IR 05000213/1986022

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Insp Rept 50-213/86-22 on 860722-25.Violation Noted:Failure to Adequately Control Work in High Radiation Areas During Steam Generator Maint Activities,Which Led to Whole Body Occupational Exposure in Excess of Federal Limits
ML20206P121
Person / Time
Site: Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date: 08/15/1986
From: Lequia D, Shanbaky M, Weadock T
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20206P113 List:
References
50-213-86-22, NUDOCS 8608270102
Download: ML20206P121 (11)


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U.S. NUCLEAR REGULATORY COMMISSION Region I Report N _86-22 Docket N _

License N OPR-61 Priority --

Category C Licensee: Connecticut Yankee Atomic Power Company i

Post Office Box 270 Hartford, Connecticut 06101 Facility Name: Haddam Neck Nuclear Power Plant Inspection At: Haddam Neck, Connecticut Inspection Conducted: July 22-25, 1986 Inspectors: 4/t 8-If-80

. Weadock, pation/S ecialist date D. LeQuia, (griatioVSiec'alist

& 8 -tS- 8 to date

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Approved By: -9V/ N hd/b/

M. ShanbakF, ~ Chief, Facilities Radiation

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date Protection Section Inspection Summary:

Areas Inspected: Routine unannounced inspection of the Radiation Protection Program during steam generator eddy current testing and tube plugging evolutions, including: ALARA, High Radiation Area Control and Radiation Protection Program implementatio Results: Within the scope of this inspection, three violations were identified pertaining to a failure to adequately control work in high radiation areas dur-ing steam generator maintenance activities (see discussion in Section 3.0).

This failure of control led to a whole body occupational exposure in excess of federal regulatory limit e60819 '

PDR ADOCK 05000213 G PDR

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DETAILS 1.0 Persons Contacted During the course of this inspection, the following personnel were con-tacted or interviewed:

1.1 Licensee Personnel J. Ferguson, Unit Superintendent

  • G. Bouchard, Station Services Superintendent
  • J. LaPlatney, Assistant to Station Superintendent
  • J. Ashburner, Supervisor - Betterment and Construction H. Clow, Health Physics Supervisor
  • W. Nevelos, Radiation Protection Supervisor
  • R. Brown, Operations Supervisor
  • W. Bartron, Maintenance Supervisor 1.2 NRC Personnel
  • S. Pindale, Resident Inspector
  • M. Shanbaky, Chief, Facilities Radiation Protection Sectio Other licensee or contractor personnel were also contacted or inter-viewed during this inspectio * Attended exit meeting on July 25, 1986.

2.0 Purpose

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The purpose of this inspection was to review and evaluate the licensee's radiation protection activities during a mini-outage for steam generator eddy current testing and tube plugging operations. This evaluation, which started as a reutine inspection, became reactive in nature following the identification of an occupational radiation exposure of one worker in excess of the regulatory limits of 10 CFR 20.101(b). The following elements are included in the evaluation:

  • Radiation Protection I'mplementation/0verexposure Incident
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3.0 Overexposure Incident On July 23, 1986, the licensee communicated to NRC representatives on-site that an apparent whole body radiation exposure to one worker in excess of federal limits had occurred during steam generator (S/G) work activitie The involved worker (Worker A) was performing work to support hyorostatic testing of S/G #4 from approximately 3:00 am to 5:30 am on July 23, 198 Worker A's activities included the performance of multiple " half-Jumps" (insertion of the head, arms and chest) into S/G #4 for camera reposition-ing. The apparent overexposure was discovered when the worker's pocket ionization chamber (PIC) was read after the completion of work activitie Worker A's high range PIC, positioned on the head during work, indicated an exposure of 1700 millirems. This exposure, when added to the worker's previous exposure for the quarter (1620 millirem), indicated an exposure (3320 millirem) in excess of allowable limits (3000 millfrem/ quarter).

The licensee immediately processed worker A's TLD badge, also positioned on the workers head, to determine the dose received. The TLD badge is the licensee's official dosimeter for records. The badge indicated an exposure of 1672 millirem, which, when added to the previous quarterly exposure, indicated an exposure in excess of regulatory limits (3292 millirem).

