Ala. Admin. Code r. 420-3-1-.55

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

Section 420-3-1-.55 - Gravel Field Standard EDF Sizing For Establishments

(1)General Requirements. The procedure for EDF sizing for establishments depends on the estimation of volume and strength of waste. If ADPH determines the waste has not been appropriately characterized, ADPH may offer the option of a temporary Performance Permit so that the applicant may demonstrate the volume and strength of the sewage.

(2)Sizing for High Strength Sewage.

(a) If an establishment has a projected flow of 1,800 gpd or less of high strength sewage, advanced treatment is optional if there is enough room to accommodate the large EDF that will be required without treatment. In that case, paragraph (b) below applies. If advanced treatment is used on high strength sewage (it is required at 1,800 gpd or above), paragraph (c) below applies for sizing.

(b) If advanced treatment is not used, the EDF size is based on average design load in pounds of BOD per day and no reductions may be taken for permitted disposal products.

1. To deternrine the average design load in pounds of BOD per day, refer to 420-3-1-.52 Design Flow and Wastewater Concentrations.

2. To calculate the BOD load to the EDF, assume that the septic tank will remove 30 percent of BOD.

3. Divide the BOD load to the EDF by the appropriate loading rate from Column V of Table 2 or Table 3. This is the bottom area of the EDF.

(c) If advanced treatment is used, then the EDF is sized using the design flow and is calculated by dividing the flow by the appropriate hydraulic loading rate in Column VI of Table 2 or Table 3. This is the bottom area of the EDF. This column gives a reduction in field size for treatment and no other reductions may be taken for permitted disposal products.

(3)Sizing for Sewage.

(a) If the effluent that will come from the establishment is sewage and not high strength sewage, advanced treatment is optional up to 4000 gpd flow or less. If the flow is greater than 4000 gpd1 advanced treatment is required.

(b) If advanced treatment is not used, divide the flow by the appropriate hydraulic loading rate in Column II of Table 2 or Table 3. This is the EDF size. If the flow for the establishment is sewage, a primary EDF shall be a minimum of 300 square feet of the Gravel Field Standard. Permitted disposal products may be used with appropriate sizing.

(c) If advanced treatment is used, divide the flow by the hydraulic loading rate in Column Vl of Table 2 or Table 3. This is the bottom area of the EDF. This column gives a reduction in field size for treatment and no other reductions may be taken for permitted disposal products.

(4)Sizing for Graywater. If advanced treatment is not required, EDF sizing shall be calculated by dividing the flow by the hydraulic loading rate in Column II of Table 2 or Table 3, but the primary EDF shall be a minimum of 300 square feet of the Gravel Field Standard. Permitted disposal products may be used with appropriate sizing.

Ala. Admin. Code r. 420-3-1-.55

New Rule: Filed October 20, 2005; effective November 24, 2005; operative March 19, 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 .81 was renumbered .55 per certification published December 30, 2022; effective February 13, 2023.

Authors: Thad Pittman, Matthew Conner, Ken Stephens, Bob Bright

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