incorporated into
each procedure. However, because the dcsign basis calculation assumed 800 cim,
any value above 800 cfm would be outside the design basis.
10 CFR Part 50, Appendix B, Criterion V, requires, in part, that activities affecting
quality be prescribed by documented instructions of a type appropriate to the
circumstances and that the instructions include quantitative acceptance criteria for
determining that important activities have been satisfr.ctorily accomplished. The
accepta. ice criteria used in Procedures PPT-SX 7520A and PPT SX 7522B was
inadequate because the values allowed operation of the pressurization units outside
the design basis calculation and did not account for measurement uncertainty. This
was a second example of a violation (50-445/9718 03; 50-446/9718 03,
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On September 30, the licensee informid the inspector that they had determir1d
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that, during the time that Train A had an as left flow value of 817 cfm (September
11,1994, through January 12,1996), Train B had been inoperable seven times for
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a total of 5 days,23 hours2.662037e-4 days <br />0.00639 hours <br />3.80291e-5 weeks <br />8.7515e-6 months <br />, and 10 minutes. During the time that Train B had an
as left flow valve of 817 cfm (July 15,1996, through August 8,1997), Train A bad
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been inoperable once for 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and 31 minutes. The licensee informed the
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inspector that they intended to submit a supplement to their LER 50 445/97 006
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which described the two porlods when the flow was lef t above design values. The
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inspector concluded that this was appropriate. -
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c.
' Conclusions
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Failure to incorporate design basis values for the control room pressurization units
into surveillance test procedures led to leav!ng the flow rates above the design basis
on two occasions. This was a violation. The allowed range for flow would not
have caused control room operators to exceed allowable dose limits during a design
basis accident.
E4
Engineering Staff Knowledge and Performance
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E4.1
Failure to Follow Procedures for Temperature Measurina Device Accuracy
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a.
Insoection Scope (37551)
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As part of the followup to URI 50 445/9717 05;50 446/9717 05 and Followup
ltem 50-445/9717 02; 50-446/9717 02, the inspector reviewed the completed
Surveillance Work Order 5 97 501021 AA used to implement, Procedure PPT SX-
7505A, " Control Room Pressurization Test Train A," on August 8,1997. The
inspector compared the accuracles of the test equipment to procedural
requirements,
b.
Observations and Findinas
Section 7.0, " Test Equipment," of the surveillance test procedure required a
temperature indicating device with an accuracy of 12'F. Section 7.0 of
Attachment 1 listed that Thermometer IC1473 was used during the test. The
inspector found that the accuracy of Thermometer IC1473 was 12.2'C
(approximately 14.0'F). Technical Specification 6.8.1 requires, in part, that the
licensee establish,~ implement and maintain procedures covering the activities
referenced in Appendix A of Regulatory Guide 1.33, Revision 2, February 1970.
Appendix A requires specific procedures for each surveillance test listed in the
Technical Specifications. The failure to use a temperature measuring device with
the required accuracy is a violation of these requirements (50 445/9718 04;
50-446/9718 04).
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' The licensee evaluated the latest surveillance test results and concluded that the-
as lef t flow values for both pressurization trains were still below design basis limits
when the larger uncertainty was assumed in the calculation. The inspector
concluded thtt, while the failure to follow procedures had a low safety significance,
it represented poor attention to detail by the engineers.
E8
Miscellaneous Engineering losues
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E8.1
IClosed) Violation 50-446/9715 02: failure to translate design basis into drawings
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for a containment pressure relief valve mechantcal stop, in the enclosed Notice to
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NRC Inspection Report 50 445/9715; 50 446/9715, the NRC concluded that the
information regarding the reason for the violation and the correctNe acVons taken
and planned were already adequately addressed on the docket and that a response
was not necessary unless the licensee concluded that the descriptions or corrective
actions did not a.acurately reflect their position. The licensee did not respond and
this item is closed.
IV. Plant Suonort
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Radiological Protection and Chemistry (RP&C) Controls
During plant tours, the inspector determined by direct observations in selected steas
that posting and labeling was in compliance with regulations and licensee
procedures. The inspector verified, at least weekly, that chemistry samples were
within Technical Specification and industry guideline limits.
V. Man,agement Meetinas
X1
Exit Meeting Summary
The inspector presented the results of the inspection to members of licensee management
at the conclusion of the inspection on October 16,1997. The licensee acknowledged the
inspector's findings. No proprietary information was identified.
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ATTACHMENT
SUPPLEMENTAL INFORMATION
PARTIAL LIST OF PERSONS CONTACTED
Licensu
R. C. Byrd, Manager, Smart Team 2
J. J. Kelley, Vice President, Nuclear Engineering and Support
D. R. Moore, Manager, Operations
A. H. Saunders, Supervisor, Testing
C. L. Terry, Group Vice President, Nuclear Production
INSPECTION PROCEDURES (IPs) USED
IP 37551:
Onsite Engineering
IP 61726:
Surveillance Observations
IP 62707:
Maintenance Observations
IP 71707:
Plant Operations
IP-71750:
Plant Support Activities
- IP 92901:
Followup Plant Operations
IP 92902:
Followup Maintenance
IP 92903:
Followup - Engineering
ITEMS OPENr.D AND CLOSED
Opened
50 445(4461/9718 01
NCV Safety evaluation not performed for procedure change
50 445(446)i9718-02
IFl
Review of seismic evaluation of test skid connection
50-445(446)/9718 03
Inadequate procedures for hydrogen recombiner
surveillance and control roorn pressurization surveillance
50 445(446)/9718-04
Failure to use temperature instrument with the accuracy
required by procedure
Closed
50-445(446)/9718-01
NCV Safety evaluatine not performed for procedure change
50-445/95007
LER
Engineered safety taature ic tr 'on caused by
feedwater recirculation vana ! .,ure
50-446/9715 01
Operation in excess of.102 percent thermal power
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50 446/9715-02
Failure to translate design basis into drawings for
containment pressure relief valve mechanical stop
50 4451446)/9717 05
Control room emergency pressurization unit left above
the design basis flow rate
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