IR 05000309/1990011
| ML20043H484 | |
| Person / Time | |
|---|---|
| Site: | Maine Yankee |
| Issue date: | 06/20/1990 |
| From: | Nimitz R, Pasciak W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20043H482 | List: |
| References | |
| 50-309-90-11, NUDOCS 9006260007 | |
| Preceding documents: |
|
| Download: ML20043H484 (24) | |
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U.S. NUCLEAR REGULATORY COMMISSION l
REGION I
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Report No.
50-309/90-11 Docket No.
50-309 License No.
DPR-36 Priority Category C
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Licensee:
Maine Yankee Atomic Power Company 53 Edison Drive Augusta, Maine 04336 i
facility Name:
Maine Yankee Atomic Power Station inspection At:
Wiscasset, Maine Inspection Conducted:
June 5 7, 1990 Inspector:
O.L dung 6 2.6)90 R. L. Nimitz, CHP, Senior Radiation Specialist Cl ate'
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Approved by:
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nAt m 6 80-90 W. J. Tasciak, chief, f acilities Radiation date Protegtion Section Inspection Summary:
Inspection conducted on June, 5-7, 1990 (Inspection Report No. 50-3U9790 ll)
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Areas Inspected: The inspection was a special, announced Radiological Controls Inspection to review the circumstances, the licensee's evaluations and the
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licensee's corrective actions associated with an unplanned exposure of three I
contractor workers.
The three workers were involved in the repair of the elevation of the Primary Auxiliary Building)(body) during the primary component cooling system valve (PCC No. PCC-A-216 located on the 11'
PAB 1990. The workers sustained unplanned whole exposures of 500 millirem, 655 millirem and 1200 millirem respectively.
Results:
Four apparent violations were identified during the inspection:
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Failure to make radiation surveys as required b compliance with 10 CFR 20 Details Section 8.2;y 10 CFR 20.201 to ensureFailure to perf surveillance of a High Radiation Area as required by Technical Specification 5.12, Details Section 8.2; Failure to instruct radiation workers in precautions or procedures to minimize their exposure as required by 10 CFR 19.12, Details Section 8.3.1; Failure to follow radiation protection procedures as required by Technical Specification 5.11, Details Section 8.4.
9006260007 900620
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PDR ADOCK 03000309 i,-
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DETAILS 1.0 Individuals Contacted 1.1 Maine Yankee Atomic Power Company E. T. Boulette Vice President Operations
- R. Blackmore, klant Manager
- R. Nelson, Manager, Technical Support
- G. PillsburyActing Radiological Controls Section Head Radiation Protection Manager
- J. Connell,
- W. Hayward, QA Supervisor
- D. Whittier, Manager, Nuclear Engineering and Licensing 1.2 NRC
- R. Fruedenberger, Resident Inspector, Maine Yankee 1.3 Others
- P. Dostie, State Nuclear Safety Inspector, State of Maine
- Denotes that the above individuals attended the exit meeting on June 11, 1990.
The inspector -1so contacted other licensee personnel during the course of this inspectio;..
2.0 Purpose and Scope of Inspection The inspection was a special, announced Radiological Controls Inspection to review the circumstances the licensee's evaluations and the licensee's corrective actions assoclated with the unplanned exposure of three contractor workers.
The workers performed repair work on primary component coolant (PCC) system valve No. PCC A-216 located on the 11'
elevation of the primary auxiliary building (PAB) during the period May 7-17, 1990.
The three workers received estimated unplanned radiation exposures to the whole body of 500 millirem (mrem), 655 mrem and 1200 mrem respectively.
3.0 Licensee Action on Previous Findings unplan)ned radiation exposure event that resulted in a worker receivin0 an (0 pen Unresolved Item. (50 309/88 22-01) The NRC will review an apparent 3.1 apparent whole bod The licensee was unable to clearly *le/ quarterly dose of 2800 millirem.
xplain the dose assessment for this a) parent unplanned exposure event.
he inspector indicated that this was tie second attempt by the NRC to review this matter and that additional licensee effort was needed to ensure that a clear dose assessment was completeo for NRC review,
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(Closed Unresolved Item (50 309/90 09 01) NRC to review the reactor coolant) viewing portals to determine if they provide a potential 3.2 unauthorized access point into the loop areas, a locked High Radiation Area. The licensee provided additional information in a letter to the NRC dated May 16, 1990. The letter indicated that the portals were not normal access points, that personnel could possibly enter into the loop areas via these portals and that entry by this means could result in potential injury to personnel. The licensee s ex)lanation appeared reasonable. The licensee secured each portal wit 1 a metal bar.
The portals e ra secured on June 2, 1990.
This matter is closed.
(Closed Unresolved item (50-309/90 09 02 NRC to review the licensee's High Rad)iation Area control practices to d)etermine if operators escorted 3.3 millwrightsandALARAtechniciansintolockedH19h Radiation Areas in violation of approved procedures. The inspector s review of radiation work permits for the period in question (April 16anddiscussionswithcognizantpersonnelindIcate 1990, through May 2, 1990 individuals into locked High Radiation Areas.
The inspector noted that the licensee's High Radiation Area access control procedure was revised on May 2,ble and would conform with Technical 1990 to allow this practice practice was considered accepta Specification requirements. The inspector did note that the licensee issued a Radiation Protection Night Order on April 16, 1990, which condoned this practice.
