ML20207K163
| ML20207K163 | |
| Person / Time | |
|---|---|
| Site: | McGuire, Mcguire  |
| Issue date: | 07/15/1986 |
| From: | Hosey C, Revsin B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML20207K116 | List: |
| References | |
| 50-369-86-15, 50-370-86-15, NUDOCS 8607290350 | |
| Download: ML20207K163 (9) | |
See also: IR 05000369/1986015
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pS K8Cg UNITED STATES
g #o NUCLEAR REGULATORY COMMISSION
[' n REGION il
3 j 101 MARIETTA STREET, N.W.
- ATL ANTA, GEORGI A 30323
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%, " * * *. / jut 16IN6
Report Nos.: 50-369/86-15 and 50-370/86-15
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Licensee: Duke Power Company
422 South Church Street
Charlotte, NC 28242 '
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Docket Nos.: 50-369 and 50-370 License Nos.: NPF-9 and NPF-17
Facility Name: McGuire
Inspection Conductec : June 3-5, 1986
Inspectors: j -h 7hI!Ob
Date Signed
B. Re9N/
Approved by: 7[/G b d
C. M. Hos6 # Section) Chief Dat'e Signed
Division of Radiatiorl Safety and Safeguards
SUMMARY
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Scope: This special unannounced. inspection involved onsite inspection during
normal duty hours in the area of external exposure control.
Results: One violation - failure to follow radiological protection procedures.
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1. Persons Contacted
- B. Hamilton, Superintendent, Technical Services
- J. Foster, Station Health Physicist
- W. Byrum, Health Physics Coordinator
- L. Lewis, System Health Physicist
- N. G. Atherton, Compliance
P. Huntley, Health Physics Coordinator
J. Carroll, Health Physics Supervisor
Other licensee employees contacted included six technicians, two mechanics,
and four office personnel.
Other Organizations
Radiological Services
Numanco
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NRC Senior Resident Inspector
- W. T. Orders
- Attended exit interview
2. Exit Interview
The inspection scope and findings were summarized on June 5,1986, with
those persons indicated in Paragraph 1 above. One apparent violation for
failure to follow radiological protection procedures was discussed in
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detail. The licensee acknowledged the inspection findings and took no
exceptions.
The licensee did not identify as proprietary any of the materials provided
to or reviewed by the inspector during this inspection.
3. Inspector Followup of Onsite Events (93702)
a. Synopsis of Event
On the morning of Ma, 29, 1986, a contract health physics technician,
who had been performing work in Unit I lower containment, was found to
be contaminated upon exit from the Reactor Building (RB). The
contamination was identified as a single microscopic particle of-mixed
nuclide composition with a total activity of 0.802 microcuries. The
technician was decontaminated by showering and a dose to the skin of
the whole body of 4525 millirem was assigned to the worker.
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b. Review of Exposure Event
Through discussions with licensee representatives, interviews with
involved personnel and review of licensee records, ~the circumstances
surrounding the May 29, 1986, contamination event were examined. On
that date at approximately 0415 hours0.0048 days <br />0.115 hours <br />6.861772e-4 weeks <br />1.579075e-4 months <br />, a vendor health physics (HP)
technician dress'ed out in one pair of cloth coveralls, one pair of
cotton . glove liners, two pair of rubber gloves, two pair of plastic
booties, one pair of rubber overshoes, a particulate respirator, and
two hoods and at 0445 hours0.00515 days <br />0.124 hours <br />7.357804e-4 weeks <br />1.693225e-4 months <br /> entered into Unit 1 lower containment. The
technician was to provide general support for the steam generator, (S/G)
"D" platform crew who were involved in nozzle dam installatfor. work. A
platform had been erected at the S/G "D" manways in upper cotitainment
and entry to the platform was via a ladder, the bottom of which rested
in lower containment. The area surrounding the foot of the ladder had
been roped off as a radiation control zone (RCZ), the floor of which
had been covered with Herculite. The Herculite had been extended to
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form walls about the RCZ of approximately two to three feet in height.
