The Water Guys take a deep dive into aquifers (well, figuratively speaking, of course) to determine what they are and why they are critical. 

The Water Guys are Marvin Nash, Neal Fehringer, John Robitaille, Darren Smith, and Jeff Holder

Links
SynergyForEcologicalSolutions.org
EncoreGreenEnvironmental.com

Produced Water Stats:
http://aqwatec.mines.edu/produced_water/intro/pw/