Fate and Transport of Emerging Contaminants and Trace Organics in Wastewater and Biosolids: A First Look

Wastewater and digested solids samples were collected from three process locations (influent, effluent and digested solids) during three separate sampling events from the San Jose/Santa Clara Water Pollution Control Plant (Plant). The Plant is a large, 632 million-liter per day (167 mgd) capacity advanced treatment plant located in South San Francisco Bay in California. Aqueous and solids samples were analyzed for a suite of microconstituents to trace levels. Levels of Pharmaceuticals and Personal Care Products (PPCPs), Steroids and Hormones (STHM), Polybrominated Diphenyl Ethers (PBDEs), Multi-residual Pesticides (MRES) and Polychlorinated Biphenyls (PCBs) were measured in all samples to parts-per-trillion or parts-per-quadrillion concentrations. PCBs and PBDEs were analyzed as individual congener concentrations and are presented as a sum of congeners. The primary objective of the study was a basic characterization of microconstituents entering and leaving the Plant to provide information to wastewater managers and the public. Of the 166 analytical endpoints measured in this study, 113 (67%) were either not detected or not quantifiable. Of the 53 analytical endpoints that were quantifiable, most (43) were removed or reduced at 75%–99% efficiency through treatment. Based on average plant flows and concentrations at the three process points, a preliminary estimate of mass balance for the compounds quantified was calculated and results are presented based on hypothesized removal processes.