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

Comment
Number
3-7
3.a.23 p. 7.2.12, DOE/ET-0028 According, to Section 7.4.5 of DOE/ET-0028, the repository is operating
Section 7.2.2.4 leaves the impression that basalt has a low permeability.
There are many situations in which this is-not the case, e.g., Idaho
Falls, or the domestic water sources on the Hawaiian and Canary Islands.
Comment
Numbe
3-8
around the clock for a total of 175 days/year or 4200 hours/yr. This
means that canisters are disposed of at a rate of 10 per hour, when 12,000
MTHM/hr are received. Considering the remote handling required these
rates appear unrealistically high. The design of handling systems to
3.b Waste Form and Packaging accomplish this should be presented.
3.b.1 p. 4.. 3.c.3 p. 3.1.30 and 3.1.116
The s 3rd s p tt h f d bd c n ws i d in a
The 3rd paragraph states that fluid bed calcination was identified in a
previous report (ERDA 76-43, Vol. 2, Chapter 6) as being the most well-
Sc p a, t , h b
developed calcination process and, therefore, has been selected as the
reference calcination process for this report. However, page 4.1.4 states
GEIS states that: "The effects of rock discontinuties on rock strength
are difficult to evaluate..." "A structural system of grounded rock bolts,
wire mash and shotcrete effectively support this type of ground (shalq)."
"The shale surfaces can be protected...to prevent slaking" (p. 3.1.30).
that the reference vitrification processs is spray calcination/in-can
melting. The' report should clarify why one calcination process is refer-
enced to make glass waste form and another to make a calcine waste form.
Ground support in a shale repository at depths of about 600 m is likely to
be a major and costly problem. It is more likely that reinforced concrete
shields will have to be used extensively in all main corridors, crusher
3.c Design and Operation
gn and O n rooms and places that have to be kept open for retrievability. Support
system will likely be similar to that used in the Washington Metro or in
o
3.c.1 p. 1.9/1.10 the Clear Creek Tunnel. The support costs on p. 3.1.116 for shale are
The staff has attempted to corroborate the numerical values given in
clearly underestimated.
Tables 1.1 and 1.2. In attempting to understand the bases for the tables
3.c.4 p. 3.1.31
and the connection between them, other parts of the GEIS and the supporting
documents were s d. "Under high stresses and temperatures the room closure rates may be high...
documents were searched. Neither the numerical values nor the relationship
een the two tabes could be sustantiated, engineered support would be necessary... A support system can be provided...."
between the two tables could be substantiated. Therefore, we recommended
that you provide a detailed explanation in the GEIS text of the method
thayo t e a e T de. in e e e Since closure rates are expected to be high, the GEIS should describe the
thereby the numberical values of Tables 1.1 and 1.2 were developed. It
. support systems and expected closure rates and the effectiveness of the
would be helpful if intermediate tables were prepared which indicate how
Table 1.1 relates tp Table 1.2. The headings (or footnotes) on Table 1.1 support systems.
should clearly indicate what HLW or TRU wastes are included in each column.
3.c.S pp. 3.1.35, 3.3.12, K.2, K.3, K. 11
3..2 . 2.1.22 pp. 7.3.6, 7.3.12, 7.4.2; 00E/ET-0028
The rates of receipt of spent fuel at the repository are presented. The
maximum receipt rate of 12,000 MTHM/yr converts to 40,400 canisters/yr
(assuming 0.297 MTHM/canister nraised per Table 2.1.8).
The GEIS evaluates the impacts of 5 year and 25 year retrievability.
Given the uncertainties concerning geologic emplacement in mined repositories
by the IRG and the GEIS which must be addressed by site specific