1.1 This guide provides descriptions of various methods for site characterization along with advantages and disadvantages associated with each method discussed. This guide is intended to aid in the selection of drilling method(s) for geotechnical and environmental soil and rock borings for sampling, testing, and installation of wells, or other instrumentation. It does not address drilling for foundation improvement, drinking water wells, or special horizontal drilling techniques for utilities.

1.2 This guide cannot address all possible subsurface conditions that may occur such as, geologic, topographic, climatic, or anthropogenic. Site evaluation for engineering, design, and construction purposes is addressed in Guide D420. Soil and rock sampling in drill holes is addressed in Guide D6169. Pertinent guides and practices addressing specific drilling methods, equipment, and procedures are listed in Section 2. Guide D5730 provides information on most all aspects of environmental site characterization.

1.3 The values stated in either SI units or inch-pound units (given in brackets) are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.

1.4 This guide does not purport to comprehensively address all methods and the issues asso