Abstract: Disclosed are fermentative enrichment cultures and two pure isolates there from for use in biotransformation of halomethanes. Disclosed bioaugmentation cultures are dominated by Enterobacteriaceae, and are implemented together with one or more electron donors such as corn syrup, glucose, and the like, and a corrinoid catalyst such as vitamin B12. Disclosed cultures and implementation methods can be utilized to transform single halomethanes or mixtures of halomethanes at high rates to non-toxic end products being primarily carbon monoxide, carbon dioxide, and, organic acids.