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The word, "semi-dedicated" is used because there is still a minable asset (layer of clay material) located <br /> beneath the fill that currently occupies this area of mine property. When General Shale determines that <br /> it wishes to utilize this asset, 100-year flows will be routed in a different manner to the original channel <br /> that existed before the mine was constructed. The word "semi-dedicated" also only applies to the <br /> corridor shown on design drawing C-2 and C-3. All stockpiled material to the interior of this corridor is <br /> subject to removal as mine operations dictate, either to relocate said stockpile or to reach the mineable <br /> assets underneath. The integrity of the channel corridor will be maintained (including not permitting <br /> interior flows from flowing into this corridor without accounting for the hydrology) unless the decision is <br /> made to route 100-year flows a different way to the original channel that existed before the mine was <br /> constructed. <br /> The rest of the alignment is actually tied to profile and will be discussed in the profile section. <br /> Profile <br /> Unfortunately,the lay of the land in this part of Metro Denver is steep resulting in slopes in the profile <br /> that lead to super-critical flow. The one solution of allowing for meandering flow cannot be <br /> implemented because it wipes out the operational flexibility of the mine. The other solution is to take <br /> steps to dissipate energy associated with this super-critical flow. This will be discussed further in the <br /> sub-section called "Energy Dissipation". The design channel has the slopes indicated on Drawing C-3 <br /> and provided in Attachment 11. <br /> The lay of the land from the south property line to the house envelopes that now line the southern <br /> border of the mine appear to allow water to flow directly from the mine into said house envelopes. The <br /> design attempts to cut the bottom of the outer ditch below the south property line (up to five feet)to <br /> create a barrier for water flowing in said ditch from flowing over the property line. This necessitated <br /> bringing the profile down at the slopes indicated in Attachment 11 until the flow was directed <br /> westward. Even though Lakewood allows for a curve of 100-foot radius,the design calls for a curve of <br /> 300-foot radius to allow for a straighter approach to a hydraulic jump that will be located right at the <br /> end of the curve. Please note that the slopes along the southern border are all sub-critical until the last <br /> 140 feet where water will be discharged into the original channel that existed before the mine was <br /> constructed. <br /> Cross-Section <br /> The appropriate cross section utilizing a manning's n value of 0.030, and a flowrate of310 CFS for each of <br /> the slopes in Exhibit 11 was calculated utilizing software published by Urban Drainage and Flood Control <br /> (UDFCD 2013).2 The assumption was a channel width of 10.00 feet with side slopes of 4:1,and two feet <br /> 2 The software is no longer offered on the UDFCD website but was given to HMD Water for another project when <br /> requested. <br /> 7 <br /> 9 0 /30/2017 <br />