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Wayzata Country Club Project BL-08-03640 September 29, 2008 Page 6 • Peat and other highly organic soils typically have low shear strengths. They can be easily displaced or disturbed under the loads associated with new fill placed above them. To reduce the potential to "shear"the peat, any new fill should be applied incrementally. We estimate maximum lift thicknesses ranging from 1 to 2 feet. D. Recommendations D.1. Borrow Source The soil borings taken in the potential borrow source area (ST-1,ST-2, and ST-3) encountered granular soils (sands) containing varying amounts of silt and clay as well as varying grain sizes. The sands became "dirtier"with depth,that is, the silt content appeared to increase with increasing depth. At about 14 to 15 feet below the ground surface,the soils consisted mostly of silts. The sandy silt soil identified at depths of about 14 feet and below can be reused as general fill to surcharge the fairway areas. However,these soils are generally moisture sensitive soils;they can be easily disturbed in the presence of moisture and they are typically slow draining materials. The granular soils identified in the upper approximate 12-to 14-foot depths are generally more desirable for use in stabilizing the fairway. These soils are generally more well graded (i.e.,they have a broader range of particle sizes) and will drain reasonably well. In a compacted condition, the sands(SP)and sands with a little silt (SP-SM)are noticeably more rapid draining than the silty sands (SM). Table 2 provides a summary of the estimated depths of granular fill suitable for use/reuse as surcharge material. Table 2. Summary of Depths of Borrow Material Depth of Granular Boring Number Borrow Soil Types ST-1 12 feet Silty Sand (SM) ST-2 12 feet Poorly Graded Sand with Silt (SP-SM) and Silty Sand (SM) ST-3 15 feet Clayey Sand/Silty Sand (SC-SM), Silty Sand (SM), and Poorly Graded Sand with Silt(SP-SM) BRAUN I NTE BTEC