Thanks for sharing, that's really interesting -- but do those contaminants remain in the soil?

It seems like one of the following should be true:

- the treated wastewater being pumped into the ground has been so successfully treated that it doesn't contain more harmful contaminants than ground water, and so it could be just piped through to the same treatment as ground water, saving a pump-into-ground + pump-out-of-ground cycle

- the treated wastewater being pumped into the ground contains harmful contaminants at a greater concentration than existing ground water, which the soil may mediate before being pumped back up for further treatment -- but the concentration of these contaminants in the soil will increase as a result