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eventually become rich until the next high cutbank is reached at which point the sequence begins again. But this is only true where the high cutbank has been recently eroded and is unprotected by vegetation. If there is vegetation on the bank or at the base of the bank then the downstream sedimentation with declining vegetation cover pattern often does not occur or is much less significant. One feature in the sand deposit that will become of considerable importance when the wetland vegetation is examined is the presence of a thick clay seam several feet under the original sandy surface. In general, mining only continued down to this clay seam and rarely did it remove the clay seam. At this point in time, all the stream channel mining has concluded under the current permits. Finally, it is important to point out that all of this land is owned by the State of Colorado. Grazing leases, oil leases, mining leases, and recreational leases have all been issued for various portions of this large parcel of land referred to collectively as the Lowry Bombing Range or Lowry Range Property. It is called that because that is what it was - a training bombing range. Much of this land contains large amounts of munitions in the form of bullets, various kinds of small bombs, and even 500 pound bombs. Some of this ordnance was never detonated and has become incredibly unstable over the years. The U.S. Army Corps of Engineers is slowly cleaning up this land, but it is a long and tedious job, as well as being quite dangerous work. Grazing leases on this land, which have been in existence for a very long time, have created some severe impacts on the surrounding hillsides. Although severe erosion is not common, the vegetation has become very thin and the soil strongly affected. Sheet erosion is not uncommon and in some drainages, astair-step pattern of headward erosion is occurring .Sometimes deep gullies can also be found. General Overview of the Stream Channel Wetlands The area studied included the entire stream channel corridor from the Quincy Bridge over Coal Creek south to the Arapahoe-Elbert County line. This is a distance of about six miles along the channel or five miles in a straight line. Except for one short section, mining over the past couple of decades influenced the most northerly about four miles of the stream channel. Portions of the most southerly two miles appear to have been mined to some extent in the far distant past, but the evidence also indicates such mining was minor in extent. It is also possible that some large depressions in the streambed south of the mining area may actually be bomb craters produced by practice bombing runs where the bombardier had rather poor aim. He missed the target by at least a mile. But, for the most part, the southern two miles of the stream channel is in a moderately natural condition and can provide a basis for comparison with recovering vegetation. Coal Creek Wetlands and Wetland Mitigation DA Permit 198811488 August 2003 Page 5 of 23