7000 HARDESON RD 2018-01-02 MF Import

Quadrant 6-917-10280 12 April 1996 Page 2 3.0 SITE CONDITIONS Site conditions for this project were evaluated on 23 through 29 February 1996. The subsurface conditions are described below while the exploration pmeedurasandinterpretive logs of the explorations are presented in Appendix A. The approximate locations of our explorations are presented on the Site and Exploration Plan, Figure 2. 3.1 Surface Conditions Surface conditions currently consist of sparse grass and trees in the southern third of the rough graded site. The northern two-thirds is very thinly vegetated. The hillside to the west is covered with grass and trees. A large fill pile consisting of glacial till is located in the southwestern portion of the site. 3.2 Subsurface Conditions The enclosed.Site and Exploration Plan, Figure 2, shows the locations of borings and test pits completed for this study. We completed a total of sixteen borings and twelve test pits during February and March 1996. The borings were completed with a hollow -stem auger drill rig, with sampling by Standard Penetration Test methods. The borings extended through fill soils into native, undisturbed strata. Three of the borings, designated OW-1, QW-2, and QW-3 were completed as monitoring wells within the upper fill soils at the locations noted on the Site and Exploration Ran. The test pits were completed with a tracked excavator, to depths of B to 15 feet. All of the explorations were logged by an engineering geologist from our firm, and samples were retained for both geotechnical and environmental analytical testing. The explorations disclosed medium dense to dense fill soils to depths of approximately 17 to 35 feet across the entire parcel. The fill soils consisted predominantly of silty, gravelly sand which appeared to originate as glacial till. The fill appeared uniformly compacted across the majority of the parcel, based on SPT blowcounts, with the exception of deeper fill soils along the eastern border of the site. In this area, conditions noted in borings QB-1 through QBA QW-1 through QW-3, and Q13-10 and 08-11, included roughly 10 to 15 feet of medium dense to dense, compacted fill, overlying looser fill soils intermixed with silts. The fill soils with Iintermixed silts appear to be relic settling pond sediment. Blowcounts ranged from approximately 3 to 20 blows per foot within this deposit, and groundwater was sporadically perched within granular soils. Native soils underlying the fill consisted uniformly of dense to very dense sand. Prior explorations encountered a static groundwater table at a depth of about 80 to 90 feet below ground surface at this tie, within the native sand deposit. The relic settling pond sediment was filled prior to 1989 when Hardeson Road design work was being completed by our firm. At the time of our field investigations for Hardeson Road, the location of this relic sediment housed an equipment staging area, operations shacks, and other uses close to existing grades. The timing of the fill placement at this location is not known 5/