The inspector indicated that issuing Night Orders which are inconsistent with procedure requirements was considered a poor practice. This matter is closed.
4.0 bckground 4.1 Individual'sConcerns(RI-90A-00651 On May 29 1990 an individual contacted the NRC's Region I office. The individualstaledthatcontractorworkershadworkedonavalve located on the lower elevation of the Primary Auxiliary Butidino(PCC A 216)
T The workers had unlino(wing)ly PAB and had received unplanned radiation exposures.
lain across a grating on the floor that exhibited radiation fields of 150 milliRoentgens per hour (mR/hr). The workers believed they had been working.in a 30 mR/hr radiation field.
4.2 NRC. Action and Scope of Review On May 30, 1990, the individual was contacted by a Senior Radiation Specialist from the NRC's Region I office. The individual discussed the nature and sco)e of his concern. On June 7, 1990, the NRC dispatched an inspector to tie Maine Yankee Power Station to review the circumstances surrounding the unplanned exposures.
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The individual's concerns and the adequacy of the li ensee's controls for the valve repair activity were evaluated by the following means:
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The inspector entered the area where tFe unplanned exposure had
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occurred and made independent radiation intensity measurements.
'I The inspector interviewed workers who had worked in the area including
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workers who had received unplanned exposures and job supervisors.
j The ins >ector interviewed radiation protection personnel including
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those w1o had provided job coverage for the valve repair work and those involved in generation of radiation work permits.
The inspector performed inde)endent verification of the unplanned
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radiation dose received by tie workers.
The inspector interviewed other licensee personnel including dosimetry
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personnel and training personnel.
l 5.0 circunc+ances Surrounding the Unplanned Exposure The licensee issued Discrepancy Report No. 2310 90 on May 7 1990, to correct an apparent 3roblem involving failure of valve PCC k-216 to completely close. Tie lack of complete closure prevented 10 CFR 50 AppendixJtestin9ofcontainmentpenetrations81Aand818. Thevalveis
located on the 11 elevation of the Primary Auxiliary Building (to thePAB) and is located in a locked High Radiation Area. The work was assigned licensee's valve repair contractor.
Special Radiah Work Permit (SRWP)trols for the disassembly and repairwas issue No. 90-1144 7, 1990, to prov d radiological con of the valve seats. A radiation survey dated May 4, 1990, was used to obtain radiological conditions for the work area (See Figure 1).
The survey, actually obtained to support replacement of air filters on valve actuators, indicated general area radiation dose rates of between 30 50 i
milliRoentgens per hour (mR/hr)inute per 100 centimeters squared with contamination levels of between 1000-2000 disintegrations per m
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(dpnV100cm2. The SRWP indicated that the work would take about 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and that wor)kers would sustain an aggregate radiation exposure of 0.350 person rem.
The person-rem exposure estimate and radiological controls provided on the radiation work permit were based on radiological conditions in the immediate vicinity of the valve. The licensee's radiation protection technician, who issued the radiation work permit was unaware that work
would be performed by the workers while they lay,on their backs on the l
floor under valve PCC A-216. The postions that the workers would be placing their bodies in relative to the valve were not discussed.
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'l The SRWP required that a High Radiation Area door watch be present and that radiation )rotection technicians would provide technician coverage every 60 minutes, ladiation and contamination surveys were to be performed prior to work start.
Prior to May 12 1990 the area was controlled by lock and key. After May 12, 1990, clo,sedcIrcuittelevisionwasaddedto continuously monitor the access point from the radiation protection check
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point.
Initial work started on the disassembly and re> air of valve PCC A 216 at
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8:38 p.m. on May 7, 1990 7-17,199b,andcontinuedthrougitoMaythe licensee's radiation protecti 17, 1990. During the period May providing job coverage gave pre job briefings at the beginning of the start
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of each new shift for tie workers working on the valve.
The radiation protection technicians also performed SRWP survey verifications at the
start of each new shift. These once a shift surveys involved entering the i
areas to check that the dose rates identified on pre work surveys had not
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changed.
Four contractor workers C D on the internals of the v(Workers A, B,he,re) performed the majority of work i
alve during t During the valve work,in trench that was(Workers A,ith a meta) pair activity.
several workers B, and C had l' in under the valve across a dra covered w l grat.ns The workers were unaware that the drain trench exhibitec c(See Figure 2.D.
ontact radiation exposure dose rates of 150 180 mR/hr.
This resulted in the workers' lower
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back and thigh areas being in about a 150 mR/hr field while the pocket dosimeter worn on the front chest indicated an ap>arent dose rate,hibited based on
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l rate of accumulation, of about 30 mr/hr.
The wor (ers were not pro l
trench was of concern. grating nor did they believe that lying across the from lying across the Discussions with the radiation protection personnel who had issued the L
radiation work permit for the valve repair indicated that they had not addressed what the full scope of work would be including the various positions of the worker; bodies when performing the work.
There was no
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apparent Work Party Leader for this valve repair activity.
However, on at least two occasions, radiation protection technicians, covering the valve repair activity, questioned the valve repair workers as to where they would be working. The technicians were informed by the workers questioned that they would be working on top of the valve. However, these discussions did not cover all shifts or all workers.
