Ala. Admin. Code r. 420-3-1-.39

Current through Register Vol. 43, No. 1, October 31, 2024

Section 420-3-1-.39 - Soil Permeability

(1) Permeability shall be determined as part of a site evaluation by one or more of the following methods: The percolation testing method described in 420-3-1-.43 General Percolation Procedure through 420-3-1-.46 Extended Saturation Procedure.

(a) The unified method described in 420-3-1-.47 Unified System for Site Evaluation.

(b) The soil morphology method described in 420-3-1-.48 Soil Morphology Method.

(c) The detailed soil mapping method described in 420-3-1-.49 Soil Maps.

(d) The percolation method, when used, shall be performed and certified by an engineer, land surveyor, geologist, or soil classifier, in accordance with their respective licensing board rules.

(2) Permeameter testing may be substituted for percolation tests when performed in accordance with the manufacturer's guidelines and procedures, with the exception of saturation. Saturation periods shall be the same as for percolation testing found in 420-3-1-.43 General Percolation Procedure.

(a) Permeameter tests maybe required to be performed in lieu of percolation tests in special conditions, such as in fill material, at the discretion of ADPH or the LHD.

(b) The unified soils classification method, when used, shall be performed and certified by an engineer or geologist according to 420-3-1-.47 Unified System for Site Evaluation.

(3) The soil morphology method, when used, shall be performed and certified by a soil classifier or PHESS currently employed by ADPH, according to 420-3-1-.48 Soil Morphology Method.

(4) The detailed soil mapping method, when used, shall be performed and certified by a soil classifier according to 420-3-1-.49 Soil Maps.

(5) Soil absorption rates for an EDF or discharge area shall be based on actual percolation results or assigned rates determined by using one of the other three methods of site evaluation. Although similarities exist, each method has specific procedures, soil groupings, terminology, and application ranges to be used and reported exclusively by the appropriate professional as set forth in this rule.

(6) When assigned or actual permeability (percolation) rates or other test results are in dispute, ADPH or the LHD shall determine what test results or percolation rates are used in permitting an OSS/EDS.

(7) Test results or assigned rates obtained from natural soil, along with all other evaluation factors, shall be used to determine the design and size of the system. However, test results or assigned rates in fill material may not necessarily be the only criteria for determining the type or size of an EDF. Other requirements may apply as deemed necessary by ADPH or the LHD.

(8) ADPH or the LHD may require additional observation pits, borings, or other tests as necessary, if ADPH or the LHD becomes aware that the soil or site may be significantly different from that which was reported. Other tests may include, but are not limited to, saturated hydraulic conductivity tests (such as constant head permeameters), extended saturation testing, and/ormonitoring of saturated conditions.

Ala. Admin. Code r. 420-3-1-.39

Filed July 20, 1988. Repealed and New Rule: Filed December 16, 1999; effective January 20, 2000. Repealed and New Rule: October 20, 2005; effective November 24, 2005; operative March 19, 2006. Amended: Filed October 19, 2006; effective November 23, 2006.

Adopted by Alabama Administrative Monthly Volume XXXV, Issue No. 04, January 31, 2017, eff. 3/5/2017.

Adopted by Alabama Administrative Monthly Volume XLI, Issue No. 03, December 30, 2022, eff. 2/13/2023.

Previous Rule .63 was renumbered .39 per certification published December 30, 2022; effective February 13, 2023.

Authors: David Gray, Boyd Rogers, Richard Smith

Statutory Authority:Code of Ala. 1975, §§ 22-2-2(4); 22-2-2(6); 22-10-1, et seq.; 22-26-1et seq.