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An Introduction to Leaking Underground Storage Tanks

An Introduction to Leaking Underground Storage Tanks

Leaking underground storage tanks (USTs) are a significant source of environmental contamination and may pose the following threats to human health and safety:

  • fire and explosion;
  • inhalation of dangerous vapors;
  • contamination of soil and groundwater;
  • contamination of drinking water; and/or,
  • contamination of streams, rivers, and lakes.

Underground storage tank upgrade

These threats are minimized when responsible parties respond quickly and efficiently after an UST release. State agencies and environmental consultants are ready to assist UST owners and operators in responding to leaking USTs.

Agencies that Deal with USTs and Leaking USTs

The Illinois Office of the State Fire Marshal (OSFM) regulates the daily operation and maintenance of UST systems. If a release occurs, tank owners or operators, or their designated representatives, must notify the Illinois Emergency Management Agency(IEMA), which then notifies the Illinois Environmental Protection Agency (Illinois EPA). The Illinois EPA's Leaking Underground Storage Tank Section begins oversight of remedial activities only after the UST release has been reported to the IEMA.

OSFM is authorized to:

  • Certify tank installation and removal contractors.

  • Monitor compliance regarding leak prevention and detection requirements.

  • Issue permits for tank installations, repairs, upgrades, closures, and removals.

  • Administer financial responsibility requirements.

  • Determine whether tank owners and operators meet eligibility requirements and, if so, the appropriate deductible amount for payment from the UST Fund.

  • Order tank owners or operators to remove the USTs and perform initial abatement measures when UST releases threaten human health or the environment.

Illinois EPA is authorized to:

  • Review and evaluate technical plans and reports to determine if tank owners or operators are complying with environmental laws and regulations governing leaking UST site investigations and cleanups.

  • Require tank owners or operators to perform corrective action when UST releases threaten human health or the environment.

  • Review and evaluate tank owners' and operators' budgets and claims for payment from the UST Fund.

  • Issue No Further Remediation (NFR) Letters to tank owners or operators once the Leaking UST Program requirements and cleanup objectives have been met.

Act Immediately if You Suspect a Tank Release

If a release has not been confirmed but you believe free product (petroleum not dissolved in water) or product vapors pose a serious threat, take the following steps as appropriate:

  • Extinguish all smoking materials or open flames that could ignite explosive vapors.

  • Call the local fire department.

  • Take care not to activate electrical switches or equipment that could cause sparks and ignite explosive vapors.

  • Evacuate the area.

  • Follow the environmental regulations, as required of tank owners or operators or their designated representatives, including:

    • Call IEMA immediately whenever a release causes a sheen on nearby surface waters, or

    • Call IEMA within 24 hours of any other release, and

    • Stop the leak and contain the spill.

Drums of gasoline-contaminated water

IEMA maintains a 24-hour hotline. In Illinois, call 800-782-7860. Out of state, call 217-782-7860.

Environmental Consultants Offer Technical Expertise

Environmental consultants, including removal contractors and professional engineers and professional geologists, offer many services to help you handle your UST release in a timely and efficient manner. You will find consultants listed in the Yellow Pages of your local phone book or by searching online for local services. Illinois EPA does not endorse or recommend consultants. Before signing a contract, make sure the consultant can perform the following activities:

  • Determine the appropriate regulations to which a particular incident is subject, and conduct remediation and/or pursue closure accordingly.

  • Conduct a site investigation to determine if remedial actions are required.

  • Follow proper sample collection protocols to assure valid and reliable results. (Deviations may result in additional sampling and expense.)

  • Assure that laboratory samples are analyzed according to proper methods and procedures by an accredited laboratory to avoid costly retesting.

  • Interpret laboratory results and organize this data into reports for review by the Illinois EPA's Leaking UST Section.

  • Provide equipment and personnel to conduct the required remedial activities or hire subcontractors to perform such work.

  • Arrange for safe and proper handling of contaminated soil and groundwater.

