Jurors also returned a guilty verdict against one of the contractor's former employees but acquitted company President Cliff Berry II on similar charges.
Cliff Berry Inc. and former company former environmental director Jeff Smith were convicted on two counts of grand theft and two counts of organized scheme to defraud, The Miami Herald said.
Investigators found that Cliff Berry tankers that were supposed to be hauling wastewater from the compound were instead carrying stolen fuel, later sold to yacht operators and at Opa-locka Airport.
The verdict brings to a close a wide-ranging case of corruption and influence peddling that led to the indictment of 27 people and corporations beginning in mid-2004.
Notable deaths of 2014 [PHOTOS]