Metals were analyzed in filtered and unfiltered samples. The
unfiltered samples were stabilized with HNO3 (10 mL/L, 65%)
directly after sampling, the filtered samples after filtration. Hg
was determined only in unfiltered samples. Stabilizer was placed
in glass bottles before sampling (10 mL/L, 0.5% K2Cr2O7 in 32.5%
HNO3 supra-pure). The other metal concentrations were measured
in