During the period May 7-17,1990,hift,indicatedthattheradiafionfieldsperformed the SRWP verification surveys prior to the start of work each s
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and contaminction levels were consistent with the radiation survey used to
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generate the SRWF. The radiation protection technicians did not routinely enter the area to perform radiation surveys while work was on-going. As a result, workers were et observed lying on their backs with the lower portion of their body across the grating. One worker estimated he had worked on his back for at least 10.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />. The radiation protection personnel periodically checked the workers' pocket dosimeter readings by y3111ag to the wrkers from outside the krea. (See Figure 3., LO0dit6n c)
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(Note: The periodic checking of pocket dosimeter readings by the radiation protection technicians covering the valve repair is not supported by worker readingswerecheckedveryinfrequentlyifatall.)pocketdosimeter statements.
The workers' statements indicate that The licensee experienced trouble repairing the valve during the period May 7 11 1990 Several attempts to repair the valve had occurred but the leak testIngres.ults were not considered satisfactory. As a result the licensee assigned an individual to directly oversee the repair, operation.
be performed by two workers (Wor'ars A and B) on the night ',"k activity to In addition, on May 12, 1990, the contractor assigned the wo hift.
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OnMay14,dosethanthatreceivedbyhiscoworkersbutattributeditto i
1990 Worker B noted that he appeared to be receiving more radia; ion his working periodically in closer proximity to a 70,000 mR/hr hot spot i
near the work location.
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On May 15, 1990 Worker B worked on valve PCC A 216 between 4:40 a.m and 5:30 a.m., when an operator entered the vicinty of the work locatioa and commenced venting and draining liquid from the discharge line off tie quench tank throuch valve PR 42. This operation took about 10 minutis with the operator remaining in the actual area of the venting and draining for l
about 5 minutes. The operator performed a radiation survey of the drain valve and trench before and after the draining.
The araining took about 3 minutes with about 3-5 gallons of liquid bein
drained to the trench. This liquid flowed toward the worker who was ly ng
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i on or next to the trench. The drain valve indicated about 1000 mR/hr w ile the trench indicated about 150 mR/hr.
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The o>erator noted the worker lying in the area of the trench and informed him t1at no problems were apparent. Although the operator's radiation work permit indicated that a respirator was requirad to be worn in the area of the venting and draining, no respirator was w>rn. Also, an airborne radioactivity sample was to be collected when the system was opened and
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during venting and draining.
Although the operator indicated he collected a " drop gas" sample, no air sample results were available to support that a sample was collected.
The valve worker lying rear the trench did not have a respirator.
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Because the workers believed they were receiving more exposure than r,9cessary during their repair of PCC-A-216 the workers requested on hcy
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16, 1990, that additional shielding be installed to reduce dose rates in the work area. -The request was reviewed by the licensee's ALARA coordinator who concluded on May 17,1990, at 9:00 a.m. that additional shielding was not needed.
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(Note: On May 16 1990 at 9:26 a.m. the licensee's published RWP summary report indicated { hat the valve re air was at 1450.83% of the man-hour estimate (116 hours0.00134 days <br />0.0322 hours <br />1.917989e-4 weeks <br />4.4138e-5 months <br /> versus 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and 411.43% of the exposure estimate (1.44 man rem versus 0.350 man rem. This information was not evaluated by the ALARA coordinator.)
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At about 7:35 p.m. on May 17, 1990, two of the licensee's valve contractors (Worker A and Worker B informed the radiation protection technicians providing High Radiatio)n Area and job coverage for the PCC A-216 work,,that they wisied to work on the valve. A radiation protection technician was dispatched to the area to perform the normal SRWP survey verification and open up the t 3 for the workers.
The radiation protection technician entered the locked area (See Figure 3 Area gate). while Worker A and Worker B waited at the locked High Radiation attached.
The workers observed through the gate that the technician performed a radiation survey of th(e incorrect valve).
When the radiation protection technician returned to the gate to let the workers in, the workers informed the technician that he had surveyed the wrong valve.
The workers )ointed out the correct valve and requested that the technician survey tie correct valve.
The technician stated that the area in question was normally between 20 30 mR/hr.
Since the radiation protectica technician had removed his protective clothing and could not at that time re enter the area (a contamination radia)fionsurveymetertoverifythedoseratesintheworkarea.the workers requested that the te area The i
technician provided the meter to the workers who surveyed the work area and
noted an area where they had lain (on the grating over the trench) to read offscale on the 50 mR/hr scale of the survey meter. When the workers i
switched the meter to the 100 mR/hr scale, the workers observed erratic
readings.
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The workers informed the radiation protection technician of the results and I
indicated that the 100 mR/hr scale was not working and that this area must be checked out. The workers contacted the backshift contractor ALARA technician and informed him that the area they had iain in was over 100
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mR/hr and that they apparently were only receiving about 20 30 mR/hr based on pocket dosimeter results. The pocket dosimeters and thermoluminescent dosimetry (TLD) badges were located on the chest while the highest exposure dose rate was being delivered to the lower back areas of the body.
The contractor ALARA technician entered the area and performed a survey of the work area and noted u) to about 180 mR/hr on contact with the grating in the area where the wor (ers had lain.
The contractor ALARA technician informed the workers that they could work in the area but that they must lie next to (parallel) to the trench instead of across it.
The workers lay parallel to the trenc(Workers A and Bj returned to work on the valve but h.
