Target Completion Date: January 31, 2027 Environment, Planning, and Economics
Transportation infrastructure relies heavily on many plastic or plastic containing products for applications ranging from common erosion control products to more novel practices including recycled plastic modified (RPM) asphalt mixtures. While the use of these materials provides a benefit to VDOT, concern has been growing regarding these materials propensity to shed microplastics (MPs) into the environment. Previous research has indicated that stormwater runoff is one of the primary modes of transporting this emerging pollutant throughout the environment, however additional research is needed to understand the potential sources of MPs from a DOT perspective. Further, the analytical methods that have been developed for MPs analysis vary widely with many not being applicable to MPs derived from materials like RPM asphalts. A previous study conducted at VTRC addressed this issue by developing sample preparation and analysis methods tailored for material artificially abraded RPM asphalt samples. This research seeks to build off of that previous work by (1) developing method detection limits, (2) adapting these methods to other sample types (i.e., stormwater runoff and soils) and (3) conducting field sampling of stormwater runoff, road deposited sediment, and roadside soils at sites in Virginia. This research expands on the scope of the previous effort by not only focusing on MPs that might be generated from RPM asphalt, but also other materials commonly used by VDOT, specifically rolled erosion control matting. The methodologies developed during this research and the collected field data could prove valuable to VDOT leadership should regulations regarding this emerging contaminant change. Additionally, field data from RPM asphalt pavement sites will provide the department with further insights into the propensity for this material to shed MPs back into the environment over time. This information is vital to VDOT's adoption of this material into standard practice.
Last updated: April 11, 2024