1920 MERRILL CREEK PKY 2018-01-01 MF Import

SHANNONF�WILSON INC. I decrease site erosion. Additionally, flattening of select slope a�eas will decrease the risk of local inshability. f ► It is our understanding that the owner has elected to effect slope mitigation f measums within its property limits. In this opdon, we recommend cutting back 1 the near-vertical glacial slopes within the subject property limits only to 1H:1V in till and I.SH:1V in ouhvash. The exisdng heavily vegetated filUcolluvium would I not be disturtr�, as mwement of these soils is unlikely to affect the stability of the upslope development and it was felt that disturbances to these mazginally stable soils could increase the potential for instability. It is understood that there is some risk that surficial mwements of the acisdng slopes could develop in the future due to the marginal stability of the existing filUcolluvial slopes and on-site activities, such as future remaval of exisdng vegehation, or off-site acdvides, such as undercutting the toe of the existing slope by the adjacent property owner. Such surficiai mwements will likely result in the accumulallon of debris at the toe of the existing slope. It is unlikely that these mwements would affect the proposed structure on the upper plateau. It is also recommendeci to pmvide a ditch along the top of the slope to reduce surface groundwater 8ow wer the site. A I discussi�.^. of this alternative is presented in the "Slope Mitigation" sec6on of this report. Slopes zequiring remediation in accordance with this plan are shown on Figure 2. I ► Based on the results of our ezploradons, clearing, grubbing, and stripping should be expected to occur to avecage depths of about 3 feet in building amas to remwe I topsoil, loose fill, and other unsuitable soils; although stripping should procexd w whatever depth is necessary to remwe these soils. I.ess stripping is anticipated in parking and drive areas. i ► The existing fill and weathe�ed nadve soils across the upper plateau of the site would �tquire considerable aeration and/or treatn�ent with lime/cement to facilitate proper wmpacdon. The nadve, till-like soils cculd be reused as structu.-al fill in their present state provided the earthwork is done during dry weather and prwided they azie not disturbed during excavaGon and placement. In wet weather, all of the above-mentioned soils would be unsuitable for reuse as structural 511, I and all-weather fill would have to be imported to the site. Alternadvely, during wet weal,�er, the on-site soit may be treated with cement to facilitate proper Icompaction. . During wnstruction, it will be necessary to undertafoe measures to reduce I disturbance w the subg�ade soils by limidng the passage of tia@ic over them and confining treH'ic to frequently used routes, such as haul roads, among others. During •�vet weather, construction will reyuice a number of other measums, such � as building quarry or crushed rock wnstrucdon pads, placing "rat" or "mud" slabs wer foundations subgrades, and limiting the type and passage of equipment I W-6693-01 9