The Cubs and Reds aren't the only contributions from our neighboring states' metropolitan areas.

EPA tells us that 45 areas across the United States have failed to attain minimum standards for ground-level ozone (smog). Indiana, however, seems to have done reasonably well with the only nonattainment areas bleeding into the state from Chicago and Cincinnati.  See map. 

In 2008, EPA set the ground-level ozone standard at 75 ppb measured over eight hours.  The previous standard was 80 ppb set in 1997.  EPA has identified fewer areas that do not meet the 2008 standards in comparison to those exceeding the 1997 standards. 

The Clean Air Act requires EPA to review and revise air quality standards every five years.  EPA had previously proposed to change the 2008 standard from 75 parts per billion measured over eight hours to 70 parts per billion. An advisory committee had recommended a range of 60 to 70 parts per billion.  The Obama Administration rejected the EPA's proposal, based upon cost of implementation and impact of stricter regulations on business. 

By doing so, the President has been sued by several environmental and public health groups argue that his decision violated the law. 

Nearly all of the 45 nonattainment areas have implemented remediation programs to improve air quality.  Three areas in two states - Wyoming and California - are identified for the first time as failing to meet smog standards. Wyoming?  Really?  Are you kidding us here?  Apparently not. 

The EPA has designated the Upper Green River Basin area of Wyoming as a nonattainment area due to a boom in natural gas drilling.  Substances contributing pollution, including volatile organic compounds and nitrogen oxides released by the drilling of new wells and equipment maintenance. Wyoming is the only state that has not previously had an area designated nonattainment for ozone.