of water.
However, as Table 2 shows, there is insufficient evidence
from the test program to support a conclusion concerning how K-factors
vary with depth of water.
A similar effect should result from detonations over very hard
substrates such as rock because of the tendency toward the production
of smaller particles, with, perhaps, higher specific activities. The
crater volume from a near-surface detonation is not considered a good
indicator of the value of Ky >» although both crater volume and Ky
decrease
(and the average specific activity increases) with increased
height of burst.
Under these circumstances, the Subcommittee recommends that
DCPA assume for all practical purposes that no soil or substrate
effect exists.
If there is such an effect, the common soils in
the country, being wetter than dry desert alluvium, should yield
slightly lower Kj's and thus this recommendation will produce
conservative results.
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