The interesting thing about Michigan, is that it is not required in West Michigan because we are currently clean...
However, it is required in Chicago and almost all of our gas comes through the Chicago pipeline and we end up using the required blend for that area.
I'll have to see when that is, but I believe it's the same as SE Michigan.
SE Michigan Summer Time Gasoline in effect June 1
With the long awaited return of our Michigan summer comes the extra measures required to monitor ozone and reduce harmful smog levels in Southeast Michigan.
The Michigan Department of Agriculture (MDA) is charged with enforcing ozone protection measures in accordance with Michigan's Motor Fuel Quality Act. This environmentally friendly program, started in 1996, will be mostly transparent to consumers, who may notice a slight increase in fuel efficiency using the slower to evaporate gasoline. Gasoline stations in the eight - county Southeast Michigan area, however, must sell only the summer-formula gas and meet other state and federal requirements. Use of the reformulated gasoline will prevent the release into the atmosphere of an estimated 28 tons of smog-causing compounds per day.
The Act requires that gasoline sold or dispensed in Lenawee, Livingston, Macomb, Monroe, Oakland, St. Clair, Washtenaw, and Wayne counties from June 1 through September 15 each year can not exceed 7.0 pounds per square inch (psi) vapor pressure. (MCL 290.650d). During this period MDA inspectors will conduct on-site testing and collect fuel samples for laboratory analysis. Fines and other sanctions may be levied against those found in violation of the 7.0 psi requirement.