NRC investigation into the events leading to the overexposure included the following activities:

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D.iscussion with involved personne Discussion with Health Physics supervisory personne Tours and observation of ongoing work activities at the S/G worksit Review of the following documentation:

  • S/G worker " jump sheets" and exposure records.

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Procedure ACP 1.0-4, " Radiation Work Permit Completion and Flow Control".

  • Training and qualification records for involved personne Based on the above review, three apparent violations were identified. A description of the events leading to the overexposure is given belo .1 Event Description Steam generator work activities on July 23, 1986 included. tube marking in S/G #2 and hydrostatic testing of S/G #4. HealthPhysics(HP)

staffing to support work activities included two senior HP technicians and an HP clerk. One senior technician was stationed at the control

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point desk outside the loop bioshield area. This individual's respon-sibilities included monitoring S/G work via closed circuit TV, time-l keeping for S/G workers to track and control expohure, and maintaining

communications via headsets with the S/G workers. The second senior
HP technician and the HP clerk were available to control the dressing I and undressing of S/G workers, and to periodically read the workers l

PIC to monitor his exposure.

! Workers performing S/G maintenance requiring insertion of their body l 1 into the S/G channel head were required by the controlling RWPs to i wear the following dosimetry: thermoluminescent dosimeters (TLDs)

on the chest, hesd, and hands. Along with each TLD, a worker wore a l pocket ianization chamber (PIC), which provides on the spot estimates ;

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of exposure.. Workers performing jump activities wore plastic suits l and bubble hoods for respiratory protection purposes. Since the bubble ;

hood prevented easy access to the PIC on the workers head, the tech-

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nicians placed " sacrificial" PICS on the outside of the hoods to allow i easy reading. This " sacrificial" PIC was not required by the RW horker A began work on S/G #4 at approximately 0300. He had already i

received 1620 millf rem of exposure during this quarter and was conse-

] quently authorized to receive an additional 880 millirem before the

station administrative quarterly limit of 2500 millirem was reache !

He performed two half-jumps into the channel head (20,000-30,000 mR/hr)

{ and continued working on the S/G platform (250-1000 mR/hr) until approximately 0450, at which tirre he.was called out of the area by l the HP technician to have his PIC read. At this point, it was noted '

that the " sacrificial" PIC located outside the bubble hood was missin j The two senior HP technicians conferred and agreed to allow worker A

! to return to the S/G platform and resume work activities. The senior

! technicians evaluation which lead to this decision was based on the ,

technicians knowledge of previous work activity: earlier that shift, ;

Jl a worker had performed what was thought to be similar work on S/G #4 *

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and only received 850 millirem in three and one quarter hours.

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sWorker A returned to work and completed his work activities by approx-

! Imately 0530. During this period, he made two additional half-jumps

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into the S/G. Upon removal of his bubble hood, the two PICS on his ,

head (one low range 0-1500, one high range 0-5000) were read. The low range PIC was found to be offscale; the high range PIC showed an

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exposure of 1700 millirem. At this point, station personnel recognized an apparent overexposure had occurred and worker A's TL0s were sent

, for processing. Results from the whole body TLD located on worker

A's head showed 1672 millirem, which, when added to exposure received previously in the quarter, gives a total quarterly exposure of 3292

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10 CFR 20.101(b)(1) requires that "during any calendar quarter, the j total occupational dose to the whole body shall not exceed 3 rems".

l Failure to restrict worker A's quarterly exposure to less than 3 rem

(3000 millirem) is an apparent violation of 10 CFR 20.101(b)(1).

l (213/86-22-01)

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3.2 Causal Factors t

l Subsequent NRC review of the above events identified the following j apparent direct causes of the overexposure.

' The Hp technicians failed to appropriately monitor and control worker A's exposure during the work activity. Procedure ACP 1.0-4, " Radiation Work Permit Completion and Flow' Control," Step ;

i 5.6.1.6, requires, in part, that "... direct surveillance of '

j workers by a Health Physics technician will be required in those

instances where high dose rates, extreme changes in radiation f
levels, or other radiological hazards preclude workers from
independently monitoring and minimizing their exposure."

l j Failure.of the HP technicians to read worker A's Plc during the i S/G work activity constitutes an apparent violation of Procedure

! ACP 1.0- (213/86-22-02).

i The inspector determined from: (1) worker A's stay times in the l high radiation areas, and (2) licensee dose rate measurements, I

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that worker A's exposure at 0430 was approximately 700-800 mre This additional exposure would have brought him near his admin-l 1strative quarterly whole body limit of 2500 mrem.

