Establishment and performance of Vermi-activated, vegetated biofilters treating liquid dairy manure using different soil media

Liquid dairy manure was treated by biofiltration systems consisting of engineered soils, grass (Festuca elatior) and earthworms (Eisenia foetida). The trial examined 3 different soils and observed performance during vegetation establishment and initial 61 days of liquid manure irrigation. The engineered soils consist of combinations of sand, gravel and compost (SGC); municipal incinerator ash and compost (AC); and Pall saddles (1&inches; ceramic pieces) and compost (PSC). AC is known as Residual Biotech SoilRTM (RBSRTM ). AC was hypothesized to be the best filter due to structural and chemical properties.;Monitoring filtrate produced from the soil columns suggests that these systems can capture nutrients from liquid manure without introducing heavy metals into the environment at unacceptable levels. The results also suggest that high pH in the AC mixture and excessive manure application on the immature biofilters overwhelmed some of the systems to the point of failure. Nutrient and heavy metal concentrations were referenced to NYS Water Quality Standards and 6 NYCRR Part 360 Maximum Contaminant Limits for land application. Observations were made as to the operation of the system as a Best Management Practice (BMP) of an integrated animal waste management system. All columns initially produced filtrate of acceptable quality and demonstrated reductions of nutrients from the irrigated manure. As the trial progressed, the filtrate demonstrated improved system performance with declining concentrations of all metals and nutrients, except nitrogen and copper.