• Consider a plume from a stack that is 52.5 m tall. The plume is slightly buoyant, and it levels off at an elevation 13.4 m above the stack exit. The air pollutant under consideration is absorbed when it contacts the ground, has a PEL of 30 mg/m 3, and is emitted from the stack exit at a steady rate of 43.6 kg/s. On a fall afternoon during a Penn State football game, the average wind speed is 3.97 m/s. We are interested in the air quality at x = 2.25 km directly downwind of the plume near the ground outside (not inside the stadium). Assume flat ground between the stack and the location of interest. (a) Calculate the mass concentration in mg/m ³ on the centerline of the plume at this x location and at ground level.
• (b) Repeat for a person standing there breathing through his/her nose.