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A � ABOVEGROUND STORAGE TANK ASSESSMENT CALCULATIONS TRACY CHEVROLET 3400 Auto Plaza Way, Tracy, California The 480-gallon (gal) aboveground waste oil tank (AST) has parameters as indicated on Figure 3. AST WEIGHT The 480-gallon AST (AST4B,) has a weight found by extrapolation utilizing a known tank weight for a 350-gal AST (AST 850) . The AST350 has a weight of 730 pounds (lb)when empty and a laden weight of approximately 3,355 Ib. The weight of 480-gal of waste oil, using a conversion factor of 7.5 Ib per gallon, is 3,600 Ib. The AST480 weight is found to be 1,001 Ib. HORIZONTAL SHEAR CALCULATION V = 0.7 x Ca x I x Total AST Empty Weight where: V = Horizontal Shear CS = Seismic Coefficient (Table 16-Q, 1997 Uniform Building Code (UBC)) I = Occupancy Importance Factor (Table 16-k, 1997 UBC)) V = 0.7 x 0.36 x 1.0 x 1,001 pounds force (lb,) = 252 Ibf The horizontal shear is calculated at approximately 252 Ib,. OVERTURN MOMENT CALCULATION OT = [V x Tank Height (HP) x 0.5] - [Total AST Empty Weight x Tank Width (Wp) x 0.5] where: OT = Overturn Moment HP = Tank Height= 39 in WP = Tank Width = 33 in OT = [252 Ib,x 39 in x (1 ft/12 in) x 0.5] - [1,001 Ib x 33 in x (1 ft/12 in) x 0.5] = 409 Ib - 1,376 Ib _ - 973 Ib,ft The tank overturn moment is calculated at approximately-973 Ib,ft.which is less than zero,therefore the tank will not overturn. SAFETY FACTOR CALCULATION SF = [(Total AST Empty Weight x Wp x 0.5)] _ [V x Tank Height (HP) x 0.5] where: SF= Safety Factor SF = [( 1001 Ib x 33 in x (1 ft_ 12 in) x 0.5)] _ [252 Ib,x 39 in x (1 ft/12 in) x 0.5] = 3.7 The safety factor was calculated at approximately 3.7 which is greater than 1, therefore the safety factor is sufficient to not overturn. Note: in = inch ft=foot Ch2o=7.5 Ib/gal=pounds to gallon conversion factor AST empty and laden weights are estimated based on comparable tanks.