7710 EVERGREEN WAY NEW CINGULAR WIRELESS ANTENNA 2016-09-26

Adapt Engineering foundation options be evaluated and the most suitable foundation system be selected based on economic and other construction considerations. For planning purposes, we have therefore provided design criteria for compressive, uplift and lateral support of both a drilled pier and concrete mat foundation option below. Our specific recommendations concerning site preparation, equipment building or cabinet foundations, tower foundations, access driveway, and structural fill are presented in the subsequent sections. Site Preparation Preparation of the lease area for construction should involve clearing, grubbing, stripping, cutting, filling, dewatering, and subgrade preparation. We provide the following comments and recommendations relative to site preparation. Temporary Draina�e: We recommend intercepting and diverting any potential sources of surface or near-surface water within the construction zones before stripping begins. Because the selection of an appropriate drainage system will depend on the water quantity, season, weather conditions, construction sequence, and contractor's methods, final decisions regarding drainage systems are best made in the field at the time of construction. Nonetheless, we anticipate that curbs, berms, or ditches placed along the uphill side of the work areas will adequately intercept surface water runoff. Clearin� and Stripping: After surface and near-surface water sources have been controlled, the construction areas to be developed should be cleared and stripped of all asphalt, vegetation, sod, topsoil, and debris. Our exploration indicates an average thickness of 2 to 3-inches of asphalt surfacing materia] mantling 1 to 2-feet of sand, gravel, crushed rock, and rock spalls, interpreted as fill material used as a grading course, across the site, but significant variations could occur elsewhere at the time of construction. It should also be realized that if the stripping operation proceeds during wet weather, a generally greater stripping depth might be necessary to remove disturbed, surficial, moisture-sensitive soils; therefore, stripping is best performed during a period of dry weather. Excavations: Site excavations ranging up to 4-feet deep are anticipated to accommodate the proposed equipment pad footings, and for the tower mat foundation, if selected. Based on our exploration, we anticipate that these excavations will encounter fill soils over very dense fine to coarse sand with silt. We anticipate these surficial soils can be cut with conventional earth working equipment such as small dozers and trackhoes. Backfill materials, where required, should be placed and compacted according to recommendations presented in the Structural Fill section of this report. Temporary Cut Slopes: All temporary soil cuts (greater than 4 feet in height) associated with site excavations ar re-grading activities should be adequately sloped back to prevent sloughing and collapse, unless a shoring box or other suitable excavation side wall bracing is provided. We tentatively recommend a maximum cut slope inclination of 1.SH:1 V(HorizontaL•Vertical) within the very dense sands, gravels, and crushed rock/rock spalls that will likely be exposed within the upper 4-feet below the ground surface across the site. If groundwater seepage is encountered within the excavation slopes, the cut slope inclination may need to be flatter than 1.SH:1 V. However, appropriate inclinations will AT&T Mobility Go Ryka Consulting May 5, 2014 Adapt Project No. WA14-18929-GEO Page 4