N.J. Admin. Code § 7:9A-11.2 - Design requirements

(a) The percolating area shall be considered to be the total outside surface of the seepage pit lining below the inlet and exclusive of any soil horizons with a percolation rate slower than 40 minutes per inch. The bottom of the seepage pit shall not be counted as part of the percolating area.

(b) The minimum required percolating area for dwelling units shall be determined from the following table, based upon a weighted average, of the percolation rates of all the soil layers exposed in the sidewalls, determined as prescribed in 7:9A-6.4(f)4. In no case, however, shall the percolating area be less than 110 square feet per dwelling unit.

Average	Minimum Area
Percolation Rate	Per Bedroom Per Day
(Min/inch)	(Square feet)
10 or less	72
11 to 20	108
21 to 30	144
31 to 40	180
over 40	not acceptable

(c) The minimum percolating area for facilities other than individual dwellings shall be determined from the following table based upon the volume of sanitary sewage, determined as prescribed in 7:9A-7.4, and a weighted average of the percolation rates of all soil layers exposed in the sidewalls, determined as prescribed in 7:9A-6.4(f)4. In no case, however, shall the percolating area be less than 110 square feet.

Average	Minimum Area
Percolation	Per Gallon Per Day
(Min/inch)	(Square feet)
10 or less	0.48
11 to 20	0.72
21 to 30	0.96
31 to 40	1.20
over 40	not acceptable

Notes

N.J. Admin. Code § 7:9A-11.2