A farmer is analyzing cross sections of his land to determine where to build a well. Which phrase describes the best area to dig down to the groundwater?

A well must reach the saturated zone, where the ground’s pores are filled with water. If that zone begins 15 meters below the surface, the farmer needs to dig less deeply than where the water table is 100 meters down. A thick unsaturated zone or surface clay layer does not indicate a shallower supply of groundwater.

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