Evaluation of Anthropogenic Organic Contaminant Concentrations and Soil Chemical Properties Over Time in a Field Soil Amended with An Alkaline-Stabilized Biosolid.

Land application of biosolids on agricultural soils is a common practice in North America. An alkaline-stabilized biosolid, N-Viro Soil (NVS), has recently been produced and sold as a soil amendment in Nova Scotia, Canada.  Public concern regarding organic contaminants that may be present in sewage sludge has increased. The goal of this research is to evaluate an incubated field soil amended with increasing rates of NVS for evolved CO₂, Total C, Total N, pH, and 8 non-polar organic contaminants over a 3 month period. Four replicates each of a control and soil amended with four increasing rates of NVS were incubated in glass jars under aerobic conditions at 20°C and 18% GWC. Separate jars were included for each time period, which were sampled on eleven occasions with more frequent sampling during the first few weeks. Cumulative carbon dioxide evolution was measured titrimetrically using alkali traps. Contaminant concentrations were determined using an ultrasonic-assisted extraction technique with a solid phase extraction cleanup procedure and analyzed with an Agilent GC/MS. Preliminary CO­₂ results show a period of rapid activity followed by a gradual leveling off in the amended soil compared to a slow, nearly linear increase in the control.