Question

1. to use groundwater, a well must be drilled ______

into the impermeable layer
into the zone of aeration
into the zone of saturation
above the water table

Explanation:

The zone of saturation is the subsurface layer where all pore spaces are filled with groundwater. Drilling a well into this layer allows access to usable groundwater. The other options are incorrect: impermeable layers do not hold accessible groundwater, the zone of aeration has air in pores with only some moisture, and above the water table is part of the aeration zone with no standing groundwater.

Answer:

into the zone of saturation