The workers si permit at about 11:45 p.m. on May 17, 1990.gned out on the radiation work I
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The contractor ALARA technician informed the contractor valve supervisor and the PAB radiation protection supervisor of the radiation fields emanating from the trench. The contractor A1 ARA technician determined that the workers may have received unmonitored radiation exposure and subsequently pulled the dosimetry of the four workers (Workers A, B C, and D) at or
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about 11:00 p.m. on May 17, 1990.
The contractor ALARA technician performed a dose estimate for the four workers on May 17 1990 and the morning of May 18, 1990 and concluded that the four workers Workers A, B, C and D may have received unplanned unmonitoredradiaionexposuresof1917m) rem,1211arem,774mremand,518 mres, respectively. The licensee ini tiated an investigation of the unplanned, unmonitored radiation exporures on May 18, 1990.
6.0 Licensee Review, Evaluation and Corrective Actions 6.1 Immediate Corrective Actions The licensee took the following immediate corrective actions upon becoming l
aware of the unplanned, unmonitored radiation exposures of the four workers.
The corrective actions were documented in the licensee's incident report (90 05):
Work was stopped on PCC A-216.
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The dosimetry for the workers was pulled and processed.
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The work area including the trench area was resurveyed.
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Personnel were interviewed concerning the event.
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from a phantom and an estimate of the workers' time in the area.
The event was reviewed by experienced radiation protection personnel
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providing assistance to the licensee.
I The unplanned, unmonitored exposure event was not required to be reported l
but the licensee notified the NRC resident inspector on May 23, 1990.
6.2 Long Term Corrective Actions
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The licensee documented long term corrective actions in the radiological
incident report for the exposure event. TN licensee took or initiated the following long term corrective actions:
The event was discussed at shift turnover meetings and included in
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night orders on May 23, 1990.
The Radiological Incident Report for the event will be forwarded to
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the licensee's training group for inclusion in future training.
The licensee will revise Radiation Protection Procedure 9.1.1, Plant
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Radiological Surveys, by September 15, hen pe,rforming RWP surveys.to in 1990 floor trenchs adjacent to work areas w
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Lead valve workers will be meter trained during the next outage to
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allow them to be more aware of work area dose rates and to better control their exposure. The licensee will evaluate, by December 31
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1990, the types and amounts of survey meters needed to support self, surveys by valve workers.
The licensee will evaluate the value of having technicians dedicated
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to valve work. This evaluation will be performed by June 15, 1991.
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Workers were briefed by their supervisors concerning good
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communications to ensure radiation protection personnel understand job scope and process.
The licensee's management was briefed on the event.
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The licensee proposed developing a standard check list to ensure that
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job scope, protection personnel receive an accurate description of the radiation component location and description as to how the job
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would be performed. Thechecklistwaspro)osedtoincludea requirement that if the job scope changed tsen radiation protection personnel must be notified to reassess the job and perform a walkdown with the worker at the job site.
The licensee proposed that the operations department should evaluate
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the need for generic guidance for draining of systems.
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The inspector noted that the licensee issued a radiological incident report for the unplanned, unmonitored exposure event.
The report identified areas of concern associated with the unplanned,'unmonitored exposure and )rovided resolution of the concerns.
The licensee s report concluded that tie root cause of the event was inadequate communication between workers and i
radiological controls technicians. The report was approved by the plant manager on June 5, 1990.
7.0 Dose Assessment
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7.1 Assessment Results (Licensee)
The licensee completed a dose assessment for the individuals who were t
identified as working under the valve PCC-A 216 during the period May 7-17,
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1990, and who may have received unplanned, unmonitored radiation exposure.
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The licensee evaluated the dose by the following means:
l The licensee interviewed the workers and estimated the amount of time
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they were working under the valve with the potential to have their lower body across the grating.
The licensee performed detailed radiation surveys of the work area to
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obtain gamma radiation dose rates, beta radiation dose rates, and hot particle exposure measurements.
The licensee mocked up a water filled phantom and placed TLDs on the
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li phantom to obtain best estimate radiation dose rates emanating from the grating. The results were compared against ion chamber
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measurements.
The results were comparable and the licensee selected a best estimate dose rate of 150 mR/hr to the lower back portion of the body.
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The licensee concluded that the following dose assessment was a ppropriate:
Table 1 Dose Assessment Results (millires whole body)
Worker Unplanned Dose Received Quarterly Dose Yearly Dose A
B 1205 C
500 2111 2492 655 1288 1746 0 (No unalanned exposure. Did not work under the valve layin 1340 1741 grating.)
er the The licensee's dose assessment indicated no unplanned beta dose received and no exposure to hot particles had occurred.
was 7.2 NRC Evaluation Of Dose Assessment The inspector reviewed the adequacy and methodology of the lice assessment for the workers rkers to verify that aThe inspector also reviewed the licen ee's exposure records for the wo.
hand.
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The inspector concluded that the licensee'ppropriate records were on s
i generally reasonable exposure estimates for the three workers (Wo s me;hodology provided and C Approp)riate records were on hand and no apparent when the dose rate value selected by the licensee is used rs A, B matters were identified: excess of NRC limits appeared to have occurred.
sure in However, the following The licensee's method used a general are.
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results indicated a value of 154 mR/hr.
