ML19352B231
| ML19352B231 | |
| Person / Time | |
|---|---|
| Site: | Zion File:ZionSolutions icon.png |
| Issue date: | 04/30/1981 |
| From: | Hayes D, Kohler J, Waters J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML19352B186 | List: |
| References | |
| 50-295-81-06, 50-295-81-6, 50-304-81-04, 50-304-81-4, NUDOCS 8106030489 | |
| Download: ML19352B231 (15) | |
See also: IR 05000295/1981006
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U.S. NU0 LEAR REGULATORY COMIISSION
OFFICE OF INSPECTION AND ENFORCDIENT
REGION III
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Report No.
50-295/81-06, 50-304/81-04
Docket No.
50- 295/304
Licensee:
Commonwealth Edison Company
P. O. Box 767
Chicago, IL 60690
Facility Name:
Zion Nuclear Power Station, Units 1 & 2
Inspection At:
Zion Site, Zion, IL.
Inspection Conduqted:
Fe ruary 28, 1981 to April 15, 1981
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Inspectors:
J. E. Kohler
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J. R. Waters
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Approved By:
D' W. Ha
Chie
Reactor Projects Section IB
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Inspection Summary
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Inspection on February 28-April 15,1981 (Report No. 50-395/81-06; 50-304/81-04)
Areas Inspected: Routine unannounced resident inspection of licensee actions
on previous items, reactor operations, operator logs, operational safety
verification, monthly maintenance observation, monthly surveillance observation,
LER follow-up, Unit 1 Containment Integrated Leak Rate Test (CILRT), radio-
active gas releases, containment posting for respiratory protection, containment
purging, reactor coolant system 1cvel surveillance during refueling, power
operated relief valve block valves, unplanned radioactive releases, calibration
of containment high range iad monitors, and boron injection tank leakage. The
inspection involved 434 hours0.00502 days <br />0.121 hours <br />7.175926e-4 weeks <br />1.65137e-4 months <br /> onsite by two NRC inspectors including 51 hours5.902778e-4 days <br />0.0142 hours <br />8.43254e-5 weeks <br />1.94055e-5 months <br />
onsite during of f-shif ts.
Results: Of the areas inspected one item of noncompliance (Improper adjustments
during the CILRT, Paragraph 5.C.(2)) was identified.
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Persons Contacted
- K. Graesser, Station Superintendent
- G.
Plim1, Administrative and Support Services
Assistant Superintendent
- E. Fuerst, Unit 1 Operating Engineer
- J. Gilmore, Unit 2 Operating Engineer
- P. Kuhner, Quality Assurance Engineer
R. Budowle, Assistant Technical Staff Supervisor
- F.
Lentine, Test Director ILRT
A. Ockert, Test Director ILRT
Z. Gajic, Technical Staff Engineer
A. Amoroso, Technical Staff Engineer
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J. Joosten, Technical Staff Engineer
K. Kovar, Teci nical Staff Engineer
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- R. Rostkowski, Quality Assurance Engineer
D. Howard, Rad-Chem Supervisor
J.16rianyi, Operating Engineer
R. Shannon, ISI Co-ordinator
F. Ost, Health Physics Engineer
- Denotes those present at management exit of April 15, 1981
2.
Licensee Actions on Previous Inspection Findings
(closed) Unresolved item (295/80-20-01, 304/80-20-01) : Reactor Coolant
System Leakage. The licensee has modified the computer program used to
measure reactor coolant leakage. The modified program trends pressurizer
relief tank level and volume control tank level.
3.
Summary of Operations
Unit I remained in cold shutdown the entire reporting period. The
cold shutdown conditio0 was extended past the estimated sixty-six day
refueling outage which began on January 15, 1981 due to unexpected
maintenance modification work required on the Boron Injection Tank
(See Paragraph 14), Boron Injection Tank discharge valves, and 1C reactor
coolant pump seals. The containment integrated leak rate test was success-
fully completed (See Paragraph 4).