Between 0445 and 0530 hours0.00613 days <br />0.147 hours <br />8.763227e-4 weeks <br />2.01665e-4 months <br />, another HP technician was assigned to
containment. to perform such activities as changing filters on air
samplers, area smears and swabbing air lines that were to be used by
the platform workers to ensure that they were not contaminated. None
of this work required physical entry into the RCZ.
At approximately 0530 hours0.00613 days <br />0.147 hours <br />8.763227e-4 weeks <br />2.01665e-4 months <br />, the platform crew of two workers and a
platform HP technician entered lower containment. The two HP
technicians then present assisted the two workers in donning bubble
hoods and setting up communications after which the platform crew
ascended the ladder to the S/G "D" platform.
At approximately 0615, the first S/G jump was made for purposes of
inspection and measurement preparatory to nozzle dam installation. The
second jump occurred shortly thereafter for the purpose of reaming out
the nozzle dam insert holes. A tool with a rotating wire brush was
used for this activity. Since the licensee required the use of the
" buddy system" for all S/G entries, the first worker remained on the
platform while the second worker was reaming the holes. The platform
HP technician acted as timekeeper. When the second worker exited the
S/G, the first worker descended the ladder to the RCZ below. 4
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At approximately 0645 hours0.00747 days <br />0.179 hours <br />0.00107 weeks <br />2.454225e-4 months <br />, the general area HP technician in lower I
containment donned a disposable coverall and an extra pair of rubber
gloves preparatory to assisting the first platform worker in removing
part of his protective clothing. When the worker came down the ladder,
the HP technician stepped onto the outer edge of the RCZ and helped the
worker remove - his bubble hood and cut him out of his wet suit. The
technician then removed the disposable coverall and extra set of'
gloves.
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Between 0700 and 0815, the general area HP technician continued to
perform radiological surveillance activities in lower containment (air
sampling and smears survey). At 0815, the technician exited
containment and removed all protective clothing at the HP control
point. Upon monitoring, the technician was found to be contaminated on
the inside calf of the right leg. While at the control point, the
technician used tape to try to remove the contamination but was
unsuccessful in doing so. Consequently, disposable coveralls was
donned and the technician was escorted to the " hot" shower by a second
HP technician. An HP Supervisor was also dispatched to the " hot"
shower.
In the shower room, a full body survey of the HP technician was
conducted and three areas of contamination were identified: (1) inside
calf of the right leg which measured 60 millirad / hour, (2) outside of
the right arm just above the elbow which measured 12 millirad / hour and
(3) the rib cage just underneath the armpit which measured 300 counts
per minute (cpm). After the first shower, the body activity had been
reduced to approximately 300 cpm and after a second shower, body
activity had been reduced to less than 150 cpm. Decontamination was
completed by 0855 hours0.0099 days <br />0.238 hours <br />0.00141 weeks <br />3.253275e-4 months <br />.
During the showering process, several towels had been torn into small
pieces to be used as wash cloths. It was on one of these pieces that
the contamination of highest activity was later recovered. The
contaminated area of the towel reading 60 millirad / hour on a R0-2
survey meter, was cut out, placed in a petri dish and sent for gamma
isotopic analysis. The contamination was found to be a single
microscopic particle composed of a variety of radionuclides as follows:
xenon-131 m; xenon-133; cobalt-58; zinc-69 m; silver-108 m;
neptunium-239; iodine-131, 132, 133; zirconium-95; niobium-95;
technetium-99 m; ruthenium-103, 106; cesium-134, 137; barium-140;
cerium-141, 144; and lanthanum-140. The total activity was
0.802 microcuries. The licensee postulated that the particle was a
piece of zircalloy cladding.
The licensee had conducted an investigation to determine how and when
the technician became contaminated. Due to a history of " hot"
particles at the facility, the licensee had initiated an aggressive
program for monitoring laundered protective clothing and felt confident
that the particle had not originated from the protective clothing.
