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<br />A Levell investigation does not require any digging or drilling at the project site. A Level
<br />1 investigation must include an examination of existing exposures such as, but not limited to, road
<br />cuts.
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<br />2. Investieation Methods.
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<br />2.1 Literature Survey and Observations. An estimate of the soil/rock profile shall
<br />be made, based on the following geological and pedological literature and maps (required
<br />sources are in bold) information, when available:
<br />2.1.1 USGS 7.5' Quadrangle Topographic Map.
<br />2.1.2 USDA Soil Survey of Lane County Area, Oregon (website:
<br />http://ice.or.nrcs.usda.gov/website/soils/oregonlor _reports _ or.htm).
<br />2.1.3 Historical aerial photos (U of 0 MAP Library).
<br />2.1.4 USGS OM-I10 (Geology of the Southern and Southwestern Border
<br />Areas of the Willamette Valley, Oregon, 1951).
<br />2.1.5 USGS Water Resources Paper 2018 (Groundwater Resources of the
<br />Eugene/Springfield Area, 1973).
<br />2.1.6 USGS 1 :250,000 Geologic Map of the Salem Quadrangle.
<br />2.1.7 Geologic Map of Oregon (USGS, 1991).
<br />2.1.8 Relative Earthquake Hazard Map of the Eugene-Springfield
<br />Metropolitan Area, Lane County, Oregon, IMS-14 Oregon Department of Geology
<br />and Mineral Industries (DOGAMI), 2000.
<br />2.1.9 Records of former City of Eugene, state, and federal public works
<br />projects at or near the proposed development site.
<br />2.1.10 Other sources of information about the site, including geology-based
<br />theses and dissertations prepared by students at University of Oregon or Oregon State
<br />University, studies made by local and regional planning boards, and knowledgeable
<br />individuals such as university professors, reference librarians, geotechnical
<br />engineering firms, engineering geology firms, site exploration firms, local quarry
<br />operators, construction aggregate suppliers, and appropriate persons from agencies
<br />such as State geological surveys, the US Geological Survey (USGS), and the US
<br />Army Corps of Engineers (ACOE).
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<br />2.2 Site Investigation. The site visit shall focus on conditions, such as, but not
<br />limited to, the presence of expansive soil, potential and/or existing instability, shallow
<br />groundwater or surface water, presence of fill, and hazardous materials. The site
<br />reconnaissance shall be performed by a Qualified Registered Professional and include the
<br />following items (as applicable):
<br />2.2.1 Verify topography as indicated on contour map. Measure maximum
<br />slopes using clinometer or equivalent.
<br />2.2.2 Check existing cuts/exposures to determine soil depth, characteristics,
<br />classification and/or rock type/weathering state/depth.
<br />2.2.3 Check for evidence of seeps/springs and vegetation characteristics
<br />2.2.4 Check for evidence of slope movement/creep, including leaning
<br />conifers, pistol-butts on trees, sweeps (long curved sections)on conifers, and
<br />topographic features.
<br />2.2.5 Check performance of any structures, including structures on
<br />adjoining properties, by noting any cracking/uneven pavement, cracked/separated
<br />sidewalks and driveways, uneven roof-lines and/or cracked/separated foundations.
<br />2.2.6 If possible, contact owners/contractors of adjacent lots to evaluate
<br />anecdotal observations of the site and surrounding area in regard to soils, hydrology,
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<br />Administrative Order - 14
<br />R:\ADM INO RD\RULES\03geotech2ao. wpd(03/26/03)
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