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

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

72<br />

CONSEQUENCE.ANALYSIS<br />

on a sound basis. Research to do this should be identified in the section on research and<br />

development needs. (218-001)<br />

Draft p. 3.1.155, last paragraph--This is an improper combination:<strong>of</strong> probabilities.<br />

If the probabilities are multiplied together, as has been done here, the result is the prob-<br />

ability <strong>of</strong> all three conditions occurring in the same year. If the probabilities are.taken<br />

over 10,000 years, for example, the probability <strong>of</strong> a fault intersecting the repository is<br />

-7<br />

4 x 10 -7 . The probabilities <strong>of</strong> failure <strong>of</strong> waste containment, or <strong>of</strong> aquifer intersection,<br />

over this period are likely to be one, each. The total probability is therefore about<br />

4 x 10 -7 , not 4 x 10 -15 . (113-EPA)<br />

Response<br />

The total probability <strong>of</strong> release, 4 x 10- 15 is for one year. The probability dis-<br />

cussed on draft p. 3.1.155 is referred to as "total probability" because it is the product<br />

<strong>of</strong><br />

- a fault intersection in the repository 4 x 10-11/yr<br />

- a failure <strong>of</strong> a waste container 10-2/yr<br />

- chance <strong>of</strong> aquifer intersection which leads to biosphere 10- 2 /yr<br />

The text was changed to make clear that the total annual probability isbeing referred to.<br />

In order to assure conservation, this final statement uses a value <strong>of</strong> 4 x 10 11 for the<br />

total probability <strong>of</strong> release for one year and a probability <strong>of</strong> 4 x 10 -7 for the 10,000<br />

year period, as suggested by EPA.<br />

Draft p. 3.1.67<br />

Issue<br />

One commenter noted that the statement pointing out that 90Sr and 226 Ra dominate the<br />

health effects <strong>of</strong> a release <strong>of</strong> radioactivity from a repository needs discussion. (40)<br />

Response<br />

This statement is actually discussing consequence analysis. 9Sr and 226 Ra were used<br />

as examples. The importance <strong>of</strong> these nuclides at different times can be found in final<br />

Sections 5.4 and 5.5 or in Chapters 4.0 and 9.0 <strong>of</strong> DOE/ET-0029.<br />

Draft p. 3.1.67<br />

Issue .<br />

Several commenters questioned the probabilities in Table 3.1.3.

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

Saved successfully!

Ooh no, something went wrong!