RESPONDING TO A RELEASE FROM YOUR MUNICIPAL UNDERGROUND STORAGE TANK

You have just been informed that your underground storage tank system has been acting erratically and that there appears to be a sudden loss of product from the tank and/or an unexplained presence of water in the system. You suspect that a leak has occurred but you are hesitant to investigate further knowing that confirmation of the same will certainly trigger some kind of notification requirement under the existing rules and regulations. Too late. Subject to some limited exceptions, if a release from an underground storage tank is either detected or suspected, the owner/operator of the tank must notify the Illinois Emergency Services and Disaster Agency (IESDA) within 24 hours of the release or suspected release. Immediate notification to IESDA, the National Response Center, and to a local emergency agency is required when gasoline or other fuel with a flash point of less than 140 degrees fahrenheit is released in a quantity greater than 12.5 gallons (i.e., overfills and spills) or when an oil sheen occurs on surface water bodies.

In addition, when required by the Fire Marshal, owners and operators of underground storage tanks must undertake release investigation and confirmation procedures to determine if the underground storage tank system is the source of off-site impacts. These impacts include the discovery of a regulated substance that has been observed by the Fire Marshal or brought to its attention by a third person.

According to both Federal and Illinois regulations, observation of unusual operating conditions, including the erratic behavior of product dispensing equipment, the sudden loss of product from an underground storage tank, or an unexplained presence of water in a tank, requires a tank owner and/or operator to inform the appropriate agencies of a suspected release, unless the system equipment is found to be defective but not leaking, and is immediately repaired or replaced. Other conditions that require notification is the discovery of released regulated substances at the underground storage tank site or in the surrounding area (such as the presence of free product or vapors in soils, basements, sewer and utility lines and nearby surface water) or there is an indication of a leak from the monitoring results of a leak detection method required under the regulations. However, if the monitoring device is found to be defective and is immediately repaired, recalibrated or replaced, and additional monitoring does not confirm the initial release, the owner/operator is not required to notify IESDA. Furthermore, in the case of inventory control, if the records show a loss of product for one month and a second month of data does not confirm the initial loss of product, the owner/operator is not required to notify IESDA.

After reporting the release to the appropriate agencies, the owner/operator has seven days to investigate and confirm the suspected release by performing a tightness test and a site check. If a release is confirmed at any time, the owner/operator must perform the following initial response actions within 24 hours of a release:

(a) Report the confirmed release to the appropriate agencies;

(b) Take immediate action to prevent any further release of the regulated substance into the environment;

(c) Identity and mitigate fire, explosion and vapor hazards. Unless directed to do otherwise, owner/operator must also perform the following initial abatement measures:

(1) Remove as much of the regulated substance from the underground storage tank system as is necessary to prevent further release into the environment;

(2) Visibly inspect any above-ground releases or exposed below-ground releases and prevent further migration of the release substance into the surrounding soils and groundwater;

(3) Continue to monitor and mitigate any additional fire and safety hazards posed by vapors or free product that have migrated from the underground storage tank excavation zone and entered into subsurface structures (such as sewers or basements);

(4) Remedy hazards posed by contaminated soils

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that are excavated or exposed as a result of release confirmation, site investigation, abatement or corrective action activities. If these remedies include treatment or disposal of soils, the owner/operator must comply with applicable state and local requirements;

(5) Measure for the presence of a release where contamination is most likely to be present at the underground storage tank site. In selecting sample types, sample locations and measurement methods, the owner/operator must consider the nature of the storage substance, the type of backfill, depth to groundwater and other factors as appropriate for identifying the presence and source of the release; and

(6) Investigate to determine the possible presence of free product and begin free product removal as soon as practicable in accordance with the regulations.

Within 20 days after a release confirmation, owners and operators must submit a report to the Illinois Environmental Protection Agency which summarizes the initial abatement steps taken and any resulting information or data.

In addition to the information provided in the 20-day report, a tank owner/operator may be required to submit a corrective action plan for responding to contaminated soils and groundwater. The EPA will approve the plan only after ensuring that implementation of the plan will adequately protect human health, safety and the environment. For each confirmed release that requires a corrective action plan, the EPA will provide notice to the public by means designed to reach those

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members of the public directly affected by the release and the planned corrective action. This notice will include, but may not be limited to, public notice in local newspapers, block advertisements, public service announcements, publication in the Illinois Register, letters to individual households or personal contacts by field staff.

The aforementioned touches upon just some of the release, response and corrective action requirements outlined under the Illinois and Federal regulations. There are numerous factors which determine the classification of a leaking underground storage tank site and the extent to which you must respond to a suspected and/or confirmed release. It is highly recommended that if your municipal underground storage tank system indicates that there may be a problem or if you discover the presence of free product on your land, that you employ the immediate guidance of professionals. The failure to employ the same may cause the municipality to incur substantial liability and may also cause it to become ineligible to receive reimbursement under the Illinois Underground Storage Tank Fund. The requirements that must be met to receive money from the Fund will be the topic of next month's article. •

News items and photographs of interest indicating new developments and progress in your municipality are always of interest to our readers. You are urged to send such information to the ILLINOIS MUNICIPAL REVIEW for publication. Be sure your information is complete. All photographs should be black and white glossy prints. —Editor

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