7725 EVERGREEN WAY BASE FILE 2016-01-01 MF Import

� !9e recommend that drains be placed around all exterior perimeter footings. The drains should be constructed w:.th a four inch diameter perforated PVC pipe bedded and covered with fr.=e draining gravel. The drains should have 3 positi�ve gradient towards suitable discharge facilities. The footing drainage system should not be tied into the roof drainag� system. �e footing excavation should be Y,ackfilled with granular s�il except for the top foot which should be backfilled with a relatively impermeable soil such as silt, clay or topsoil. Alternately, the surface can be sealed with asphalt or concrete pavements. Slab-on-Grade Floors Slab-un-grade floore should be supported on tne dense native till soil or on structural fill. It is recommended that in the eastern site area, where existing fill soils are present, that the slab be founded on a minimum of one foot of structural fill. �y disturbed native soils must be either recompacted or replaced with structural fill. The slab should be provided with a minimum of four inches of free draining sand or gravel. In areas �vhere moisture is undesirable, a vapor barrier such ?s a 6 mil plastic membrane should be placed beneath the slab. Two inches of sand may be placed over the membrane for protection during construction and to aid in curing of the concrete. Site=� Groundwater was encountered in our borings at depths rangi.ng from five (5) to set-enteen (17) feet. However, it has been our experience that grounnwater levels change significantly due to changes in rainfall amounts, surface drainage and other factor;. If seepage is encountered in any excavation, the water should be drained away from the site by use of ditches, perforated pipe, French drains, or by pumping from sumps. We suggest that appropriate locations of subsurface drains be established during grading operations by a representative of Earch C�nsultants, Inc., � _. _ . _ _ _._.. .�...,r