What to Know About Tank Decommissioning & Closure in Illinois
Three state bodies share underground storage tank work in Illinois. The Office of the State Fire Marshal (OSFM) regulates tanks and issues the permits for tank removal and abandonment in place. IEMA takes release reports, and Illinois EPA (IEPA) oversees cleanup through its Leaking Underground Storage Tank program. The UST definition in 41 Ill. Adm. Code 174.100 leaves out a heating oil tank of any capacity used only to heat a farm or residence, so a home heating oil tank is not a UST in Illinois. Farm and residential motor fuel tanks of 1,100 gallons or less used for noncommercial purposes are also excluded. A heating oil tank at a business is different: it stays a UST and needs an OSFM permit to be removed or abandoned in place.
Tank closure for a regulated UST begins with an OSFM permit. 41 Ill. Adm. Code 175.300 requires the application and a $200 fee per permitted activity before the work starts, and OSFM issues permits only to contractors it has licensed. OSFM's frequently asked questions answer "No" to whether an owner may do the tank work personally, and require one ICC-certified person on the job site at all times. An OSFM Storage Tank Safety Specialist must be on site before any tanks or piping come out. Soil samples are taken in native soil while the excavation is still open, under a licensed professional engineer or geologist. Within 45 days of receiving the lab results, the owner submits the Site Assessment Results form to OSFM. When no release is confirmed, the owner certifies to OSFM that the removal or abandonment met the rules, and under 415 ILCS 5/57.5(f) OSFM then issues a certificate of removal or abandonment.
Today the Illinois UST Fund pays for cleanup after a reported release, not for a planned tank removal. From January 1, 2027, Public Act 104-688 (415 ILCS 5/57.9(a-5)) also lets the fund pay eligible costs of removing a UST installed before January 1, 1976. Illinois EPA must approve a tank removal plan and budget before the removal, and a $5,000 deductible applies. OSFM decides whether an owner is eligible and sets the deductible, and Illinois EPA reviews and pays claims. Under the IEPA Fund Guide, the deductible is $5,000 for releases reported on or after June 8, 2010. IEPA's LUST page lists a maximum of $1,500,000 per occurrence, minus the deductible. The guide also requires that the UST not be a farm or residential heating oil tank. The LUST page also states that the fund will not pay for planned tank removal, tank upgrade costs, or work performed before the petroleum release was reported. Our guide to closure in place versus UST removal explains what changes the scope of a job.
In Chicago, the city's Department of Environment issues the UST permit. Its page says a DOE permit must be obtained first to install, upgrade, repair, remove or abandon a UST in the city. Contractors apply through the OSFM Contractor Portal and must give DOE written notice at least 30 days before a planned removal. If a release shows up during a tank closure, the owner must report it to IEMA immediately (41 Ill. Adm. Code 176.320), and when the Storage Tank Safety Specialist sees evidence of a release, the call is made from the site before the specialist leaves. OSFM's contractor search can be filtered by county and by the Decommissioning license module. Before hiring any contractor on this page for a regulated UST, confirm the company holds that module.