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Fact Sheet 2

Formosa Plastics Corporation Site

Fact Sheet 2

June 2004

Illiopolis, Illinois


The Formosa Plastics Corporation plant is located near Illiopolis, between Springfield and Decatur along I-72. Since the April 23, 2004 explosion and resulting fire occurred at the plant, Illinois EPA, along with other agencies, have worked to test air quality during and after the fire, water quality in creeks and streams near the site and the safety of the drinking water supply. Additional sampling has been performed by the Center for Toxicology and Environmental Health (CTEH), an environmental firm hired by Formosa. This fact sheet is a summary of all the environmental sampling data gathered to date.

Illinois EPA will continue to have a long-term presence at the site in the form of oversight regarding site investigation and proper cleanup of contamination.

What sort of air quality testing was done during the fire, right after the explosion?

Illinois EPA’s Office of Emergency Response (OER) was on the site within two hours after the explosion. They brought instruments to the site to test the air around the plant for total volatile organic compounds (VOCs), which represent the family of chemicals of concern at a plastics plant. OER checked for (1) any immediate threat to first responders or to Illinois EPA staff at the site and (2) the presence of VOCs that would indicate whether vinyl chloride (the main chemical of concern) was present in the air. Results of the screening sampling provided the necessary information to choose proper protective equipment for site workers and emergency responders as well as those in a command position outside the main fire area.

Locations that were tested for total VOCs on Saturday, April 24 included: I-72 where the plume crossed the road; the road just south of the plant; Mechanicsburg; Buffalo and Lanesville; as well as on the plant property. During the two days following the explosion and fire, OER sampled on the plant property and around the entire perimeter. During that time, no chemical contamination was found at a level that would present a hazard for public health in the community.

When the initial readings showed total VOCs close to a worker safety level, a more chemical-specific piece of equipment was used – a Draeger system – which can test for the presence of vinyl chloride. This was used in two instances, on Cope Road and along I-72 in the smoke plume. The results for vinyl chloride were ten times less than the worker safety standard.

Hydrochloric acid gas (HCl), a by-product of burning vinyl chloride, was also monitored during the fire by CTEH, and no contamination levels were found in the air in the community. Nor did Illinois EPA’s OER observe the presence of HCl during the two days after the blast (even when staff was in the smoke plume), and HCl would produce obvious discomfort (e.g., burning of eyes, burning in lungs), if this chemical were present at even fairly low levels.

I understand that Formosa hired CTEH, an environmental engineering firm, to perform air monitoring on the site and in the community. Have any of the test results revealed chemical levels that a present a hazard for public health?

No. Sampling results for vinyl chloride and asbestos fibers has continued in the community since the fire. Formosa sends a daily report to Illinois EPA with the previous day’s findings. To date, none of the sampling results have exceeded recommended federal safety standards. An asbestos standard has been established for site workers, with asbestos fibers not to exceed 0.1 fiber per cubic centimeter of air in the work zone. While there is no established level for asbestos in a community, Illinois Department of Public Health reviews measurements made in the outside air and compares those to this worker safety number. The measurements in the community have so far stayed from one to four percent of the worker safety standard, and that is considered within “background levels” of asbestos in most urban areas and safe for the general population.

Vinyl chloride and other VOCs would not normally be found in “background” samples. However, the trace amounts of these site-related contaminants continue to be measured in the low parts per million range on the site, within federal air emissions standards. In the community, the measurements show no detectable amounts for vinyl chloride.

What sampling was done on the public drinking water supply?

Illinois EPA staff collected water samples for VOCs and bacteria from five locations within the Illiopolis community water supply, the water supply at Illiopolis/Formosa Plastics, and the Mt. Auburn and Mechanicsburg-Buffalo community water supply wells. The results of these samples were all negative for site-related contamination. In addition, Illinois EPA staff made an inspection of the structural integrity of the interconnected Illiopolis/ Formosa Plastics water supplies. At this time, the Illinois EPA is confident that the system’s integrity was not compromised by the explosion or subsequent fire. Illiopolis will continue to monitor VOCs at the public water supply plant on a monthly basis for the next several months.

What can you tell us about the water quality in the ditches and streams that run south of the site?

Illinois EPA staff performed water sampling at the plant discharge location, upstream, and at six stream locations downstream from the Formosa plant. The samples were collected in an unnamed stream flowing southeast from the plant, in Long Point Slough, and in the Sangamon River. Following the explosion, a volume of fire fighting runoff water was released. However, an earthen dike was constructed on Saturday, April 24, 2004 and plant runoff from the affected area was retained on the site.

Full treatment resumed at the wastewater treatment plant on Saturday evening following the explosion and fire. The treatment plant continues to operate normally at a reduced load (since the plant is not in operation). Sample results to date have shown low concentrations of site related contaminants in the plant discharge, but no levels exceeding state criteria for human health or aquatic life protection have been found in downstream waters. Illinois EPA staff continue to monitor the treatment plant at least once per week.

Additionally, Illinois EPA staff, along with Illinois Department of Natural Resources biologists, made repeated observations of the stream macroinvertebrates (small bugs), fish, any odors or visible sheen both upstream and downstream from the site. To date, no apparent adverse effects were observed in the stream organisms. Illinois EPA will continue chemical sampling of the unnamed stream every other week and will perform a facility-related stream survey this summer, which includes chemical monitoring and a biological survey.

Dioxin may have been formed during the smoldering phases of the fire at the plant. A few initial samples were taken to test for dioxin on the site. Only one sample that was taken in sediments at the surface water outfall showed dioxin at a level (in parts per trillion) that is slightly greater than the U.S. EPA comparable background level used for screening. Based on the limited dioxin sampling done so far, Illinois EPA has determined that a more extensive sampling project (both on and off the site) is needed to define whether dioxin is present above background levels, and whether it is an issue of concern. Formosa is developing a work plan for this activity.

Will there be a comprehensive environmental investigation at the site?

Yes. Illinois EPA has requested that Formosa provide a comprehensive sampling plan for all site-related chemicals in soils, surface water and groundwater both on and off the plant site. Illinois EPA will have oversight for the environmental investigation and will split a certain number of samples with the Illinois EPA to confirm analytical results. Much of the environmental sampling on the site will follow the completion of the investigations being conducted by the U.S. Chemical Safety and Hazard Investigation Board and OSHA as to the cause of the incident.

Information Repository

Illinois EPA has established a public repository for site-related information at the Illiopolis/Niantic Public Library District at Sixth and Mary Streets in Illiopolis. As Illinois EPA receives reports related to the investigation, monitoring and cleanup, we will make these items available in the repository (in the library reference section) where residents may view and copy them at their convenience. The library hours are Monday and Friday – 1:00 to 5:00 p.m., Tuesday and Thursday – 1:00 to 8:00 p.m., Wednesday – 10:00 a.m. to 5:00 p.m., and Saturday – 10:00 a.m. to 4:00 p.m. Illinois EPA will make updates to the web page for the Village of Illiopolis. You may find this fact sheet and other updates at

For more information, you may contact:

Carol Fuller, Community Relations Coordinator

Illinois EPA, Office of Community Relations

(217) 524-8807
Joe Dombrowski, Project Manager

Illinois EPA State Sites Unit

(217) 558-2564
Michael Moomey, Section Chief

Toxicology Section, Environmental Health

Illinois Department of Public Health

525 W. Jefferson Street

Springfield, Illinois 62761

(217) 782-5830