PLUGGING ABANDONED WATER WELLS

Introduction

• Abandoned water wells as a risk to our:– Safety– Water supply

• How can we plug these abandoned wells.

Introduction

• Have you seen an abandoned well?• If so what was the condition of the well.

– Was it covered?– How easy would it have been to fall in?

Well Plugging Video

• This video was created through a joint effort by the Texas Cooperative Extension and the Texas Groundwater Protection Committee.

Why are Wells a Treat?

• Open hole that a person can fall into and be injured.

• Provide a direct conduit for surface water to be carried down t the groundwater resource.

• Provide a means for the groundwater from two different aquifers t be mixed.

Abandoned Well?

• If the well is not considered in use for six months.

• A well is considered in use if it:– has a good casing, pump and pump column.– has a non-deteriorated well casing that has

been capped.

Plugging Materials

• Bentonite clay.– Chips and Slurry

• Cement slurry.• Hand dug wells can be filled with a good clay soil or

caliche soil.

Key Steps to Plug an Abandoned Well

1. Measure the dimensions of the well.

2. Remove all obstructions from the well.

3. Disinfect the well by adding household bleach.

4. Remove as much casing as possible.

5. Fill the well with plugging materials.

6. Complete the plugging report.

Step One

• Measure the dimensions of the well.– Determine the volume of plugging material needed to

plug the well – Determine the quantity of standing water in the well.

Step Two

• Remove all obstructions from the well.– Prevent plugging materials from reaching the

bottom of the well.– Potential for future settling an disturbance of

seal.

Step Three

• Disinfect the well by adding household bleach.– Kills any microorganisms in the well water.– Prevents sealing of microorganisms in the aquifer.

Step Four

• Remove as much casing as possible.– Removes direct conduit to the groundwater.– Removes annular space around well.– Allows native soil to bond with plugging materials.

Step Five

• Fill the well with plugging materials.– Restrict water movement from the soil surface to the

groundwater. These materials need to be clean to prevent contamination of the groundwater and prevent bridging as the materials enter the well.

Step Six

• Complete the plugging report.

– The plugging report provides documentation that the well has been properly plugged. This material needs to be sent to the Texas Department of Licensing and Regulation and local groundwater districts.

Conclusion

• Abandoned wells are a danger for falling into the well provide a direct conduit for contaminants to reach groundwater.

• A well is considered abandoned if it is not used for six months and has a deteriorated casing, or inoperable.

• The well will not be considered abandoned if it is capped, returned to an operable status or is plugged.

Conclusion

• To properly plug an abandoned well you need to fallow the six key steps in the plugging process.