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File No. 20-1008-36 July 14, 1995 should be reduced to 11-1/2 inches of stockpile soils for the sideslope since it will contain 30 percent red clay. A 13-inch lift of stockpile soils should be used in conjunction with the 20 percent Ione clay. C. The 20 or 30 percent imported Granite red clay (by dry weight) shall be spread evenly over the respective uncompacted 13-inch or 11-1/2 inch loose lift. The 20 percent Ione clay (by dry weight) shall be spread evenly over the uncompacted 13-inch loose lift. This should give an uncompacted clay depth of approximately 3 inches for 20 percent red or Ione clay and approximately 4-1/2 inches for 30 percent red clay. As a guide for determining necessary quantities of clay (either red or Ione), a 25-foot by 50-foot square area will require approximately 54 and 76 tons for 20 and 30 percent, respectively. This figure is based on 20 to 22 percent moisture content for both clays, 125 pounds per cubic foot inplace dry density each, and a minimum 12-inches compacted thickness. Modifications to the spread rate may be necessary during construction depending on changes in these parameters. AWL The contractor shall not begin premixing until the Engineer has approved the spreading of red or Ione clay. D. A motorized pug mill mixer capable of injecting water into the mixing chamber at a controlled rate (CMIRS-500 Soil Stabilizer or approved equal) shall be used to initially break the 20 percent imported Ione clay clods only, if used as an alternate, and to mix the soil. The mixer shall have a minimum mixing depth of 16 inches and shall be equipped with "bullet" cutting teeth. The mixing chamber shall be set to a depth of approximately 4 inches, and the mixing bar shall rotate at a minimum speed of 160 rpm. A minimum of one pass (premixing) shall be made with the mixer without adding any moisture to break the 20 percent imported Ione clay clods. A CMI RS 500 Soil Stabilizer shall use a minimum of one premixing pass for Ione clay only. Premixing shall continue until a maximum of 10 percent is retained on a 3/4-inch sieve. Cobbles and cemented particles larger than 2 inches, and foreign material, shall be removed by the Contractor. Premixing is not necessary if Granite red clay is used. E. After premixing Ione clay, or when using Granite red clay, the mixing chamber shall be set to a depth adequate to mix the 13-inch stockpile soil layer with the 3-inch 20 percent Granite red or Ione clay layer or the 11-1/2-inch stockpile soil layer with the 4-1/2-inch 30 percent Granite red clay layer. Caution should be taken as not to mix the material with the foundation layer. A minimum of one pass shall be made with the mixer without adding any moisture to mix the 20 to 30 percent clay with the 80 or 70 percent stockpile soil, GSM.-md CH195 Page 22 of 31 July 14, 1995 20-1008-36(CQACOR) Copyright 1995,Kleinfelder,Inc.