Unit 2
The unit operated at power levels up to 93%. Reactor power was limited
due to isolation of one of the low pressure feedwater heater strings
because of tube leakage.
Three unscheduled reactor shutdowns occurred:
a.
On Nbrch 5, 1981 the unit tripped from 93% power on low low steam gen-
erator C level due to an instability which developed in the 2B feed-
water pump. Attempts at sterting the redundant motor driven feed pump
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and feeding the steam generators were unsuccessful when the air supply
~1ine to the feedwater pump discharge valve broke.
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The unit returned to power on March 6, 1981
b.
The unit tripped from 93% power on March 11, 1981 on low low steam
generator C level due to a trip of a motor control center which~ supplied
power _to the 2B feedwater pump oil pump. The motor control center tripped
when a contractor working on the Three Mile Island modification for the
Technical Support Center drilled into a cable on the turbire floor.
The unit returned to power on March 11, 1981
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c.
The unit tripped from 93% power on April 3,1981 on low low steam
generator C level caused by a sudden decrease in feedwater pump 2B
flow. The low feedwater flow condition was caused by a trip of a
motor control center which supplies power to the M/A station. When
the motor control center tripped several other functions were lost.
The motor control center tripped due to an instantaneous trip signal
which developed in a 120 volt lighting circuit beine worked on for a
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Three Mile Island modification. The motor control center tripped
before the local breaker at the 120 volt lighting circuit.
The unit returned to power on April 4,1981.
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4.
Containment Integrated Leak Rate Test
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The second periodic Zion Unit 1 Containment Integrated Leak Rate Test
(CILRT) was performed during the perica from March 3,1981 to Nkrch 12,
1981
At the conclusion of the Type A portion of the CILRT, a twelve
hour period from Nhrch 11,1981 at 3 PM to March 12, 1981, a t 3 AM,
containment leakage at a reduced pressure of 25PSIG was measured to be
.0157 W/0/ day and .0228 W/0/ day at the 95% upper confidence level.
Technical Specification 4.10.b imposes the requirement that the CILRT
Type A test at reduced pressure not exceed .0729 W/0/ day.
App <ndix J requires that the Type A leakage race not exceed 75% of
0729 W/0/ day or .0547 W/0/ day. Inspector review of the procedure,
the events log, the containment mass plots, and leakage calculation,
and instrumentation calibration, as well as independent calculation
made by the inspector indicates that all acceptance criteria were met.
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At the conclusion of the Type A test, a supplemental test was conducted
by inducing a leak rate equivalent to 2.25SCFM or .0417 W/0/ day. This
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established acceptance cr!'.eria for the supplementai test of (.0157 +
.0417) i .0182 W/0/ day or (.0393, .0757 W/0/ day) . At the conclusion of
the supplemental test the licensee neasured .0422 W/b/ day which, therefore,
verified the accuracy of the Type A measurement.
No items of noncompliance were identified.
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- During preliminary portions of the test, before the official twelve
hour test of record, containment leakage exceeded the acceptance criteria.
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Investigation into the causes of excessive containment leakage .resulted
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in procedure changes and system isolations not previously required by-
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procedure. ^ 2ach of the procedure changes along with the effect on the
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test will be discussed in Paragraph 5.-
The licensee understands that the
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measured results stated above (.0157/.0228 W/0 day) will have to hi adjusted
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prior;to the requirement ,for containment integrity by specified it: ems in
Paragraph 5, such that the combined sum of the measured plus the adjust-
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ments is less than .0547 W/0/ day. .13ue post test adjustments wili be re--
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ported to the Commission in the required 90 day report, and are contained
in Paragraph 6 of this report.
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While all applicable acceptance criteria were met in the official portion
of the test, one specific leakage path developed'as a direct result of
the Type A test which required immediate maintenance action.- This leakage
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path developed through seals of both innter and outer airlock door shaf ts.
Because maintenance needed to be performed on the airlocks in order to
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successfully complete the Type A test, 10CFR50 Appendix J, Section III.
A.(a) classifies the initial attempt at messaring the leakage rate a '
failed test.- .The significance of a failure during a Type A test relates.
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to future testing frequency. In the case of the first periodic failure,
the test schedule applicable to subsequent Type A tests shall be reviewed
and approved bv the Commission.
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Inspector review of past Type A tests prior to the present test revealed
repetitive problems with maintaining leak tightness of airlock doors
around the shaf t s'als.
During preliminary-planning for the present
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test, the licensee was utged by the inspector to make every attempt to
ensure airlock leak tightness. However, even with increased licensee
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attention, the airlock began leaking sufficient to require immediate
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remedial maintenance. Therefore, the inspector requested the licensee
to propose an airlock improvement program. The results of this improvement
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program are contained in Paragraph 7, Airlock Improvement Program.
Since the leakage was corrected during the test and licensee has proposed
immediate remedial action to ensure airlock integrity, the as scheduled
Type A test frequency is acceptable with no accelerated Type A testing
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required. Should the next scheduled Unit 1 Type A test fail to meet
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acceptance criteria, and this failure was directly attributable to the
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Type A test, accelerated. Type A testing would be required as specified
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10CFR Appendix J,Section III.6.(b).
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5.
In Place Type A Test Adjustments
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During performace of _ the Type A test, measured leakage in excess of that
which is al'owable was experienced. In order to determine the location of
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the leakage and correct it, several procedure changes were made whereby
some vented s mtems were cut and cappcJ, isolation valve sea' water was
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injected, the airlock was sealed with temporary closure devices, the main
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steam lines and steam generators were pressurized, heat tracing to purge
valves was reconnected, and some sample lines were flanged. The following
sections describe tha disposition of each of these' adjustments:
a.
Systens That Were Isolated:
(1)
Portions of the penetration pressurization (PP) system and
instrument air system, were cut and capped in order to
positively isolate a possible containment leakage path
through the inboard isolation valve and out through PP
System. The cap was necessary because the PP system could
not be positively isolated from the renetration.
Normally a temporary closure device such as a cap would
require a post Type A Local Leak Rate Test (LLRT) and an
adjustment to measured Type A results. However, because
the PP system is designed as an Engineered Safety Feature
(ESF) function supplying sesling air to selected containnent
penetrations, it was isolated for test measurement purposes
only. Consequently, portions of the PP system that were cut
and capped for the purposes of the 1981 Type A test do not
require post Type A test LLRT adjustments.
(2)
Unfinished portions of the Three Mile Island containment
wide range pressure modification were found leaking during
the Type A test such that isolation by a temporary closure
was required. Since this penetration would always be expected
to be in service, temporary closure will require a post Type A
LLRT (10CFR50 Appendix J, Section III.A.S.(b)). The results
of the as lef t penetration leakage along with other test
adjustments must be added to the final measure CILRT leakage
rate of .0157 W/0/ day. The total sum must be less than .0547
W/o/ day.
The licensee performed the required LLRT on the Three Mile
Island wide range pressure modification with the leakage
measured to be 0.0 W/0/ day at a pressure of 48 PSIG. The
value was added into the TYPE A results (See Paragraph 6,
Adjusted Type A Results) .
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The licensee verified that the equivalent modification on
Unit 2 was leak tight.
The inspector has no further questions regarding this item
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and no items of noncompliance were identified.
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(3)
The Containment Press e and Vacuum Relief Line contains two
containment isola tiot valves 1RV0005 and IRV0006 which were
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known to leak air prior to the Type A test. The valves could
not be made to hold air and the line was flanged closed prior
to the CILRT. The station elected to demonstrate positive
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isolation of this'line by relying on the installed Isolation
Valve Seal Water System (IVSW) which supplies high pressure
water to valve spaces between redundant isolation valves (See
Paragraph 5.c.(1) .
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Prior to the need for containment integrity, .the licensee
must demonstrate that 1RV0005 and 1RV0006 are water tight
and that the check valves in the IVSW header are operable.
