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Richard T. Raines <br />March 27, 2009 <br />Page 3 <br />Stagecoach Stop <br />Property 2.9 0 0 1.5 0 1.5 <br />Lupton Lakes 29.9 0 35.3 2.0 0 97.8 <br />TOTAL 51.7 2 35.3 7.4 25.0 151.1 <br />This plan will account for the delayed evaporative depletions from the previously exposed ground <br />water surface area at the Tanabe Pit and Dunes Development. The lagged stream depletions are <br />estimated to total 0.5 acre-feet for the Tanabe Pit and 1.5 acre-feet for the Dunes Development during <br />the term of this approval. <br />Note, that due to a change in administration of evaporation from ground water exposed to the <br />atmosphere prior to 1981, pre-1981 credits will no longer be allowed for gravel pits which exposed ground <br />water to the atmosphere prior to 1981 and were actively mined on or after January 1, 1981. Accordingly, <br />evaporative depletions for such gravel pits will need to be replaced from the entire surface area of the <br />ground water exposed in the pits. In order to allow owners and operators of the affected pits time to <br />comply with this change in the administration requirements, the owners and operators will have until <br />January 1, 2010 to comply with the replacement requirements. If the area included in the DRMS mining <br />permit site contains individual gravel pit ponds that were not altered or mined after December 31, 1980, you <br />may still be able to maintain the "pre-81" credit provided you can document when mining in the individual <br />ponds ceased. The Applicant is hereby notified that in accordance with the above described change <br />in administration, the evaporation from ground water exposed prior to 1981 must be replaced after <br />January 1, 2010 in any subsequent SWSP renewal for Howe Pit. <br />A slurry wall has been installed around the Stagecoach Stop Property so that the site will be <br />sealed from the tributary groundwater. All process water for the Stagecoach Stop Property will be <br />pumped from well no. 63864-F which is located inside the mining permit boundary but outside of the <br />slurry wall. The water from the well will be pumped into a small lined wash pond inside the slurry wall <br />lined pit. The SWSP request assumes that the process water is 100% consumed. However as <br />mentioned above this site was sold to Albert Frei and Sons therefore Lafarge will not make <br />replacements for this site after March 2009. The replacement requirement for this site beginning in April <br />2009 will be the responsibility of Albert Frei and Sons. <br />Lupton Lakes site will exposed a maximum of 10 acres during the period of this plan. This site <br />was dewatered from May 2008 through September 2009. The lagged depletions after the dewatering <br />stopped from November 2008 through October 2009 equal 47.9 acre-feet. As long as the pit is <br />continuously dewatered, the water returned to the stream system should be adequate to offset the <br />depletions, however once dewatering at the site ceases, the river will experience a net depletion as the <br />pits gradually fill. The Applicant is hereby notified that if dewatering at this site occurs only during <br />the summer months and the pond is allowed to fill during the winter months the depletions that <br />will have an effect on the stream as a result of refilling the pit, must be addressed in any <br />subsequent SWSP renewal for this pit. <br />The mining sites are set back from the river, therefore, the depletions from the operations were <br />not assumed to be instantaneous. Operational and evaporative depletions at the site were lagged to the <br />stream system using a Glover analysis and the aquifer parameters shown below: <br />Site Name X ft W ft T( d/ft Specific Yield <br />Howe Pit 350 12,000 45,000 0.2 <br />Tanabe Pit 4,200 6,700 115,000 0.2