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rate of 150 mR/hr. TLD at least one worker receiving an additional 4i..nillirem, uld result in Th o m rease co the dose rates that the workers had lain in varied in addition, 180 mR approp/hr.
riate. (See Figure 4.)It is unclear that the value selected (150 mR/h r to The licensee's method did not appear to account for exposure t
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received to the lower portion of the workers' body independent o estimated unplanned was reductio unmonitored exposure.
workers.n of exposur,e actually received by the lower body of theThis to the potential for additional ex)osure of one worke
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had lain on the floor as contaminated li relative operators venting and draining of PR 42. quid flowed by h(Worker B) who im during the relative to the potential intake of airborne radioactivity of worke including the operator were provided.
In addition no conclusions
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three workers (Workers AThe licensee's dose assessments did
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worked under the valve. posure were the only individuals to h e
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The licensee concluded that the following dose assessment was appropriate:
Table 1 Dose Assessment Results (millirem whole body)
Worker Unplanned Dose Received Quarterly Dose Yearly Dose A
1205 2111 2492 B
500 1288 1746 C
655
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1340 1741 D (No unplanned exposure. Did not work under the valve laying over the grating.)
l The licensee's dose assessment indicated no unplanned beta dose was
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l received and no exposure to hot particles had occurred.
7.2 NRC Evaluation Of Dose Assessment The inspector reviewed the adequacy and methodology of the licensee's dose assessment for the workers. The inspector also reviewed the licensee's
exposure records for the workers to verify that appropriate records were on hand. The inspector concluded that the licensee's methodology provided generally reasonable exposure estimates for the three workers (Workers A, B and C when the dose rate value selected by the licensee is used.-
Approp)riate records were on hand and no apparent personnel exposure in excess of NRC limits appeared to have occurred.
However, the following matters were identified:
The licensee's method used a general area dose rate of 150 mR/hr. TLD
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results indicated a value of 154 mR/hr. This increase could result in at least one worker receiving an additional 42 millirem, in addition, the dose rates that the workers had lain in varied from 120 mR/hr to 180 mR/hr.
It is unclear that the value selected (150 mR/hr) is appropriate. (See Figure 4.)
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The licensee's method did not appear to account for exposure that was
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received to the lower portion of the workers' body independent of the estimated unplanned, unmonitored exposure.
This could result in a reduction of exposure actually received by the lower body of the workers.
The licensee's dose estimates did not provide any conclusions relative
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had lain on the floor as contaminated liquid flowed by h(Worker B) who to the potential for additional exposure of one worker im during the operators venting and draining of PR 42.
In addition no conclusions relative to the potential intake of airborne radioactivity of workers, including the operator were provided.
The licensee's dose assessments did not clearly indicate that the
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three workers (Workers A, B and C) who were assigned the unplanned, unmonitored radiation ex worked under the valve. posure were the only individuals to have
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Other valve repair operations had previously occurred near the trenchs
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on the ll' elevation of the PAB. No conclusions relative to potential exposures to workers similar to those repairing PCC-A 216 were included in the licensee's incident report.
The above matters are considered unresolved (50 309/90-11-05)
8.0 NRC Evaluation of Radiological Controls
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8.1 General The inspector reviewed the circumstances surrounding the event,ive actions the licensee's evaluations of the event and the licensee's correct associated with the event.
Thefollowingmatterswerereviewed
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radiological surveys to plan for and support the work
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radiological training and qualifications of workers performing the
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valve repair.
radiological training and qualification of radiation protection
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personnelprovidingkobcoverage radiation work perni s
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arocedures
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.iigh Radiation Area controls
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ALARA planning and oversight of valve repair
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8.2 Exposure Control (NRC Findings)
Within the scope of this review, the following matters were identified:
10 CFR 20,201 Surveys, requires in section (b) that each licensee
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make or cause,to be made such surveys as (1)his aart, and (2) are may be necessary for the licensee to comply with the regulations in t L
reasonable under the circumstances to evaluate tie extent of radiation j
hazards that may be present.
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of the ra(diation hazards incident to the production, use, release,aj of 10 CFR Section disposal or presence of radioactive materials or other sources of radiation under a specific set of conditions. When appropriate, such E
evaluation includes a physical survey of the location of materials and equipment, and measurements of levels of radiation or concentrations
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of radioactive material present.
The inspector's review indicated the licensee was required to make or cause to be made reasonable surveys to ensure compliance with 10 CFR 20.101.
10 CFR 20.101 provides occupational radiation exposure limits for workers.
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l The inspector further noted that 10 CFR 20.202 Personnel Monitoring, i
personnel monitoring (eq)uipment to and shall require the use of s requires in Section a i
,
-
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l equipment by each individual who enters a restricted area under such cfrcumstances that he receives or is likely to receive a dose in any calendarquarterinexcessof25%ofthe.applicablevaluespecifiedin paragra>h (a)lue in 10 CFR 20.101 (a) was 325 millires (i.e. 25% ofThe in of 10 CFR 20.101.
,
l-app 1 Tea >1e va the whole body value).