The licensee- demonstrated valves 1RV0005 and 1RV0006 were
water tight and the associated IVSW check valves were operable
prior to the need for containment integrity.
The inspector has no further questions regarding this item
and no items of noncompliance were identified.
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(4)
Filters cantained in the Unit 1 primary sample systems were
blank flanged during trouble shooting portion of the test.
These flanges'were left in place during the entire test.
After the Type A portion of the test was concluded, the automatic
containment isolation valves associated with the sample lines
that were flanged were made leak tight. The results of the as
lef t local leak rate tests perforued were added to the final
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Type A test results (See Paragraph 6, Adjusted Type A test
results).
No items of noncompliance were identified and the inspector
has no further questions regarding this item.
b.
Airlock Temporary Closure
Both inner and outer airlock doors developed a containnent leak at
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the point where shaf ts for remote door opening penetrate the airlock
doors. The Icakage condition was such that a temporary closure was
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required. Because this leakage resulted directly from the Type A
test and was not experienced during the most recent integrated leak
rate test performed on the airlock, the leakage condition caused
the initial attempt at the Type A test to be classified as a failure
consistent with 10CFR50 Appendix J III.A.(a) .
Since the airlock is designed to be a containment barrier, the t cmp-
orary closure will require a post Type A Integrated Airlock Leakage
Test prior to the need for containment integrity performed at full
and reduced pressure. The results of the as left airlock leakage
test at reduced pressure must be added to the final measured CiLRT
leakage rate of .0157 W/0/ day along with other test adjustment
additions. The sum total of CILRT neasured leakage and adjustments
must be less than .0541 W/0/ day.
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The licensee performed the required integrated airlock leakage test
. with the leskage measured to be .00006 W/0/ day at a pressure of 47
PSIG. The value was added to the Type A results (See Paragraph 8,
Adjusted Type A Results).
No items of noncompliance were identified.
c.
Systems Pressurized During Type A Test
The licensee has committed to ANSI-45.4, Leakage-Rate Testing of
Containment Structures for Nuclear Reactors. Section 4.6 states in
part that, ......" lines and vessels containing fluids that are or
may become pressurized should be depressurized and valved off outside
the containment to preclude accidental addition of fluids to the con-
tainment during the test.
While the initial station CILRT procedure made provisions for isolating
pressurized systems outside containment, two procedure changes were
implemented during the CILRT which introduced pressurized systems
into containment. These procedure changes were enacted while the
station was trouble shooting the initial excessive containment leakage
condition:
(1)
Isolation Valve Seal Water System (IVSW)
This system, classified as seal system by 10CFR50 Appendix J,
is described in the ESF section of the Final Safety Analysis
Report. As such, isolation valves getting iVSW injection do
not require Type C local leak rate tests. Becausa the IVSW
water injection into the valves provided an additional barrier
against containment leakage, the licensee committed to perform
additional testing consistent with the In-Service Inspection
Program to ensure the check valves in the IVSW headers were
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The required tests, contained in Technical Staff Surveillance-88,
were performed prior to the need for containment integrity and
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demonstrated check valve operability.
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The inspector 1:as no further questions regarding this item and
no items of noncompliance were identified.
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(2)
Pressurized Main Steam Headers and Steam Generators
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During trouble shooting the excessive containment leakage condition,
the steam generators and steam lines were p cessurized. This procedure
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was terminated when a definitive leak was found through the
containment purge valves due to inoperable heat tracing (See
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Paragraph 5 d.)
However, the steam generators and lines were
lef t pressurized at various pressures.
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During the official data taking portion of the Type A test, from
Nkrch 11,1981 at 3 PM to Fhrch 12, 1981 at 3 AM, the licensee
reduced the 1A main steam line header pressure on March 11, 1981
at 10:30 PM. While the adjustments to the header pressure did
not appear to have any definitive effect on the e.ontainment mass
plot, adjustments made during official testing are in violation of
Onecifically 10CFR50 Appendix J Section III.A.a
states in part that, "during the period between the initiation of
the containment inspection and performance of the Type A test, no
repairs or adjustments shall be made so that the conte.inment can
be tested in as close to the "as is" condition as peasible". This
is considered an item of noncompliance of Severity Level V.
d.
