Officials say the cleanup will begin next week at one of the contaminated sites in Islip Town.
In March, Thomas Datre Jr. pleaded guilty to dumping construction debris filled with toxic chemicals at four sites. The sites include an open lot on Islip Avenue in Central Islip.
As part of a plea deal, Datre must begin the cleanup next week, according to Newsday.
Sentencing has been delayed until he cleans up the property and works on Roberto Clemente Park as well.