Question

A landfill in minnesota receives an average of 50 cm of rainfall per year. 60 percent of the water runs off the landfill without infiltrating the surface. the landfill has a surface area of 5000 m2. what is the volume of water that annually infiltrates the landfill?

Answer 1

Since we are given that 60% of the water runs off the landfill without infiltration, the amount of water that actually infiltrates the landfill is 40% of the total volume. Converting the average rainfall per year to meters will give us an answer of 0.50 m. 

We calculate the volume by the equation,
                              V = (area of base) x height
                             V = (5000 m²) x (0.50 m) = 2500 m³
Because the actual percentage of infiltration is 40%, we multiply this value by 0.40 to give us an answer of 1000 m³.