A casing is placed down the drilled hole to access the groundwater below. A functioning water well serves as a channel for bringing groundwater to the surface. An abandoned well, likewise, serves as funnel for carrying contaminants from the surface to the groundwater below. A water well also may pass through two different aquifers and have a deteriorated well casing that allows water from two different aquifers to mix. A well casing can develop a hole in the elevation of the upper aquifer and allow the water from the upper aquifer to flow down the casing to the lower aquifer and contaminate it.
Some wells pose a considerable danger to people, wildlife and the environment.
Some landowners may be able to do the job themselves. In some cases, it is recommended that a licensed water well driller or pump installer is hired to seal and plug an abandoned well. Landowners who plan to do the work themselves must first contact the Water Well Drillers Program of the Texas Department of Licensing and Regulation with their intent and method they plan to use. They also should request a state well plugging form. Within 30 days of plugging the well, they must send a copy of the form to the TDLR and a copy to their local groundwater district, if one is present.