There are six different classes of wells. These classes were set by the EPA and are categorized based on the materials utilized in injections.
Class I wells inject hazardous wastes, industrial non-hazardous liquids, and municipal wastewater.
Class II wells inject brines, hydrocarbons, and various fluids associated with oil and gas production.
Class III wells inject fluids associated with the solution mining of minerals.
Class IV wells utilize hazardous or radioactive wastes. These are typically banned unless authorized under a federal water remediation project.
Class V wells include all other wells not previously mentioned, including experimental wells. Nonhazardous fluids are used and these wells have shallow, on-site disposal systems.
Class VI wells are used for geologic sequestration of carbon dioxide.
Based on the class of well, different regulations are applied to the site. Typically, wells in Pennsylvania are Class II wells. The more specific information regarding the wells’ classifications in Tioga County is restricted.
Literature Cited
Schultz, A. (2012). Hydraulic Fracturing and Natural Gas Drilling. Nova Science Publishers.