Chamber Model = ADS N-12 36" (ADS N-12® Pipe) Inside= 36.1"W x 36.1"H => 7.10 sf x 20.00'L = 142.0 cf Outside= 42.0"W x 42.0"H => 8.86 sf x 20.00'L = 177.2 cf 42.0" Wide + 21.0" Spacing = 63.0" C-C Row Spacing 4 Chambers/Row x 20.00' Long +3.50' Header x 2 = 87.00' Row Length +18.0" End Stone x 2 = 90.00' Base Length 5 Rows x 42.0" Wide + 21.0" Spacing x 4 + 18.0" Side Stone x 2 = 27.50' Base Width 6.0" Stone Base + 42.0" Chamber Height + 24.0" Stone Cover = 6.00' Field Height 20 Chambers x 142.0 cf + 24.50' Header x 7.10 sf x 2 = 3,187.9 cf Chamber Storage 20 Chambers x 177.2 cf + 24.50' Header x 8.86 sf x 2 = 3,978.6 cf Displacement 14,850.0 cf Field - 3,978.6 cf Chambers = 10,871.4 cf Stone x 40.0% Voids = 4,348.5 cf Stone Storage Chamber Storage + Stone Storage = 7,536.4 cf = 0.173 af Overall Storage Efficiency = 50.8% Overall System Size = 90.00' x 27.50' x 6.00' 20 Chambers 550.0 cy Field 402.6 cy Stone