This standard practice identifies recognized methods by which soil@ rock@ and groundwater conditions may be determined. The objective of the investigation should be to identify and locate@ both horizontally and vertically@ significant soil and rock types and groundwater conditions present within a given site area and to establish the characteristics of the subsurface materials by sampling and in situ testing. Laboratory testing of soil and rock samples is governed by other AASHTO and ASTM standards. This standard may involve hazardous materials@ operations@ and equipment. This standard does not propose to address all safety concerns associated with its usage. It is the duty and responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Note 1??The values stated in SI units are to be regarded as the standard.