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. Early Saturday, an earthen dike was constructed and, in combination with portable pumping equipment, plant runoff from the affected area was retained on-site.

The wastewater treatment plant was without power for about 20 hours following the explosion, but full treatment resumed on Saturday evening. Sample results to date have shown low concentrations of site related contaminants in the plant discharge, but no levels exceeding state criteria for aquatic life or human health protection have been found in downstream waters.

Additionally, IEPA 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. One more round of inspection and sampling is planned for the stream and river the week of May 10, and Illinois EPA will update the public about the findings. We will determine whether further sampling is needed based on the results.

Illinois EPA sent a letter to the plant owners on May 4, 2004, requesting a meeting in the next two weeks to discuss investigation and cleanup, protection of the drinking water supplies, results from air and water monitoring and future use and permitting issues.

Although air monitoring at the time of the fire found some elevated levels of vinyl chloride and hydrochloric acid directly in the plume at the facility fence line, nothing was found in the community near homes. Illinois EPA is in the process of collecting soil, sediment, and surface water samples to evaluate for the potential for residential contamination from the explosion and fire. Results of these efforts will help determine if any additional samples may be needed off-site from the Formsa property.

Debris from the explosion (mainly in the form of building materials and metal piping jacketing) traveled in all directions, and has been found to date as far as three miles away. Illinois EPA is working with Formosa to retrieve and consolidate this debris on-site now. If citizens find debris related to the incident, please contact Formosa at (217) 486-6500. (Please do not move the debris, since its location may assist the investigators.)

CTEH is performing ongoing air sampling for asbestos and vinyl chloride. In addition, Formosa has set up site security and safety plans to protect site investigators and to preserve the scene of the incident that is under investigation. Parts of the site have been evaluated for asbestos-containing materials and plans are being made for proper removal and disposal of that material. Formosa is in the process of securing contractors trained and licensed to handle hazardous materials to do work on the site.