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Construction Report -West Taylor Pond <br />The original design contained the following five specification items for embankment <br />material and construction procedures. These were adopted from the original <br />geotechnical report presented in Volume 13, Exhibit 7, Part F and are presented below: <br />1) Site Preparation <br />Prior to placing fill the area should be stripped of organic topsoil or other deleterious <br />materials. <br />2) Acceptable Fill Materials <br />Suitable fill materials can be obtained from pond excavations or from nearby borrow <br />sources. Suitable materials include native clay soils, clayey sand soils, and bedrock <br />materials which are broken down to these soil types (SC, GC, CL and CH). bedrock <br />materials should be processed to produce asoil-like material with maximum particle size <br />of 6 inches. The materials used as embankment fill should have at least 25 percent <br />fines (material finer than no. 200 sieve). <br />3) Unacceptable Fill Materials <br />Materials not considered suitable for use as embankment fill include cleaner sand and <br />gravel. Also unacceptable are highly carbonaceous materials obtained from bedrock <br />excavations or well-cemented sandstones which do not break down to soil like <br />material. Highly organic soils or materials containing construction debris are also not <br />acceptable. Frozen soil is not acceptable. <br />4) Fill Placement and Compaction <br />Embankment fill should be placed in thin horizontal lifts (8 to 12 inches loose thickness.) <br />The fill should be moisture conditioned to within 2 percent of optimum moisture content <br />and compacted to at least 95 percent of standard proctor maximum dry density (ASTM <br />D-698). The placing and spreading of fill materials should be started at the lowest point <br />of the embankment. Fill placement and compaction should be observed and tested by <br />qualified geotechnical engineering firm. <br />5) Monitoring and Inspections <br />Monitoring and inspections should be performed by qualified individuals as outlined in <br />CDMG regulations. <br />Following receipt of the laboratory testing, it was determined that the available borrow <br />materials were marginally outside of the range on the plasticity chart for CL materials. <br />Instead, three of the four borrow samples were in the CL-ML category while sample 2P <br />was classified as a ML material. See Attachment 1. After consultation with the <br />geotechnical engineer, the wording of the Item 2 Acceptable fill material was changed <br />as follows to add the final sentence: <br />2) Acceptable Fill Materials <br />Suitable fill materials can be obtained from pond excavations or from nearby borrow <br />sources. Suitable materials include native clay soils, clayey sand soils, and bedrock <br />materials which are broken down to these soil types (SC, GC, CL and CH). bedrock <br />materials should be processed to produce asoil-like material with maximum particle size <br />of 6 inches. The materials used as embankment fill should have at least 25 percent <br />fines (material finer than no. 200 sieve). The field engineer may approve the use of <br />other materials following appropriate laboratory testing. <br />Page 2 <br />