Drilling and hydraulic fracturing a well is only half the story when it comes to the water used in oil and gas exploration.
After the well is drilled, after the target formation is fractured and as the oil and gas begins flowing up the well, wastewater comes along with it.
As Colorado Springs and El Paso County wrestle with the sudden interest in drilling in the area, what to do with that wastewater is a big concern.
As much as half of the fluid used to fracture the rock gradually returns to the surface as flowback water, emerging from the well along with the oil and gas over a period of weeks.
Many rock formations, including the Niobrara, also contain water, often briny and laden with minerals, that comes out of the well as what is called produced water, over several years.
“Produced water can be nasty, nasty stuff; other places you can drink it,” said Thom Kerr, acting director of the Colorado Oil and Gas Conservation Commission (COGCC), which oversees oil and gas drilling in the state.
Getting rid of flowback and produced water is a challenge for drilling companies, since it’s generally too toxic to simply be poured out on the ground — although the state allows drillers to spread produced water on roads if it meets a purity standard. Some of the flowback fluid can be put through filters and reused at the next well.