Question 122: The conforming amendment to 10 CFR 50.73 (a)
(2) states that reports submitted in accordance with 10 CFR
50.73 (a) (2) (viii) also meet the effluent release
reporting requirements of 10 CFR 20.2203 (a) (3). However,
10 CFR 20.2203 (a) (3) requires reporting of concentrations
in an unrestricted area of 10 times any applicable limit in
Part 20 while 10 CFR 50.73 (a) (2) (viii) requires reports
of airborne or liquid effluent releases that exceed 20
times the applicable concentration limits in Table 2,
Appendix B. Why is the multiple ten in one case and twenty
in the other?
terms of public dose. The annual dose limit for a member
of the public is 100 mrem. 10 CFR 20.2203 (a) (3) requires
reporting above a threshold of ten times this applicable
limit, or 1000 mrem. The concentrations in Table 2,
Appendix B, correspond to an annual dose of 50 mrem;
therefore, the requirement in 10 CFR 50.73 (a) (2) (viii)
for reporting at 20 times these concentrations corresponds
to a reporting threshold in terms of annual dose, of 20 x
50 mrem, or 1000 mrem, which is the same dose threshold as
that in 10 CFR 20.2203 (a) (3). (References: 10 CFR
20.2203, 50.73)