Across the U.S., state and local codes vary in how much separation is required below the infiltrative surface to the limiting condition for the soil treatment area. The variation is based on several factors, including the effluent quality, groundwater mounding and risk assessment. The two most common limiting conditions used in designs are a water table (either seasonal or standing) and bedrock, both of which will not adequately treat wastewater before returning it into the environment.The water table is typically evaluated using the soil color, as it is an indicator of natural drainage conditions. A specific kind of mottle occurs in
How Much Separation Do You Need?
A lot of factors must be considered to determine the separation required between the infiltrative surface and the limiting condition of an STA
Jun 05, 2017
| by Sara Heger, Ph.D. |
