Studies by the Ground Water Protection Council (GWPC), an association of state regulators, and the Environmental Protection Agency (EPA) have clearly demonstrated the effectiveness of current state regulations in protecting water resources. When the GWPC studied the environmental risk of hydraulic fracturing, they found one complaint in the more than 10,000 coalbed methane wells reviewed – an Alabama well where problems were not related to fracturing according to the EPA. The EPA initiated its own study of environmental risks from coalbed methane hydraulic fracturing and, again, no significant environmental risks as a result of proper hydraulic fracturing were identified.
The key word in the preceding sentence, of course, is proper. Although there is some variability in the details of well construction because of varying geologic, environmental, and operational settings, the basic practices in constructing a reliable well are similar. These practices are the result of operators gaining knowledge based on years of experience and technology development and improvement.
The ultimate goal of the well design is to ensure environmentally sound and safe production of oil and/or natural gas by containing them inside the well, protecting groundwater resources, isolating the productive formations from other formations, and by proper execution of hydraulic fractures and other stimulation operations. The primary method used for protecting groundwater during drilling operations consists of drilling the wellbore through the groundwater aquifers, immediately installing a steel pipe (called casing), and cementing this steel pipe into place.
In addition to Federal rules, statutes and regulations have been implemented in every oil and natural gas producing state to ensure that operations are conducted in an environmentally responsible fashion. All state drilling regulations specifically address groundwater protection, including requirements for the surface casing to be set below the lowest groundwater aquifer. This casing in combination with other steel casing and cement sheaths that are subsequently installed protects the groundwater with multiple layers of protection for the life of the well. Additional protection is offered by the impermeable rock formations that lie between the oil and natural gas formations and the groundwater, formations that have isolated the groundwater over millions of years.