ENVIRONMENTAL CONDITIONS OF GREEN VALLEY LAKE
Initial results indicate pH is slightly acidic (pH=6.4) near the locations of AMD input and increases to the east (pH=8.30). Organic matter content, based on LOI, is higher in the older portion of the lake (7-33 wt %) due to the influence of vegetation. Additionally, temperature, total dissolved solids, and dissolved oxygen decreases with depth, while salinity increases slightly with depth.
Future results are expected to show that water in the northwest portion of the lake contain elevated dissolved metal concentrations due to mixing of lake water with AMD in this area. Likewise, it is anticipated that core samples from this area will have elevated trace metals concentrations. Elevated metal concentrations could result in increased metal bioaccumulation and toxicity to organisms living in the lake. Overall, the data will provide important information for establishing the aquatic ecosystem health, particularly for organisms that live in or near the sediment-water interface where contaminants may be sequestered.