Frequently Asked Questions
Where are the Marcellus and Utica Shale deposits?
Together, the Marcellus and Utica Shale regions extend across New York, Pennsylvania, Maryland, West Virginia, Ohio and portions of Kentucky and Tennessee.
How is drilling in the Marcellus and Utica Shales regulated by ODNR and Ohio EPA?
The Ohio Department of Natural Resources, Division of Oil and Gas Resources Management (ODNR-DOGRM) has primary regulatory authority over oil and gas drilling activity in Ohio, including regulations for well construction, siting, design and operation. ODNR-DOGRM regulates disposal of brine and drilling fluids from oil and gas drilling/production. ODNR-DOGRM regulates Class II underground injection wells used for disposal of waste fluids from oil and gas drilling/production operations and transporters hauling these fluids in Ohio.
Ohio EPA’s water quality certification requirements address impacts to wetlands, streams, rivers or other waters of the state from the construction of a drill site. Ohio EPA also regulates sources of air emissions and may require air permits for equipment at the drill site once a well goes into production. Ohio EPA also requires proper management for any solid waste sent off-site for disposal.
How is natural gas extracted from a shale formation?
Natural gas is extracted from the shale through a two-step process of horizontal drilling and hydraulic fracturing. To start, a production well is drilled thousands of feet downward and then gradually angled out horizontally through the shale deposit. The well is drilled horizontally to maximize the ability to capture natural gas once the shale is hydraulically fractured.
After the well is drilled, a mixture of water, sand and chemical additives is injected at very high pressure to fracture the shale. This part of the process, called hydraulic fracturing, is a technique used in the oil and gas industry since the 1950s. The sand keeps the fractured shale open and serves as a conduit for extracting the natural gas. The chemical additives reduce potential problems during drilling and gas production, such as bacterial build-up and the formation of scale, mineral deposits and rust.
How much water does it take to hydraulically fracture a well?
It can take up to four million gallons of fresh water to fracture a single well. The water used in the fracturing process usually comes from a stream, river, reservoir or lake near the drill site, or in some cases, from a local municipal water plant.
What happens to water after hydraulic fracturing is complete?
Most of the water used to fracture the shale remains trapped thousands of feet underground after it is injected. However, internal pressure in the geologic formation forces some of the water (around 15-20 percent of the total volume injected) back to the surface through the well bore.
Most of this flowback water comes back to the surface within seven to ten days after it is injected. Flowback water is stored temporarily in tanks before being sent off-site for disposal. Drilling companies are required to send brine and flowback water to disposal facilities that have permits to inject fluids thousands of feet underground into deep injection wells (called Class II wells).