1632 46TH ST SE 2020-06-18 - Laserfiche WebLink

July 3, 2017 Single-Family Residence L&A Job No. 17-079 Page 4 the last glaciation period. Due to their generally granular composition, the advance outwash deposits are of moderately high permeability and drains fairly well. The advance outwash deposits had been glacially overridden and are generally dense to very-dense in their natural, undisturbed state, except the top 2 to 3 feet of soils exposed on slopes which are normally weathered to a loose to medium-dense state. The underlying fresh advance outwash deposits can stand in natural slopes or steep cuts for extended period when undisturbed and properly drained. Where exposed on slopes devoid of vegetation cover and subject to storm runoff or groundwater seepage, the advance outwash deposits can be gradually eroded and may slough and redeposit to a flatter inclination. The fresh advance outwash deposits are also quite stable and capable of providing very good foundation support with little settlement. The deposits of the transitional beds soil unit are composed of glacial and non-glacial deposits of interbedded silt, fine sand, occasional gravel, and diamicts of indeterminate age and origin. These deposits are generally very-stiff to hard and are of extremely low permeability in their native undisturbed state. When properly drained the transitional beds deposits can remain stable over long period, when saturated the deposits may become unstable and slough off steep slopes or cuts. SOIL CONDITION Subsurface conditions of the project site were explored with three test pits. The test pits were excavated on June 23, 2017, with a rubber-track backhoe to depths from 7.0 to 8.0 feet The approximate locations of the test pits are shown on Plate 2 - Site and Exploration Location Plan. The test pits were located with either a tape measure or by LIIJ & ASSOCIATES, INC.