Open-File Report 82-279This report is prelim!inary and has not been reviewed for conformity with U.S. Geological Survey editorial standards and strati graphic nomenclature.Any use of trade names is for descriptive purposes only and does not imply endorsement by the USGS. ABSTRACTTwo holes were hand augered and sampled in ash deposits near Hilo, Hawaii. Color, water content and sensitivity of the ash were measured in the field. The ash alternated between reddish brown and dark reddish brown in color and had water contents as high as 392%. A downhole vane shear device measured sensitivities as high as 6.9. A series of laboratory tests including grain size distribution, Atterberg limits, X-ray diffraction analysis, total carbon determination, vane shear, direct shear and triaxial tests were performed to determine the composition and geotechnical properties of the ash. The ash is very fine grained, highly plastic and composed mostly of gibbsite and amorphous material, presumably allophane. The ash has a high angle of internal friction ranging from 40-43° and is classified as medium to very sensitive.

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