decay rate of the isotope(s) present as contamination.
e. The procedures for weathering or aging consist of placing or leaving a contaminated object in
an out-of-the-way area, posting the area with contamination markers, and waiting for the contamination
to drop to an acceptable level. Check the weathering or aging progress periodically by detection and
survey procedures. Consider using weathering or aging in situations where manpower is of primary
a. Soil is a readily available natural decontaminant. The type of soil affects the persistency of
chemical agents. Sandy soil tends to absorb the agent and increases the duration of the vapor hazard.
Rocky soil does not absorb the agent as fast, so it does not increase the persistency.
b. Soil with organic matter will seal or cover contamination and absorb liquid contamination;
however, sandy soil will not absorb any contamination.
c. The procedures for using soil consist of covering a contaminated area with about 10
centimeters (4 inches) of earth. This offers protection against liquid chemical contamination as long as
the earth is not disturbed and the chemical agent is not exposed.
Such an area may be crossed safely, but take care not to disturb the earth covering. If the layer of earth
is broken, both a contact and vapor hazard may result. Extra protection may be obtained by mixing
household bleach with the earth.
In the absence of better absorbents, use earth to remove liquid contamination from materiel. This earth
becomes contaminated and must be treated as contaminated waste.
d. Bury expendable materiel contaminated with chemical or biological agents or with
radioactive material. Earth is only a temporary cover for radiological contamination. Terrain
contaminated by radiation, such as drainage ditches or collection sumps, can be effectively sealed by
using at least 30 centimeters