A local transit authority has been using SolSafe 245 for over 24 months without the the need to dispose of the solvent! They just add SolSafe 245 as needed to top off the tank!

SOLSAFE 245 Is designed for precision cleaning. SolSafe 245 is a direct replacement for 1, 1, 1 Trichlorethane, MEK, Naptha and mineral spirits. It is highly effective cleaner with a (106 kb) high solvency rating. It leaves no residue and has a light, clean odor. With its 145 degree flashpoint, SolSafe 245 is not considered hazardous for shipping by ground or air. 

Using SOLSAFE 245 (106Kb) Cleans 3 Times better than Mineral Spirits (37Kb) or Naptha (34Kb).
Its components do not appear on any of the EPA's lists of toxic or hazardous substances.

SOLSAFE 245 effectively removes:

flux, oil /grease 
adhesives, tar 
polishing compounds 
carbon, cosmoline 

SOLSAFE 245 is Safe for precision parts, it is the ideal cleaner prior to:

assembly, packaging, painting 
coating, bonding, plating 
machining, polishing. 

SOLSAFE 245 is a compatible replacement in:

hand wipe applications 
immersion cleaning 
recirculation tanks 
spray tanks 
parts washers 
ultrasonic tanks. 

SOLSAFE 245 is a formulation of alcohols and purified aliphatic hydrocarbons. Its
components do not appear on any of the EPA's lists of toxic or hazardous substances.