Third Year Report of the Nitrate Addition Pilot Test in the Hypolimnion of Onondaga Lake (2013)
This report describes the third year of a three-year pilot test being conducted to maintain nitrate in the hypolimnion of Onondaga Lake in order to mitigate the release and/or production of methylmercury. Methylmercury is a substance that bioaccumulates in lake biota resulting in concentrations in some species and sizes of fish that make them unsuitable for human consumption. The nitrate addition pilot test was conducted to further enhance benefits of nitrate that resulted from the 2004 Metro upgrades.
The purpose of the nitrate addition pilot test is to demonstrate that a widely-available nitrate solution can be added and mixed with lake bottom waters to effectively limit the release of methylmercury from sediment when the lake is thermally stratified and thereby reduce accumulations of methylmercury in hypolimnion waters.Results from this pilot test also provide additional information about the horizontal distribution of nitrate.
For the 2013 portion of the pilot test, as in 2011 and 2012, liquid nitrate solution was diluted with upper lake waters and added directly to the lower waters at three locations in the profundal zone of the lake. One application location was in the northern basin of Onondaga Lake, and the other two application locations were in the southern basin of the lake. The three application locations were the same as those where nitrate was applied in 2011 and 2012 and were at or near the center of one third of the Onondaga Lake hypolimnion water volume.
Report for the Third Year of The Nitrate Addition Pilot Test in the Hypolimnion of Onondaga Lake (2013)- June 2014
Part One- Report and Appendicies A-B (PDF) (4.2 MB, 89 pages)
Part Two- Appendicies C-F (PDF) (4.7 MB, 146 pages)