milk is a primary pathway by which radioactive materials released
into the atmosphere may reach the offsite population. Milk
samples are collected at areas close to the INL Site boundary and distant to the INL Site.
Samples are collected from both single-family farms and commercial
dairies. A 2-liter (0.5-gallon) sample is obtained from each
location monthly, except in Idaho Falls and Terreton where samples are collected
weekly. Milk from each location is analyzed for
Iodine-131 (131I), and one analysis for
tritium at each location is performed during the year.
Milk was the first agricultural product to be monitored,
beginning in at least 1957. The number of samples collected per year has
been relatively constant since about 1962, though locations change as dairies go out of business and are replaced by others.. Because of improvements in
counting technology, the detection limit for 131I has
decreased from about 15,000 pCi/L in early sampling to the current
detection level of about 0.5 pCi/L.
The objectives of ESER's Offsite
Environmental Surveillance Program are:
Sample media representing pathways of contaminants from the INL to
people near the site
Obtain radiological analyses for
Report and interpret the results
of these analyses for the public.