Tuesday November 10, 2015 0 comments
FORT COLLINS -- Studies conducted at Colorado State University indicate there’s no evidence of water-based contaminants seeping into drinking water wells in northeastern Colorado in the 6,700 square-mile Denver-Julesburg oil-and-gas basin.
The studies were performed under Colorado Water Watch, a state-funded effort begun last year for real-time monitoring of the D-J Basin. The CSU study primarily looked at 24,000 producing and 7,500 abandoned wells in the Wattenberg Field, which lies mainly in Weld County.
“There isn’t a chronic, the-sky-is-falling type of problem with water contamination,” said Ken Carlson, professor of civil and environmental engineering who led the studies.
Carlson’s team did find 2 percent of their sampled wells showed seepage of oil-and-gas-related methane, a flammable but nontoxic greenhouse gas that is the main component of natural gas.
But Carlson’s team did not find any toxic contaminants such as barium or chromium in their studies.
The CSU studies strengthen the theory that methane contamination is most likely due to stray gas along the outside of compromised well casings in and around aquifers.
“My guess is that most of the thermogenic methane-contaminated wells we see out there are 10 to 30 years old,” Carlson said. “Well casing requirements and monitoring have tightened up significantly since the 2009 regulations.”
The CSU studies are published in Environmental Science and Technology and in Water Research.