(a) A standard onsite wastewater system consists of a field of perforated pipe:
- (1) Surrounded by gravel or other conventional trench media product authorized by the Department of Health; and
- (2) Installed in such a manner that the clarified effluent from the septic tank or pretreatment unit will be distributed with reasonable uniformity into the natural soil.
- (b) The individual absorption trench should not be more than one hundred feet (100’) without mechanical dosing, and the trench bottom and perforated pipe or gravel substitute should be installed at a grade of zero to two inches (0” – 2”) per one hundred feet (100’).
- (c) In all cases, line length shall not exceed one hundred fifty feet (150’).
- (d) In order to ensure even distribution of the effluent, all onsite wastewater systems utilizing a distribution box shall have absorption trenches of the same length.
- (e) Onsite wastewater systems utilizing serial distribution of the effluent shall be provided with an authorized diversion device to allow drying of the most used absorption trenches.
- (f) The most used absorption trench should be allowed to drain and dry out during the summer months.
- (g) A minimum of two (2) absorption trenches is required to ensure that the absorption area will function even if one (1) absorption trench is disturbed.