23.04.2013 Views

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

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

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

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Response<br />

68<br />

CONSEQUENCE ANALYSIS<br />

The definition <strong>of</strong> design basis and non-design basis appears in final Section 3.2. The<br />

so-called "what-if" accidents are considered to be in the non-design basis category.<br />

Issue<br />

Several commenters questioned the time frames used in the accident analysis, recommen-<br />

ding investigations <strong>of</strong> both earlier times as well as later times.<br />

Draft p. 1.20--It is amusing to see the "summary <strong>of</strong> estimated long-term radiological<br />

impacts <strong>of</strong> worst case what-if accident scenarios for breach <strong>of</strong> repository 1000 years after<br />

closure" when no one knows how to calculate the likelihood <strong>of</strong> a nuclear war within, say, the<br />

next 20 years. (108)<br />

Draft p. 1.20--It does not seem adequate to restrict the EIS to only 1000 years, when<br />

it is dealing with radioactive waste which will not decay for up to several hundred thousand<br />

years. (142)<br />

Draft pp. 3.1.165, 168--Basing the drilling and solution mining scenarios on a<br />

1000 year time interval is not defensible and causes significant alteration <strong>of</strong> the predicted<br />

dose consequences. These time intervals should be reduced, preferably to approximately<br />

250 years. (198)<br />

Draft pp. 3.1.165-172--These discussions do not represent "worst-case" scenarios<br />

because the intrusions take place 1000 years in the future rather than 500 or 100 years in<br />

the future. (114)<br />

Response<br />

The analysis <strong>of</strong> the impacts <strong>of</strong> long-term (non-design basis) accident scenarios at a<br />

geologic repository was generally performed at four points in time: at year 2,050,<br />

+1000 years, +100,000 years, and +1,000,000 years (solution mining was only examined at<br />

+1000 years). The occurrence <strong>of</strong> such events at the time <strong>of</strong> repository closure is highly<br />

unlikely. The use <strong>of</strong> +1,000 years was to contrast the impacts for shorter surveillance<br />

times. The maintenance <strong>of</strong> institutional control for 1000 versus 100 years was not con-<br />

tended. The later time frames provide additional points <strong>of</strong> reference with which to view the<br />

accident consequences. Examination <strong>of</strong> additional time periods would yield similar results.<br />

Draft p. 1.20, Table 1.4 and p. 3.1.173, Table 3.1.54<br />

Issue<br />

There were a number <strong>of</strong> errors and inconsistencies in these two tables. (154)

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!