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2011 Annual Status Report Aggregate industries: Greeley F Street Site January 17, 2012 Prior to the flood event, the planned final water surface elevation in the Area A wetland had not completely established. It is believed that the water surface level was affected by dewatering in the general vicinity by aggregate mining on adjacent properties. As flood water levels recede, it is likely that the water level in The East Side Pond will lower, exposing, once again, the inner wetland fringe of vegetation in Area A. Vegetation cover is expected to re- establish naturally when the water level drops, likely sorted by hydric zones as distance from the standing water increases. A total of twenty (20) plant species were recorded in this area in 2011. Approximately 65 percent of these have a wetland indicator status of Facultative or wetter. Cover by weedy species is Tess than 10 percent. None of the species included in the Colorado State "A List" of weeds occurred on the site. No trees or shrubs were planted in this area. Upland areas surrounding Area A continue to support an established grass community that includes tall wheatgrass (Thinopyrum ponticum), Canada wild rye (Elymus canadensis), meadow fescue (Festuca pratensis), and alkali sacaton (Sporobolus airoides). This area also supports common sunflower (Helianthus annuus), as well as small amounts of cheat grass (Anisantha tectorum), a Colorado "List C" noxious weed (Colorado Department of Agriculture 2010). It was noted in 2007 through 2009 annual reports that surface hydrology appeared to be expanding in a broad bench area adjacent to, and south of, Area A (Figure 3). This bench supported additional potential wetlands, dominated by stands of reed canarygrass (Phalaroides arundinacea) and broad - leaved cattails, The June 15, 2010 flood event inundated this area. The northern portion of this area is still inundated in 2011. Coyote (Salix exigua) and peach - leaved willows are emerging from the edges of the shallow water. Large, dense stands of reed canarygrass continue to expand. Patches of bare ground observed in this area in 2008 appear to provide a perfect substrate for willow and cottonwood germination and establishment. In places, young trees are establishing into almost solid stands. It is expected that over time, these bare soil areas will continue to by colonized by herbaceous species from surrounding areas such as broad - leaved cattails, reed canarygrass, horseweed, meadow fescue, and alkali sacaton. AREAS B AND C The 2010 flood breached the berm separating the East and West Side Ponds (and wetland Areas B and C). The gas pipeline contained in the berm was exposed. Since the flood, the gas pipeline has now been bored underground, beneath the channel that now connects the two ponds. Water that filled the West and East Side Ponds to bank -full during the flood appear to have receded somewhat. However, the ponds still have higher water levels than in 2009, prior to the flood. Wetland mitigation plantings in Areas B and C were designed to establish on constructed terraces /benches along the north side of the excavated pit (Figures 2 and 4). On -site de- watering ceased on or about July 11, 2008. Wetland development was dependant on inundation and saturation from the water in the pit once the final surface water elevation was attained. Prior to the flood, unexpected low water levels were thought to be the result of on -going mining and dewatering on adjacent properties immediately north of the F Street site. As these actions continue, it is presumed that the water level in the ponds will continue to be negatively impacted and water levels will lower. An existing wetland has persisted in the northeast corner of Area B since the inception of area monitoring (Figure 4). Overall, it appears this wetland has expanded since 2007 when it was 2 •