IR 05000213/1987020

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Insp Rept 50-213/87-20 on 870720-24.No Violations Noted. Major Areas Inspected:Preparations for 1987 Outage & Program for Control of Contamination by Radioactive Particles
ML20238D040
Person / Time
Site: Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date: 09/01/1987
From: Shanbaky M, Sherbini S
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20238D031 List:
References
50-213-87-20, NUDOCS 8709100530
Download: ML20238D040 (6)


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U.S. NUCLEAR REGULATORY COMMISSION

REGION I

Report N /87-20 Docket N License No. DPR-61 Priority -- Category C Licensee: Connecticut Yankee Atomic Power Company P. O. Box 270 IIs~rtford, Connecticut 06101 Facility Name: Haddam Neck Nuclear Power Plant Inspection At: Haddam Neck, Connecticut Inspection Conducted: July 20-24, 1987 Inspector: !/!S7 S. Sherbini, Radiat"on Specialist date Approved by: k,L N M. Shanbaky, Chief

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h 9///b7 date l Facilities Radiation Protection Section Inspection Summary: Inspection on July 20-24, 1987 (Report No. 50-213/87-20)

Areas Inspected: Routine, unannounced inspection of the preparations for the 1987 cutage and the program for control of contamination by radioactive particle Results: Within the scope of this inspection, no violations were observed.

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8709100530 870902 gDR ADOCK 05000213 PDR

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DETAILS ,

1.0 Persons Contacted 1.1 Licensee Personnel

  • H. Clow, Supervisor, Health Physics
  • E. Debarba, Superintendent, Station Services R. Groves, Assistant Supervisor, Radiation Protection,  ;

Services

  • D. Miller, Station Superintendent
  • W. Nevlos, Supervisor, Radiation Protection, Operations L. Silvia, Health Physicist
  • M. Sweeney, Supervisor, Radiation Protection, Services A. Vomastek, Assistant Supervisor, Radiation Protection, Operations F. Yelton, Technician. Health Physics, Operations ,
  • Denotes attendance at the exit intervie l 1.2 NRC Personnel J. Shedlosky, Senior Resident Inspector A. Asars,-Resident Inspector 2.0 Access Control During the Outage

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The procedure for control of access into the Radiological Controls Area (RCA) was reviewed. Implementation of 'this procedure was also verified by review of active Radiation Work Permits (RWP) and observation of worker entries into the RCA. The access control process was found to be 4 good, particularly control of access into high radiation areas. The procedure for RWP generation and use has been upgraded prior to the start ,

J of this outage. Access into high radiation areas requires approval of '

radiological controls supervision and completion of a high radiation area access control card. The card contains an updated total of the individual's exposure during the quarter to the time of issue of the card, and also the individual's remaining allowable exposure to his administrative limit. This allows closer control of exposure Health physics technicians preparing RWPs for high radiation area work are provided with a check list of important items that must be reviewed prior to completing the RW The RCA has been divided into zones, as in the previous outag Each one is under the supervision of a health physics technician. This concept has been demonstrated to be effective from experience during the previous outage. A special control point has been established to control access and work in the steam generator area. Each steam generator is monitored by closed circuit TV, and each of the steam generator monitors is manned continuously by a health physics technician. A supervisor at the control point can selectively monitor work in any of the four steam generator area I

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3 4 Observation of activities at the containment entry control point suggest- 5 ed that the control point is prone to becoming congested and disorderl Space is limited and cannot easily accommodate more than a small number of workers seeking access into containment. Also, the number of health physics technicians manning that control point was sometimes not adequate to cope with the work. This work includes checking the worker's authorization to enter containment, ensuring review of the RWP, issue uf dosimetry, and conducting any necessary briefings. The control point is also the exit point from containment, and the exit area also tended at times to become overwhelmed by the numbers of people exiting containmen Barrels staged at the exit area and used to collect the various items of used protective clothing were often observed to be full to overflowin ,

