The jury also convicted the plant's environmental control manager, Mark Kamholz, on 15 counts, most of them for violating clean air laws, according to the U.S. attorney's office.
Monserrate Shirley and brothers Mark Leonard and Bob Leonard Jr. were arrested Friday morning and charged with two countsof felony murder in the deaths of John and Jennifer Longworth, the neighbors of Shirley and Mark Leonard who were killed by the explosion at Shirley's home in the Richmond Hill area on November 10.