Solvent compositions for removing petroleum residue from a substrate and methods of use thereof

A method of cleaning highway and road construction equipment comprising:

• placing equipment on a perforated grid;
• spraying a biodegradable solvent composition with a spray gun under pressure on a residue containing equipment thereby forming an aqueous sludge, wherein the solvent composition has a pH of about 7;
• filtering the aqueous sludge through the perforated grid and thus separating insoluble contaminates;
• subjecting the filtered aqueous sludge to a compressed gas and thereby separating the solvent composition from the residue;
• and
• preparing the solvent composition for recycling or disposal,
• wherein the solvent composition comprises about 30-60 weight % of a biodiesel.