Systems That Were De-energized
During final stages of trouble shooting the heat tracing to the
purge valves was found to be de-energized. This, in conjunction
with the cold outside air, caused the valves to leak. The heat
tracing was re-energized and the valves were made to seat.
The licensee has initiated a modification to ensure that the purge
valves are not subjected to cold outside temperatures. The modifica-
tion involves constructing an enclosure around the outboard valve.
No further action needs to be taken other than expeditious completion
of the modification. The inspector has no further questions regarding
this item and no items of noncompliance were identified.
6.
Adjusted Type A Test Results
The following list summarizes the results of post Type A local leak
rate tests and their effect on the Type A test results:
COMPONENT
LEAKAGE W/0/ Day
Three Mile Island Wide Range Pressure Modification
0.00
Airlock
0006
Containment Isolation Valves in the Sample System
.000352
Total
.000417
Final Type A Test Results
.0157
Sum of Total and Final Type A Test
.0161
The inspector concludes that the adjusted Type A test results meet all
acceptance criteria.
The inspector has no further c,uestions regarding this 1. tem and no items
of noncompliance were identified.
7.
Airlock Improvement Program
The airlocks and escape locks and equalizing valves on both Unit 1
and Unit 2 have a repetitive history of developing leakage during
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performance of the Type A tests. Because the Icakage has caused difficulty
during Type A testing and has resulted in the containment leakage exceeding
allowable lindts, an improvement program has been established and is des-
cribed below:
Licensee Commitmerts for Minimizing Personnel
and Esecpe Hatch Leakage
on . Increase the local leak-rate test duration to one hour allowing
forty-five minutes for stabilization,
b.
Initiate preventive maintenance schedule for shaf t seals and
equalizing valves:
(1) Rebuild all equalizing valves (two persennel and two
escape) each refueling outage.
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(2)
Replace all shaf t seals every other refueling outage.
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(3) Torque the packing on shaft seals each refueling outage.
c.
The local leak rate test should be performed following any
maintenance on the hatches as described under item (b).
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d.
Evaluate new hatch designs or seal designs.
The inspector has no further questions regarding this item and no items
of noncompliance vere identified.
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8.
Type B and C Leakage Results
The results of the licensee's Type B and C leakage testing indicates
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that the sum of the leakage meets the acceptance criteria specified by
Technical Specifications and 10CFR50 Appendix J.
No items of noncompliance were identified.
9.
Power Operated Relief Valve Block Valves (PORV)
The resident inspectors received a request for information from the
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regional office concerning Westinghouse PORV block valves with the
designation 3GM-88. These valves were found not to 6 9 capable of
closing against full system pressure.
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Zion Station has no Westinghouse 3GM-88 block valves installed or in
the warehouse.
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The inspector has no further questions regarding this item.
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10. Allowable Duration of Containment Purging
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The resident inspectors clarified a requirement regarding the allowable
amount of time annually that either Unit 1 or Unit 2 can be purged using
48 inch purge valves. The licensee was under the impression that the NRC
had restricted purging on each unit to a maximum of ninety hours yearly.
The resident inspector discussed the criteria for purging with the NRC
operating project manager. It was determined that the ninety hour purging
restriction was no longer in effect. The only current restrictions applicable
to Zion Generating Station are contained in a letter dated January 15, 1981
from S. Varga, Chief Operating Reactors Branch #1, Nuclear Regulatory
Commission to J. S. Abel, Director of Nuclear Licensing, Commonwealth
Edison Company.
