TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred System: The system comprises first conduit placed into the filled portion of the bag at bottom and having an outer end located outside the bag, and second conduit connected to discharge liquid into an upper portion of the bag. The second conduit is placed into the filled portion of the bag at top location. The second conduit comprises porous length such that liquid is discharged through the porous length into the bag. The second conduit is located outside the bag and is connected to at least one outlet located inside the bag. The first and second conduits comprise several substantially straight pipe sections that are connected together as the bag filling mechanism moves in the operating travel direction such that an outer end of at least one conduit remains in front of the bag. The first and second conduits are mounted in a roll on the bag filling mechanism and are unrolled as the bag filling mechanism moves in the operating travel direction such that an outer end of at least one conduit remains outside the bag. The first and second conduits are integrated into an interior side of a wall of the bag such that as the bag moves from the collapsed position to a filled position, at least one conduit is placed inside the bag. The system further comprises tank, where the first and second conduits are connected to the tank such that liquid can be circulated from the tank through the first and second conduits and back to the tank. The system further comprises heater operative to heat the liquid contained in the tank. Preferred Method: The method further involves providing ports through the bag at intervals along bottom portion of the bag and connecting the ports to first conduit, and drawing liquid from the bag through the ports and into the first conduit. The method involves providing a tank containing liquid mixed with anaerobically active bacteria, and circulating liquid from the tank into the upper portion of the bag and drawing liquid from the bottom of the bag back into the tank. The method further involves filling a second bag with organic material and circulating liquid from the tank to the second bag. The method involves heating liquid in the tank. The method involves drawing liquid from bottom of the bag and circulating the liquid into the upper portion of the bag, and drawing gas generated in the bag through the gas recovery conduit to the gas collection site until the generation of gas drops to a selected level, arresting flow of liquid into the upper portion of the bag and drawing liquid remaining in the bottom of the bag into the tank, pumping air into the bag to create an aerobic atmosphere inside the bag such that aerobic bacteria are active to compost the organic material, drawing air out of the bag and then injecting carbon dioxide into the bag to enhance anaerobic conditions in the bag, circulating liquid from the tank into the upper portion of the bag, and drawing liquid from the bottom of the bag into the tank, drawing gas generated in the bag through the gas recovery conduit to the gas collection site until the generation of gas again drops to a selected level, and repeating anaerobic digesting and aerobic composting cycles until the organic material has achieved a desired level of decomposition. The air is pumped into the bag through the first conduit, and the air is drawn out of the bag through the gas recovery conduit and carbon dioxide is injected into the bag through the gas recovery conduit. The method involves slicing the bag open to provide access for an excavating machine, and operating the excavating machine to remove decomposed organic material from the bag, preferably by positioning the bag on an inclined surface such that liquid will flow along a bottom inside surface of the bag to a low point of the bag, and a port is provided at the low point of the bag such that the liquid can be removed from the bag through the port.