Underground Tank Closure in Place
Closing an underground storage tank in place involves more than just filling the underground tank with a solid, inert material. The cost of a tank closure in place is typically more than that of an underground tank removal service. To help you understand what is involved for a tank closure in place, the following are a list of required steps by most towns in Massachusetts and New Hampshire.
- An application for a permit must be submitted and approved by the Fire Department to close the underground tank in place.
- A tank inspector must perform a closure assessment, which includes a visual inspection.
- The fire department may require a structural engineer to inspect the site.
- The tank must be pumped of fuel and transferred to a truck and fumes inside the tank must be evacuated.
- The ground needs to be excavated and the tank has to be cut open for the crews to climb inside and remove the tank bottom sludge.
- If the tank were not easily accessible then soil borings on two sides of the tank must be taken to ensure the soil surrounding the tank is clean.
- A soil sample must be collected from under the tank and sent to a lab for analysis. The closure assessment report and the UST closure notice are created utilizing the data from the lab samples.
- When groundwater is present, monitoring wells need to be installed to take accurate water samples.
- Fill the tank with flowable fill.
- Provide a tank closure report including field notes, and lab report.
Cost Comparison of an Underground Tank Closure in Place Versus Tank Removal
The following is a price range for a tank closure in place versus an underground tank 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. Foundations, porches, decks, and patios often require support or restoration when servicing a buried oil tank. There may be utilities in the area such as gas, electric, or sewer piping that require hand digging or temporary disconnection. It is necessary to saw cut concrete or asphalt and remove it when the tank is buried under the foundation and driveway. The underground tank contractor’s approach to preserving or replacing trees, shrubs, and grass and how experienced they are at protecting these landscapes can separate the professional contractor and a low-cost service provider.
We recommend having an underground tank removed. When structural issues are a concern, the building or wall can be supported during the removal process. A large tank can be cut into smaller sections while the surrounding soil is supported and removed a section at a time. Underground tank removal is generally recommended whenever possible to avoid future problems or questions concerning the underground storage tank.
If a structural engineer recommends closing an underground in place because removing the tank would cause foundation damage, CommTank can provide this service for you. The regulations for taking a buried tank out of service in Massachusetts and New Hampshire are listed below.
Tank Closures in Place for Massachusetts
Massachusetts’s regulations allow the local fire department to determine if an underground tank used for fuel storage can be closed in place. If a tank was used for water storage and the removal
will jeopardize a building or another underground storage tank (UST) in use, then the tank may also 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 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 not for consumptive use), New Hampshire regulations require notification of the DES at least 30 days prior to any scheduled underground storage tank system permanent closure. If removal of an underground storage tank system 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.