Remediation of vehicle wash sediments contaminated with hydrocarbons: A field demonstration

Abstract

Military training reservations contain vehicle wash facilities where combat vehicles and other equipment are washed after field maneuvers. During this process, sediments containing significant concentrations of petroleum hydrocarbons accumulate in concrete sedimentation basins. Conventional treatment methods to decontaminate these sediments include landfill disposal or land application. However, vegetative remediation systems may offer a cost-effective alternative. A phytoremediation design that reduces petroleum hydrocarbons to acceptable levels and is simple to manage was developed for the Central Vehicle Wash Facility at Fort Riley, Kansas. Two treatments using vegetation and fertilizer were compared to a treatment of fertilizer and no vegetation in a 3-year study. Initial hydrocarbon concentrations, determined as total petroleum hydrocarbons, averaged about 800 mg_TPH/kg_soil. All treatments resulted in reductions in total petroleum hydrocarbon concentrations of about 75% after 1 year, suggesting that hydrocarbons in the motor vehicle wash sediments have high biodegradability. Although no significant differences in hydrocarbon degradation were observed among treatments, the benefits of establishing vegetation to cover sediments during treatment suggests phytoremediation as a useful low-cost tool to manage similar hydrocarbon impacted vehicle wash sediments. © 2011 American Institute of Chemical Engineers Environ Prog, 2012