The recent US shale boom has spurred economic growth but it has also generated a public debate about whether the hydraulic fracturing methods of extracting the fossil fuels cause water, air, or other environmental degradation. This week, the Proceedings of the National Academy of Sciences released a study linking the contamination of water wells to the faulty construction of nearby gas wells rather than the drilling or fracking mechanisms of releasing gas from shale formations. The peer reviewed study analyzed data from 133 contaminated drinking water wells in Pennsylvania and Texas which fall in the Marcellus shale and Barnett shale. Water wells were sampled to identify the source of gas contamination and if increased levels of gases in drinking water wells occurred naturally or whether the change in water quality was caused by fracking.
The findings rule out the notion that gas contamination migrated upward through overlying geological strata during horizontal drilling or hydraulic fracturing and instead point to faulty well casings and cement failures as the source of water well contamination. In linking tainted water wells to the construction and integrity of nearby gas wells, perhaps we will see the public shift focus to improving the state of well integrity regulations to better protect the environment.
Last year in Texas the Railroad Commission overhauled state well integrity rules to ensure oil and gas wells are constructed with transparency and the latest technology. Starting in January of this year, the new rules have been in effect. But, the new well integrity rule hasn’t satisfied homeowners who connect the nearby production of hydraulic fracturing to the contamination of their drinking water wells. In Denton, Texas, the November 4 ballot will ask voters to decide whether the practice of hydraulic fracturing should be banned within the city limits.