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DESCRIPTION OF CHANGES IN THIS AMENDMENT <br />Amendment 3 adds a new phase to the Pueblo East Pit. As shown on the map, Phase 2, the new phase, is <br />located immediately west of Phase 1. The addition will approximately double the size of the existing operation. <br />All of the land is under the ownership of Valco and is covered under a previous special use permit (SUP 596). <br />The effect of the amendment, besides adding Phase 2, completely redesigns the Phase 1 reclamation plan. <br />Previously, Phase lwas intended to become a water storage area after the installation of a slurry wall after the <br />conclusion of the mining in this phase. That plan has now been replaced with a plan to backfill Phase 1 with wash <br />fines from the processing of gravel and overburden removed from both Phase 1 and Phase 2. In essence, Phase 1 <br />will become a series of sediment basins with each basin revegetated as it is completed. Revegetation will involve <br />placing soil removed from the land mined over the top of the backfill and creating a blend of riparian forest and <br />wetlands. Sediment basins are often ideal for the creation of such habitats. Each of the sediment basins will be <br />separated by a containment berm, but all the sediment basins will have, as a minimum, one side that connects with <br />undisturbed land so water inside and outside the basin can move back and forth. Some basins will allow a full <br />hydrologic connection from land west to land east of the basin location. This will largely prevent the formation of <br />hydrologic shadows in the groundwater that can adversely impact wells down gradient from the fill location as <br />well as raise groundwater levels upgradient. Keeping at least one side open allows water transfer between the <br />basin and adjacent land which helps prevent the accumulation of water in a completely sealed basin that could <br />result in the creation of saline basins. <br />As these basins will be almost ideal habitats for Tamarix invasion, final revegetation will be delayed for <br />two years (or more if necessary) during which Tamarix control is implemented on the new growth medium. Once <br />the Tamarix (and any other noxious weeds) are reduced to an acceptable amount or eliminated, final revegetation <br />will occur. In the event biological control of Tamarix becomes more available and verified as to its effectiveness, <br />that may also be introduced into the final vegetation to help keep the Tamarix under control. We are aware that <br />considerable success with biological control has been found in the last couple of years and are hopeful this will <br />become more available in the near future. <br />Phase 2 will be surrounded by a sluny wall prior to mining within the sealed area. Careful examination <br />and modeling of the surrounding hydrology has shown that the plan, as designed, should have no or only minimal <br />impact on nearby wells. The plan has also included a means to allow water to flow through the gravels underneath <br />25`~ Lane to supply water to wells and also allow flushing of septic systems while avoiding the creation of <br />groundwater sumps where contaminated water could accumulate. The exit water from 25`" Lane will be able to <br />flow down a corridor between the phases and back to the river as it has done in the past. <br />As a result of the floods and severe damages to the operation that occurred in 2006, all of which have <br />been repaired with Corps of Engineers oversight, the river bank adjacent to Phase 2 will be strengthened using a <br />technique recommended by the Corps and which, after the 2006 flood events, sustained no damage. The technique <br />places short, closely spaced jetties out from the river bank and keyed into the bank. Silt and sediment accumulates <br />between the jetties which is quickly invaded by willows and sometimes cottonwoods. Two locations along the <br />river where this was done after the April and August 1999 floods experienced no damage in the 2006 floods even <br />though these placements were at locations that received greater flow force than the forces received at locations <br />where riverbank damage and failure did occur. The protective measures are considered necessary to protect the <br />slurry wall surrounding the pit. <br />When completed, Phase 2 would become a storage reservoir, but Phase 1 will likely continue to be used <br />as a sediment basin location serving the large processing plant present south of the concrete batch plant. This use <br />would continue until the sediment basins are completely filled at which point another arrangement will be <br />established for the processing plant or the plant would be relocated. <br />