Application of Chemical and Biological Techniques to Characterize the Organic Matter Within Environmental Buffers Receiving Wastewater Effluent

Oral Presentation

Prepared by J. Ordine, K. Daniels, S. Beitel, I. Lopez, M. Park, S. Snyder
University of Arizona, 1657 E Helen St, Tucson, Arizona, 85719, United States


Contact Information: julianaordine@email.arizona.edu; 520-626-2465


ABSTRACT

As sources of freshwater continue to decline, surface waters influenced by wastewater effluents (WWEs) are becoming increasingly impacted as the volume of waste streams entering surface waters continue to rise. Approximately 15,000 wastewater treatment plants (WWTPs) in the United States produce over 32,000 million gallons of effluent per day, of which, the majority is directly discharged into surface waters. Unfortunately, many ecosystems within these surface waters receiving these effluents have experienced irreversible damage. There is a great concern over the diverse organic compounds in WWE that persists through treatment and enters surface waters. This can include bulk organic matter, trace organic contaminants (TOrCs) such as pharmaceuticals, personal care products, natural hormones, industrial/commercial compounds, and unknown organic compounds.

Of the different environmental buffers that these WWEs are discharged into during indirect potable reuse, wetlands and rivers have been shown to be the most promising to decrease these organic compounds. The aim of this study was to characterize the organic matter within secondary effluent produced in Tucson, AZ, and investigate how different types of environmental buffers can alter the composition of organic matter within the water. The Santa Cruz River and Sweetwater Wetlands, both located in Pima County, Arizona, are supplied with secondary WWE from the same WWTP; thus, providing an ideal site to compare how the organic compounds change from being released in a river compared to a wetland. Analytical methods included bulk organic parameters (i.e. EEM/TOC), targeted analysis of trace organics, and non-target analysis of unknown compounds. In addition to the chemical analysis, a variety of bioassays were applied to evaluate the bioactivity of the environmental waters. Preliminary results indicate that both the river and wetlands decrease the concentration of CECs, with additional analysis ongoing.