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MINIMUM STANDARDS FOR ACCEPTANCE OF PRELIMINARY WETLANDS DELINEATIONS A statement that the delineation has been conducted in accordance with the 1987 "Corps of Engineers Wetlands Delineation Manual." Response: This wetland delineation was conducted using the methods found in the U. S. Army Corps of Engineers 1987 Wetland Delineation Manual and published amendments. A narrative describing the wetlands. Response: Two types of wetlands occur on this property. The largest and most pronounced wetland type is associated with two old river oxbows which traverse the property and which contain obvious wetlands sustained by groundwater and collected surface water. Neaz the eastern portion of the property, this wetland area is dominated by Cattails, Beaked Sedge and Common Hornwort. Neaz the southwestern portion of the property is a lazger abandoned river oxbow which has been cut off from the main channel of the river by the railroad bed. According to maps provided to the Colorado State Engineers Office in conncetion with the Yampa and M irrigation ditch, in 1889, this old oxbow is called the Jones Slough. This slough is currently managed as a part of these irrigation ditches in as much as it contains a headgate which regulates the flow of water into the old oxbow and a headgate near the west end which diverts waters into the irrigation ditch. This old oxbow is predominately standing water, but contains a fringe wetland on either side that is dominated by Reed Canarygrass, Willows, Sedges and Spreading Bentgrass. A second apparent wetland type exists in portions of this area, which is dominated by weedy, wetland species, primarily Foxtail Bazley (FACW) which has become established by years of mine water discharge waters being dischazged onto this site. This mine discharge water was discontinued being placed on this area in the fall of 2004. After a very careful investigation of this site and in installation of 17 wetland sample plots, with excavated pits approximately 18 inches deep and in installation of six formal water monitoring wells, we conclude that these sites more correctly meet the definition of irrigated wetlands and since they do not satisfy the hydrology criteria in a natural setting without irrigation, according to the Corps of Engineers regulations, 1987 Wetland Delineation Manual and associated written guidance previously received from the Corps of Engineers regarding imgated wetlands, these areas do not contain jurisdictional wetlands subject to the provisions of Section 404 of the Clean Water Act. Justification for the wetlands boundaries. Response: The detemunadon of the wetland boundaries was delineated based upon a field surveys conducted on 2 March 2006, 5 Apri12006, 13 Apri12006 and reinspected again for the last time on 18 Apri1200b. The basis of the wetland boundaries was delineated based up a fairly abmpt vegetation boundary between the wetlands and upland areas in most areas of the proposed mine expansion area. For the lower areas, which had been subjected to several years of prolonged irrigation and which were dominated mostly by Foxtail Bazley (FACW) the primary basis of identifying the wetland boundaries in these areas was hydrology. In summary, the primary basis for delineating the wetland boundaries was vegetation and secondarily, hydrology. Of the seventeen wetland sample plots evaluated ten were found to be dominated by upland vegetation and hence could not be considered to be jurisdictional wetlands. Five of the seventeen plots (BGP-5, BGP-7, BGP-9, BGP-13 and BGP-17} were found to be dominated by wetland vegetation but were considered out on the basis of lack of positive evidence these sites