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parameters recommended in the attached Table 1 and the Spencer - Wright method to <br />analyze the two cases presented: 1) `Pit Side Flood,' an d 2) the dewatered condition. <br />The staff found all analyzed failure surfaces for the Pit Side Flood to have a Factor of <br />Safety (FoS) very near or greater than 1.1. However, when the staff analyzed the <br />dewatered condition, several failure surfaces were found to have a FoS below 1.0 and <br />some surfaces originating as far as 26 feet from the slope crest with a FoS less than <br />1.1. Given the uncertainty in the soil properties and the water table, the proposed 25- <br />foot setback must have a FoS of at least 1.1 in critical areas such as the gas wells. <br />Please revise the mine plan and provide slope stability analyses to demonstrate the <br />revised mine plan will result in a FoS of at least 1.1 in critical areas. <br />Please refer to attached correspondence from C.G.R.S. of 28 June 2011. <br />Attachments: <br />1 Proof of Placement of this material with the Weld County <br />Clerk to the Board. <br />2 C.G.R.S. correspondence of 28 June 2011. <br />Varra Companies, Inc. correspondence of 29 June 2011 to the Colorado Office of Mined Land Reclamation 4 <br />(OMLR) in reply to OMLR correspondence of 21 June 2011— Western Sugar Reclamation Land Development <br />Project — M- 2010 -049. <br />