Underground Tank Closure in Place
Underground storage tank closure in place involves more than just filling the underground storage tank (UST) with a solid, inert material. The service cost of a tank closure in place is more than a typical underground tank removal service. To help property owners understand the process of a tank closure in place, the information below details the steps required by most towns in Massachusetts and New Hampshire. Our CommTank team of people also have the expertise and experience to answer your questions about UST closure in place.

Excavating to the top of a buried underground tank.
- An area permit application must be submitted and approved by the Fire Department to close the underground tank in place.
A tank systems inspector must perform a closure assessment, which includes a visual inspection.
The fire department may require a structural engineer to inspect the site.
A home or commercial tank system must be pumped of fuel and transferred to a truck and fumes inside the tank must be evacuated.
Ground soil areas must be excavated and the tank must be cut open for the crews to climb inside and remove the tank bottom sludge.
If the tank is not easily accessible, then soil borings on two sides of the tank must be taken to ensure the soil surrounding the tank is clean.
One or more soil samples must be collected from under the tank and sent to a lab for analysis. All closure assessment reports and the UST closure notices are created using data from the lab samples.
Water monitoring wells must be installed when ground water is present, in order to obtain accurate water samples.
Fill the fuel storage container with flowable fill (an economical alternative to sand or gravel which require compacting).
Provide a closure report including field notes, and lab report.
Cost Comparison of an Underground Tank Closure in Place Versus Tank Removal

1,000-gallon underground oil tank is buried in this front yard.
The information below is a typical amount of price range for a UST closure in place versus a UST removal for a 1,000-gallon underground fuel storage tank.
- Cost range of a UST Closure in Place: $4,000 - $5,000
- Cost range of a UST Removal: $2,500 - $3,500
A cost range is provided instead of a fixed price due to the variables involved with both project types. Property areas such as home foundations, porches, decks, and patios often require support or restoration when servicing a buried fuel storage container. Area utilities such as gas, electric, or sewer piping may require hand digging or temporary disconnection. Use of a saw may be necessary to cut concrete or asphalt and remove it when the tank is buried under the foundation and driveway. The tank contractor’s approach to preserving or replacing trees, shrubs, and grass and how experienced they are at protecting these landscapes can separate a professional contractor from a low-cost service provider.

An oil tank was found buried beneath this kitchen floor. This Haverhill Massachusetts house was built on a slab foundation.
Our team recommends removing an underground fuel storage container. When structural issues are a concern, the building or wall can be supported during the removal process. Large tanks can be cut into smaller sections while the surrounding soil is supported and removed a section at a time. UST removal is generally recommended whenever possible to avoid future problems or questions concerning the fuel storage container.
Sometimes a structural engineer will recommend closing a UST in place if removal would cause foundation damage. This is a service that CommTank can provide. The regulations for taking a buried fuel storage container out of service in Massachusetts and New Hampshire are listed below.
In-place Closure of Tanks in Massachusetts

The Reading Fire Department approved an underground tank closure because the tank is buried next to a pool.
Massachusetts regulations allow the local fire department to determine if an underground tank used for fuel storage can be closed in place. If use was for water storage and the removal will jeopardize a building or another UST in use, then it may be closed in place if approved by the fire department. (Board of Fire Regulations 527 CMR 9.07(J))
Tank Closures in Place for New Hampshire
The State does not regulate home use (residential) underground tanks, but the New Hampshire Department of Environmental Services (DES) asks that the owner/consultant/contractor contact DES to get approval for closure in place. Upon request, they will review their records and determine whether a closure in place is possible.
For regulated underground tanks (tanks deemed not for consumptive use), New Hampshire regulations require notification of the DES at least 30 days prior to any scheduled UST system permanent closure. If removal of UST systems would serve to undermine the integrity of an overlying structure(s), or compromise the structural integrity of an adjacent underground storage tank system, then the underground storage tank system may be permanently closed in place. Please keep in mind that all other requirements for closure in Env-Or 408.05 through 408.10 shall be complied with, including, but not limited to: notification prior to closure, ICC-U2 licensed supervision during all closure activity and submittal of closure report.
(Code of Administrative Rules Env-Or 408.07, Procedures for Permanent Closure)