Submitted to: Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/12/2008
Publication Date: 3/1/2009
Citation: Codling, E.E., Faucette, L.B., Cardoso-Gendreau, F.A., Sadeghi, A.M., Pachepsky, Y.A., Shelton, D.R. 2009. Storm Water Pollution Removal Performance of Compost Filter Socks. Journal of Soil and Water Conservation. 38:1233-1239.
Interpretive Summary: Laboratory studies were carried out to test the feasibility of commercially made Filter Soxx (FS) to treat stormwater in reducing pollutant loading to surface water resources. Based on the conditions described for these experiments, FS showed to be an effective tool for stormwater managers interested in improving receiving water quality. Results demonstrated that FS were able to remove 65% and 66% of clay and silt sediment particulates present in simulated runoff. This fraction of the sediment load is typically responsible for the majority of suspended solids and turbidity found in stormwater which negatively impacts receiving water quality. Removal efficiency by FS for several heavy metals such as Cd, Cr, Cu, Ni, Pb, and Zn from runoff ranged from 37% to 72%. Furthermore, removal efficiencies increased with the addition of MetalLoxx to the FS system, ranging from 47% to 74%. Both treatments exhibited the ability to remove sediment particulate-bound metals and soluble metals from runoff. Although FS have been approved as a Best Management Practice (BMP) for controlling sediment in storm runoff, consideration should be given to implementing this BMP, with and without flocculation agents, in post-construction and urban runoff treatment train applications for improving stormwater quality.
Technical Abstract: In 2005, the US Environmental Protection Agency National Menu of Best Management Practices (BMPs) listed compost filter socks as an approved BMP for controlling sediment in storm runoff on construction sites. Filtrexx International manufactures and distributes Filter Soxx (FS). Literature suggests that FS have the ability to filter soluble pollutants typically found in urban runoff. The objectives of this study were to determine if FS with or without flocculation agent can remove (I) suspended clay and silt particulates, (II) ammonium nitrogen (NH4-N) and nitrate-nitrite nitrogen (NO3-N), (III) fecal bacteria, (IV) heavy metals, and (V) petroleum hydrocarbons from storm water runoff. Five separate (I-V) thirty-minute simulated rainfall-runoff events were applied to soil chambers packed with Hartboro silt loam or a 6 mm concrete veneer on a 10% slope, and all runoff was collected and analyzed for hydraulic flow rate, volume, pollutant concentrations, pollutant loads, and removal efficiencies. In corresponding experiments, runoff was analyzed for (I) size of sediment particles, (II) NH4-N and NO3-N, (III) total coliforms (TC) and Escherichia coli, (IV) Cd, Cr, Cu, Ni, Pb and Zn, and (V) gasoline, diesel, and motor oil, respectively. Results showed that: (I) FS removed 65% and 66% of clay (< 0.002 mm) and silt (0.002 to 0.05 mm), respectively, (II) FS removed 17%, and 11% of NH4-N and NO3-N, respectively and when NitroLoxx was added to the FS, removal of NH4-N load increased to 27%, (III) total coliform and E. coli removal efficiencies of 74% and 75%, respectively. However, when BactoLoxx was added, removal efficiency increased to 87% and 99% for TC and 89% and 99% for E. coli, respectively, (IV) FS removal efficiency for Cd, Cr, Cu, Ni, Pb, and Zn ranged from 37% to 72%, and, when MetalLoxx was added, removal efficiency ranged from 47% to 74%, and (V) FS removal efficiency for the three petroleum hydrocarbons ranged from 43% to 99% and the addition of PetroLoxx increased motor oil and gasoline removal efficiency in the FS system. This study indicates that FS (with or without flocculation agents) can remove suspended particulates, N species, bacteria, heavy metals, and petroleum hydrocarbons from storm runoff. Future research should explore the efficacy and long term exposure on performance of these practices.