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III.C. Water Resources <br />• 1. Groundwater <br />The groundwater of the permit area is controlled by topography, strati- <br />graphy, and geological structure. Source of recharge water is found both in <br />precipitation runoff and in the water saturated Quaternary gravels which form <br />the riverbed of the North Fork Gunnison River. There is a persisent north- <br />northeastward dip of the sedimentary strata in the area. Those strata on the <br />north side of the North Fork Gunnison River, which intersect the Quaternary <br />gravels forming the riverbed, tend to be saturated. Where sufficiently trans- <br />missible, these gravels form aquifers. Recharge from precipitation runoff is <br />less important. Precipitation accumulates in permeable materials that im- <br />mediately underlie the surface, especially in isolated ponded and perched Quat- <br />ernary sediments which lie along the ephemeral drainages above and across the <br />permit area. The accumulated water is lost through upward transpiration and <br />through downward percolation. The low transmissibility of most of the sedimen- <br />tary strata in the Mesa Verde results in groundwater moving downwater through <br />fracture systems. <br />The best general information on groundwater conditions in this area is <br />contained in Price and Arnow (1974). Groundwater exists under both water table <br />(unconfined) and artesian (confined) conditions. Groundwater down to the Dakota <br />sandstone is generally unconfined. Water wells in alluvium of the Quaternary <br />period are expected to yield between 0 and 500 gallons per minute (gpm) from <br />depths varying from a few feet to more than 100 feet. Water in these aquifers <br />occurs in openings and voids between the various constituent particles. Poros- <br />ity and permeability are common]y quite high, but can be affected locally by <br />• poor sorting (clay material). Several wells have been drilled along the <br />J1 <br />