There is no requirement for having you environmental TLDs processed by a NVLAP accredited facility. However, there are RegGuides out there for QA programs involved with environmental laboratories. Your processor may fall into this.
There is a DRAFT ANSI N13.29, American National Standard for Dosimetry - Environmental Dosimetry Performance - Criteria for Testing.
Some questions to ask yourself
They give people a warm fuzzy that your plant is not showing a measurable impact on the environment.
Matt Williamson
Indian Point Unit 3
Williamson.m@nypa.gov
914-736-8416
Not reviewed by anyone