11. Alpha Concentration in Excess of 10CFR Appendix B
On March 30,1981 at 0900 a Zion Station Radiation Protection Technician
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telephoned the Region III office stating that alpha activity in Unit 1
containment was in excess of 10CFR50 Appendix B limit of 2.0xE-12 micro-
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curies per cubic centimeter. He alleged that the licensee was reluctant
to post the containment airborne requiring half masks. He indicated that
only af ter continual prodding on his part did station management post the
containment airborne.
The inspector investigated the circumstances involved and interviewed the
station health physicist and chemist. According to the station management,
the 0900 containment air sample on March 29, 1981 (the previous day)
showed elevated (6.85xE-12 micro-curies per cubic centimeter) alpha in
excess of 10CFR Part 20 Appendix B.
Station Procedure RP-1310-11,
" Posting Areas for Airborne Contamination", requires posting for
respiratory protection when alpha activity is above 2xE-12 micro-curies
per cubic centimeter af ter twenty-four hours decay. Af ter twenty-four
hours decay, the previous day's sample measured 2.5xE-12 micro-curies
per cubic centimeter at about 0900 on March 30, 1981. The licensee re-
sampled for alpha and had a management meeting. At 0915 to 0920 station
management posted the containment airborne. The twenty-minute delay in
posting the containment airborne was caused by the management meeting
and the resample.
(The resample was counted for five minutes and showed
elevated alpha concentration). It was determined that a resample was
necessary because of the low counting efficiency for alpha radiation ex-
perienced by the licensee's equipment (4%).
The inspector verified through shif t logs that containrent purging was
terminated at 1000 on March 30, 1981
The licensee investigated the cause of the low counting efficiency on
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March 30, 1981 and attributed it to improper sample preparation resulting
in an ultra conservative calibration (counting equipnent indicating higher
concentration than actually existed). A porous fiber filter had been
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used as a base for the sample. This caused. the alpha radiation to be
absorbed in the filter rather than in the counting medium. Af ter checking
with the manufacturer, a glass fiber filter base was used and the instrument
recalibrated to an efficiency of 107..
This resulted in the alpha ~ airborne
concentrations returning to below 10CFR50 Appendix B criteria and the contain-
ment airborne posting was removed.
Af ter the containment posting for airborne on March 30, 1981, seve ral
workers who were in the containment complained that they were not notified
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of the. airborne condition until they exited. The individuals requested
and received additional counting for internal contamination. No evidence
of internal contamination was found.
No items of noncompliance were identified.
12. 0-R-14 Alarm of Mar ch 18, 1981
At 0831 on March 18, 1981 a high radiation alarm was received on monitor
0-R-14 (auxiliary building vent gaseous monitor) .
Monitor 1RT-PR-25, which
also monitors the auxiliary building vent gaseous activity showed a concomitant
increase. Investigation by the licensee could produce no apparent cause
for the alarm. A second alarm on 0-R-14 was received at approximately
1400 the sane day and operating personnel were able to correlate this alarm
with a venting operation on a temporary differential pressure cell installed
on the volume control tank. Research indicated that the venting operation
had aleo been performed at about 0830 and was the probable cause of the
first Siarm. Calculations by the licensee showed that both releases were
only a small percentage of the maximum allowed by technical specifications.
NRC headquarters in Bethesda was notified by Emergency Notification System
of both releases.
No items of noncompliance were identified.
13. Clarification of _High Range ?sdiation Monitor Calibration Requirements
In response to licensee inquiries, the inspector determined, through
conversation with the licensing project manager, that electronic calibration
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is acceptable in fulfilling the requirements of Table II F.1-3 of Nureg-
0737 for the range of 10 to 103 R/hr.
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No items of noncompliance were idcatified.
14.
