Chamber Model = ADS N-12 24" (ADS N-12® Pipe) Inside= 23.8"W x 23.8"H => 3.10 sf x 20.00'L = 62.0 cf Outside= 28.0"W x 28.0"H => 3.92 sf x 20.00'L = 78.4 cf 3 Chambers/Row x 20.00' Long = 60.00' Row Length +10.0" End Stone x 2 = 61.67' Base Length 1 Rows x 28.0" Wide + 10.0" Side Stone x 2 = 4.00' Base Width 4.0" Stone Base + 28.0" Chamber Height + 4.0" Stone Cover = 3.00' Field Height 3 Chambers x 62.0 cf = 186.0 cf Chamber Storage 3 Chambers x 78.4 cf = 235.2 cf Displacement 740.0 cf Field - 235.2 cf Chambers = 504.8 cf Stone x 40.0% Voids = 201.9 cf Stone Storage Chamber Storage + Stone Storage = 387.9 cf = 0.009 af Overall Storage Efficiency = 52.4% Overall System Size = 61.67' x 4.00' x 3.00' 3 Chambers 27.4 cy Field 18.7 cy Stone