'
The inspector concluded that the surveys performed by the licensee to plan for and control work on PCC A 216 were inadequate for the i
following reasons:
1.) The licensee did not make radiation measurements in all locations
were the workers positioned their bodies while working on the PCC-A-216 valve. The radiation surveys used to develop the radiation work permit for the repair of the valve during the period May 7 17 1990, only depicted radiation levels at the valve. TheradIationsurveysusedtogeneratetheradiationwork
'
i permit provided whole body dose rates which were a factor of three lower (150 mR/hr versus 50 mR/hr) than those encountered by
,
the workers. (See Figures 2. and 4,)
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2.) The radiation surveys that the radiation protection technicians
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made during the period May 7-17, 1990, to support on going work
'
of the PCC-A 216 valve were inadequate in that they failed to identify the radiation fields on the grating.
The radiation fields emanating from radioactive material in the trench under the gra, ting, measured up to 180 mr/hr.
3.) On the evening of May 17 1990 atabout9:00p.m.ingPCCA216 a contractor
ALARAtechnicianwasinfo,rmedthatworkers repair mayhavebeenunknowinglyexposedtoradiafionfieldsinexcess o
l work on /hr. however t.1e individuals were permitted to return to of 100mR
valve PCC-A 216 without first determining their total whole body dose and their remaining quarterly Kiation exposure
,
value.
j 4.) The licensee's surveys failed to ensuri compliance with 10 CFR 20.202 in that appropriate personnel monitoring equipment was not provided to the workers working on valve PCC-A-216 during the period May 7-17, 1990 in order to monitor the whole bodies radiation ex)osure that the lower portion of their whole bodies received. T1e three workers received radiation exposures to the.
lower portions of their whole bodies in excess of 25% of the applicable value in 10 CFR 20.101.
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13 As a result of Items 1.) and 2.)R/hr during repair of valve PCC A416above, three work a radiation field of about 150 m during the period May 7-17, 1990 and the three workers received unplanned unmonitored exposures of about 1205 millirem, 500 millirem and 655 millirem, respectively to the lower portions of their bodies.
I As a result of item 3.) above, two of the workers (Workers A and B)
were permitted to re-enter radiation fields without a complete understanding of their radiation exposure status. As a result of Item 4.) the three workers unknowingly received radiation exposures to the
'
lower portions of their bodies of about three times that indicated by the personnel monitoring equipment worn on the chest.
,
The inspector concluded that it was necessary and reasonable for the licensee to make or cause to be made surveys to ensure compliance with the requirements of 10 CFR 20.101 and 10 CFR 20.202. These surveys included the physical measurements of radiation fields in the area and evaluation of the workers' total quarterly exposure prior allowing the workers to return to work in a radiation field. The inspector concluded that failure to make or cause to be made such surveys as are
,
necessary and reasonable to comply with 10 CFR 20.101 and 10 CFR
20.202 was an apparent violation of 10 CFR 20.201. (50 309/90-11-01)
Technical Specification 5.12, High Radiation Area, states in Section
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5.12.1 that in lieu of the control device or alarm signal required by paragraph 20.203 (c)(2) ion is at such levels that a major portion ofof 10CFR 20, each the intensity of radiat the body could receive in any one hour a dose in excess of 100 millirem shall be barricaded and cons)icuously posted as a High Radiation Area and entrance thereto siall be controlled by requiring issuance of a radiation work permit'. Any individual or group of individuals permitted to enter such areas shall be provided with or accompanied by one or more of the following:
A radiation monitoring device which continuously indicates the
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radiation dose rate in the area.
A radiation monitoring davice which continuously integrates the -
i
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radiation dose rate in the area and alarms when a preset
integrated dose is received.
Entry into such areas with this
conitoring device may be made after the dose rate levels in the i
area have been established and personnel have been made
knowledgeable of them.
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A radiological controls qualified individual (i.e., qualified in
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radiation protection procedures) with a radiation dose rate monitoring device who is responsible for providing positive control over the activities within the area and who will perform periodic radiation surveillance at a frequency specified in the RWP.
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The inspector's review of the radiological controls provided for the workers working on RWP No.90-Il44 for repair of the PCC-A-216 valve indicated the workers worked in radiation fields of about 150 mR/hr
,
while lying on the grating while working on the valve, 120 mR/hr at l
12 inches from the crating and general area dose rates at waist. level j
of 100-140 mR/hr. The workers' did not have a continuously indicating dose rate meter or integrating alarming dosimeter.
The RWP specified, in Section IV, High Radiation Area Controis-Technical Specification 5.12 th minutes.atradiationprotectioncoveragewastobeperformedevery60 The inspector noted that the job coverage technicians entered the work area only at the start of each shift and oerformed surveillance of the physical radiation surveis were made of what the
!
workarea(i.e.levedwastheapparentworklocation)andthatthe technicians bel i
technicians only checked pocket dosimeter readings once per hour
.
otherwise.
This involved yelling to the workers from well out of the J
work area and asking the workers what their dosimeters read.
Since the pocket dosimeters were worn on the chest, this practice did not i
provide for identification and surveillance of the high radiation t
i fields to which the lower portions of the workers' bodies were exposed.
'
The inspector indicated that failure to perform radiation surveillance at a frequency specified on the RWP is an apparent violation of Technical Specification 5.12.1. (50-309/90-11-02)
'
The inspector also noted that the area was not conspicuously posted in that the High Radiation Area that the workers' were in was not identified on survey maps and was not posted. The entire 11'
elevation of the PAB was posted as a High Radiation Area.
<
The ins >ector further noted that the licensee's RWP procedure states that jo) coverage technicians must verify work area dose rates.
