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ASTM D5925-26
Standard Practice for Preliminary Sizing and Delineation of Soil Absorption Field Areas for On-Site Septic Systems
Standard Practice for Preliminary Sizing and Delineation of Soil Absorption Field Areas for On-Site Septic Systems
D5925-26
ASTM|D5925-26|en-US
Standard Practice for Preliminary Sizing and Delineation of Soil Absorption Field Areas for On-Site Septic Systems
Standard
D5925 Standard Practice for Preliminary Sizing and Delineation of Soil Absorption Field Areas for On-Site Septic Systems>
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BOS Vol. 04.09 Committee D18
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ASTM International
Significance and Use
4.1 This practice should be used in conjunction with a surface and subsurface site investigation to delineate a recommended field area that is adequate for any septic system that can reasonably be anticipated for the site. If actual design results in a smaller field area, the boundaries can be modified accordingly.
4.2 Staking and flagging procedures in the practice help prevent accidental disturbance of a recommended septic system field area by equipment traffic and other construction activities prior to installation of the system. Soil disturbance resulting in compaction from heavy equipment traffic or removal by excavation equipment usually invalidates the results of the surface and subsurface investigation that led to recommendation of a field area.
4.3 In the event of suspected disturbance or removal of natural soil in the recommended field area, soil elevation benchmarks established by this practice allow assessment of the actual extent of disturbance or soil removal.
4.4 This practice should also be used where topographic limitations create uncertainty as to whether a potentially suitable field area for a septic system will provide a large enough absorption area to treat anticipated wastewater flows. In such situations clear demarcation of the suitable areas will also provide greater assurance of proper system installation.
4.5 It is assumed that the water table level is below the drain field to ensure proper functioning. Ideally, the water table should be at least 3 to 4 feet below the bottom of the drain field. This allows the soil to adequately absorb and treat the wastewater from the septic system.
Scope
1.1 This practice covers procedures for estimating the dimensions and marking the boundaries of a soil absorption area for an on-site septic system involving residential-strength wastewater. It can also be used to estimate the dimensions of commercial on-site septic systems where wastewater strengths are similar to residential wastewater.
1.2 This practice can also be used for marking the boundaries of the area for a septic system constructed filter bed.
1.3 This practice can be used at any site where a potentially suitable or recommended field area has been identified in accordance with Practices D5879/D5879M and D5921.
1.4 Many jurisdictions have requirements for evaluating sites for approval of on-site septic systems. Therefore, this practice is not meant to be an inflexible description of investigation requirements as.the applicable jurisdictions may require fewer or greater numbers of subsurface features to evaluate a site.
1.5 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units, which are provided for information only and are not considered standard. Reporting of test results in units other than inch-pound shall not be regarded as nonconformance with this standard.
1.6 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.
1.7 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.