The licensee stated that they were considering several solutions to this problem. However, they stated that the immediate solution will be to increase the number of technicians manning the control point and also to increase the frequency of emptying the barrels containing used protective clothing. The frequency of restocking the change room with laundered protective clothing was also to be increased. The inspector noted that these temporary measures had been implemented before the end of the inspection, and that some of the problems noted had been alleviate Posting of radiation and contamination areas was reviewed and found to be adequate. The zones were clearly identified, and the control point for each zone was clearly visible and accessible. Additional posting was put l out by the ALARA group to identify areas within the RCA that are above average background because of proximity to a source of radiation, and areas that are below average background. These postings were intended to alert' workers to methods of reducing their exposure while working or moving from point to point within the RC Preparations for the outage were found to be substantially better than the previous outage. Major jobs were clearly identified and the exposure goal for each job was set. The job scope and exposure goal setting process had been started during the previous outage and continued until the current outage. Site personnel, including health physics personnel, had a major input during all phases of the outage plannin These

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inputs have apparently had a significant impact on determining the scope of the outage work as well as details of each job. The result of this cooperative effort has been to reduce the exposure estimate from a preliminary 1800 person-rem to the current 827 person-rem. The site ALARA group has published a manual entitled " Pre-outage ALARA Overview" in which the major outage jobs are described. Each job description includes the scope of work, a description of the work area, and a description of the ALARA measures to be implemented. The manual is intended as an information supplement for site management. The health physics department also published a manual entitled " Radiation Protection Awareness".

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The manual is intended to inform workers of various aspects of work in the RCA. This includes a description of RWP use, posting, dosimetry requirements, exposure control cards and high radiation area cards, respiratory., contamination, description of the zones, and other safety and procedural issue .0 Hot Particle Control Program Implementation of a program to control dispersion of and contamination by radioactive, or " hot particles" was incomplete at the time of thi inspection. Some elements of the program, however, were in place. A Hot Particle Control and Accountability Guideline had been prepared by the Health Physics Department. Provisions were made to designate and post any area in which hot particle contamination is found as a " hot particle" area. During preparations for the outage, contaminated areas were cleaned using various methods, including using vacuum cleaners equipped with HEPA filters and rollers with sticky tape attached to the roller to pick up hot particles. The licensee stated that this decontamination effort was quite successful in reducing the extent of contamination in the RC Protective clothing worn in potential hot particle areas will be orange in color and will be segregated in orange bags after use for laundry ,

purposes. Tools and other equipment used in hot particle areas will also undergo special surveys before release. Surveys for contamination in areas with the potential for hot particle contamination are performed using masslin swipes and a pancake probe to scan the massli Two PCM-1.whole body friskers have been installed at the exit point at the main control point to the RCA. Everyone leaving the RCA must pass through these monitors. The monitors are checked daily using slab '

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sources of Cs-137. A tnird PCM-1 monitor has also been installed inside the containment control point, on the containment side. In addition, the i stay time for anyone working in containment has been fixed at a maximum of 90 minutes . At the end of the stay time, the worker must exit containment, remove protective clothing, and pass through the containment whole body frisker. If no contamination is detected, the worker may then put on fresh protective clothing and proceed back into containmen Although the containment whole body frisker is in a much higher back-ground field than is desirable (30,000 cpm compared to 5000 cpm at the main control point), it should nevertheless be capable of identifying the higher activity contaminant I Rules of thumb have been developed for use by technicians to quickly estimate the skin dose when hot particle contamination is found. The I

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rules apply to the pancake probe and the R0-2 survey meter. Based on these rules, 400 cpm on the pancake probe is equivalent to a skin dose rate of 1 mrem /hr. For the R0-2, an open window reading of 1 mR/hr is equivalent to a skin dose of about 125 mrem /hr. These rules have been

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printed on small cards and issued to all the health physics technicians for use in the field. Identification of a contaminant as a hot particle is currently based on the so-called " drop off" method. In this method, the technicians scans the contaminated area and, if the reading drops off quickly, then the contaminant is

