Admin Order 58-02-25-F - Laserfiche WebLink

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Intact Character of Rock: In the Eugene/Springfield area, rock units are Tertiary in age - between 1.64 million years (My) and 35 Myoid. Rock units are classified on the basis of origin, whether igneous (intrusive or extrusive) sedimentary (marine or terrestrial), pYroclastic, or metamorphic; geologic name; color and texture (grain size); hardness; degree of weathering; and if available, degree of fracturing. Pistol-Butt (on Tree): Also called gun-stocked tree. A curved basal section of trunk, resulting from down-slope rotation of the base of the tree. Similar in shape to curved butts on antique side arms. Qualified Registered Professional: An Oregon Registered Professional Engineer (per ORS 672.002 to 672.325), who by training, education, and having a minimum of four years geotechnical experience, is especially qualified to apply the principles of soil mechanics, rock mechanics, hydraulics, and geological science to planning and evaluating engineering site investigations, making appropriate quantitative analyses and engineering design recommendations for that part of civil works involving the use of soil and rock materials and the inspection or testing of the construction thereof; and an Oregon Certified Engineering Geologist (per ORS 672.505 and 672.525), who by training, education, and experience is especially qualified to apply geologic data, principles and interpretation to naturally occurring materials so that geologic factors affecting planning, design, construction and maintenance of civil engineering works are properly recognized and utilized. Representative Disturbed Sampling: Soil samples taken at the site that have been disturbed or altered, completely or partially, by the remolding action of sampling but which contains all of the soil components in their in-situ (original) amounts. Significant Structures and/or Facilities: All pavement structures for arterial and collector streets and all building structures except one and two family dwellings, garages, carports, and outbuildings for one and two family development. Small Project: Examples of small projects are: (a) a utility excavation no more than five (5) feet deep and less than 300 feet long; and (b) road reconstruction, rehabilitation, widening, or extension of less than 300 feet of road in an area with established infrastructure (roads, utilities). Small projects can also include sidewalk construction in an area with established infrastructure. Soil Description and Classification: In the Eugene/Springfield area, soil units are Quaternary in age (younger than 1.64 My). Soil units include fluvial deposits (alluvium) and slope deposits (colluvium). PDS (Partly Decomposed State) and CDS (Completely Decomposed State) rock, although exhibiting characteristics of a soil, should not be classified as a soil unit for the purpose of geological and geotechnical investigation and design reports. Soil materials are described and classified on the basis of ASTM or AASHTO tests for the following properties: origin: whether residual, colluvial, or transported; gradation: measured or estimated grain size distribution; angularity/roundness of visible soil particles; color; measured or estimated in-place moisture content; Atterberg limits: liquid limit, plastic limit, plasticity index of the -40 fraction; relative density if non- plastic or below the plastic limit; consistency if above the plastic limit; Expansion Index; and, Unified Soil Classification System designation, determined by: gradation and Atterberg limits (ASTM D-2487, UBC 18-1 or equivalent) or the Visual Manual Procedure (ASTM D-2488 or equivalent). Administrative Order - 10 R:\ADMINO RD\RULES\03 geotech2ao. wpd(03/26/03)