WHYY By The Chester Covanta incinerator, a waste-to-energy facility that burns trash from Delaware County, Philadelphia, New York City, and others, seen from Lewis Street in Chester, Pa. (Kimberly Paynter/WHYY) As the weather warms, many people open their windows to welcome spring breezes into their homes. For some residents of Chester, however, that’s not part of the plan. “Right now, we’re suffering under the effects of environmental racism in our city of Chester, Pennsylvania,” said Zulene Mayfield, who chairs the group Chester Residents Concerned for Quality Living. Delaware Valley Resource Recovery Facility, a waste-to-energy site in Chester owned by Covanta Holding Corp., incinerates about 3,500 tons of trash a day. It is one of the largest such facilities, and a 2019 study concluded it was one of the largest polluters of its kind in the country.