Dry cleaners can contaminate ground water due to various chemicals and solvents used in the dry-cleaning process. Perchloroethylene (perc) is the most common cleaning solvent used in the dry-cleaning industry. Spills, leaks, or improper disposal can cause releases of these solvents, which have the potential to contaminant soil and ground water. Historically, some dry cleaners may have discarded wastes by pouring wastewater into sewers, throwing used filters and sludge into the trash, or simply dumping wastewater on the ground. These disposal practices can result in contamination of soil and infiltration to ground water.