8920 EVERGREEN WAY THE RESERVE 2025-07-25

Zipper Geo Associates, LLC Reserve at Everett Project No.1117.01 May 1,2013 Soil Conditions The subsurface evaluation for this project included 10 test pits (TP-1 to TP-10). The test pits were advanced to depths ranging from about 4 to 16.5 feet below existing site grades using a track-mounted excavator. The approximate exploration locations are shown on the Site and Exploration Plan, Figure 2. Soils were visually classified in general accordance with the Unified Soil Classification System. Descriptive logs of the subsurface explorations and the procedures utilized in the subsurface exploration program are presented in Appendix A. A generalized description of soil conditions encountered in the test pits is presented below. Detailed descriptions of soils encountered are provided on the descriptive logs in Appendix A. Soils encountered in the test pits completed generally consisted of a surficial layer of forest duff and topsoil ranging from 6 inches to two feet thick. However,3 inches of concrete underlain by about 5 inches of pea gravel was encountered directly below the surface in test pit TP-9. Below the surficial layers, soils encountered in the tests pits generally consisted loose to medium dense,wet to saturated, silty sand with some gravel (weathered Glacial Till)extending to about 2 to 5 feet below existing site grades. However, in local areas (TP-2, TP-4) a thin layer of variable fill was encountered directly below the forest duff and topsoil. Below the fill in these test pits,weathered Glacial Till was encountered. Soils encountered below the weathered Glacial Till in all the test pits generally consisted of dense to very dense, moist to wet, gravelly, silty sand (Glacial Till). However, in test pit TP-5 at about 12 feet below existing site grade (approximately elevation 546 feet), a two foot layer of fine sand with some silt underlain by sandy gravel with trace silt was encountered below the Glacial Till. The sandy gravel was encountered to the completion depth of about 16.5 feet below existing site grade. Heavy groundwater seepage and caving of the test pit sidewalls was observed below 12 feet in test pit TP-5. Similar conditions were observed in test pit TP-6 from about 7 to 10 feet below existing site grade. Groundwater Conditions Groundwater was observed in test pits TP-4 through TP-6, TP-7, TP-9 and TP-10. In test pits TP-4 through TP-6, moderate to heavy groundwater seepage was observed at about 7 to 16.5 feet below existing site grades(approximately elevations 540 to 546 feet). Groundwater observed in these test pits is interpreted to be a shallow, local confined aquifer of unknown thickness. Test pits TP-4 through TP-6 were completed to a minimum elevation of about 537 feet. A lower groundwater confining layer was not encountered down to elevation 537 feet. In test pits TP-7, TP-9 and TP-10, groundwater was encountered at about 2 to 3 feet below existing site grades. Groundwater encountered in these test pits is interpreted to be a thin layer of saturated soils at the bottom of the weathered glacial till unit. Fluctuations in groundwater levels will likely occur due to seasonal variations in the amount of rainfall, runoff and other factors not evident at the time the explorations were performed. Therefore, groundwater levels during construction or at other times in the life of the structure may be higher than Page 3