Unused underground storage tanks should never be left or forgotten. If the tank leaks, any contents left inside the tank could seep into the surrounding soil. This exposes the landowner to significant environmental liability. Removing the tank is the better alternative.
Federal and state regulators have strict requirements for the removal of underground storage tanks. These rules are to prevent accidental spills or contamination. Hiring a professional to handle the removal minimizes these risks.
Before you hire anyone, it’s important to understand the process for removing tanks.
Steps Taken During a Typical Underground Storage Tank Removal
#1 Notify Government Agencies of Removal
Before you can remove an underground storage tank, you need to notify federal and state agencies at least 30 days prior to the work. You may also need special permits at the county or city level.
#2 Hire a Licensed Contractor
Look for a contractor with experience removing such tanks. Many states require the contractor to hold a special certification or license to perform the work. A licensed contractor will pull the proper permits and follow the rules for safe tank removal.
#3 Remove Remaining Material from Tank
Almost all tanks have some reside remaining inside. Before anything can be done with the tank, the contents must be removed. The contractor must follow strict protocols, especially with flammable or toxic substances.
#4 Displace Oxygen in Tank
Oxygen inside the tank can, in some cases, have the potential to cause an explosion. Before the tank can excavated and removed, the air inside the tank must be inert. This involves removing the oxygen and replacing it with a non-explosive gas like carbon dioxide or nitrogen.
#5 Remove Soil Around Tank
The contractor will remove the soil around the top of the tank first, exposing the fittings and lines. These need to be removed before digging out the rest of the tank.
#6 Clean and Remove Tank
Some jurisdictions require the tank be cleaned of contamination before it’s removed from the job site. Others allow for tank removal to a secondary location for cleaning. In either case, the contractor will clean the tank and remove it.
#7 Prepare for Tank Disposal
Once the tank it out of the ground and cleaned, the contractor must follow strict guidelines for disposal. Some jurisdictions allow for cutting the tank up on site, while others allow it to be moved intact. The contractor will identify safety hazards, mitigate vapor, dispose of residue, and clean the system.
#8 Perform Required Sampling
After the tank is gone, the state requires the contractor to take samples from the surrounding soil. It’s to identify whether contaminants have leaked. In some cases, the state may require samples of groundwater as well.
#9 Remove and Dispose of Contaminated Soil
If contaminated soil is found, it must be removed. The contractor will remove it and dispose of it according to federal and state requirements.
#10 Report Results to Appropriate Agencies
Once the work is done and the samples taken, the contractor must report the results to the appropriate agencies. A typical report documents the following:
- Results of soil and groundwater sampling
- Map of where samples were taken
- Documentation of underground storage tank disposal
- Documentation of soil removal
#11 Filling In the Hole
The last step is to fill in the hole left after the storage tank removal. Any uncontaminated soil from the initial excavation can be used. Off-site soil can also be used to fill it in.
Removing abandoned underground storage tanks reduces the risk of environmental contamination. It also enhances the property value because buyers don’t have to deal with the issue. The sale can go through without the need for expensive investigation and remediation.
If you have an unused underground storage tank, talk with a specialist before you do anything. Learn what your options are and make an informed decision.