Wisconsin Pesticide Applicator Commercial Category 6 Practice Test

Point source pollution is contamination that enters water from a single, identifiable source, such as a pipe, channel, or specific spill. A pest spill entering a storm sewer at mixing and loading sites fits this idea because it originates from one known location and discharges into the sewer system that feeds a water body. The other scenarios involve diffuse sources: runoff from a turf area occurs across many parts of the landscape; leaching through soil happens over a broad area as water moves through the soil profile; drift onto off-target properties is aerial movement from multiple application points landing elsewhere. So the spill into the storm sewer is the clear example of a point source.