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Page � 3 Recommendatio s Soil Bearing Capacity Based on the result of our soil bo ings it is our opinion that the wall can be supported on the native lean clay or sandy lean clay or compacted engineered fill following removal of the organic clays. It is further our opinion th t a net allowable soil bearing pressure up to 2,000 pounds per square foot(ps�can be used for wall esign. Wall Drainage We recommend backfill adjacent to the w 11(s) with sand having less than 50 percent of the particles by weight passing the #40 sieve and les than 5 percent of the particles by weight passing the #200 sieve. The sand backfill should be plac d within at least 1 foot horizontally of the wall. We recommend using a friction angle of 32 degree and a unit weight of 120 pound per cubic foot(pc fl for this material. Soil Backfill Standard Proctor tests were performed o samples of the on-site soils. Result of the Proctor tests yielded maximum dry densities ranging fr m about 98 to 115 pounds per cubic foot (pc fl with corresponding wet (total maximum) densit es of 115 to 129 pcf, respectively. We recommend using a friction angle of 28 degrees and a u it weight of 125 pcf for the on-site clayey soils for wall design. Compaction Since the walls are strictly landscaping wal it is our opinion that the wall backfill can be compacted to a minimum of 90 percent of its standard Proctor density (ASTM D 698). Fill should be placed within 5 percentage points above and 1 perc ntage point below its optimum moisture content as determined by the standard Proctor. All 'll should be placed in thin lifts and be compacted with a vibratory compactor. Summary The soils below Wa111 appear suitable for the recommen bearing capacity of 2,000 psf. The backfill soil observed generally appeared to meet the recommend d 90 percent compaction. We understand Wall 2 with be reconstructed to be le s than 4 feet tall and therefore, it is not required to be engineered. General The hand auger borings were completed using a 3 inch d meter bucket type auger. The hand auger was advanced in 3 to 6 inch increments. The sampl recovered were visually and manually classified in accordance with ASTM Test Method D 2488. chart explaining the classification system is attached. Haugo GeoTechnical Services does not practice in the fi d of surveying therefore the locations and elevations referenced or described above should be consi ered approximate. 1 3570 GROVE DRIVE �'278! APLE GR�VE� MN 5531 1