6605 HARDESON RD BASE FILE 2016-01-01 MF Import

Intracorp Sep:ember 21, 1998 : � : : � . � . � � � � . � � � � E-3592-7Z0 Page 4 Since there is littte to no vegetation or topsoil on the ground surface, strippinp ia not necessary other than for removal of material around the perimeter of the site, if necesaary. Followinp any additional cuts required to provide design grades, the ground surface where structural fill, foundations, or slabs are to be ptaced should be observed by a representative of ECI. Priorto placing the site fills, the existing surface should be proofrotled and compacted with a large vibratory drum roller. Loose or excessively soft areas identified by the roller should be aerated during dry weather and be recompacted, or be overexcavated and replaced with structural fill to a depth that will provide a stable base for the structural fifl. A woven geotextile fabric may also be used to stabilize the overexcavation surface. For tttis application, Mirafi 600X or approved equivalent should be used. Proofro�iinp should be observed by a representative from ECI. Structural fill is defined as compacted fill placed under bufldings, roadways, slabs, pavements, or other load-bearing areas. Structural fill under floor slabs and footings should be placed in horizontal lifts not exceeding twelve (12) inches in loose thickness and compacted to a minimum of 90 percent of its laboratory maximum dry density determined in accordance with ASTM Test Designation D-1557-91 (Modified Proctor). The fill materiais should be placed at or near the optimum moisture contont. Fill under pavements and walks should also be placed in horizontal lifts and compacted to 90 percent of maximum density except for the top twelve (12) inches which should be compacted to 95 percent of maximum density. During dry weather, most soils which are compact(ble and non-organic can be used as structural fill, provided they are near their optimum moisture content. Based on the results of our laboratory tests, the on-site soils at the time of our exploration appeared to be near the optimum moisture content and should be suitable for use in their present condition as structural fill. However, laboratory testing indicates that the soils encountered in the central portion of the site in Test Pit TP-5 were comprised of approximately 50 percent fines passfng the No. 200 sieve. Soils with, g�eater than five percent fines passing the No. 200 sieve will degrade if exposed to excessive moisture, and compaction and erading will be difficult if the soil moistures increase significantly above their optimum conditions. If the site soils are exposed to moisture and cannot be adequately compacted, it may then be necessary to import a soil which can be compacted. During dry weather, any non-organic compactible soil can be used. Fill for use during wet weather should consist of a fairly weli graded granular material having a maximum size of three inches and no more than five percent fines passing the No. 200 sieve based on the minus 3/4inch fraction. A contingency in the earthwork budget should be included for this possibility. ErtA Cawk�n. Ma.