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II 0.32 26.1 35.4 <br />IV 0.31 43.4 54.2 <br />Sum of I to IV 103.8 132.5 <br />5 0.32 59.6 74.5 <br />PSSA 5 will increase the capacity of the overall storage by about 57 percent. The <br />average annual solution application rates will increase from about 14,700 gpm <br />without Phase 5 (using the values in the Water Balance table on p.10 of the <br />AMEC report) to 29,100 gpm in 2014 when the maximum flow rates are reached. <br />The increased capacity of the Phase 5 PSSA will accommodate some of this <br />increase while improved operations that provide more flexibility in moving <br />solution around the VLF will accommodate the rest. The results of the dynamic <br />water balance evaluations show that the VLF can be operated without exceeding <br />the PSSA volumes. <br />It is beyond the scope of this review to rerun the model; however a review of <br />the input parameters and the modeling indicates a consistent methodology. <br />Furthermore, the model was calibrated against real operating conditions during <br />2006. The model also includes contingency inflows for 12 hours of drain down <br />(operating contingency) and a 100-year/24-hour design storm. <br />My review of the dynamic water balance model indicates that it is more realistic <br />than the static model for the large VLF at Cresson. It is an important <br />improvement in increasing the confidence in the overall fluid management of the <br />Cresson VLF. <br />4. Overall Design of Infiltration Layer - East Cresson <br />The present foundation conditions for the East Cresson Overburden Storage <br />facility consists of clayey materials. The site remains wet for a significant part of <br />the year as a result of the northerly aspect of the site and the presence of clayey <br />foundation materials. Once the overburden storage facility is constructed it will <br />be regarded and covered and it is expected that the surface may behave similar <br />to present site conditions. Present infiltration rates into the subsoil and finally <br />into the Cripple Creek Diatreme, are controlled by site conditions, i.e. the clayey <br />nature of the foundation soils and the northerly aspect of the site. <br />The design of the overburden handling and storage facility in East Cresson relies <br />on the site characteristics to develop an environmentally protective facility. It is <br />proposed that some of the clayey foundation materials be removed and placed <br />on top of the facility as a cover to reduce infiltration from that of a bare <br />overburden storage facility. In effect the present surface soils conditions will be <br />re-established on top of the East Cresson storage facility. This is a very sound <br />7