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unit to qualify as wetland. This aspect was not investigated in detail, but the presence of at least some of the same species that are dominant in the well developed wetlands may indicate that some of the upland areas actually would qualify as wetland. However, for purposes of this study, none of the upland area is counted in the amount of wetland created because it is clearly very marginal as wetland and even if it would qualify now a slight decline in the elevation of the stream channel would very likely eliminate it from that category. In other words, even if it would qualify as wetland today its continued existence in that category for more than a few years is highly questionable. There is a total of 6.97 acres (essentially 7 acres) of land in both enclosures that clearly are wetland. The vast majority of the rest of the land is in the upland category and is where the required large cottonwood trees were planted. It is possible that, during wet periods and wet years, an additional acre of wetland could be found in the fringe zone between the upland and wetland units. It is important to note that the boundary between wetland and upland is not a well defined line but a zone of considerable width, especially in the southern enclosure. The slope leading from the upland areas where the large cottonwoods were planted down to the obvious wetland is generally quite gentle and shows a strong gradient from upland to wetland. There is at least ahalf-acre of land within this broad transitional zone. In the northern enclosure, this slope is somewhat steeper and therefore the transitional zone is rather narrow. But even there, small variations in the slope topography and small fingers of slightly lower elevation land encroach into the upland zone. In conclusion, the total amount of wetland present depends greatly on exactly where the line is drawn, but a value of 7 to 8 acres of wetland is reasonable. However, it would be difficult to exceed 8 acres without using a very broad definition of wetland. The photographs included in this report that specifically show the wetland enclosures illustrate many of these features. The photographs tend to show the full gamut of variation within each enclosure, although some portions of the enclosures are necessarily not shown or are obscured by other features. The boundaries shown on the maps, however, were determined by on the ground mapping using ahand-held GPS unit. Although hand-held GPS units are not extremely accurate, calibration and testing showed that for this study it was consistently within about an 8 to 12 foot error circle, at most. The unit utilized (Magellan Meridian) locks on to the new WARS system which considerably increases accuracy. Normal accuracy (without WARS) is considered to be about 8 to 10 meters (20 to 30 feet) but with WARS the accuracy increases to about 2 to 4 meters (6 to 12 feet). No waypoints were taken that did not have WAAS reception active. Coal Creek Wetlands and Wetland Mitigation DA Permit 198811488 August 2003 Page 11 of 23