Superfund Research Program
Remediation of Asbestos Particles
- Project Summary
To minimize health risk from serpentine asbestos waste piles or open asbestos mine sites, the Remediation of Asbestos Particles Project explored phytoremediation as a cost-effective and sustainable remediation strategy, building on remediation research with heavy metal polluted soils (Dietterich LH, Gonneau C, Casper BB. Ecol. Appl. 2017). Early experiments for this project revealed that crop cultivars can thrive in the presence of asbestos in soil, suggesting phytoremediation as a promising strategy for remediation of asbestos contaminated sites (Mohanty SK, Gonneau C, Salamatipour A, Pietrofesa RA, Casper B., J. Hazard Mater. 2018). However, there was no evidence that arbuscular mycorrhizae inoculum or grass ecotypes from naturally occurring serpentile soils was beneficial in asbestos-contaminated soils. Still, phytostabilization can be critical to minimizing asbestos exposure from mines or waste disposal sites where the recommended remediation method of capping is too costly or not feasible (Gonneau C, Mohanty SK, Dietterich LH, Hwang WT, Willenbring JK, Casper BB. Plant Soil, 2017). When asbestos waste sites have nutrient poor soil, organic soil amendments are necessary to support plant growth. Thus, whether the amendment may alter the movement of asbestos fibers in soil water needs to be considered. This project also tested four commercially available organic soil amendments. Two of the four caused leaching of chrysotile fibers, but only with fiber size below 10 micrometers-the threshold size that the EPA currently uses for measuring asbestos in water. Therefore, a potential tradeoff between plant growth and asbestos mobility must be considered in choosing soil amendments (Gonneau C, Casper BB. in revision for J. Hazard Mater).