Agenda - Council - 10/26/2021 - Laserfiche WebLink

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5.3 Backfill and Fills Site soils that will be excavated and reused as backfill and fill appear to be below their assumed optimum moisture content. We anticipate it may be necessary to moisture condition (wet) these soils to achieve the recommended compaction. We recommend that fill and backfill be placed in lifts not exceeding 4 to 12 inches, depending on the size of the compactor and materials used. 5.4 Testing We recommend density tests of backfill and fills placed for the proposed roadway and utilities. Samples of the proposed materials should be submitted to our laboratory prior to placement for evaluation of their suitability and to determine their optimum moisture content and maximum dry density (Standard Proctor). 5.5 Winter Construction If site grading and construction is anticipated to proceed during cold weather, all snow and ice should be removed from cut and fill areas prior to additional grading and placement of fill. No fill should be placed on frozen soil and no frozen soil should be used as fill or backfill. Concrete delivered to the site should meet the temperature requirements of ASTM and/or ACI. Concrete should not be placed on frozen soil. Concrete should be protected from freezing until the necessary strength is obtained. 6.0 PROCEDURES 6.1 Soil Classification The drill crew chief visually and manually classified the soils encountered in the borings in general accordance with ASTM D 2488, "Description and Identification of Soils (Visual -Manual Procedure)". Soil terminology notes are included in the Appendix. The samples were returned to our laboratory for review of the field classification by a soils engineer. Samples will be retained for a period of 30 days. 6.2 Groundwater Observations Immediately after taking the final samples in the bottom of the borings, the holes were checked for the presence of groundwater. Immediately after removing the augers from the borehole the holes were once again checked and the depth to water and cave-in depths were noted. 7.0 GENERAL 7.1 Subsurface Variations The analyses and recommendations presented in this report are based on data obtained from a limited number of soil borings. Variations can occur away from the borings, the nature of which 11