Fate of wastewater contaminants in rivers: Using conservative-tracer based transfer functions to assess reactive transport

• DOI: 10.1016/j.scitotenv.2018.11.379
• Publication Date: 2018-11-27T17:53:29Z
• Authors: Gaëlle Guillet; Julia L.A. Knapp; Sylvain Merel; Olaf A. Cirpka; Peter Grathwohl; Christian Zwiener; Marc Schwientek
• Keywords: TRACER; Outflow; Inflow

Interpreting the fate of wastewater contaminants in streams is difficult because their inputs vary time and several processes synchronously affect reactive transport. We present a method to disentangle various influences by performing conservative-tracer test while sampling stream section at locations for chemical analysis micropollutants. By comparing outflow concentrations with tracer signal convoluted inflow series, we estimated reaction rate coefficients calculated contaminant removal along river section. The was tested River Steinlach, Germany, where 38 were monitored. Comparing day-time night-time experiments allowed distinguishing photo-dependent degradation from other elimination processes. While showed be highly efficient metroprolol, bisoprolol, venlafaxine, its impact on similar scale photo-independent when averaged over 24 h. For selection compounds analyzed study, bio- photodegradation higher than previous field studies. In Steinlach observed extraordinarily effective that may due proportion treated wastewater, temperature, DOC nitrate concentrations, but also surface volume ratio low flow conditions favorizes through shallow water column larger transient storage comparable