'
The inspector's discussions with contractor radiation protection technicians indicated confusion as to what constitutes coverage.
Radiation protection technicians, dings of what constitutes coverage.providing L
repair, had inconsistent understan The inspector noted that the licensee's radiological incident report had identified this as a concern but that the matter was resolved during a supervisor's briefing.
As of June 11 1990 the inspector's review indicated that the licenseecontinuedtoconsidercheckingofpocketdosimeterreadings
'
as an acceptable surveillance for meeting Technical Specification 5.12.1 surveillance requirements. The inspector indicated that as evidenced by the unplanned, unmonitored exposure of the three workers repairing valve PCC-A-216, reading of pocket dosimeters during on-going work was not adequate under all situations to identify
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radiological problems.
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i The Technical Specifications indicate that this surveillance is to be
)
perforwed by an individual qualifir ' in radiation protection procedures with a radiation dose rate monitoring device.
The inspector indicated that physical surveillance must be performed of the areas at a frequency commensurate with the radiological safety significance of the work sctivity and the radiological conditions in the work area to conform with Technical Specification 5.12.1.c.
The licensee immediately notified appropriate personnel of the need to perform appropriate surveillance of personnel working in High-Radiation Areas where Technical S High Radiation Area Surveillance.pecification 5.12.1.c. is used for 8.3 Training and qualifications (NRC Findings)
,
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8.3.1 Workers The inspector reviewed the adequacy and extent of training and qualification provided to the three workers (Workers A, B and C) who had received unplanned, unmonitored radiation exposures dLring repair of valve PCC-A-216.
{
10 CFR 19.12. Instructions to Workers, states in part that all
!
individuals working in or frequenting any portion of a restricted area
-
shall be kept informed of the storage transfer, or use of radioactive
'
materials or radiation in such portions of the restricted area and in
'
precautions or procedures to minimize exposure.
The inspector's review indicated that the workers, king in a restricted area on valve PCC A 216 on the 11' eleva,1on of the primary auxiliar buildin duringtheberiodMay7-17toI0mR/hremanatingfromradioactiv 1990, were not informed of radiafion fiel$s of u)
contamination in a trenci covered by a grating in their work area.
The workers had lain across the gratin to their work location (See Figure 2).g which was in close proximity As a result, the workers were l
unable to minimize their radiation exposure caused by the radioactive material in the trench.
The inspector noted that the licensee had not surveyed the trench for this work activity and was not aware of the high radiation dose rates emanating from the material contained in the trench and therefore did not instruct the workers in the presence of the high radiation fields.
This was apparently due to the radiation technicians' beliefs that the workers would work in the immediate vicinity of the valve.
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The ins >ector noted however that there was not a clear understanding as to w14t the actual job scope was for this work activity. The inspector also noted that the workers were not instructed to remain and work in the immediate vicini+y of the valve. The inspectar workers? had the need to work away from the valve then radiatio (the further noted that the workers were not informed that if they n
protect 1on personnel must be contacted in order that additional radiation measurements could be performed to fully characterize the new radiological conditions to which the workers would or could be exposed.
The inspector indicated that failure to instruct the workers in precautions to minimize their exposure, was an apparent viciation of 10 CFR 19.12. (50-309/90-11-03)
The inspector's review indicated that the workers were considered by the licensee's training group to be experienced workers and thus did not need to go through the licensee's full general employee radiation training program. The workers received a site specific slide show, were shown a one-half hour radiation protection refresher tape, were were instructed in given the normal general employee training handoutcurrent radiation events, were clothing training and were shown a tape on the radiation work permit system.
The inspector's review indicated no discussions were held during training as to what constitutes " work scope", what constitues a change in work scope or what a worker must do if he changes work scope.
The workers were provided radiation work pemit briefings which were read to'the workers. The briefings indicated that workers were to leave the work area and report to the area radiation protection technician or health physics check point if work scope changes occur that could affect radiological conditions.
Since the work scope was not clear to the workers, lying across the grating was not considered a change in " work scope".
,
8.3.2 Radiation Protection Personnel The inspector reviewed the qualifications of members of the Radiation Protection Group providing radiological controls for the work activity. The inspector contacted other nuclear stations, as appropriate, to verify experience presented in resumes.
The inspector's review indicated the personnel were trained and qualified in accordance with the licensee's program. No apparent violations were identified.
The licensee verified previous experience of contractor radiation protection technicians and provided procedure training.
The following matters were discussed with the licensee:
I
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Specification experience requirements. acquired while manning a control point, A toward Technical I
experience to be credited to meet Technical Specification
experience requirements was considered inappropriate.
The inspector verified that individuals did meet qualification
.
requirements when only a limited portion of the. control point
'
experience was applied toward experience requirements.
The licensee's experience verification work sheet allows for
.
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education to be credited toward Technical Specification
'
experience requirements.
The Technical Specifications do not allow this for technicians. The inspector verified that-
!
technicians met experience requirements when experience for
'
education was subtracted.
Theins!ector'sreviewofradiationworkpermit(RWP) survey
-
verific tion data sheets indicated a junior technician performed
!
RWP survey verifications for RWP No.90-Il44 on May 6, 1990. The
!
coverage surveys. The licensee's Tecinical Specifications '
j inspector noted that the individual a>parently was performina job provide for use of appropriately qualified technicians.
