Phosphorus characterization in sediments impacted by septic effluent at four sites in central Canada

摘要

Characterization of phosphorus(P)enriched solids was undertaken in the sediments below four mature septic system infiltration beds, where previous monitoring of phosphate(PO_4)concentra- tions in the groundwater had indicated that substantial retention of P was occurring in the vadose zone. At each site, zones of sediment P enrichment were identified by an acid extraction procedure. Acid extractable sediment P concentrations were found to be 2-5 times higher than background values, within narrow discrete zones generally 10-30 cm in thickness, located within one meter of the infiltration pipes.