$ The HD technician's decision to allow worker A to return to work

} based on another worker's (worker 8) stay time and exposure was i unreasonable since a subsequent interview of worker B indicated

! that: 1) he had not made any whole body entries to the S/G, and j 11) had retreated to a lower dose area off the S/G platform when- ,

ever he was not required to be there. 10 CFR 20.201(a) defines

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a " survey" as an evaluation of the radiatton hazards -incident to

] the production, use, release, disposal or presence of radioactive j materials. 10 CFR 20.201(b) requires that each licensee make

such surveys as necessary to comply with all sections of Part j

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! The use of an inappropriate evaluation of radiation hazards and l radiological conditions in extending the workers stay time con- '

1 stitutes an apparent violation of 10 CFR 20.201(b) in that an l adequate survey (evaluation) was not performed. (213/86-22-03)

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3.3 Contributing Factors NRC investigation of the above incident also identified several problems with the radiological control of the S/G work activit Al+. hough these problems do not appear to be directly related to the overexposure, they may be contributing factors and are deserving of note and specific attention by tFe license . Worker A was originally directed to perform tube marking activ-ities on S/G #2; he consequently initialled and checked into containment on RWP #864038 for S/G #2. Once inside containment, worker A was directed by Westingh6use super /ision to support the hydrostatic testing of S/G #4; no change to the RWP sign-in sheets was made and worker A did not initial RWP #864040 "S/G #4 Tube Plugging Project" to indicate he had read i Procedure ACP 1.0-4, " Radiation Work Permit Completion and Flow Control", Step 5.5.2, requires in part that ".. . workers are responsible for initialling the RWP ... acknowledging they have read and under-stand the RWP...". Failure of worker A to initial the sign-in sheet for RWP #864040, which he subsequently worked, constitutes an apparent violation of ACP 1.0-4,(213/86-22-02). The inspec-tor compared the two RWPs and determined that reauired radiolog-ical controls were identical. Questioning of worker A indicated that he had been appropriately briefed as to the dose rates ard conditions for S/G #4, rather than S/G #2. The above failure to sign-in on the correct RWP therefore did not act as a causal factor for the subsequent ovarexposur . Interviews of other workers performing S/G work indicated that, even when available, PICS were not always read by the HP tech-nicians. One worker indicated his PIC was not read once during a three-hour work period on a S/G platfor . Several workers indicated that the cable bookups to the headphones worn by the workers were too short and may have restricted their ability to move to a lower dose rate are .4 Licensee Corrective Actions

On the afternoon of July 23, 1986, the licensee interviewed the indi-viduals involved in the overexposure incident, including: Health Physics, supervisory and worker personnel. From these interviews, they concluded that a failure to comply with company procedures and policies did exist in relationship to the overexposure of one of the ,

steam generator workers. Based on their findings, the licensee allowed work to recommence with the following additional controls implemented to prevent reoccurrence: ,

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7 The licensee reemphasized that job supervision and the HP Tech-nicians assigned S/G responsibilities will have a prejob discuss-ion including upcoming job scope and goals to be achieved prior to entering containmen . Platform workers will be issued a Dositec with an alarm setpoint 200 mR below the available quarterly licensee's administrative limi These workers will-be instructed to exit the loops area if the alarm setpoint is reached and report to the S/G control poin If the worker leaves the skirt prior to the alarm, a HP technician will monitor the PIC reading prior to allowing the worker back onto the platfor . While in the S/G skirt, workers will be instructed to minimize time spent on the upper platform in the area of the manway . When multiple entries are required to the upper platform or channel head, the waiting between entries will be done in lower dose rate areas outside the skirt. Back-up jumpers will wait in the bullpen, not in the skir . Any questiorable PIC readings will terminate all activities associated with the affected S/G until HP supervision has reviewed the situatio . A dedicated HP work group will be supplied for each S/ . High Radiation Authorization Cards will be issued for one RW Entry on subsequent PWPs will require additional High Radiation Authorization Card During subsequent tours of the containment butiding and steam generator work area, the inspectors observed that these additional steps appeared to provide sufficient control for the work in progres .0 ALARA The licensee's program for maintaining and ensuring that doses to workers remain "As low As Is Reasonably Achievable" (ALARA) was reviewed against criteria in:

