The E-Check program is a vehicle emissions testing program designed to identify motor vehicles emitting excessive levels of pollutants into the air. The test, required in 14 counties every two years, applies to gasoline and diesel-powered vehicles up to 25 years old and weighing 10,000 pounds or less. Agricultural vehicles are exempt. Drivers in Butler County are required to test their vehicles for emissions. Brownfield properties located in economically disadvantaged areas are eligible for a greater tax credit from the state than properties outside these areas.
Properties located outside economically disadvantaged areas are eligible for a lesser tax credit.
These sites may be operating or abandoned industrial facilities, contaminated or potentially contaminated public water supplies with the source or contamination undiscovered, or other locations where the environmental media is contaminated through a variety of waste management activities. Eight of these are situated in Middletown, four in Hamilton, four in Oxford, four in Fairfield, two in West Chester, and individual sites in Ross, Trenton, Seven Mile, and Shandon. Hamilton is the county's largest public water system. The Water Association, Butler County Water and Sewer, Fairfield, Middletown, Monroe, New Miami, Oxford, Seven Mile, and Trenton use groundwater for their source of water. Only Port Union uses surface water, which the system purchases from Cincinnati.