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January 28, 2009 Ms. Jana Ash, P.E. Office of the State Engineer 818 Centennial Building 1313 Sherman Street Denver, Colorado 80203 Re: French Pit, Leak Test Report; D&A Job No. CG-0201.004.00 Dear Ms. Ash: The 90-day leak test for French Pit located in Weld County is complete. Figure 1 shows the vicinity of the pond and the surrounding area. Figure 2 shows the rough graded contours of the pond. The test was performed in accordance with the "State Engineer Guidelines for Lining Criteria for Gravel Pits," August 1999. The test period began on September 29, 2008. The 90-day period ended on December 28, 2008. However, the test was performed for longer than 90 calendar days because of intermittent pumping and ended on January 8, 2009. The pond level was brought back to the same elevation, during each pumping, throughout the test. The leak test followed the work plan as outlined in a letter submitted to your office by Deere and Ault Consultant (D&A) on October 31, 2008. ALLOWABLE LEAKAGE RATES The allowable design leakage rate for French Pit, as calculated by the procedure outlined in the SEO guidelines, is approximately 22 gallons per minute (gpm). The performance standard is three times the design standard or 66 gpm. These numbers are slightly different than the plan submitted to your office on October 31, 2008, because the survey information used in preparing this letter is more accurate than the survey used for the work plan. A summary of the leakage calculations are shown below: L th Average Area Leakage Design Performance* eng (feet) Height (feet) (W) Standard (f?ld ft) Rate told) Rate ( m) Rate ?ld) Wall 2,950 42.7 125,965 0.03 3779.0 19.63 11,336.9 ff Floor 345,359 0.0015 518.0 2.69 1554.1 Total 4297.0 22.32 12890.9 * More significant figures were used in actual calculations than shown