Kay's property is located 9,000 feet above sea level which means non-aerated composting can take years to complete. Her aerated O2Compost Micro-Bin system composts manure from two horses in a much more timely manner. Her bins are set into the side of a hill to maximize ease of use (dump from the top, unload from the bottom). Some of the finished compost is used to fertilize the pasture while the rest is given away to neighbors and friends.