A 100m tall chimney emits sulphur dioxide at a rate of 2.5kg/s in a highly buoyant plume. The plume rise (∆h) after exiting the chimney follows a trajectory which is given by the equation: ∆h = 0.13 x2/3 (all dimensions in metres). The wind speed is 10m/s and the local ground roughness length is zo = 0.01m. What is the ground level concentration along the x-axis at a distance of 2.5km down wind of the chimney? [Answer: 1400 µg/m3 ]