Regulatory Guide 8.8, "Information Relevant to Ensuring that Occupa-tional' Radiation Exposures at Nuclear Power Stations Will Be As Low As Is Reasonably Achievable"

Regulatory Guide 8.10 " Operating Philosophy for Maintaining Occupa-tional Radiation Exposures As Low As Is Reasonably Achievable"

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The licensee's performance relative to the above criteria was determined by:

Review of the steam generator primary side tube plugging job exposure summar *

Interview with the ALARA Coordinato * Review of personnel exposure record *

Review of radiation survey results performed in support of steam generator repair activitie *

Review of the Plant Design Change Request (PDCR #839) and its accom-panying Design ALARA checklist for steam generator tube pluggin *

Review of 1986 station exposure goals vs. current exposure statu Within the scope of this review, no violations were identified. However, some strengths and significant weaknesses in the ALARA program were note ' hey are discussed in the following tex .

The licensee is continuing in their efforts to improve the ALARA progra Conseqtently, a significant monetary incentive increase was recently proposed and accepted raising the dollars / man-rem from $1000/ man-rem to

$20,000/ man-re This substantial increase, one of the highest in the

' industry, should help to justify the capital costs associated with procure-ment of the equipment and/or processes necessary to reduce dose rates, and, thereby, bring a turnaround in the escalating exposure at the plan Review of the current 1986 exoosure status identified that over 1616 man-rem have beep expended thus far, with an additional 135 man-rem budgeted for the steam generator mini-outage. This will bring station exposure to approximately 1750 man-rem for the year; well above the man-rem exposure associated with a typical pressurized water reacto It appears, however, that the licensee's good intent in the ALARA area is weakened at the point of implementation.~ This is evidenced by their ,

staging of workers on the steam generator (S/G) manway platforms or skirt areas, which are high radiation areas, for extended periods of time during S/G maintenance activities. In addition, low dose rate working areas for -

this activity were not effectively establishe These poor practices may have contributed to an exposure of a worker in excess of federal limits as discussed in Section 3.0 of this repor Further investigation of the ALARA program identified a continuing tendency to submit Plant Design Change Requests (PDCR) to the ALARA group with insufficient time to orovide effective exposure reduction input for the job. During discussions with the ALARA Coordinator, he stated that PDCR

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  1. 839, which concerned S/G. tube plugging, was not submitted for review until July 19,1985, with work commencing on July 20, 1986. He stated that this

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was an insufficient amount of time for a proper review. Additional dis-cussions with the ALARA Coordinator appeared to indicate a lack of ALARA group involvement and oversight of on going work activity to ensure that all ALARA provisions have been complied with, or if additional measures are necessary. This lack of oversight may have contributed to the over-exposure incident, as workers stated that they felt that the communication lines for S/G work were too short to allow them to move to low dose rate area .0 High Radiation Area Control The licensee's program for the control of high radiation areas was reviewed against criteria contained in:

  • 10 CFR 20, Standards for Protection Against Radiatio *

Technical Specification 6.13, "High Radiation Area".

The licensee's performance relative to the above requirements was determined by:

Review of Radiation Work Permits for work in support of steam generator n.ai ntenanc * Review of survey record *

Independent surveys performed by the inspecto *

Tours of the reactor containment buildin *

Observation of health physics procedure implementation and utilization at the work sit * Inspection of locked high radiation areas in the reactor containment buildin *

Review of Radiation Protection Procedure 6.2-8, " External Radiation Exposure Control and Dosimetry Issue".

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Review of Administrhtive Procedure 1.1-92, "High Radiation A.rea Key Issue".

Review of Radiation Protection Procedure 6.1-7, " Posting of Radio-logical Control Areas".

