Beds or Fields

(1) The use of leaching beds or fields is restricted to systems with a calculated design flow of less than 5,000 gpd per leaching bed or field. (2) Bed or field specifications: (a) Minimum number of distribution lines = 2. (b) Length - 100 feet maximum. (c) Slope of distribution lines - 0.005 feet per foot. (d) Separation distance between lines - six feet maximum. (e) Lateral separation distance between lines and edge of the bed - four feet maximum. (f) Separation distance between adjacent beds/fields - ten feet. (g) Aggregate depth (below the invert of the distribution lines) - six inches minimum, 12 inches maximum. (h) Distribution lines - refer to 310 CMR 15.251(5) through (10) (Trenches). (i) Effective leaching area - shall include only the bottom area, not the sidewalls.