New Research on Storm Water Pollutant Removal Effectiveness of Compost Filtration BMPs

Construction, post-construction, and agricultural storm water regulators and designers need performance criteria of best management practices (BMPs) to effectively evaluate new practices and technologies. Conventional sediment control barriers typically only target sediment in storm water runoff, whereas new management practices should be developed to target a range of particulate and soluble pollutants commonly found in storm water. Most testing on post-construction storm water management technologies has not been conducted at public laboratories and made available in scientific journals. Recent experiments conducted by the US Department of Agriculture-Agricultural Research Service (USDA-ARS) evaluated the performance of compost filter socks in reducing storm water runoff flow transport of sediment and soluble pollutants. These experiments focused on evaluating the performance of compost filter socks on soil and paved surfaces. Simulated rainfall was applied to soil chambers packed with Hatboro silt loam or concrete veneer surfaces on a 10% slope. All runoff was collected and analyzed for hydraulic flow through rate, runoff volume, total suspended solids (TSS) concentration and load, turbidity, and total and soluble phosphorus (P) concentration and load. Results showed compost filter sock removal efficiencies for TSS concentration and load, turbidity, and total and soluble P were between 62 and 97%, 53 and 98%, and 57 and 99%, respectively. Follow up studies have been conducted by the USDA-ARS to evaluate the performance of compost filter socks on reducing: i) runoff nitrogen (N) (ammonia-N and nitrite-nitrate-N) loads, ii) runoff bacterial pathogens (fecal coliform and E. coli) loads; iii) runoff heavy metals (nickel, cadmium, chromium, copper, lead, zinc, and iron); and iv) runoff petroleum hydrocarbon loads. Results from these studies will be presented.