Collect soil samples where there are noticeable changes in color, texture, and composition. Collect soil samples at a depth that is consistent with the depth from which the questioned soil may have originated. Submit a map identifying soil sample locations. Do not remove soil adhering to shoes, clothing, and tools. Do not process tools for latent prints.
Air dry the soil and the clothing and package separately in paper bags.
Carefully remove soil adhering to vehicles. Air dry the soil and package separately in paper bags. Submit known and questioned soil in separate leakproof containers such as film canisters or plastic pill bottles. Avoid using paper envelopes or glass containers. Pack to keep lumps intact.