Boron Injection Tank Ima[73e (BIT) Unit _1
On March 2,1981 while attempting to correct what was thought to be boron
injection tank manway seat leakage, personnel discovered leakage from a
3/8 inch diameter hole drilled in the carbon steel pressure vessel per-
pendicular to the manway centerline. Investigation revealed this to be
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a test hole penetrating through the carbon steel up to the stainless steel
sleeve or liner on the inside of the manway opening. The hole is used for
liner testing during tank fabrication. Leakage out this test hole indicated
a breach of the stainless steel liner. Drawings showed similar test holes
on the BIT inlet and outlet nozzles. These were checked and found to be
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leaking also. Concern over the effect of boric acid on the carbon steel
pressure vessel and the desire to evaluate the rechanism of the liner
failure led to the licensee's decision to replace the BIT. An all stainless
steel vessel was found to be available from the Braidwood Station. The
BIT replacement was complete by April 2,1981, and resulted in a twenty-four
day extension of the refueling outage.
The old BIT was dissected for examination. Pentrations were found in the
cylindrical manway liner wall and in the weld joining the liner to the
manway seating surface. The most severe area of degradation of the carbon
steel occurred underneath the penetration in the liner wall. Here the
boric acid had corroded a crater approximately 1 1/2 inches in diameter
by 5/16 inch deep in the carbon steel. Channels from this area anu from
the weld penetration lead to the test hole. Preliminary results from samples
sent to Westinghouse indicate intergranular corrosion attack in the area of
the liner penetration and transgranular corrosion cracking in the area of the
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weld penetration. Possible causes for these types of attack are sensitization
of the stainless steel during heat treatment of the vessel and impurities
in borated water.
As documented in LER 50/295/81-08 detailed investigations are still in
progress and the licensee will upvate the LER when the final report is
received.
On April 3, 1981, the test holes on the Unit 2 BIT were inspected and no
evidence of leakage was found. At this time the licersee plans no further
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action on Unit 2 BIT until the scheduled refueling outage in September
of 1981.
Submittal of the final report on the results of Unit 1 BIT examination
is designated as Open Item 50-295/81-06-01.
15. Operation of the Reactor Coolant System (RCS)
During the Unit I refueling outage a differential pressure detector was
connected to RCS piping to provide remote RCS water icvel indication.
The signal from this differential pressure cell is fed to a pen recorder
in the control board, and to the meter which normally indicates uncom-
pensated pressurizer level. The calibration is such that the lower end
of the meter and recorder scale corresponds to a level slightly below
the nozzle centerline. A prerequisite of the containment integrated leak
rate test requires that the RCS be filled to at least 80% of pressurizer
level. Operators established this level using the uncompensated pressur-
izer level meter not realizing that it was connected to the temporary
RCS d/p cell. This misconception existed during at least two shifts.
The error was discovered and corrected prior to the start of the leak
rate test. The procedure for installation of the temporary level indi-
cating system has been modified to require that caution stickers be placed
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on the uncompensated pressurizer level mete acting that it indicates
RCS level.
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No items of noncompliance were identified.
16. Review of Plant Operations - Startup
The inspector reviewed the licensee's administrative controls governing
Unit I return to operation from the refueling outage. The prerequisite
. list GOP-0 was reviewed for adequacy and for completion prior to 1 caving
cold shutdown and hot shutdown. Containment tours were performed to
verify cleanliness and general system status. The inspector attended the
onsite review meetings for both hot shutdown and start-up, in which all
outstanding items were evaluated for relevance to the particular event.
Compliance with various technical specification requirements for start-
up was verified by the inspector. Portions of the prestart-up surveillance
testing and approach to. criticality were witnessed and reviewed for ad-
herence to procedures and technical specifications.
No items of noncompliance were identified.
17. Operational Safety Verification
The inspector observed control room operations, reviewed applicable logs
and conducted discussions with control room operators during the months
of March and April,1981. The inspector verified the operability of
selected emergency systems, reviewed tagout records and verified proper
return to service of affected components. Tours of the euxiliary building
and turbine building and Unit 1 containment were conducted to observe
plant equipment conditions, including potential fire hazards, fluid leaks,
and excessive vibrations and to verify that maintenance requests had been
initiated for equipment in need of maintenance. The inspector by obser-
vation and direct interview verified that the physical security plan was
being implemented in accordance with the station security plan.
