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Western Dam Engineering Technical Note 6 provides a good reference for this type of information. Table 1 below also summarizes testing methods and associated design considerations for various index properties. Different sample types, volumes, and preparation methods are required for different types of laboratory tests. For example, most index property tests can be performed using disturbed samples (commonly obtained using split spoon or modified California samplers, or by hand from an auger flight, spoil pile or test pit). Conversely, if testing of in-situ properties is desired, engineering property testing such as triaxial shear strength, consolidation, collapse, and permeability tests require relatively undisturbed samples, such as obtained from thin-walled samplers. There are exceptions; for example, strength or permeability tests are often performed on remolded samples to enable modeling compacted embankment fill. Care should be taken to avoid sample disturbance when handling and transporting samples intended for in-situ properties testing from the field to the laboratory. Sample disturbance can significantly affect test results, possibly resulting in mis-characterization of a soil, especially for loose or weaker soils. Laboratory tests, along with the results of field observation and testing, can also be used to identify the properties of special or problematic soils or adverse ground conditions. These can include collapsible soils, dispersive soils, organic soils and peat, expansive soils, slaking shales and degradable soils, sensitive clays, and ground susceptible to fissures. Soil Classification & Description Soil classification is the grouping of a soil into a category, typically using an established system such as the USCS. Soil description is the systematic, precise, and complete naming of individual soils. The soil’s classification and description, as typically provided on a test hole log, should include as a minimum:  Apparent consistency (stiffness for fine- grained soils or density for coarse-grained soils)  Water content condition adjective (e.g., dry, moist, wet, saturated)  Color (e.g., red color can indicate weathered soil, green can indicate organic content)  Plasticity adjective for cohesive soils (e.g., medium plasticity)  Minor and MAIN (capitalized) soil types (e.g., clayey GRAVEL [GC])  USCS Group name and symbol (e.g., GC, GM, GW, GP, SC, SM, SW, SP, ML, CL, SP-SM, etc.)  Inclusions (e.g., trace amounts of other soil types, organic content)  Geologic name, or embankment zone, if known Field engineer’s or geologists make their best determination of the soil classification at the time of drilling and sampling. Final boring or test pit logs are typically checked and adjustments made as necessary based on the results of the laboratory testing. Here is a typical example of a soil description that may be found on a test hole log: “medium-dense, moist, red-brown, silty SAND (SM), trace fine gravel to coarse sand (Alluvium)” Soil descriptions should be provided for each main strata or zone of soil identified in the foundation and embankment. Standard methodology for visual soil classification is provided in ASTM D 2488 – Standard Practice for Description and Identification of Soils Assortment of soil testing equipment: (a) Atterberg Limits, (b) Sieve Analysis, (c) Consolidation, (d) Triaxial Shear a b c d