Code of Federal Regulations Title 43. Public Lands:  Interior § 43.11.22 Sampling of potentially injured natural resources

(1) Samples necessary to preserve perishable materials considered likely to have been affected by, and contain evidence of, the oil or hazardous substance. These samples generally will be biological materials that are either dead or visibly injured and that evidence suggests have been injured by oil or a hazardous substance;

(2) Samples of other ephemeral conditions or material, such as surface water or soil containing or likely to contain oil or a hazardous substance, where those samples may be necessary for identification and for measurement of concentrations, and where necessary samples may be lost because of factors such as dilution, movement, decomposition, or leaching if not taken immediately;  and

(3) Counts of dead or visibly injured organisms, which may not be possible to take if delayed because of factors such as decomposition, scavengers, or water movement. Such counts shall be subject to the provisions of § 11.71(l)(5)(iii) of this part.