The on-site sewage disposal program provides requirements for construction permits and proper location and construction of individual sewage systems to prevent ground and surface water contamination.
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Alternative Treatment System - consists of three types of mound systems.
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Elevated Mound (pump to gravity) is an alternative method of on-site sewage treatment and disposal in which sand fill media is laid on top of properly prepared original soil surface. The sand fill media uses vertical separation to provide the necessary treatment. Pumps are utilized in this type of system. The effluent out of the septic tank flows by gravity to the dosing chamber where it is pumped up to the absorption system installed on top of the sand fill. The effluent then flows by gravity throughout the laterals of the absorption system. The entire system is not pressurized.​
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Gravity Mound is an alternative method of on-site sewage
treatment and disposal in which sand fill media is laid on top of properly prepared original soil surface. The sand fill media uses vertical separation to provide the necessary treatment. Pumps are not utilized for this type of system. The effluent out of the septic tank flows by gravity to the absorption system installed on top of the sand fill.​​​
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Pressure Mound is an alternative method of on-site sewage treatment and disposal in which specified sand fill media is laid on top of a properly prepared original soil surface. The pressure distribution system and wastewater distribution cells are then placed entirely within the filter media at such a level that the desired vertical separation to provide the necessary treatment exists. The fill material provides a measurable degree of wastewater treatment and allows effluent dispersal into the natural soil environment for final treatment.​​
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Conventional System - consists of a septic tank and drainfield.
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Advanced Treatment Unit or ATU, which is a manufactured and packaged mechanical treatment devices that provides additional biological treatment to sewage by mixing air (oxygen) and aerobic and facultative microbes with the wastewater. These units can be categorized as either: 1) suspended growth, 2) attached growth (submerged fixed media) or 3) combination of both.