Use of Artificial Wetland Technology for Treating Equipment Wash Water.

During the summer of 2011, the University of Massachusetts Turfgrass Research Center constructed a small artificial wetland called a Vegetated Sand Bed to treat the water used to wash the facilities mowing and spraying equipment for reuse. During normal operation, nitrate from equipment washing and clipping degradation entered the system at 2.9 mg/L NO₃-N which dropped to 0.4 mg/L at the outlet to the system. During the fall of 2015, the system was spiked with a 5-10-5 fertilizer. Measured influent nitrogen concentrations were 72.8 and 20.5 mg/l of ammonia-N and nitrate-N, respectively. Using the first bed with no addition of water, these concentrations had dropped to less than 5 mg/L within 96 hours of application. A second, larger spike of fertilizer was made later in the fall to allow the calculation of a microbial rate constant for both ammonia and nitrate removal, -0.15 and -0.19 days^-1, respectively. Currently data is being collected for Tebuconazole, Boscalid, Chlorpyrifos, Imidacloprid, 2,4-D  and Pendimethalin.