Re: FGR-13

[BKellyiem <BKellyiem@aol.com>]

Mr. Rollins,

In the preamble to HEAST, the EPA says the following:

"Ingestion and inhalation slope factors are central estimates in a linear
model of the age-averaged, lifetime attributable radiation cancer incidence
(fatal and nonfatal cancer) risk per unit of activity inhaled or ingested,
expressed as risk/pCi.  External exposure slope factors are central estimates
of lifetime attributable radiation cancer incidence risk for each year of
exposure to external radiation from photon-emitting radionuclides distributed
uniformly in a thick layer of soil, and are expressed as risk/yr per pCi/gram
soil."

I hope that this answers your question.  Let me know if it doesn't.

Brian Kelly, CHP
bakelly@iem-inc.com