Since particles, primarily cobalt-60 in composition, had been found in
laundered protective clothing previously, the licensee had purchased
and installed a laundry monitor at the facility in February 1986. The
monitor had a row of six plastic scintillation detectors and a conveyor
belt which moved the clothing underneath the detectors. The lower
limit of detection for the top of the clothing was 100 nanocuries of
cobalt-60 and on the bottom of the clothing, 200 nanocuries of
cobalt-60. The monitor was set to alarm at approximately 20 cpm above
background levels of 20-30 cpm. These levels were significantly below
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that of the recovered " hot" particle. The inspector reviewed the
calibration records for the laundry monitor.
The licensee determined that based on previous area surveys and the
nature of the work performed by the technician prior to entry into S/G
"D" RCZ, that no opportunity for exposure to high levels of
contamination had existed. The first work performed by the technician
associated with high levels of contamination was cutting the S/G jumper
from his wet suit which took place at approximately 0700 hours0.0081 days <br />0.194 hours <br />0.00116 weeks <br />2.6635e-4 months <br />. Since
decontamination of the HP technician was complete at 0855 hours0.0099 days <br />0.238 hours <br />0.00141 weeks <br />3.253275e-4 months <br />, the
licensee used an exposure time of one hour and fifty five minutes to
calculate total exposure. Based on the one hour and fifty five minute
stay time, an exposure of 4500 millirad beta and 25 millirad gamma
radiation was estimated to the skin of the whole body distributed over
a one square centimeter area. When added to the previous skin of the
whole body exposure accumulated during the calendar quarter of
315 millirem, a total dose to the skin of the whole body was determined
to be 4,840 millirem.
Examination of the Radiation Work Permit (RWP) records revealed some
confusion as to which RWP was in effect for the HP technician and ,
consequently what the protective clothing requirements were.
Examination of the contaminated individual's dose card for the time of
interest showed that containment entry had been made under RWP No.
86-1162, Unit 1 Reactor Building-Eddy Current Testing S/G "D," while
examination of the RWP time sheets showed that the individual had
signed into the Reactor Building (RB) on RWP 86-1167, "ID" S/G Nozzle
Dam Installation. The Station Health Physicist stated that the
individual should have been signed into the RB on RWP 86-1183,
Miscellaneous Outage Entry into Lower Containment and Pipe Chase. The
distinction of which RWP was applicable to the worker was of importance
since the RWP was the instrument utilized by the station to specify the
radiological requirements for a job.
The licensee confirmed that the use of RWP 86-1162 was an error since
at the time of the inspection eddy current testing had not been
performed on Unit 1 S/G "D." HP personnel stated that RWP 86-1167 was
written for S/G workers who were performing tasks on the platform and
- making entries into the S/G. Since the general HP technician was not
! involved in actual platform work, but remained in lower containment to
perform routine task and to support the jump crew, it appeared that her
work activities were not covered by RWP 86-1167. In addition, the HP
technician was not in compliance with RWP No. 86-1167 which required
the wearing of one cloth coverall and one plastic suit. Since the
licensee indicated that the technician should have used RWP 86-1183,
the protective clothing requirements specified for the RWP were
examined. As RWP 86-1183 was initially written on May 15, 1986, the
technician was in compliance with regard to protective clothing
requirements. However, the Station Health Physicist stated that
RWP 86-1183 had been verbally amended to require that technicians who
cut S/G workers from wet suits don a wet suit themselves prior to any
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cutting. The time and date of this verbal amendment were unknown since
no record had been made, and RWP 86-1183 was not revised to reflect the
new requirements. It was also learned that after contamination
problems had been identified in lower containment after S/G "A" work
early in the week of May 26, 1986, RWP 86-1183 had been again verbally
amended to require all workers entering lower containment to wear two
sets of cloth coveralls and a respirator. The exact time and date of
this verbal amendment was not known since this change, too, was never
documented, but the consensus of the HP staff was that verbal
instructions had been issued prior to the May 29, 1986, contamination
event. The inspector discussed this issue with the HP technician who
had been contaminated. The technician stated that she had been unaware
of the upgrade in protective clothing requirements to the RWP and had
thought that she was in compliance. She further stated that prior to
cutting the S/G worker from his wet suit that she had donned the
disposal coverall and an extra pair of gloves to provide greater
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protection for herself and by doing so though that the protective
clothing she had on exceeded those of the RWP.
