From North Dakota comes word of a record oil and gas spill. No, not the petroleum itself, but the wastewater from the fracking process. And these days there’s a lot of it.

The water could be toxic, even though federal rules exempt it from treatment as hazardous waste. Fracking pumps huge volumes of water into the well, and even more comes back out. A typical well can spit about 1,000 gallons a day. Some of the water is recycled back into fracking, stored in pits or used to de-ice roads. It’s also injected deep underground, which has been known to cause earthquakes.