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<br />Sira W. Sartori <br />October 27, 2009 <br />Plan Operation <br />Page 2 <br />According to the current SWSP request the Howe Pit, Mann Lakes Pit, and the Fort Lupton <br />Lakes are active mining sites and the Fort Lupton Pit is an inactive reserve sites which Lafarge will <br />resume mining once it is economically feasible. The gravel pits are located as shown on attached Figure <br />1. <br />This plan identifies replacement sources to cover depletions from the multiple mine sites. The <br />following table lists the sites that are involved in this combined replacement plan: <br />TABLE A - COMRINF11 RFPI ArFAAFMT PI Any cITNQ <br /> <br />Site Name <br />DRMS # Previous Current <br />Well Permit New Permit Exposed Surface <br /> Approval No Required (acres) <br />Howe Pit M-78-052 03/27/2009 67261-F No 26.6-pre-81 <br />Mann Lakes M-82-147 03/27/2009 56354-F No 0.0* <br />Ft. Lupton Pit M-85-088 03/27/2009 55577-F No 4.0 <br />Lupton Lakes M-04-078 03/27/2009 66625-F No 10 <br />urnng was approved on September 10, 2009 <br />Depletions <br />The total annual losses resulting from evaporation, water lost in product, dust control and <br />concrete batching are shown in the following table: <br />TABLE B - LOSSES <br /> <br />Site Name Evaporation <br />Losses <br />(ac-ft) Lost in <br />Product <br />(ac-ft) Dust <br />Control <br />(ac-ft) Concrete <br />Batching <br />(ac-ft) Total <br /> <br />(ac-ft) Total <br />Lagged <br />(ac-ft) <br />Howe Pit 0 0 0 25.0 25.0 25.9 <br />Mann Lakes 0 0 0 0 0 1.1 <br />Ft. Lupton Pit 11.7 0 0 0 11.7 11.7 <br />Lupton Lakes 29.9 35.3 42.6 0 107.8 113.5 <br />TOTAL 41.6 35.3 42.6 25.0 144.5 152.2 <br />Lafarge does not anticipate dewatering any of the sites during the period of this SWSP. Lupton <br />Lakes site was dewatered from May 2008 through September 2008. The lagged dewatering depletions <br />after the dewatering stopped from November 2009 through October 2010 equal 7.5 acre-feet as shown <br />in the attached Table 2. To determine the delayed impact to the South Platte River you estimated that <br />the pond was dewatered at a rate of 1,200 gallons per minute and decreasing to 200 gallons per minute <br />for 8 hours a day, 365 days a year. <br />As long as the pit is continuously dewatered, the water returned to the stream system should be <br />adequate to offset the depletions, however once dewatering at the site ceases, the river will experience <br />a net depletion as the pits gradually fill. At least three years prior to completion of mining, a plan must be <br />submitted that specifies how the post pumping dewatering depletions (including refilling the pit) will be