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Andy Rodriguez, P.E. <br />September 30, 2009 <br />Page 2 <br />Dewatering of the site commenced in October 1998 at a rate of 300 gallons per minute <br />and continued through December 2007. The SWSP accounts for the depletions to the stream <br />system that result from the past dewatering at the site. <br />The depletions from evaporation, water removed in product, dust suppression, concrete <br />batching and dewatering were lagged to the stream system using a Glover analysis and <br />assuming a distance to the no flow boundary of 10,000 feet, distance of the well to the river of <br />5,409 feet, transmissivity of 72,300 gpd/ft and specific yield of 0.2. <br />Replacements <br />The proposed source of replacement for this pit is fully consumable water leased from <br />the City of Longmont ("Longmont") and 1 share of Rural Ditch. <br />The 1 share of Rural Ditch is a portion of 3.5 shares that were historically used to <br />irrigate 125 acres, in combination with the Mayfield Seep. Historically the 125 acres supported <br />alfalfa, corn silage, sugar beets, pasture grass, beans and barley. Assuming a 20% ditch loss <br />and a 65% irrigation efficiency, the dry-year consumptive use of the 3.5 shares of Rural Ditch <br />was determined to be 176.4 acre-feet. Therefore, the prorata consumptive use of the 1 share <br />of Rural Ditch claimed under this plan is 50.4 acre-feet. <br />The Applicant has obtained a lease with Longmont for 127.75 acre-feet of fully <br />consumable effluent for the period ,of January 2009 through October 2009. The City of <br />Longmont wastewater treatment plant is located approximately 8.15 miles upstream of this <br />existing mining operation. A 0.5 percent per mile transit loss (4.075 percent overall loss) has <br />been accounted for in the replacements. <br />A monthly breakdown of depletions and replacements is shown in the attached Table <br />No. 7. <br />Conditions of Approval <br />I approve the proposed substitute water supply plan in accordance with Section 37-90- <br />137(11), C.R.S., subject to the following conditions: <br />1.. This SWSP shall be valid for the period of January 1, 2009 through October 31, 2009, <br />unless otherwise revoked, modified, or superceded by decree. This plan will be <br />extended until December 31, 2009, if the applicant submits a lease from the City of <br />Longmont for the period of November 1, 2009 through December 31, 2009 prior to <br />October 15, 2009. If this plan will not be made absolute by a water court action by the <br />plan's expiration date, a renewal request must be submitted to this office with the <br />statutory fee (currently $257) by October 15, 2009 (November 15, 2009 if extended). <br />2. The total surface area of the groundwater exposed at the Shores pit must not exceed 4 <br />acres during the approval period of this SWSP, resulting in an annual evaporative loss of <br />10.71 acre-feet. <br />3. The annual amount of water used at the operation shall not exceed 3.33 acre-feet for dust <br />control.