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- The Station Health Physicist also stated that after the May 29, 1986,
event, RWP 86-1183 was again verbally amended to require all entries
- into Unit I lower containment to wear, among other items of protective
clothing, one cloth coverall and one plastic suit. This change was
again undocumented so that the exact time and date of the new
requirement was not known. The inspector reviewed RWP 86-1183 at 1330
hours on June 4,1986, and none of the more restrictive radiological
requirements, as specified above, had been documented by a RWP
revision.
Technical Specification (TS) 6.8.1 requires that written procedures be
established, implemented, and maintained covering applicable procedures
recommended in Appendix A of Regulatory Guide 1.33, Revision 2,
February 1978.
Appendix A, Regulatory Guide 1.33, Paragraph 7.e.1 recommends that the
licer.see have radiation protection procedures to control access to
radiation areas including a radiation work permit system.
The inspector reviewed licensee procedures related to the RWP program.
HP Manual, Section 2.1, Radiation Exposure Control, Paragraph 2.1.2.d
stated that all personnel are responsible for following all
instructions and directions presented by HP including adherence to RWP
requirements. Paragraph 2.1.3.3 of the same procedure stated that in
regard to violation of requirements of RWPs, personnel did not have the
prerogative of deciding whether or not to meet one or more of its
requirements and that permission for a temporary deviation from RWP
requirements was required. Further, the deviation from requirements
was to be specified in the Shift HP log. The inspector asked to
examine the Log entry which permitted the HP technician to deviate from ;
the requirements of RWP No. 86-1183. The licensee stated that no such !
Shift Log entry existed in that deviations from RWP requirements were ;
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for the relaxation of radiological requirements of RWPs and were never
intended to apply to situations where protective measures for personnel
had become more restrictive due to changing radiological' conditions.
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Health Physics Manual Section 2.4, Radiation Work Permits, stated that
the RWP was a tool utilized to specify the radiological requirements
for any job on radioactive or contaminated equipment within the
Radiation Control Area of the station. Paragraph 2.4.1 stated-that the
RWP was issued for a particular job in a particular area and on a
specific piece of equipment or on a specific component and that the RWP
contained the specific protective clothing requirements.
Since RWP 86-1183 protection clothing requirements. had been verbally
revised several times prior to the contamination event on May 29, 1986,
discussions were held with licensee representatives concerning
mechanisms in place for control and review of RWP revisions. The
licensee indicated that HP Manual Section 2.4 did not address RWP
revision and that the changes in requirements for RWP 86-1183 had been
promulgated via the various HP supervisors after instructions to do so
by the Station Health Physicist. Although conversations with the
concerned HP Supervisor indicated that the requirements had been
communicated, the HP technician who had become contaminated stated that
she was unaware of the upgrade in radiological requirements for the
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RWP. Consequently, as written on May 15, 1986, and in effect on
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May 29, 1986, neither RWP 86-1167 nor RWP 86-1183 covered the scope of
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the work actually performed by the technician in lower containment,
i.e., cutting S/G workers from their wet suits after S/G entry, and
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therefore neither RWP was applicable to the job being performed by the
l technician. The inspector informed the licensee that failure to
specify appropriate radiological requirements for individuals working
in Unit i lower containment as required by HP Manual Section 2.4 would
be considered an apparent violation of TS 6.8.1 (50-369/86-15-01). At
the time of the exit interview, the Station Health Physicist informed
the inspector that all RWPs dealing with Unit 1 lower containment had -
baen revised to reflect the most current protective ' clothing
requirements.
