Composting Roadkill: Research and Implementation by the Virginia Department of Transportation

Abstract

More than 1.2 million deer–vehicle collisions occurred in the United States in 2014. Transportation departments are the primary agencies responsible for the removal and disposal of millions of wildlife killed on roads each year. In 2009, researchers at the Virginia Transportation Research Council began investigating composting as a means of roadkill management. This research was a response to the shortcomings of landfill and burial (the most common means of disposal in the United States) cited by transportation maintenance staff. Disposal challenges with these methods included long travel distances to landfills, landfill restrictions and costs, and the lack of viable burial areas. This paper summarizes a series of composting studies and describes the implementation efforts that led to a successful composting program for the Virginia Department of Transportation (Virginia DOT). Three roadkill composting methods were found to be effective: static compost windrows, a forced aeration system, and a rotary drum. The study findings of high temperatures, pathogen destruction, and nominal contaminant concentrations in leachate established that these composting methods are not sources of water contamination or pathogen spread. Successful pilot studies at Virginia DOT maintenance facilities led to a growing interest in adopting this method of roadkill management. Implementation efforts included coordination and training within the Virginia DOT and a regulatory agreement with the state environmental agency that allows the Virginia DOT to conduct composting without the more stringent requirements that apply to other types of material. The research findings, implementation efforts, and lessons learned described in this paper will be useful for transportation departments interested in composting as a means of roadkill management.