The inspector observed plant housekeeping / cleanliness conditions and
verified implementation of radiation protection controls. During the
months of February and April, the inspector walked down the accessible
portions of the containment spray systems to verify operability. The
inspector also witnessed portions of the radioactive waste system
controls associated with the shipment of spent resins from the Unit I
deborating demineralizer.
These reviews and observations were conducted to verify that facility
operations were in conformance with the requirements established under
technical specifications,10 CFR, and administrative procedures.
18. Monthly Maintenance Observation
Station maintenance activities of safety related systems and components
listed below were observed / reviewed to ascertain that they were conducted
in accordance with approved procedures, regulatory guides and industry
codes or standards and in conformance with technical specifications.
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The following items were considered during this review: The limiting
conditions for operation were met while components or systems were removed
from service; approvals were obtained prior to initiating the work;
activities were accomplished using approved procedures had were inspected
as applicable; functional testing and/or calibrations were performed
prior to returning components or systems to service; quality control
records were maintained; activities were accomplished by qualified
personnel; parts and materials used were propes.y certified; radiolo-
gical controls were implemented; and, fire prevention controls were
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implemented.
Work requests were reviewed to determine status of outstanding jobs and
to assure that priority is assigned to safety related equipment maintenance
which may affect system performance.
The fo11 ewing maintenance activities were observed / reviewed:
Unit 1: Boron Injection Tank
Unit 1: Boron Injection Tank Discharge Valves
Unit 1: Containment Wide Range Pressure
Unit 2 : Containment Wide Range Pressure
Unit 1: IC Reactor Coolant Pump
Unit 1: Reactor Vessel Level Indication
Following completion of maintenance on the IC Reactor Coolant Pump Seals,
the inspector verified that it had been retu:ned to service properly.
No items of noncompliance were identified.
19.
Monthly Surveillance Observation
The inspector observed the following required surveillance testing:
0 Diesel Generator Test, Boron Injection Tank Inlet and Outlet Valve
Leak Test, Volume Control Tank Level Instruments Test, Diesel Generator
Tests on 2A and 2B Units, Hot Rod Drop Tests, RTD Cross Check Tests, and
verified that testing was performed in accordance with adequate proce-
dures, that test instrumentation was calibrated, that limiting conditions
for operation were met, that removal and restoration of the affected
components were accomplished, that test results conformed with technical
specifications and procedure requirements and were reviewed by personnel
other than the indiridual directing the test, and that any deficiencies
identified during the testing were properly reviewed and resolved by
appropriate management personnel.
No iteme of noncompliance were identified.
20.
Licensee Event Reports Followup
Through direct observations, discussions with licensee personnel, and
review of records, the following event reports were reviewed to determine
that reportability requirements were fulfilled, immediate corrective action
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was accomplished, and corrective action to prevent recurrence had been
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LER NO.
Uni _1
80-20
Update on Cause of RTD Spiking Low
81-04
RHR Recirculation Valve Micro Switch Out of Tolerance
81-05
% Recombiners Found Not Interchangeable
81-06
Fire Sump Rad Monitor ORT-PR-25 Failure
81-07
Failure to Perform 50.59 Review
81-08
BIT Liner Leakage
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81-09.
Nissed Sample on Fire Sump
LER NO.
Unit 2
81-02
Purge Monitor Reading Low
81-03
Faulty Microswitch on RHR Recirculation Valve
.Regarding LER 50-295/81-08, see Paragraph 14.for details.
Regarding LER 50-295/81-09, this is considered a licensee identified item
of noncompliance in which no citation is issued.
No items of noncompliance were identified.
21.
Unresolved Items
Unresolved items are matters about which more information is required in
order to ascertain whether they are acceptabic items, items of noncompliance
or deviations. One unresolved item was disclosed during this inspection..
22.
Exit Interview
The inspector met with licensee representatives (denoted in Paragraph 1)
throughout the month and at the conclusion of the inspection on April 15,
1981 and summarized the scope and findings of the inspection activities.
The licensee acknowledged the inspector's comments.
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