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Fact Sheet 1

Caterpillar Proving Grounds Diesel Release

Fact Sheet #1

April 2011

East Peoria , Illinois


On February 18, 2011, Caterpillar Tractor Company, Inc. (CAT) was notified by the Woodford County Emergency Management Agency that residents along Ten Mile Creek had noticed a fuel odor. CAT personnel checked outfalls on the bluff below the Proving Grounds fuel station and discovered some diesel fuel seeping into a ravine which continues to Ten Mile Creek. An initial investigation around the fueling facility revealed a diesel leak in an underground line that feeds the fuel dispensers. Diesel fuel is used on the Proving Grounds property to power the earth-moving equipment being tested there. At the time the leak was found, CAT began excavating to remove the source and to find the extent of the leak. The fuel had followed a down-hill slope to a ravine on CAT property, ran down the ravine and impacted Ten-Mile Creek (about one-half mile away) with a visible sheen of diesel fuel on top of the water.

Caterpillar Proving Grounds Location of Diesel Release February 2011

How much diesel product was released to the environment?

It is not known exactly how much diesel was released, because CAT does not routinely meter the amount pumped to the equipment on the Proving Grounds.

How long could the pipe have been leaking fuel?

While it is not known the precise length of time the leak was occurring, most of the diesel observed in the soil that was excavated at the fuel station appeared to be newer fuel. As the fuel weathers, in the case of an older spill, certain chemical components separate and break down. Consequently, the chemical analyses show different proportions of certain chemical constituents than the new fuel.

What actions did Caterpillar take upon learning of the leak?

Caterpillar notified local, state, and federal officials of the leak as required by statute. Then, in consultation with Illinois EPA representatives, using CAT employees and hired contractors, they took steps to stop the movement of fuel and remove the source of the contamination.

Has the leak been stopped, and what has been done to ensure no further impacts to Ten-Mile Creek?

Yes, the leak was stopped during the week of February 20th, 2011.

CAT brought in a temporary tank truck to dispense fuel to the on-site test equipment while the fueling station was completely torn out. After a 27-foot deep excavation (100 ft. by 100 ft.) revealed the vertical extent of the contamination, confirmation soil samples were taken at the floor and at the south, east and west walls of the excavation. The sample results showed no contamination present at levels greater than state cleanup values.

To the north, on the down-hill side of the fueling station and 38 feet below it, a capture trench was constructed to collect any fuel continuing to move out of the soil from the upper part of the bluff. This effectively collects the diesel fuel and routes it to a collection pit for removal by vacuum trucks. This has prevented any further release down the slope to the ravine or to Ten-Mile Creek.

What is the chemical composition of diesel fuel and what are the potential health hazards from being exposed to these chemicals?

Diesel fuel is made up of a mixture of volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs). VOCs are easy to detect by their odors at very low levels. Some of the VOCs are considered to be harmful to humans and aquatic life at concentrations much greater than what was found in Ten Mile Creek. VOCs tend to evaporate readily, especially in open air and when tumbled along in creek water. No impacts to aquatic life were observed during surveys of Ten Mile Creek.

Should area residents be concerned about children who play in the creek being exposed to VOCs?

No. The Illinois Department of Public Health (IDPH) has reviewed analytical data from all surface water and stream bank soil samples taken along the creek during the investigation. The results show that chemicals of concern are not present at concentrations that would pose an increased health risk to residents - including children who might play in the creek.

Please note, however, that the Tazewell and Woodford County Health Departments and IDPH wish to remind homeowners along Ten Mile Creek that many septic systems along the creek discharge to the creek. Consequently, children should not be playing in the creek, because they may be exposed to harmful bacteria in the water.

Were private wells impacted by this release?

Data suggest they were not. Numerous private wells along Ten Mile Creek were tested, and laboratory results showed none of the chemicals found in diesel fuel. It was not anticipated that diesel components would be seen in the wells.

How is Caterpillar safe-guarding the fueling station to prevent further leaks?

The new fueling station that is being built in the same location as the former station will have a concrete pad and containment as before. It will also have additional safety features in accordance with plans approved by the Illinois Office of the Fire Marshal:

  • Fiberglass tanks with double-wall construction;
  • State-of-the-art remote leak detection equipment; and
  • Piping visible within the containment vault.

CAT contact: Randy Mooberry, Mgr. Plant Operations - (309) 698-5855

Illinois Environmental Protection Agency Contacts

Carol L. Fuller, Illinois EPA

Office of Community Relations

1021 North Grand Ave. E. #5

P.O. Box 19276

Springfield, IL 62794-9276

Phone: (217) 524-8807
Cara Barnett IDPH,

Toxicology Section

525 W. Jefferson Avenue

P.O. Box 19276

Springfield, IL 62761

Phone: (217) 782-5830

Additional Information

To obtain site-related documents through the Illinois EPA's Freedom of Information Act office, please send a request to the address listed below or submit a request referencing the site name Caterpillar Proving Grounds and the IEPA Site no. H2011-0155.

Illinois EPA, Freedom of Information Officer

1021 N. Grand Avenue East, P.O. Box 19276

Springfield, IL 62794-9276

Ph: (217) 782-5236, Fax: (217) 782-9290