COLLEGE STATION – An estimated 150,000 abandoned water wells exist in Texas, and each one poses a threat to water safety, said Bruce Lesikar, Texas Cooperative Extension agricultural engineer.

"An abandoned well is a direct channel from the surface to the aquifer below," Lesikar said. "Contaminants that enter a well are introduced directly into the aquifer with no opportunity for natural filtration by soils or geologic materials."

If the abandoned well is uncapped, a contaminant can easily enter and potentially pollute the underlying aquifer.

“Plugging abandoned wells is not just a smart move to keep water safe, but it's also the law, said Monty Dozier of College Station, Extension soil scientist. “Texas law holds landowners responsible for plugging abandoned wells and for any contamination or injury the well caused.

"Abandoned water wells need to be properly closed. A well is considered abandoned if it has not been used for six consecutive months.”

“In some cases, landowners can close the well themselves. Landowners can generally plug both water wells with less than 100 feet of standing water, and large diameter, hand-dug wells,” Lesikar added. “But before any work is done, they need to contact the Water Well Drillers Program of the Texas Department of Licensing and Regulation and get a plugging method approved, he said. A well plugging report must be completed and filed with the Texas Department of Licensing and Regulation and the local Groundwater Conservation District.”

To plug the well, the dimensions are taken, debris is removed, and the well is disinfected with bleach. Some of the outside casing is removed, and the well is properly filled. The last step is completing the well lugging report. Filing this report is critical to documenting the proper closure of the water well.

Wells can be filled using bentonite chips (an absorbent aluminum silicate clay), cement slurry, clay or caliche soil, Lesikar said.

If well type or depth requires a professional to fill the well, or if the job is too much to handle, a licensed well driller and pump installer can legally fill wells according to code.”

Water is one of Texas' most valuable resources, Lesikar said. “A clean supply allows citizens to enjoy a constant food supply, sanitation, recreation and everyday leisure. It provides employment for hundreds of thousands of Texans and helps keep families safe from disease. Once a water resource is contaminated, it requires additional resources to remove the contaminants. Therefore the job of protecting it goes to all Texans,” he said.

Further information about plugging abandoned wells is available by contacting an Extension agent, local groundwater conservation district or the Texas Department of Licensing and Regulation at (512) 463-7880.