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<br />aquifers are quite Impermeable. ~b springs are found In the upper part <br />of the basin, and old mine workings In the VermeJo Formation appear to <br />create limited-area aquifers. Monitoring well data fran the Permit Area <br />were used to examining the potential for water movement within the <br />Ve~neJo Formation, but information on other geologic units Is from <br />published sources,'fteld examination and personal cortmunication with <br />state and federal officials with knowledge of the region. <br />The obvious source of recharge for all geologic units in the <br />synclinal basin is direct precipitation and surface runoff from the <br />granitic Net Mountains to the south and west. Water In the ephemeral <br />stream charnels must cross the Wet Mountain fault, then successive <br />subcrops of Pierre Shale, Trinidad Sandstone and the VermeJo Fon~tion <br />before coming In direct contact with the Raton and Poison Canyon <br />Formation sandstone. Recharge to these units would occur through the <br />• unconsolidated Verdos All velum or thrwgh direct ephemeral-stream <br />contact with outcrops of the various geologic units. <br />Effects of the Wet Mountain Fault zone on ground water recharge are <br />not doamented. The thrust fault has resulted In steep up-warping of <br />sedimentary units to the synclinal basin. The fault plane, with Its <br />highly fractured granite and mixture of sediments, may serve to provide <br />a path for ground water in recharging aquifers belay the Pierre Shale. <br />This may account In part for the small volume of ground water In the <br />upper part of the basin (above the Pierre Shale). <br />Direction of grandivater movement In the VenneJo Formation and <br />Trinidad Sandstone should be primarily da+n~lp from the recharge zone <br />at the outcrop, and sernrxiarily parallel to the shoreline at the time of <br />deposition. Water movement is restricted by lithologlc changes In the <br />direction normal Co the bedding planes. Lenticularlty within each <br />fon~tlon hinders groundwater movement perpendicular to the linear <br />trend of the depositional envlrorment: Figure 2.04.7 Cld) Illustrates <br />• the anticipated direction of groundwater movement In VermeJo Fornation <br />Inside the synclinal basin. <br />14 <br />