The use l
of junior technicians to perform job coverage surveys does not i
appear to be appropriate. The inspector verified that no work
'
occurred following the surveys until they were re-performed the following day by a fully qualified senior level technician.
The licensee indicated the above matters would be reviewed.
8.4 Procedures-l The inspector reviewed the licensee's implementation of various radiation protection procedures established by the licensee to control radiological work activities.
!
i The licensee's Technical Specification 5.11.1,l radiation protection be Radiation Protection
Program, requires that procedures for personne prepared consistent with the requirements of 10 CFR 20 and be a maintained and adhered to for all operations involving personne$provedradiafion
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exposure.
The-following apparent examples of failure to adhere to radiation protec. tion procedures were identified:
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Radiation Protection Procedure No. 9.1.10, Revision 26, Radiation Work j
Permits states in Section 6.1 that radiological controls personnel will pro, vide the following RWP,information to complete Section II of-the permit:
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"6.1.1 Survey data shall be entered under Initial Survey Measurements:
a. General area dose rates of all areas personnel will enter.
Surveys shall be posted with RWP.
b. Work area dose rates. Surveys shall be posted with RWP."
The inspector's review indicated that the radiation survey used for generating the RWP Section II did not reflect general areas of all areas workers repaIrinavalvekCC-A-216wouldenterduringtheperiod
May 7-17, 1990, and did not reflect all work-area dose rates. The
..
,
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radiation survey a,e to comphte Section II of RWP No. 90-1144, used.
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for repair of valve PCC-A-216 indicated general area dose rates of 30-50 mR/hr. The-surveys did not depict a trench containing radioactive mater 41 that emanated radiation field of up to 180 mR/hr.
The workers unknowingly lay across the trench during the period May
'
7-17, 1990, 2.)
Radiation Protection Procedure 9.1.10, Revision 26, states in Section 6.3 " Job coverage technicians must verify work area dose rates, check i
pocketdosimeterreadings,checkradioactivematerialcontainerdose rates, maintain radiological barricades, and enforce RWP control
"
-measures.
The inspector's review indicated that the job coverage technicians providing job cov g a e for RWP No. 90-1144 for repair of PCC-A-216
'
during the period Ma 7-17, 1990 did not adequately verify work area dose rates. Thetecniciansfailedtoidentifyagratingreadingu
.
l to 180 mR/hr that workers were lying across during the period..In p-
'
addition, tne job coverage technicians failed to enforce the RWP work scope as they understood it in that workers lay on the floor under the valve across-a grating reading up to 180 mR/hr. The work scope, according to job coverage technician written statements did not include lying on the floor.-
3.) Radiation Protection Procedure No. 9.1.10, Revision 26, states in Section 6.1.8 that stay times shall be specified under Section V (of the RWP).
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The inspector's review of Section V of RWP No.90-1144 used for repair of valve PCC-A-216, indicated the permit did not include stay times.
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4.) Radiation Protection' Procedure No. 9.1.10, Revision 26, states in.
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"Section 6.7.1 that-workers must read un radiationworkpermitexactlyaswritfen.derstand-andcomplywiththe RadiatIonworkpermitNo.
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90-1206, Vent and Drain Penetrations In the Letdown Area st a respirator is required if in area of venting and draining.ated that In
addition, the radiation work permit (90-1206) stated that an air
"
suple was required during opening or a system and while venting and draining.
The inspector's review of the operator's draining of valve PR-42, located in the letdown area, on May 15 1990 during the period.
4:40a.m.to5:30a.m.,indicatedthatthe. ope,ratordidnotweara
!
i respirator when in the area of the venting and draining.
The operator
spent' at:least 5 minutes in the area uncapping the vent and drain
'
lines, performing radiation measurements-of the trench in which the
-
liquid was released directly under the drain line, and recapping the vent and drain line.
The entire draining operation was completed in 10 minutes. The operator was not in the immediate area of the venting
'
and draining the other 5 minutes.
The licensee was not able to provide a air sample analysis results documenting the results of the drop gas sample apparently taken by the operator.
In addition to the above workers were repairing valve PCC-A-216 during the venting and dr,aining.
Although the workers were in close
"
proximity to the venting and draining, they were not provided I
respirators, m
a 5,) Radiation Protection Procedure No. 9.1.10, Revision 26 states in Section 6.1.6 that, dosimetry requirements shall. be enfered under Section 111 Iof the RWPf and that multiple dosimetry is required whenever varying radiation fields could result in significantly
,
different radiation doses to several parts of the whole body.
'
The inspector's review of the radiation fields associated with work on the PCC-A-216 valve during the period May 7-17 1990 indicated workers worked in a varying radiation field of,about,30 mR/hr to 150 mR/hr and that such radiation fields could result in significantly
-
different radiation doses to several parts of the whole body and multiple dosimetry was required.
During portions of the work, workers' lower bodies received about four times-the radiation exposure of that indicated by dosimetry worn on the workers' chests.
One if worker's lcwer body sustained an estimated radiation exposure of 1205 millirem while the dosimetry worn on the chest indicated 370 millirem.
'
The above five examples of failure to adhere to radiation protection p(50-309/90-11 -04). roe.edures constitute an apparent violation of Technica
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9.0 Exit Meeting The inspector met with licensee representatives denoted in Section 1 of this report on June 7, 1990. The inspector-sumarized the purpose, scope
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and findings of the inspection.
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