Management of Commercially Generated Radioactive Waste - U.S. ...

5.69
TABLE 5.4.26. 70-Yr Whole-Body Dose Commitments to
Maximum Individual from Drop
of Waste Canisters into a Geologic
Repository
High-Level
70-Yr Dose
Waste Commitment, rem
Calcine 1.2 x 10 -4
Glass 1.4 x 10 -5
RH-TRU 1.7 x 10 -7
In summary, radiological aspects of repository construction and routine operation
including reasonably forseeable accidents while filling and decommisioning the repository
do not constitute a significant impact on public health and safety.
5.4.6.7 Radiological Impacts of Operating Accidents on the Work Force
In the case of reprocessing waste, the calculated first-year total-body dose to a mem-
ber of the repository work force near the point of impact of four canisters of high-level
waste dropped down a mine shaft would be 26,000 rem for waste in glass, about 210,000 rem
for the waste in calcine form, and about 7,600 rem for the spent fuel case; all fatal
doses.(a) The exposure rate in the corridor due to contamination of surfaces would be
approximately 20 R per hour from the waste (about 5 R per hour in the case of spent fuel).
Such exposure rates would make decontaminating the corridor impossible by ordinary means;
some sort of remote operation similar to that of dismantling a reactor core would be needed.
However, design changes to the transfer stations in the repository and the use of two stages
of HEPA filtration between the shaft and other portions of the mined repository would prob-
ably lower the occupational doses to repository workers to within acceptable ranges. These
changes would limit the area contaminated to the transfer station and possibly the canistered
waste (CW) shaft; although air flow should preclude significant contamination in the
CW shaft. Limiting the contaminated area should also decrease the time required for decon-
tamination and resumption of repository loading.
5.4.6.8 Other Environmental Impacts
An artist's rendering, based on engineering data, of the above-ground facilities asso-
ciated with a geologic repository was shown in Figure 5.3.1. With the exception of the mine
spoils piles, these facilities would not be expected to be any more of a detraction than any
other mining or industrial facility of comparable size. Although the exclusion boundary
could be viewed as a detraction in itself, the exclusion area will likely limit the visual
impacts of the above-ground repository facilities.
(a) The source terms used in these calculations are believed to be unrealistically pessimistic
but additional engineering analysis is necessary before the source terms can be
reduced with confidence.