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Within the scope of this review, no violations were noted. However, two apparent weaknesses were observed, concerning: (1) control of tne locked high radiation area that provided access to #2 and #3 steam generator; and (2) monitoring requirements for entry to high radiation areas. These items are discussed belo .1 On July 23, 1986, while making a tour of the containment building, the inspector observed a locked high radiation area (LHRA) gate propped open. This gate allows access to the loop areas of the plant. A health physics (HP) technician was observed sitting just outside this gate. The inmector asked the technician if he could enter the area as part of his tour. The technician stated he was not assigned as a gate watch. (Radiological Protection Procedure RAP 6.1-7, specifically requires that areas with '... dose rates greater than 1000 mrem / hour shall have all entrances locked or shall be continuously guarded to prevent unauthorized entry..."). The inspe.: tor proceeded to the lower containment HP checkpoi.nt to verify entry and control requirement After being assured by checkpoint personnel that the HP technician was indeed stationed to guard the gate, and that entry to the area as equipped was possible, the inspector returned to the gate and entered the area. While in the LHRA, the inspector observed the HP technician leave the gate area and proceed into the loop areas to assist a S/G worker out of his plastic sui This effectively left the gate un-guarded. During subsequent discussions with licensee personnel at the checkpoint, they stated that the gate is observed on a television monitor when it is left unattended. However, the inspector noted that the individual placed to observe the bank of four monitor screens would have difficulty in providing positive control of each entry to this LHRA, because the individual indicated that his prima responsi-bilities were timekeeping and control of S/G channel head entrie These responsibilities required constant attention and appeared to preclude effective control of the monitor for the gate area. This issue was discussed with licensee management, who suspended contain-ment work activities at noon on July 23, 1986, to investigate this incident, the overexposure incident (see Section 3.0) and high radia-tion area entry concerns raised by the inspector. After recommencing work in containment, the inspector again toured the area and noted that effective health physics controls had been established to control access to locked high radiation' area ~

5.2 During entries into the containnient, and subsequent tours of the S/G maintenance area, the inspector observed personnel entry into 00sted high radiation areas. Technical Specifications require that an indi-vidual or group of individuals permitted to enter such areas shall be provided with one or more of the following:

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11 Use of a continuously indicating dose rate instruent; Use of an integrating dose device which alarms at a preset value; or, Use of an individual establishing positive controls and equipped with a dose rate dev' ice who performs periodic radiation surveil-lance at the frequency specified in the RW The inspector observed personnel entering containment and one steam generator worker exiting the loop areas, both of which are posted and controlled as high radiation areas (HRA), without the use of a dose rate' instrument or integrating dose device (options ~one er two).

During subsequent discussions with the licensee, they indicated that option three was being exercised. An apparent weakness exists when the licensee uses option three. In tr.is situation, workers are sent into posted HRAs equipped only with a thermoluminescent dostmeter and a pocket ion chamber (PIC) and not accompanied by, or positively con-trolled by, a person qualified in HP, who performs periodic radiation surveillance. The licensee was relying on routine surveys rather than pe-iodic radiation surveillance at a frequency specified in a Radiation Work Permit (RWP). The Technical Specification requirement for periodic s~urveys is further defined ~by the licensee in Procedure ACP 1.0-4, as'" intermittent". The term periodic, as it applies to radiation surveillance, needs to be clearly understood by the HP technician covering the job; either by verbal briefings, procedural direction or RWP requirement. In addition, the frequency of periodic surveillance must be consistent with_the radiological hazards asso-ciated with the activity. The licensee's practice of allowing per-sonnel to enter posted HRAs under option three without accompaniment by a health physics qualified individual equipped with a dose rate monitoring device, does not meet the requirements of Technical Spec-i fication 6.13.1.C. However, a violation will not be issued at this time, since licensee surveys, and independent surveys performed by the inspector, verified that the individuals had not entered any high radiation fields above 100 mrem /hr. The Technical Specification requirement to provide periodic radiation surveillance was discussed with licensee management, who stated that access to, surveillance and control of work activities in High Radiation Areas will be examined and upgraded as necessary'. The inspector stated that this area will be reexamined during a future inspection ~

6.0 Exit Meeting The inspectors met with licensee management denoted in Section 1.0 on July 25, 1986 at the conclusion of the inspection. The scope and findings of the inspection were discussed at that tim