ML21019A266
| ML21019A266 | |
| Person / Time | |
|---|---|
| Site: | 07007004 |
| Issue date: | 02/23/2021 |
| From: | Wiehle K American Centrifuge Operating |
| To: | Jean Trefethen NRC/NMSS/DREFS/ERMB |
| Trefethen J | |
| Shared Package | |
| ML21019A270 | List: |
| References | |
| Download: ML21019A266 (1) | |
Text
From: Wiehle, Kelly L To: Trefethen, Jean Cc: Faraz, Yawar; Coflin, Monika
Subject:
[External_Sender] NRC Clarifications Requested -- Environmental Report Date: Wednesday, January 06, 2021 5:18:01 PM
- Jean, One of your questions centered around what our anticipated calculated doses or maximum values for the exposed individual/worker would be during our extended 10-year continued operation of those same 16-centrifuges since we will continue to increase the material stored in our process building.
Based on historical data from the gaseous diffusion plant and Lead Cascade operations, we do not expect any person to exceed 500 mrem/yr. Monitored individuals dose data is evaluated as needed to ensure doses stay below the 500 mrem per year administrative limit. This is accomplished with robust Survey, Radiation Work Permits (RWPs), and As Low As Reasonably Achievable Committee (ALARA) programs. Routine and job specific surveys identify elevated radiation areas and are tracked and trended to detect changes in conditions or the gradual buildup of radioactive material. This is supplemented by fixed area dosimetry. The Radiation Work Permits identify the need for supplementary dosimetry including self-reading dosimeters or electronic dosimetry. Supplementary dosimetry would be required for entry into a High Radiation Area (HRA). However, an HRA is a remote possibility. Alarm levels are set for both dose rate and total integrated dose as necessary. Dose margins are generally set at 80% of administrative limits (500 mrem). The ALARA program uses the data from the survey program, personnel dosimetry, and supplementary dosimetry. Individual doses can be tracked via spreadsheets on a daily basis if needed. The ALARA Committee reviews jobs that have higher individual or collective dose concerns. While not anticipated, the ALARA Committee can authorize levels above the 500 mrem per year individual administrative limit.
While an ALARA principle is to keep all individual levels low, this is not to be at the expense of a relatively larger collective dose. This may be the case when only a few individuals have the experience performing complicated tasks.
Please let me know if you need further clarifications or a discussion with the Radiation Protection folks providing this response.
Kelly