1.1 This guide covers the use of existing wells for environmental site characterization and monitoring. It covers the following major topics: criteria for determining the suitability of existing wells for hydrogeologic characterization and ground-water quality monitoring, types of data required to document the suitability of an existing well, and the relative advantages and disadvantages of existing large- and small-capacity wells.

1.2 This guide should be used in conjunction with Guide D 5730, that provides a general approach for environmental site investigations.

1.3 This guide does not specifically address design and construction of new monitoring or supply wells. Refer to Practices D 5092 and D 5787.

1.4 This guide does not specifically address ground-water sampling procedures. Refer to Guide D 5903.

1.5 The values stated in SI units are to be regarded as the standard. However, dimensions of materials used in the water well industry are given in inch-pound (English) units by convention, therefore, inch-pound units are used where necessary in this Guide.

1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.