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Report -t�- M$� A(:)I-C'>p 3 1'' r HARDMAN GEOTECHNICAL SERVICES INC. Practical.Cost•Eftective Geotechnical Solutions February 19, 2016 HGSI Project No. 16-1959 Cale Doney Sage Built Homes, LLC 1815 NW 169th Place Suite 1040 Beaverton, OR 97006 caled@sagebuilthomesllc.com 503-969-8298 Via email with hard copies mailed on request Subject: GEOTECHNICAL REVIEW OF FOUNDATION EXCAVATION MURDOCK PARK LOT 3 TIGARD,OREGON As requested, Hardman Geotechnical Services Inc. (HGSI)visited the site to observe surficial soil bearing conditions for the new house being constructed at Murdock Park Lot 3 in Tigard, Oregon. HGSI's scope of work has not included any subsurface exploration or geotechnical engineering prior to construction. HGSI personnel visited the site on February 11 2016 to observe foundation subgrade soils. At the p �' gr time of our site visit the contractor had nearly co pleted the foundation excavation, only a small area in the center of the building footprint was stil being excavated. Foundation bearing soils were evaluated using a steel "T"probe. Exposed soils onsisted of medium stiff to stiff native soil. In one area the contractor had excavated down to ab t 3 feet below grade to overexcavate a zone of old fill. Soils exposed at the base of the overexcavation zone consisted of native silt that is suitable to support the planned foundations. The builder may either backfill the overexcavation zone with compacted crushed rock, or pour taller stem walls in the affected areas. The materials encountered at footing subgrade ele-fations are considered suitable for foundation support. Foundation subgrades as prepared are con idered suitable to support an allowable bearing pressure of 2,000 ps£ Estimated settlement under the allowable bearing pressure is I inch total, and `h inch differential, measured over a horizontal dist T ce of 20 feet. Care should be taken to avoid saturation or disturba ce of footing subgrade soils during and after excavation. If footing bearing soils become saturat or disturbed, any softened soil or slough should be removed and replaced with crushed aggre ate or additional concrete. In general, footing excavations should be cleaned such that no more th about '/� inch of loose soils are present prior to pouring concrete. 10110 SW NImbus Avenue,Suite B-5 Tel(503)530-8076 Portland,Oregon 97223 Mobile(503)575-5634 February 19, 2016 Project No. 16-1959 Construction should include typical measures for controlling subsurface water beneath the homes, including positive crawlspace drainage to an adequate low-point drain exiting the foundation, visqueen covering the exposed ground in the crawlspace, and crawlspace ventilation (foundation vents). The homebuyers should be informed and educated that some slow flowing water in the crawlspaces is considered normal and not necessarily detrimental to the home given these other design elements incorporated into its construction. Appropriate design professionals should be consulted regarding crawlspace ventilation,building material selection and mold prevention issues, which are outside HGSI's area of expertise. We have prepared this report for Sage Built Homes, LLC and it should not be relied upon by third parties without consulting HGSI. Within the limitations of scope, schedule and budget, HGSI executed these services in accordance with generally accepted professional principles and practices in the field of geotechnical engineering at the time the report was prepared. The conclusions and interpretations presented in this report should not be construed as a warranty of the subsurface conditions. No warranty, expressed or implied, is made. O.O We appreciate this opportunity to be of service. Sincerely, HA"mAN GEOTECHNICAL SERVICES INC. 0 PRO I RE F � 9 Q 64 2 l OREGON 01 L. HAR�� EXPIRES: 06-30-20� Scott L. Hardman, P.E., G.E. Principal Geotechnical Engineer 16-1959-Murdock Park Lot 3 fad exc rvw 2 HARDMAN GEOTECHNICAL SERVICES INC.