The Cleveland park illustrates a much broader problem. There are properties all over the country that were once landfills, dumps or uncontrolled toxic waste sites. In Chicago, for example, there was a "toxic doughnut" of landfills and industrial facilities; it’s finally getting cleaned up, but legacy pollution remains.

In East Chicago, Ind., it’s the USS Lead site, one of the most contaminated in the country.

These sites tend to be located in minority communities, according to reports commissioned by the United Church of Christ.

“Racism trumps income and class when it comes to many of these environmentally facilities that historically have gone through the path of least resistance,” said Texas Southern University professor Dr. Robert Bullard, co-author of one of those reports.