This practice should be used as the initial step for evaluating a site for its potential to support an on-site septic system and to determine the best location for subsurface observations as covered in Practice D 5921.

This practice should be used by individuals involved with the evaluation of properties for the use of on-site septic systems. Such individuals may be required to be licensed, certified, or meet minimum educational requirements by the local or state regulatory authority. Generally, such individuals should be familiar with the appropriate regulatory requirements governing the design and placement of on-site septic systems for the area of the site being investigated, and at least some experience or training in geomorphology, soils, geology, and hydrology.³

This practice is one step in the design of an on-site septic system that also includes subsurface characterization, see Practice D 5921, staking and protection of the soil absorption or constructed filter bed area, see Practice D 5925, selection of system type, and design of the system size and configuration. Typically, the same individual will perform the surface and subsurface characterization of a site. Local regulation and practice will determine whether the same individual is responsible for all steps in the process of locating and designing an on-site septic system. Effective surface and subsurface characterization of a site for on-site septic systems, however, requires some knowledge of the following for the county or state in which the site is located: (1) on-site septic system types typically used for different soil conditions, and (2) typical soil absorption/filter bed areas required for different wastewater flow rates and areal soil wastewater loading rates.

1.1 This practice covers procedures for the characterization of surface conditions at a site for evaluating suitability for an on-site septic system for disposal and treatment of wastewater. This practice provides a method for identifying potentially suitable areas for soil absorption of septic tank wastewater.

1.2 This practice can be used at any site where on-site treatment of residential and nonhazardous commercial wastewaters using septic tanks and natural soils or constructed filter beds is required or an option under consideration. This practice may also be useful when constructed wetlands are used as an alternative wastewater treatment method.

1.3 This practice should be used in conjunction with Practices D 5921 and D 5925.

1.4 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word "Standard" in the title of this document means only that the document has been approved through the ASTM consensus process.