The role of composting in sequestering carbon Comments on the EPA's interim report on the impacts of various waste management options on carbon sequestration rates. Introduction Composting is a bioconvertion technique that will decrease the amount of biomass diverted to landfills and incinerators. Composting is a practical method to safely divert this biomass for use as a valuable bioproduct to serve as soil amendments, organic-based slow release fertilizers and plant growth stimulators. The largest fraction of this feedstock is comprised of yard trimmings, with food and paper providing a significant additional resource. The resulting material landfilled is low in vector attraction, meaning less likely to attract birds, rodents and other vermin.
Compost produces less leachate than a landfill and is much safer, cleaner and easier to treat.
The treated landfill mass, once devoid of most of its organic matter, is more likely to support the weight of the clay cap, reducing settling and the subsequent problem of surface water infiltration. This equates to approximately 44 million tons of compost. Assuming no landfill gas recovery in landfills, composting represents an atmospheric warming reduction value equal to 30 times its weight, or a total of 270 million tons of carbon dioxide equivalent. The EPA's interim report suggests that the typical application rate of compost is 3.2 wet tons per acre. To reach 100 lbs. of N per acre, approximately 25 wet tons of compost would need to be applied annually.