Question

Is groundwater contaminated by sewage from a ruptured septic tank can sometimes be naturally purified by flowing for a relatively short distance through a _ _ __.

Answer 1

sandstone aquifer

Answer 2

The choices can be found elsewhere and as follows:

sandstone aquifer
fractured limestone aquifer
cavernous limestone aquifer
spring where the water table intersects the ground surface

I think the correct answer is the second option. Groundwater contaminated by sewage from a ruptured septic tank can sometimes be naturally purified by flowing for a relatively short distance through a fractured limestone aquifer.