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reservoir contained 8 to 12 inches of organic soil which was the primary detenninant for this classification. Further soil investigation is requued for the "potential fen" tliat is located to the east of the dam. Hydrology The study area is located in a riparian valley that is hydrologically altered by the presence of a dam. Upstreatn of the dam the valley is flooded for the sake of stockpiling water. The resulting reservoir has fluctuated in depth and proportionate cross-sectional area of inundation. This artificial hydrologic regime has had a substantial impact on the plant commuiuties of the steep banks of the reservoir, which are largely unvegetated. Below the dam the floodplain hydrology is also artificial. The presence of the dam eliminates the natt�ral lugh flow events which are important for the sediment transport and fluvial morphology of the floodplain. The metered release of water from the reservoir also creates a more consistent water table. Despite this altered hydrologic regime, the downstream floodplain maintains a much more natural appearance than the areas above the reservoir. Additionally there are two primary tributaries that enter the reservoir stiidy area, one near the west end of the reservoir, which flows into the reservoir fi•om the southwest and the other is below the dain flowing uito the Rio Grande from the south. Several other smaller intermittent streams enter the study area, most of which are located on the south side of the reservoir. Streatn flow, shallow groundwater and reservoir (lacustrine) water are the primary source of hydrology for the delineated wetlands. Direct precipitation and surface runoff are secondary sources of hydrology. According to data produced at the National Resource Conservation Service (NRCS) Snotel Site, the average annual water equivalent in this area is approximately 45 inches a year of snow, which does not include rain in the si.uruner and fall, which would likely bring the total annual precipitation to approxirnately 60 inches a year. Other indicators of hydrology within the project boundaries include, drainage patterns, drift lines and matted vegetation. Limitations Field indicators can change with variations in hydrology and other factors. This report conservatively estimates the potential for wetlands at the site at the time of our review and does not address conditions at a given time in the future. Sugnet malces no other warranties, either expressed or implied, and our report is not a recommendation to buy, sell or develop the property. This report does not constitute a Jurisdictional Determination of Waters of the United States since such determinations must be verified by the USACE or the NRCS (as applicable), and are subject to review by the U.S. Environmental Protection Agency (USEPA). � 555 Rivergate Lane, Bi-101 Durango, Colorado 81301 Ph.970.259.9595 Fax.970.259.U050 www.sugnet.com