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Alluvial Palley Floar /m•csri,¢afian • Cow Canyon, and the side canyons to Lorencito Canyon, exhibit breaks in the stream profile in multiple locations where the streams cross resistant sandstones. These steps often initiate reaches in which the canyomnarrows and is constricted. Areas of deposition in adjacent reaches provide some storage capacity for waters which may later discharge to the surface water system during storm events. This results in some intermittent reaches in which water flows until the limited storage capacity is depleted. The length of flow depends on the amount and frequency of rainfall, the amount of evapotranspiration, and the size of the deposits. Water level data is reported in Table AV-2. The wells in Lorencito Canyon were drilled within unconsolidated deposits only, while the wells at other sites may have gone deeper. Water levels at the upper Cow Canyon site, MWCWC-2, were below the bedrock for both the average depth above bedrock as well as the maximtun level of water in the well. This was also observed for the ,. average reading reported from MWCC-1 in Chimney Canyon. The thickest saturated zones were observed in the lower three wells th Lorencito Canyon but not in the upper site, MWLC~. These were seven to fourteen feet above the bedrock, or eleven to fifteen feet below the ground surface. Thicknesses of water above bedrock never reached eight feet at other sites throughout the permit area, and averaged less than seven feet. Surface Water • Flows in the dendritic streams tributary to Lorencito Canyon and the Purgatoire River within the permit area are intermittent to ephemeral. Alamosa Canyon drains the largest watershed, 15.9 squaze miles in extent. Cow Canyon drains a watershed of 3.2 square miles; Chimney Canyon, a watershed of 2.2 square miles; Little Pine Canyon 2.1 square miles; Puertecito Canyon a watershed of 1.8 square miles; and Jeff Canyon a watershed of 0.9 square miles. Lorencito Canyon drains a 69.9 squaze mile watershed which extends south to New Mexico. The Purgatoire River, the only perennial stream, drains an azea 403.7 squaze miles in extent above and including confluence with Lorencito Canyon. Baseline water monitoring was initiated th January 1996 and sampling of field parameters of flow, temperature, pH and conductivity has occurred monthly. There are four monitoring sites in Lorencito Canyon (Map 2.04.7-1.) LC-1 is located between Jeff and Little Jeff Canyons, LC-2 is located below Bonita Canyon, LC-3 is located below the confluence of Chimney and Lorencito Canyons, and LC~I is located below the confluence of Pancho Canyon. Greystone mapped flow reaches throughout the site on a monthly basis. The results are summarized in Table AV-3. • Avf.475\December 13, 1996 6