• The probabilities are not very large, even for small (and thus impractical)grid sizes.The highest calculated value, for a 10 kilometer grid, isapproximately 15 percent (for D/5), which is not very high—it is equivalent to a false-negative probability of approximately 85 percent.• As would be expected, a large grid constant would be more efficient in detecting effluents released during stable conditions, compared to releases under unstable conditions, since the latter would disperse much more quickly, and thus be lost to the samplers from most locations.However, decreasing the grid constant does not cause thecollection of samples to be much more efficient for the more stable conditions. Although the efficiency of collection during unstable conditions would be greatly increased, it would still not be the sameas for the other conditions, even at the much smaller grid size.• Decreasing the grid constant by a factor of 2—from 100 to 50 kilometers—will increase the probability of sampling by a factor of almost 4 for the unstable categories, while increasing the probability by a factor less than 2 for the most stable condition: F/2.