From The Pueblo Chieftain (Chris Woodka):
The amount of water required per oil well can vary from 1 million to 8 million gallons, depending on where the well is. That’s a one-time use over the life of the well. In a vertical well, fracking may occur only once. In a horizontal well, it can be done up to 40 times. “The most we’ve seen in Colorado is a dozen,” Kerr said.
Of more concern are the chemicals used in fracking, which can affect water quality. About half of the drillers voluntarily provide the state with information about which chemicals are being used. Next month, the commission will have rule-making hearings that include a requirement to divulge the chemicals used.
The state already requires concrete casing of oil wells to a depth of 50 feet below the deepest aquifer. The Niobrara is 8,000 feet under the Denver Basin. Water wells in the area are 500 to 2,000 feet deep. State rules also require isolating the fracking zones to prevent migration of chemicals into water supplies.
State Rep. Marsha Looper, R-Calhan, plans to introduce legislation that would require a more complete state accounting of the water needs of oil and gas drilling in the state.
More 2012 Colorado legislation coverage here.