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Mr. Dave Nettles, P.E. <br />February 13, 2006 <br />Page 3 <br />DESIGN STANDARD <br />Based upon as-built slurry wall alignment records and slurry wall construction records, we <br />calculated the design standard leakage allowed for the Brannan Pit #29 south cell: <br />• The as-built plan indicates the south cell slurry wall liner length is approximately 6,583 <br />feet <br />¦ Based on construction records, the depth to bedrock measured every 100 feet around the <br />site perimeter averages 36.4 feet <br />¦ Design standard liner leakage (per "State Engineer Guidelines for Lining Criteria for <br />Gravel Pits," August 1999) <br />A. Design Standard for Slurry Nall Liner <br />Qallow.wall = 0.03 ft3/day/ft2 x 6583 ft x 36.4 ft <br />Qallow.wall = 7189 ft3/day (or 53,800 gallons/day) <br />Qallow.wall = 37.3 gallons/minute <br />B. Design Standard for Reservoir Floor <br />The area inside the slurry wall in the south cell is approximately 54.9 acres <br />or 2,391,444 ft2 <br />Design standard leakage through the floor of the south cell: <br />Qallow.floor = 0.0015 ft3/day/ft2 x 2,391,444 ft2 <br />Qallow.floor = 3587 ft3/day (or 26,800 gallons/day) <br />Qallow.floor = 18.6 gallons/minute <br />C. Total Design Standard <br />Qtotal = Qallow.wall + Qallow.floor <br />Qtotal = 55.9 gallons/minute <br />The construction standard for a lined reservoir will allow leakage three times this amount (about <br />168 gallons/minute). <br />CALCULATION FOR TEST WATER BALANCE <br />In order to meet the design standard, the test documentation must show that at steady state <br />conditions: