Underground injection wells

Underground Injection Wells
Steel- and concrete-encased shafts into which hazardous waste is deposited by force and under pressure.
Underground Sources of Drinking Water ...

Underground Injection Wells
Underground Sources of Drinking Water
Underground Storage Tank (UST)
Unreasonable Risk
Unsaturated Zone
Upper Detection Limit
Uranium Mill Tailings Piles
Uranium Mill-Tailings Waste Piles
Urban Runoff ...

See also: Aquifer, Injection well, Ultraviolet rays, Uncertainty factor, Unconfined aquifer