2014-11-21_PERMIT FILE - C1996084 (23)

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Rulc 2: Perrtits Results from the laboratory analyses was interpreted through the use of vilinear and Stiff diagrams. These diagrams indicate principal cation and anion milliequivalents per liter and are useful for determining water type. The principal water type observed in the windmills is a sodium bicarbonate type. This water is typically neuval to partially alkaline, with low hardness, and low to moderate salinity. The pH ranges from 8.32 to 9.71 and hardness ranges from 166 to 80 mg/L. Total dissolved solids in the samples ranged from 660 to 800 mg/L (filterable residue). All parameters requved for analysis were compared with the Colorado Department of Health, Water Quality Convol Division The Basic Standards for Ground Water 3.11.0 (04/30/96), which include and specify secondary drinking water standards, agricultural standards, human health standards and total dissolved solids standards. In addition, sodium absorption ratios (SAR) and conductivity measurements were compared to Mined Land Reclamation Division Guidelines, "Division Procedures for the Assessment of Material Damage with Respect to Alluvial Valley Floors, The Cumulative Hydrologic Impact Assessment, and Subsidence at Coal Mines (11/87)." The standards and maximums observed at a site which were exceeding are listed in Exhibit 7. Exceedances for total dissolved solids were observed in windmills WMLPC-1 and WMCWC-1. The pH standards were exceeded in windmills WMCWC-2, WMBC-2 and WMLPC-1. SAR levels ranged from 6.70 to 7.60. Electrical conductivity ranged from 0.650 to 1.439 mmhos/cm. • Surface Water The Lorencito Canyon Mine is located on tributaries south of the Purgatoire River, 2.7 miles east of Weston, Colorado. The headwaters of the Purgatoire are located eighteen miles west of the permit area, and the river is draining 403.7 square miles of watershed at its confluence with Lorencito Canyon. The Purgatoire is a vibutary of the Arkansas River. All baseline data collected for surface water resources is contained in Exhibit 8, Surface Water Technical Report. A map presenting the hydrologic features of the site is included and describes location of water intakes, ditches, reservoirs, wells, and current use within one mile of the proposed permit area. Locations of all monitoring points are depicted and elevations included on Map 2.04.7-1. Subsurface water is not included in this map but is discussed in the Groundwater Technical Report. This is since most groundwater onsite is discontinuous. Surface water bodies are included on this map along with spoil, waste, dams, and embankment areas. Locations of gas wells are also included. Watershed Delineation and Drainage Basin Characteristics Watersheds in the area display dendritic drainage patterns chazacteristic of flow through relatively flat-lying, generally uniform geologic features (Lett, et al., 1982). Eleven drainage basins are within the permit boundary or received drainage from within the permit boundary. All of these • PERMR.~]6\Darmhr 20, 1996 2'04-2`