6. Gasoline vapors are vented to the atmosphere when an underground gasoline storage tank is filled. If the tanker truck discharges into the top of the tank with no vapor

control(known as the splash fill method), the emission of gasoline vapors is estimated to be 2.75 kg/m of gasoline delivered to the tank. If the tank is equipped with a pressure relief valve and interlocking hose connection and the tanker truck discharges into the bottom of the tank below the surface of the gasoline in the storage tank, the emission of gasoline vapors is estimated to be 0.095 kg/m³ of gasoline delivered (Wark et al., 1998). Assume that the service station must refill the tank with 4.00 m³ of gasoline once a week. Draw amass-balance diagram and estimate the annual loss of gasoline vapor (in kg/y) for the splash fill method. Estimate the value of the fuel that is captured if the vapor control system is used. Assume the density of the condensed vapors is 0.800 g/mL and the cost of the gasoline is $1.06 per liter.