30
Conclusions
After 14 months of treating a pre-treated wood pole leachate, a willow-CW provided an extra
polishing treatment step for D&F removal. Willow growth observations showed that willows
were not significantly affected in their growth and health by the pollutant contents. These results
highlight that willow-CW could be use as complementary treatment of HSSF-CW for wood pole
yard leachate. Nevertheless, the treatment chain efficiency needs to be improved to meet effluent
criteria objectives in D&F contents (0.0051 pg TEQ/L). Willow evapotranspiration could be an
interesting way to reach the zero-discharge and so avoid the effluent discharge. These
preliminary results will be complemented in spring-summer-fall 2014, with additional
physicochemical analysis (PCP, D&F, ACC), and biomass data that will be collected in the fall of
2014.
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