Any wastewater holding facility must conform to the requirements for seepage control specified in paragraphs (1) and (2) of this section. Any facility in an area underlain by clean sands, fractured limestone, or other strata with exceptionally high permeability may be subjected to additional seepage control requirements. (1) Seepage Control. A wastewater retention facility shall be constructed in clay soils or lined with a suitable lining material to prevent contaminated wastewater from reaching groundwaters of better chemical quality. (2) Permeability data. Permeability tests may be required to show that pond liners are adequately impermeable to prevent excessive seepage. The acceptable seepage rate from ponds must be less than 0.1 acre-foot of wastewater per surface acre of pond per year. The acceptable permeability coefficient must be equal to or less than 1.0 x 10-7 centimeters per second at one foot of head and with one foot of permeable material or the equivalent or better thereof. The permeability coefficient must be determined by constant head laboratory permeability tests. The registrant shall furnish certification, signed, sealed, and dated by a licensed professional engineer or licensed professional geoscientist, that the completed pond lining meets the appropriate criteria described in this section prior to using the facilities. |
