What type of wells can lead to water supply contamination?

Injection wells are a type of well specifically designed to introduce fluids into the ground, typically for purposes such as wastewater disposal or the injection of chemicals. Because these wells are utilized to dispose of various liquids, including potentially hazardous substances, there is a significant risk that they could lead to water supply contamination if not properly managed. The fluids injected may migrate through the surrounding soil and rock formations, especially if there are pathways such as fractures or poorly sealed well casings, thus impacting underground sources of drinking water.

On the other hand, test wells and monitoring wells primarily serve to assess water quality and monitor groundwater levels, so they are not typically associated with contamination risks in the same way. Artisanal wells, often hand-dug and used for domestic water supply, can have quality issues due to their construction and location; however, they are not designed for introducing potentially contaminated fluids into the ground. Thus, the characteristics and purpose of injection wells make them a primary concern for potential water supply contamination.