.probably a hot particle. The inspector stated that this technique is probably difficult to apply properly. The licensee stated that the technicians have been trained in the method and should be able to apply it in the field. The licensee stated that they will also review other available methods. Accurate skin dose calculations are performed using the computer prngram VARSKIN, based on an isotopic analysis'of the particle on a gamma spectromete At the time of this inspection, the licensee was processing laundry on site using a freon system that was being operated by contractor personnel. The licensee was in the process of discontinuing this operation, however, and will begin sending the laundry offsite to a commercial processor. The site health physicist had visited the processor's facility to ensure adequate capabilities to identify contamination in processed items. Laundry items from hot particle areas will be processed separately. The items will be surveyed twice after washing, once from the outside of the article and a second time with the article turned inside ou At the time of the inspection, the licensee had not developed a method to routinely perform spectroscopic analyses of particles identified during contamination surveys. There was no geometry on the site gsirma spectrometers to allow analysis of hot particle Health Physics had sought the assistance of the Chemistry department to analyze a hot particle identified on a worker prior to the start of this inspection. The method used by Chemistry was to dissolve the particle in acid and place the solution in a 10 ml vial, for which a calibrated geometry was available. Although this method is ,

valid, it is time consuming. This licensee stated that they were reviewing alternative methods to accomplish this analysis. The inspector also pointed out that in the case of hot particles of fuel origin, the gamma spectrometer will not identify pure beta emitting isotopes, such as the isotopes of strontium and yttrium. It is therefore necessary to develop a method to estimate the activities of these isotopes. The licensee stated that the site health physicist will address this problem and establish a suitable metho .0 Nt Particle Contamination Incident A hot particle was found on a contractor crane operator while the opera-tor was frisking in the PCM-1 whole body frisker. The incident occurred E on the afternoon of July 10, 1987. The operator entered the RCA at 1630 and started operating the crane at about 1700. The particle was removed

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with sticky tape at about 1915. He was dressed in one pair of coveralls, rubber gloves and cotton liners, surgeon's cap, and hard hat. The particle was removed from the upper right side of the back. Upon survey with the pancake probe, the meter went offscale. The R0-2 reading was 8 mR/hr. The licensee stated that the operator did not work in any known contaminated areas and only operated the crane during his stay in the RC It is believed that the hot particle was picked up from the protec-tive clothin Based on the rule of thumb for estimating skin dose from R0-2 readings, namely 1 mR/hr corresponding to 125 mrem /hr skin, the dose rate to the skin was about I rem /hr. Assuming that the particle was picked up from the protective clothing, the mar.imum contact time with the skin was 2.75 hours8.680556e-4 days <br />0.0208 hours <br />1.240079e-4 weeks <br />2.85375e-5 months <br />. The skin dose is thus estimated to be atout 3 rem At the time of the incident, there was no calibrated geometry on the gamma spectrometer to measure such particles. The geometry used for smears was therefore used, and it was believed to be a good approxima-tion. This analysis showed 1.54 uCi of Co-60. The licensee used these i analysis results in VARSKIN and calculated a' skin dose of approximately 6.8 rem. The inspector discussed these results with the licensee and it was concluded that the geometry used on the gamma spectrometer may not have been appropriate. The Chemistry department was asked for assistance. They dissolved the particle and used their 10 mi vial calibrated geometry. Based on this method, the activity was determined to be 0.22 uC1. Using this activity, the revised dose calculation yielded a skin dose of approximately 3 rems. This was accepted as the

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more reliable estimate of the dos As a result of this incident, several revisions were made in the hot particle control program, including restriction of stay time in contain-ment to 90 minutes, and the development of an easily used geometry to analyze hot particles on the gamma spectrometer. Checking of protective clothing both inside and outside of the garments for radioactivity at the laundry vendor was also instituted, b.0 Exit Interview The inspector met with licensee personnel at the conclusion of the inspection on July 24, 1987. The scope and findings of the inspection were discussed at that tim E'; .

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