Benzotriazole Enrichment in Snowmelt Discharge Emanating from Engineered Snow Storage Facilities

Snowpacks in urban environments can retain a high load of anthropogenic contaminants that, upon melting, can deliver concentrated contaminant pulses into the aquatic environment. In climates with an extended period of snowfall accumulation, such as in Anchorage, Alaska, contaminant amplification within meltwater may affect aquatic ecosystem health. A spatiotemporal study of benzotriazoles on snow, meltwater and soils was performed in association with three urban snow disposal facilities. Benzotriazole elution from engineered snow disposal sites behaved similarly to inorganic salt and dissolved organic carbon (DOC) during the initial melt period, with maximum concentrations between 2.23-7.39 μg/L; similar enrichment was observed in creeks. Assays of disposal site soils revealed the presence of tolytriazole. Furthermore, using fluorescence spectroscopy and PARAFAC analysis, a modeled component representative of benzotriazoles was identified, a possible indicator of anthropogenic input rather than a unique indicator for benzotriazole compounds.