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• CONCLUSIONS AND RECOMMENDATIONS <br />GENERAL DISCUSSION <br />No geologic conditions were apparent during our reconnaissance which would preclude <br />the site development as planned, provided the recommendations contained herein are fully complied with. Based <br />on our investigation to date and the knrnvledge of the proposed conswction, the site wndition which would have <br />the gcatcst effect on the planned pond reconswction is the very sVatfied nature of the existing soils and the <br />occupance of boulder sized fragments which are part of the permeable Soil Type I. <br />EXCAVATION Site preparation in all areas to receive structural 811 should begin with <br />the removal of all topsoil, vegetation, and other deleterious materials. Prior to placing any fill, the subgade <br />should be observed by representatives of Lincoln DeVore to determine if the existing vegetation has been <br />adequately removed and that the subgade is capable of supporting the proposed fills. The subgade should then <br />be scarified to a depth of 18 inches, rock Gagnents Beater than 8 inches maximum size should be removed and <br />the soils brought to near optimum moisture conditions and compacted to at least 95% of its maximum standard <br />Proctor dry density [ASTM D-698]. The moisture content of this material should be within + 3% or - 1% of <br />• optimum moisture, as determined by ASTM D-698. Additional material maybe required to properly "choke <br />off' the voids between boulders inthe soils containing large amounts of boulder sized fragments. <br />If eery large amounts of subgrade boulders are suspected in areas or if the integrity of the final wmpacted <br />subgade soils is questionable, it is recommended that a gcotextile fabric be placed on the top of the subgade <br />soils. This gootcxtilc fabric should be designed to act as a filter between the new pond surface soils both in the <br />pond bottom and the pond embankment and the underlying subgade soils in both the pond bottom and <br />embankment areas. This geotextile filter is to function as a barrier to increased piping of the lower subgade <br />soils (Soil T}pe I). The rcconswction of the subgradc soils described above should be sufficient to minimize <br />or prevent future piping unless, very large pockets of boulder fragments are encountered which cannot be easily <br />"chocked ofI" by the reworked subgade soil fill. <br />It is recommended that a minimum of 12 inches but, ideally I8 inches of a mixture of Soil Types I, II and III be <br />placed and compacted as a final pond and embankment liner. The maximum particle size in this final liner <br />should be 4 inches in the longest dimension and the soils should be well mixed. Concentrations or large pockets <br />• or sands or gavels must not be allowed to occur. In general, we recommend alt pond and embanlanent liner <br />