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History of Dioxin Issue in Midland

1983 - 1988 Sampling of dioxin levels in Midland soils (EPA/1983, Dow/1984, 1988) concludes soils are below federal residential clean-up guidance of 1000 ppt.
1984 Dow releases a detailed peer reviewed study on the historic sources of dioxin entitled, "Point Sources and Environmental Levels of 2378-TCDD on the Midland Plant Site of the Dow Chemical Company and in the City of Midland, Michigan." The study includeds 240 samples of soil, water, airborne particles and other samples. None of the samples outside of the Michigan Operations fence line exceeded 1000 ppt. (Nov 5)
1988 EPA report recommends additional sampling of soil, sediment and water. Federal hazardous waste permit includes requirements for sampling plans.
1996 The state became authorized to implement corrective action in Michigan for facilities that manage hazardous waste. Sampling of dioxin levels in Midland Soils (MDEQ/1996, Dow/1998) concludes soils are above the 1995 state criterion of 90 ppt.
2002 The 90 ppt generic state clean-up level for dioxin for residential property is incorporated into regulations.
2003 Hazardous Waste Management Facility Operating Licence requires Dow to address elevated dioxin levels in city of Midland as well as the Dow plant site, Tittabawassee and Saginaw Rivers, and Saginaw Bay.
2004 Dow submits to MDEQ a proposed path forward on the development of site-specific criteria for Midland, which includes soil testing and bioavailability studies.
2006 - 2011 Additional studies conducted to evaluate Midland-specific dioxin and soil characteristics. The soil sampling that was conducted as part of these studies is the basis for the initial Resolution Area.
2010 Changes made to Michigan's clean-up law (Part 201) regarding the "facility" designation allow discussions to move forward.
2012 MDEQ, Dow reach agreement on a proposed plan to resolve dioxin situation for city of Midland Soils.
2012-2014 Dow implementing plan
2016 Dow submits Corrective Action Report to DEQ