Because the real quench distance is only the minimum figure @ TDC (which is not the point of maximum risk), and there is measurable pumping loss getting those few molecules in and out of that small space, and as the clearance expands the loss is reduced.
Why is nonpoint source pollution potentially more harmful than point source pollution? a. Nonpoint source pollution disrupts the water cycle. b. Nonpoint source pollution is difficult to regulate. c. Nonpoint source pollution comes from more than one source. d. Nonpoint source pollution is more damaging to living organisms than point source pollution. Nonpoint source pollution generally results from land runoff, precipitation, atmospheric deposition, drainage, seepage or hydrologic modification.
This runoff is called agricultural non-point source pollution, because it cannot be traced back to one source, like pollution from a factory can be. Agricultural non-point source pollution is the dominant source of water pollution in China, and it also serves to increase soil erosion and reduce the productivity of the land.