NOVELTY - Dehalogenating organohalides involves either generating hydrogen molecules at first location, and providing the molecule to anaerobic dehalogenating bacteria at second location; or providing organic-containing wastewater to anode-respiring bacteria coupled to anode, generating electrons in anode, transporting electrons to cathode, providing electrons to hydrogen ions at cathode, generating hydrogen molecules, providing the molecules to anaerobic dehalogenating bacteria at contamination site which is contaminated with organohalides, and dehalogenating the organohalides.    USE - For dehalogenating organohalides (claimed) contained in soils and groundwater.    ADVANTAGE - The method helps to eliminate chemicals that are thought to be carcinogenic in human and hazardous to the natural environment. The hydrogen molecules are provided to the anaerobic dehalogenating bacteria, which then reductively dehalogenate the organohalides present at the contamination site into harmless compounds. The microbial electrolysis cell (MEC) provides hydrogen to drive the reductive dehalogenation of organohalides present in groundwater and soils without causing a secondary contamination in the groundwater or subsurface.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a system for dehalogenating organohalides comprising either: contamination site, and hydrogen source configured to supply hydrogen to the contamination site; or electrolysis cell which is configured to generate hydrogen, contamination site which is contaminated with chlorinated solvents, anaerobic dehalogenating bacteria, and distribution mechanism configured to distribute the hydrogen to the anaerobic dehalogenating bacteria; or a contamination site which is contaminated with organohalides, where the contamination site contains first subsurface zone which is saturated with groundwater, and second subsurface zone which is not saturated with groundwater, anaerobic dehalogenating bacteria, power supply, cathode which is coupled to the power supply, where the cathode is configured for placement in the first subsurface zone, and anode chamber configured to receive organic-containing wastewater, where the anode chamber contains anode which is coupled to the power supply, and anode-respiring bacteria coupled to the anode; or pump configured to pump water which is contaminated with organohalides, power supply, cathode chamber containing anaerobic dehalogenating bacteria, and cathode coupled to the power supply, where the cathode chamber is configured to receive water, the water is contaminated with organohalides, and the cathode chamber is configured to generate hydrogen gas, and anode chamber configured to receive organic-containing wastewater containing an anode coupled to the power supply and anode-respiring bacteria coupled to the anode.    DESCRIPTION OF DRAWING(S) - The figure shows a flow chart of a method for dehalogenating contaminated soils and water using a microbial electrolysis cell.