Applications of Environmental Aquatic Chemistry, 3rd Edition

221Chapter 5: Behavior of Metal Species in the Natural Environment

erosion and shallow groundwater inows carrying dissolved zinc between site 5 and

the conuence of the receiving stream and the mine drainage.

For Cu, Figure 5.9, sites 3 and 4 below the conuence show a decrease that is

mainly due to dilution. As with Zn, Cu concentrations at site 5 are about 80% higher

than what was predicted from simple mixing, again suggesting a source of metals

between sites 4 and 5. The Cu increase is still apparent at site 6, although additional

dilution has occurred. At sites 7–10, Cu concentrations are about 50–73% lower than

predicted by simple mixing. This suggests that chemical removal processes such as

precipitation and adsorption to sediments are ...