It was in 1885 that the first waste incinerator was built in the United States on Governors Island in New York. By the mid-20th century hundreds more were in operation across the country. But when the impacts of the water discharge and air emissions from these plants were discovered in the 1960s, policymakers had to react. The Clean Air Act (CAA) came into effect in 1970 and existing incineration facilities faced new standards that rightly banned the uncontrolled burning of municipal solid waste (MSW) and placed restrictions on particulate emissions. Facilities that refused to install the necessary technology to meet the CAA’s requirements were closed.