Field-Scale Monitoring of PPCP/EDC Transport At Active Golf Course Sites.

In arid and semi-arid regions, the use of treated wastewater for landscape irrigation is becoming common practice and a significant asset to conserve potable water supplies.  However, studies have shown that pharmaceuticals and personal care products (PPCP) and endocrine disrupting compounds (EDCs), called PPCP/EDCs, remain present in the treated wastewater. Public interest and lack of field-scale data are leading to a concern that compounds found in irrigation water will remain persistent in the environment and contaminate groundwater. As part of a larger study (that included laboratory- and meso-scale experiments), passive drain gages (Decagon Devices) were installed in triplicate in fairways at four operational golf courses, one in Nevada and three in California, all with histories of using treated wastewater on their fairways. The gages measure water fluxes and allow collecting water samples that were subsequently analyzed for 13 compounds of different chemical classes (ranging from antibiotics to antidepressants). Monitoring periods lasted approximately 2 yr at each site, sufficiently long to allow the gages to equilibrate. Results indicated more than 100 instances of target compounds detected in water that percolated through the turf and upper 60 cm of soil. Sulfamethoxazole, Meprobamate, and Carbamazepine were most commonly found in drainage water, but Gemfibrozil, Diclofenac, Naproxen, and Triclosan were also found in more than one sample. Solute breakthrough tended to be concentrated during fall and winter periods when turf was overseeded and sites received winter precipitation. When results were converted to mass flux and represented at hectare scale, results indicated that fluxes of all compounds were less than 1 g/ha throughout the study. Numerical modeling was also undertaken to predict possible PPCP/EDC fate and transport under different field conditions, allowing better assessments of potential risks of using treated wastewater as an irrigation source.