The Environmental Protection Agency (EPA) is updating a 30 year old Clean Water Act program which regulates what type of waste oil and gas companies can send to sewer treatment plants, or publically owned treatment works (POTWs) for disposal. In the past oil and gas companies have sent millions of gallons of their wastewater to these sewage treatment plants, which then discharge it to our rivers, lakes and bays.
But "unconventional" operations - activities like fracking and other modern technologies that enable the industry to access previously untapped reserves of oil and gas - produce a different type of waste. Which is a problem. These plants were never designed to treat this new type of wastewater.