  • Evaluate cost and liability factors resulting from interim measures, as well as from final disposal or treatment options, for contaminated soil and groundwater.

  • Obtain all necessary manifests and permits before moving or disposing of contaminated materials.

  • Prepare reports and provide certifications by Licensed Professional Engineers or Licensed Professional Geologists as required by environmental laws and regulations.

  • Prepare budgets and submit claims for payment from the UST Fund. An Illinois Licensed Professional Engineer or Licensed Professional Geologist must certify that all regulatory requirements have been met before any budgets or claims can be reviewed. Illinois EPA will not authorize payment of ineligible or unreasonable costs, costs from work that deviates from approved plans, or costs for site investigation or corrective action activities that exceed the minimum requirements stated in the environmental laws and regulations.

Tank Owner or Operator Requirements

Owners or operators required to report leaking UST releases to IEMA must also meet the requirements of the Illinois Environmental Protection Act and 35 Illinois Administrative Code Part 731 or 734. Once notified of the release by IEMA, the Leaking UST Section mails a letter requiring compliance with Leaking UST Program regulations and the submittal of applicable technical forms.

Tiered Approach to Corrective Action Objectives (TACO)

Based on Site Conditions and Exposure Risks

Sampling groundwater

TACO is Illinois EPA's method for developing cleanup objectives for contaminated soil and groundwater. These cleanup objectives protect human health while taking into account site conditions and land use.

TACO offers tank owners and operators the following choices:

  • Exclusion of exposure routes (inhalation, soil ingestion, and groundwater ingestion);

  • Use of area background concentrations as screening tools or remediation objectives; and,

  • Three tiers for selecting remediation objectives.

In Tier 1, the tank owner or operator compares site sample analytical results to baseline cleanup objectives contained in "look-up" tables. Under Tier 2, a tank owner or operator considers data previously gathered for Tier 1, the physical and chemical properties of the contaminants, the site-specific soil and groundwater parameters, and the application of institutional controls and engineered barriers. Tank owners and operators can use Tier 3 for sites where physical barriers limit remediation, a full-scale risk assessment is performed, alternative mathematical modeling is applied, or a common-sense solution is warranted.

After establishing cleanup objectives under TACO, a tank owner or operator may:

  • Reduce contaminant concentrations to meet the established objectives through active remediation (e.g., dig and haul or treatment in place);

  • Restrict exposure to contaminated soil or groundwater or both by using engineered barriers or institutional controls;

  • Take no action, if contaminant concentrations present at the site do not exceed remediation objectives; or,

  • Use any combination of the options above.

An engineered barrier, such as asphalt paving, clean soil, or a permanent structure, controls migration of and access to contamination. An institutional control imposes restrictions and conditions on land use. For example, a tank owner or operator may choose to limit the site to industrial/commercial use. When the property owner and the tank owner or operator are separate entities, the property owner must agree to any type of proposed land use limitation.

A leaking UST site qualifies to receive an NFR Letter once the tank owner or operator meets all Leaking UST Program requirements and the applicable TACO cleanup objectives. Within 45 days, the tank owner or operator must file the NFR Letter with the county recorder of the county in which the site is located to ensure that current and future users of the property will be informed of any conditions such as engineered barriers and institutional controls that were relied upon to address contamination caused by an UST release.

Where to Direct Your UST and Leaking UST Questions

If you have questions concerning permits required for tank installations, upgrades or removals; leak prevention or detection requirements; financial responsibility requirements; or eligibility and deductible determinations for the UST Fund, contact:

Office of the State Fire Marshal
Division of Petroleum and Chemical Safety
1035 Stevenson Drive
Springfield, Illinois 62703

If you have questions concerning the review of budget plans and technical reports, or the status of applications for payment from the UST Fund, contact:

Illinois Environmental Protection Agency
Leaking Underground Storage Tank Section
1021 North Grand Avenue East
P.O. Box 19276
Springfield, Illinois 62794-9276

This publication is for general information only and is not intended to replace, interpret, or modify laws, rules, or regulations.

Last Updated: April 2022