05000335/FIN-2011002-01
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Finding | |
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| Title | Failure to perform adequate surveys to identify potential radiological hazards during valve repair in the 1B WGDT room |
| Description | A self-revealing non-cited violation (NCV) of 10 CFR Part 20.1501(a) was identified for failure to perform adequate surveys to verify radiological conditions within the Unit 1 B Waste Gas Decay Tank (WGDT) room prior to allowing workers to enter the area. This resulted in workers unknowingly entering an area with general area dose rates exceeding High Radiation Area (HRA) conditions, i.e., dose rates exceeding 100 millirem per hour (mrem/hr) at 30 centimeters (cm). Because of the potential for changing radiological conditions resulting from normal operation, radiation protection staff established controls for access to all WGDT rooms through administrative postings and locked entry doors to ensure monitoring and establishment of appropriate radiological controls prior to worker entry into the areas. However, on October 4, 2010, two maintenance workers were allowed access to the 1B WGDT room without a Radiation Protection Technician (RPT) performing a survey prior to entry. One worker subsequently received a dose rate alarm on their Electronic Dosimeter (ED), maximum dose rate measurement of 77.5 mrem/hr which exceeded the ED dose rate alarm setpoint of 75 mrem/hr. Both workers exited the room and contacted the assigned RPT. Subsequent surveys measured HRA conditions adjacent to the 1B WGDT, maximum general area dose rates of 250 mrem/hr, resulting from operations venting gas to the subject tank several hours before the workers entered the room. Room postings and access controls were upgraded immediately for the identified HRA conditions. The licensee entered the issue into their corrective action program (CAP) as condition report (CR) number AR 585076. This finding is greater than minor because it was associated with the Occupational Radiation Safety Cornerstone attribute of Program and Process (Monitoring and RP Controls) and adversely affects the cornerstone objective of ensuring adequate protection of worker health and safety from exposure to radiation from radioactive material during routine civilian nuclear reactor operation. The finding was evaluated using the Occupational Radiation Safety Significance Determination Process (SDP) and was determined to be of very low safety significance (Green) because it was not related to As Low As Reasonably Achievable (ALARA) Planning and the ability to assess dose was not compromised. In addition, it did not involve overexposure or substantial potential for overexposure because the maximum exposure rate within the 1B WGDT were not estimated to exceed Locked High Radiation Area (LHRA) conditions, WGDT room doors are administratively locked, keys only issued to RP personnel, and the entrances are posted Radiation Area, Contact RP Prior to Entry. The cause of this finding was directly related to the cross-cutting aspect of Conservative Assumptions in the Decision Making component of the Human Performance area because the RPT assumed that radiological conditions in the 1B WGDT room had not changed, even though additional administrative controls were in place due specifically to the identified potential for changing radiological conditions in the area when venting gas to the WGDT. H.1(b). |
| Site: | Saint Lucie  |
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| Report | IR 05000335/2011002 Section 2RS1 |
| Date counted | Mar 31, 2011 (2011Q1) |
| Type: | NCV: Green |
| cornerstone | Or Safety |
| Identified by: | Self-revealing |
| Inspection Procedure: | IP 71124.01 |
| Inspectors (proximate) | S Ninh D Rich R Patterson B Collins J Beavers R Kellner S Mendez-Gonzalez J Rivera-Ortiz W Loo G Kuzo T Hoeg M Speck S Sanchez |
| CCA | H.14, Conservative Bias |
| INPO aspect | DM.2 |
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Finding - Saint Lucie - IR 05000335/2011002 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Saint Lucie) @ 2011Q1
Self-Identified List (Saint Lucie)
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