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1 l l j i 1 SAMPLING PROCEDURES Auger Sampling (AS) In this procedure, soil samples are collected from cuttings off of the auger flights as they are removed from the ground. Such samples provide a general indication of subsurface conditions; however, they do not provide undisturbed samples, nor do they provide samples from discrete depths. Split -Barrel Sampling (SS) - (ASTM S2e� cification D-1586-67) In the split -barrel sampling procedure, a 2-inch O.D., split -barrel sampler is driven into the soil a distance of 18 inches by means of repeated blows of a 140-pound hammer falling 30 inches. The value of the Standard Penetration Resistance is obtained by counting the number of blows of the hammer over the final 12 inches of driving. This value provides a qualitative indication of the in -place relative density of cohesionless soils. The indication is qualitative only, however, since many factors can significantly affect the Standard Penetration Resistance Value, and direct correlation of results obtained by drill crews using different drill rigs, drilling procedures, and hammer -rod -spoon assemblies should not be made. Shelby Tube Sampling Procedures (ST) - (ASTM Specification D-1587-67) In the Shelby tube sampling procedure,'a thin -walled, steel seamless tube with a sharp cutting edge is pushed hydraulically into .the soil and a relatively undisturbed sample is obtained. This procedure is generally employed in cohesive soils. Giddings Sampler (GS) This type of sampling device consists of 5-ft sections of thin -walled tubing which are capable of retrieving continuous columns of soil in 5-ft maximum increments. Because of a continuous slot in the sampling tubes, the sampler allows field determination of stratification boundaries and containerization of soil samples from any sampling depth within the 5-ft interval. STS Consultants, Ltd. 1 1 1 1 1 1 1 1 1 1 1 1 i 1 1