4. Second Contamination Event
a. Synopsis of Event
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A second contamination event occurred on June 4, 1986. A licensee l
mechanic who had been working in Unit I upper containment was found to l
be contaminated upon exit from the RB. The contamination was
identified as a single microscopic particle of cobalt-60 with a total
activity of 1.96 microcuries. The individual was decontaminated and a
dose to the skin of the whole body of 2180 millirem was assigned the
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b. Review of Event
On June 4, 1986, at approximately 1220 hours0.0141 days <br />0.339 hours <br />0.00202 weeks <br />4.6421e-4 months <br />, the mechanic entered the
HP control point. He proceeded to tne change room where he dressed in
protective clo+hing pursuant to RWP 86-1196, Removal and Replacement of
Unit 1 Reactor Head. Interviews with the individual indicated that he
was dressed in a'cordance
c with RWP requirements. The mechanic entered
Unit I upper containment at approximately 1300 hours0.015 days <br />0.361 hours <br />0.00215 weeks <br />4.9465e-4 months <br /> and between 1300
and 1530 hours0.0177 days <br />0.425 hours <br />0.00253 weeks <br />5.82165e-4 months <br />, he assisted the crew in the reactor cavity by lowering
tools and directing the polar crane. At apprcximately 1630 hours0.0189 days <br />0.453 hours <br />0.0027 weeks <br />6.20215e-4 months <br />, the
individual donned a particulate respirator and descended to the floor
of the reactor cavity to assist in unwrapping sandboxes, square covers
which prevent leakage from the reactor cavity when in place and which
are installed prior to cavity flooding. These covers had been stored
wrapped in three layers of Herculite since the last refueling outage.
This activity was completed at approxiraately 1630 hours0.0189 days <br />0.453 hours <br />0.0027 weeks <br />6.20215e-4 months <br />, at which time
the worker ascended from the cavity to the RCZ at the top. At this
point, the worker removed one outer set of rubber gloves, one pair
rubber overshoes, one pair of plastic booties, one hood and his
respirator. He made his way directly to the hatch exit and removed the
remainder of his protective clothing, one hood, one pair of rubber
gloves, two sets of cloth coveralls, one pair of plastic booties and
one pair of cotton glove liners. When monitoring himself for
contamination using an RM-14, off-scale readings were observed. The
worker donned a disposable coverall and was sent to the " hot" shower.
A whole body survey was performed using a R0-2 ion chamber and an
exposure rate of 176 millirad / hour beta and 1.5 millirad / hour gamma
radiation was measured in the right groin res ion.
The spot or particle of contamination was removed from the worker by a
single wipe of the area with a damp paper towel. Decontamination was
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complete by 1700 hours0.0197 days <br />0.472 hours <br />0.00281 weeks <br />6.4685e-4 months <br />. Isotopic analysis of the material showed the
presence of a single radionuclide, cobalt-60, with a total activity of
1.96 microcuries.
The licensee conducted an investigation of th~ event and determined
that for reasons cited previously, the contamination most probably
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could not have arisen from laundered protective clothing. Based on the
fact that the worker was wearing two sets of cloth coveralls and was
not performing extremely physical work which would have encouraged
heavy sweating, the licensee determined that it was not reasonable to
assume that the cobalt-60 particle could have worked its way through
two sets of coveralls, a pair of modestry shorts and a set of
underwear. Consequently, the time most probable for contamination was
undressing at the RB hatch when the particle could have transferred
from the outer coveralls to the inner coveialls and finally to the
skin. The contamination event was considered to have occurred at the
time the worker removed his protective clothing at 1645 until
decontamination was complete at 1700 or 15 minutes.
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A dose to the skin of the whole body assigned the worker from the
particle was 2170 millirad beta and 10 millirad gamma radiation. For
the second calendar quarter of 1986, the worker had previously received
1005 millirem to the skin of the whole body-which combined with the
t skin dose from the particle gave a dose to the skin of the whole body.
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of 3185 millirem for the quarter.
. The inspector reviewed the licensee investigation report of the event,
surveys of the area, RWP No. 86-1196 and licensee dose calculations.
The licensee stated that in the future, outer coveralls would be
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removed at the RCZ at the top of the reactor cavity prior.to the worker
t exiting the area. The second set of coveralls would be removed at the
j RB exit. i
No violations or deviations were identified.
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