Dow to Clean Up Dioxins and Other Toxins
In July, 2007 Dow Chemical Co. and U.S. Environmental Protection Agency Region 5 finalized an agreement for the corporation to clean up a six mile stretch of the Tittabawassee River between Imerman Park in Saginaw Township and Midland’s Tridge (downstream of its Midland facility). Highly elevated levels of dioxins have been found in the three “hot spots” of the river, which leads to Saginaw Bay and into Lake Huron. Measurements as high as 87,000, 69,000, and 84,000 parts per trillion were recorded. These levels greatly surpass the Michigan Department of Environmental Quality residential clean up criterion of 90 ppt for soil.
Dioxins are a group of 210 chlorinated chemicals that according to the EPA, “have been linked to some forms of cancer, reproductive problems and weakened immune systems.” Dioxins occur as an unintended by-product of chemical manufacturing and have no known use. Dow, which was founded in 1897, has manufactured such chemicals as styrene, butadiene, picric acid, mustard gas, Saran Wrap, Styrofoam, napalm, and various pesticides including chlorpyrifos (Dursban), Agent Orange, and 2,4,5-trichlorophenol (2,4,5-T). Historically, generated waste was disposed of in on-site waste ponds. When these would overflow, wastes were released into the Tittabawassee River. According to the EPA, “Past waste disposal practices, fugitive emissions and incineration at Dow have resulted in on- and off-site contamination. Dioxins and furans, chlorobenzenes, heavy metals and other materials were byproducts from the manufacture of chlorine-based products and other chemicals.
According to the Michigan Department of Community Health, “Residents of Midland and the surrounding communities could be exposed to dioxins and furans in the soil through incidental ingestion, direct dermal contact, and inhalation of soil and dust.”
A dam has been constructed to enable dredging of the contaminated river sediment. The Michigan Department of Environmental Quality is advising boaters and fishermen to “maintain a safe distance from construction activities.” The removed sediment will be disposed of in the Salzburg Road Landfill, a hazardous-waste landfill located on the Dow property.
Dow is scheduled to begin sampling an additional eleven miles of the river this year.
Fall 2009 Update: For the past two years, Dow has been in negotiations with EPA and Michigan Department of Environmental Quality (MDEQ) to determine the course of action for clean. For various reasons, negotiations have failed. Even still, during this time clean up and dredging efforts have continued in three “hot spots”, areas with the highest dioxins level detected.
Scientists then located a new hot spot in the Saginaw River where the dioxin level was measured at 1.6 million parts per trillion (ppt)—possibly the highest level of contamination ever on record for U.S. rivers and lakes.
An agreement has finally been proposed between Dow and the EPA and MDEQ. Dow may sign the agreement on October 15, 2009. EPA will hold a public comment period before signing the proposed agreement. Visit: Tittabawassee River Watch.
Petitioned Health Consultation: Dioxin Contamination in Soil in Midland, Michigan, prepared by Michigan Department of Community Health Under a Cooperative Agreement with Agency for Toxic Substances and Disease Registry
A Pilot Exposure Investigation: Dioxin Exposure in Adults Living in the Tittabawassee River Flood Plain Saginaw County, Michigan
EPA FACILITY ID: MID980994354 JULY 8, 2005 U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES Public Health Service Agency for Toxic Substances and Disease Registry Division of Health Assessment and Consultation Atlanta, Georgia 30333
-Melissa Cooper Sargent, Fall 2007
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