FIG. 11. Conceptual distribution of carbon tetrachloride from waste disposed at the 216-Z-9 site for (a) 1966, (b) 1974, (c) 1993, and (d) 2005. These figures are based on the results of the base case simulations. Note that some sensitivity simulations show significantly different results. The figure for the year 2005 shows the conceptual impact of soil vapor extraction remediation operations.