North Anna's response is similar to San Onofre. In addition, we utilize our waste stream analysis to calculate scaling factors to supplement bioassay gamma emitters, isotopic smear results, and air sample results.
Barbara J. Thompson Supervisor of Exposure Control Dominion - North Anna Power Station Email: [email protected] Phone: 540-894-2605 Beeper: #3469 FAX: 540-894-2408 From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Thursday, September 30, 2010 7:03 PM To: [email protected] Cc: [email protected]; [email protected] Subject: Re: Powernet: In Vivo and In Vitro Counting Protocols Greg, As background, INPO recommends internal dose assessment at about the same level that external dose is monitored (10 mrem). EPRI Alpha guidelines recommends the alpha component be included in an dose assessment if an intake is likely to exceed 10 mrem CEDE. The EPRI guidelines describe whole body counting for gamma emitters and scaling factors for non-gamma emitters as the most accurate method of internal dose assessment. Scaling factors are normally based on the ratio of cobalt-58/60 and gross alpha activity from a representative air sample. A representative smear may be substituted if an appropriate air samples is not available. The EPRI guideline recommends that bioassay be considered if an intake is likely to exceed 5% ALI (250 mrem CEDE). It's expected that sampling containers be available and that a contract for sample analysis be in place. It is very unlikely that the 5% ALI level be reached. When establishing a station practice for sampling at a lower level, the negative impact of sample collection on a radiation worker and family should be considered. Since these events rare, each is handled on a case-by-case basis by the radiation safety technical staff. In one case at San Onofre, 24 hour urine was collected. Best regard, Mike To: "[email protected]" <[email protected]> From: "GOWDY, GREGORY M" <[email protected]> Sent by: [email protected] Date: 09/22/2010 06:54PM Subject: Powernet: In Vivo and In Vitro Counting Protocols 1. V. C. Summer would like to know what kind of in vivo counting protocols your nuclear plant has when you have workers with significant (>10 mrem beta/gamma + alpha) measured internal doses. 2. Do you follow a set counting frequency every time so that the counts can be done by HP Techs without input from a Staff Health Physicist or other qualified technically-qualified individual? 3. If you ever experience significant alpha intakes at your nuclear plant that require you to perform in vitro bioassay (fecal and urine sampling), do you follow a set collection protocol for each sample type that is set up for being run by HP Techs without Staff HP or other technically-qualified individual input? 4. Do you have separate protocols for fecal sampling and urine sampling? 5. If you use urine sampling for in vitro, do you specify 24-hr urine or spot urine? CONFIDENTIALITY NOTICE: This electronic message contains information which may be legally confidential and or privileged and does not in any case represent a firm ENERGY COMMODITY bid or offer relating thereto which binds the sender without an additional express written confirmation to that effect. The information is intended solely for the individual or entity named above and access by anyone else is unauthorized. If you are not the intended recipient, any disclosure, copying, distribution, or use of the contents of this information is prohibited and may be unlawful. If you have received this electronic transmission in error, please reply immediately to the sender that you have received the message in error, and delete it. Thank you.
