310 C.M.R. 15.245 – Soil Absorption System Siting Requirements

(1) Systems serving new construction shall not be sited in areas with percolation rates slower than 60 minutes per inch.
(2) When recorded percolation rates are between those listed in 310 CMR 15.242, the next slower rate shall be used for design purposes.
(3) Surface and subsurface drainage shall be directed away from the soil absorption system.
(4) Approval of a soil absorption system in soils with a recorded percolation rate of between 60 and 90 minutes per inch may be granted only for upgrades of existing systems with no increase in design flow. In such cases, the soil absorption system design shall be based on a maximum effluent loading rate of 0.15 gpd/square foot.