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B). Two constituents, fluoride and manganese, have natural concentrations that are <br />greater than the applicable ground water standard (CDPHE, Regulation 41). <br />Historically and currently, fluoride and manganese occur at concentrations of <br />approximately 4.5 mg/L and 2 mg/L, respectively. <br />Fluoride is dissolved in water as an anion (F-) and is in general less affected by <br />geochemical reactions in the soil and aquifer than is manganese. Under natural <br />alkaline soil conditions that exist at the Salazar Ranch, manganese is initially <br />adsorbed by the soil, but is eventually oxidized to form insoluble manganese oxides. <br />Because of the oxidation reaction to insoluble manganese oxide, soils at the Salazar <br />Ranch have a virtual unlimited capacity to retain manganese. In addition to formation <br />of stable manganese oxide minerals, manganese attenuation also occurs by adsorption <br />to iron oxide surfaces and complexation with soil organic matter. Also, dissolved <br />manganese in ground water (as Mn2+) is oxidized by oxygen in aerated soils to form <br />insoluble manganese oxides Furthermore, evidence from operation of the water <br />treatment plant indicates that manganese concentrations will decline during residence <br />in the West Pit irrigation ponds due to aeration and oxidation. Because there are <br />multiple soil and pond geochemical processes that remove manganese from solution, <br />the primary focus in the soils evaluation is to describe how fluoride will interact with <br />soils, crops, and the ground water. Exhibit H addresses potential effects of fluoride <br />on waterfowl. <br />G.3.1 Soil Evaluation <br />Soils at the Salazar Ranch were evaluated to: (1) characterize baseline soil chemistry <br />within the center pivot irrigation areas and (2) assess the interaction of fluoride and <br />manganese with soils beneath the irrigation circles. This information was then used <br />to assess potential future fluoride and manganese loading to the soils and the potential <br />for leaching and/or phytotoxicity of fluoride and manganese in irrigation water. <br />Appendix D contains the full report on the soils characterization and testing. <br />Battle Mountain Resources, Inc. 32 <br />P:\Pmjmb\212-Ne nt(SenL,ri,)\SanLms\Permit Amendment- West Pit Mamgem AV5 Report d: PDFAT-APe tAm-d_vm_v5c.dm December 2007