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derived from erosion and mass wasting of the Wet Mountain uplift to the south and west. <br />Depositional thicknesses range from 5 to 100 feet in places near the mine site, with 20 feet <br />recorded in the loadout area of the mine. <br />Hydrology <br />An extensive review of both the groundwater and surface water hydrology can be found in <br />Sections 2.04.7, 2.05.6 and 4.05 of the PAP. Below is a brief summary of the groundwater and <br />surface water at the Southfield Mine. <br />Due to the extensive underground mining activities in the area, groundwater baseline information <br />was difficult to obtain. Trends for groundwater were established and have been recorded since <br />the mine opened as the Dorchester No. 2 in the 1970's. Groundwater flow is difficult to predict <br />based on the tendency for the groundwater to flood old workings in the area. Many residential <br />wells have been drilled into the old abandoned workings and provide residents with water. In the <br />mine area, evaluation of groundwater resources is based primarily on exploration drilling, <br />records of groundwater use, information on regional groundwater characteristics, monitoring <br />information, inflow into underground workings at the Southfield Mine, and historic information <br />on abandoned workings. <br />There are three categories of stratigraphic units that potentially contain groundwater aquifers that <br />occur in the permitted area: 1) the Trinidad Sandstone, 2) coals (and possibly other units) of the <br />Vermejo /Raton Formations and 3) localized river alluvium. A detailed analysis of each of these <br />aquifers is found in the PAP. All groundwater flow into these three aquifers is the direct result <br />of recharge collected from the Wet Mountains to the west. The water flow is structurally <br />controlled by the Chandler Syncline which trends northwesterly to the Arkansas River where it <br />discharges. <br />There are several wells in the area, including wells for water supply and for monitoring. <br />Additional information on these wells, as well as groundwater below and near the permitted area, <br />can be found in Section 2.04.7, Section 4.05.13, and Map 12 of the PAP. <br />Surface water in the area flows from the Wet Mountains on the west to the plains on the east then <br />bends northward toward the Arkansas River valley. Most of the streams in the area are <br />ephemeral, flowing in response to snowmelt and intense rainfall events. Much of the <br />precipitation received is absorbed into the colluvial material or is lost to evaporation and <br />transpiration. Local towns divert most of the remaining surface waters from the mountain <br />drainages for municipal use. The towns of Coal Creek, Rockvale and Florence all have <br />extensive water lines that utilize most of the water from Oak, Magpie and Newlin Creeks. Water <br />quality information taken from these districts shows elevated levels of calcium- bicarbonate, <br />magnesium, and barium. Metals such as cadmium, lead, and zinc are slightly elevated due to <br />inactive and abandoned metal mines in the area. Severe channel erosion by the downcutting <br />action of the stream's headwaters into the pre- Cambrian metamorphic rocks of the Wet <br />Mountains has led to increased levels of TSS in the streams. As these high- energy streams <br />7 <br />