Injection wells are used to dispose waste into the subsurface zone. These wastes can include brine from oil and gas wells, liquid hazardous wastes, agricultural and urban runoff, municipal sewage, and return water from air-conditioning. Recharge wells can also be used for injecting fluids to enhance oil recovery, injecting treated water for artificial aquifer recharge, or enhancing a pump-and-treat system. If the wells are poorly designed or constructed, or if the local geology is not sufficiently studied, injected liquids can enter an aquifer and cause groundwater contamination. Injection wells are regulated under the Underground Injection Control Program of the Safe Drinking Water Act.

See Also

Aquifer Restoration; Deep-Well Injection; Drinking-Water Supply; Groundwater Monitoring; Groundwater Pollution; Water Table