6920 SEAWAY BLVD Geotech Report 2018-01-02 MF Import

I SITC f.0\'DI�CIONS � SURFACE C0�'DITIOhS � The [opogtaph�� uf the :+ro,jec[ site Is [ypically charac[erized by a gently undula[ing ground surface. :\ deeply incised natural drainage feature is loca- ted alung the western edge uf the property. Side slopes along this drainage � range up to as steep as 2: l (horizon[al [o vertical) . The existing manmade lake, which was constructed as par[ of Phase 1 , is t Located southeast of the nev building si[e. This lake is impounded by an I earth dam. Under normal conditions, [he maximum level of [he Lake is con- I [rolled by a weir structure. A rock-lined channel which runs around tl�e north- west end oE tlie earth dam ac[s as the emergency spillway. The discliarge from both the veir structure and ->pillway [luws along a drainage channel w}�ich runs Iin a northerly direction [ovard Seaway Boulevard. A small pond is loca[ed a[ the northern end of this drainage channel. IThe Phase 2 area is currently undeveluped. Most of the site is Yorest�d wi[h fir, alder and ced�r trees. Ground cover consists oE grass, 'erns and Ibrush. SURSURFACE COYDITIOi:S IThe subsurface condiei.o::5 �C the site were explored by driiling b test burings and excavating "LS test pits at Che Locations shown an Pla[e L Ln I addition, hand pro6es were perEormed at various locations across i.1e site to better define the limi[s of soft soils in localized bog areas. A cescription I of [he Pie1d exploration and laboratory testing procedures and the logs of Uie explorations are presented in the Appendix. ?(ust of the site is blanke[ed by forest du[f. I'he Lorest duff is typi- ically un the order of 0.2 to 0.9 feet thick. However, there are occasional trough-Like areas which contain up to about 1� to 2 Eeet of fores[ duf[. ISeveral mounds of Eill ::hich were placed during construction uf the Phase � 1 E.tcili[ies exist in [he Phase 2 area. The loca[ions of some of [he larger , fill mounds are shown on Plate L Test Pit 14 was excavated into Che Ei11. mound located at [he souther❑ end of tlte new buildLng site. The ma[eri.al in this mound consists of soft :,rganic silt with organic matter including Logs. This material ic no[ suttable for use as structural fill. Boring 4 was drilled through the center of the earth dam Eor [he existing manmade lake. 1'he results oE this boring indicate tha[ the dam is composed of meJium dense silty g[avelly fine r_o coarse sand. A thi.n layer of inedium dense I silty gruvelly sand wi[h oreanic matter including compressed peat, aood frag- � � :nents ,�nS roots is present a[ Uie base of [he fill. � GeoEngineers - ' - Incorporoted