Effects of Lime Amendment on the pH of Engineered Soil Mix for the Purposes of Bioretention

Abstract

Storm-water management strategies increasingly focus on the implementation of infiltration-based best management practices (BMPs) such as swales, bioretention basins, and rain gardens. The surface vegetation and underlying soil in these BMPs remove a variety of pollutants including heavy metals and nutrients from urban storm-water runoff. The successful attenuation of these storm-water stressors is largely influenced by the physical and chemical properties of the soils used in these systems. Controlled-condition research is being conducted using pilot-scale swales and rain gardens at U.S. EPA’s Urban Watershed Research Facility in Edison, N.J. to evaluate their performance and collect data that would help in understanding the engineering design. The first phase of this research was to evaluate and select the most appropriate soil media for use in infiltration-based BMPs for the efficient removal of heavy metals and nutrients. The objective of this laboratory incubation study was to determine how the acidic pH of an engineered infield soil media could be improved to the target pH range