e9dd6711_Soil_sampling__RISK_CONTROL
[SPECIFIC JOB STEPS] The type of sample, grab or composite, will vary depending upon the constituent being identified. While grab samples come from one location, composites come from several locations and are joined to form one sample. When sampling for non-volatiles or semi-volatiles, several composite samples are preferred, with confirmatory grab samples. [RISK ASSESSMENT] Possible loss of volatiles in composite samples. [RISK CONTROL] 
When volatiles are in question, care must be taken when collecting composite samples to minimize the loss of volatiles during handling. In order to minimize handling of volatiles, several grab samples are preferred, with confirmatory composite samples.
Soil sampling
RISK CONTROL