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G DESIGNS !it l 7 �3 S FIELD REPORT
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GDI Project: Polygon-123-03 Prepared By: Daniel Stai
Project Name: West River Terrace Date: February 9`h , 2016
Location: SW Roy Rogers Road, Tigard Report#: 25
Arrival: 1000; 1545 Departure: 1200; 1730
Weather: Sunny, 60's Permit#: TBA
Site Visit Requested By: Jason (NEI) Met With (on site): Jason; Dallas (NEI); Mike Via
Phone (Polygon)
Purpose: Observe and Evaluate Utility Trench Backfill and Evaluate Lot Subgrades
Outstanding Issues: FR 16 & 17 (10/21 & 10/22) Areas of fill with low density and high moisture contents in
lots 1-9, 53 72, & 78-82 *PARTIALLY RESOLVED* FR18
FR18 (10/23/1 5) Minor pumping in lots 53-72
FR 21 (02/02/16) Low density in trench backfill
FR 25 (2/9) Low density sanitary trench backfill locations
Storm Water Trench Backfill
Upon my arrival on site, l observed NEI crews were backfilling and compacting a storm water line on the north side
of lot 72. The storm line was 21/2 to 4' deep along the run. NEI had also prepared the top lift of a section of trench
along SW Sabrina Avenue. Compaction was achieved using a large diesel plate compactor. Trench backfill consisted
of 3/4"-0" crushed rock procured from Northfork- Eaton. I used a Troxler 3430 nuclear density gauge to evaluate the
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density of the trench backfill. Tests were compared to a laboratory determined standard proctor(ASTM D698) of
124pcf at an optimum moisture content of 15%.The top 4' of trench should be compacted to at least 95%of a
Standard proctor (ASTM D698), while below 4' be compacted to at least 90%.
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All areas of the storm water trench, where tested, met or exceeded compaction. See attached nuclear density gauge c�
datasheet and site plan for details. `o
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NEI had also prepared the bottom lift of storm water trench that runs north of lots 78-82. The area had been sloped
back and I could safely test approx. 6' below finish grade. Compaction had been achieved using a hoe pack and/or o
a walk behind diesel plate compactor. All tested locations met compaction requirements at 6'. Upon my return to
the site in the afternoon, NEI had placed and compacted another 2' of crushed rock fill. All tested locations met or
exceeded compaction requirements.
Sanitary Sewer Trench Backfill o
Upon my arrival, Dallas with NEI had prepared the bottom lift of a section of sanitary sewer trench on 172''. I used a o
nuclear density gauge to evaluate the trench. Multiple areas did not meet minimum compaction requirements.
Dallas said that they would recompact the trench. Upon my return to the site, I retested the areas that did not meet
compaction with some areas still not meeting compaction requirements. Dallas informed me that they would
moisture condition and recompact. u_
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Based on observations, the areas of trench backfill evaluated today (excluding areas of low density), and indicated
on the attached site plan and nuclear density data sheet, were prepared in general accordance with project
requirements and our geotechnical recommendations. cr
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oo15575 SW Sequoia Parkway,Suite 100 I Portland,OR 97224 I Off 503.968.8787 I Fax 503.968.3068 0
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GEODESIGNV. FIELD REPORT
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Evaluate Lot Subgrades
Mike with Polygon asked me to evaluate the subgrade in lots 38, 52, 96, & 97 while on site. All lots had been cut
down to a relatively flat elevation and covered with 1 to 2" of loose crushed rock to protect subgrade. I used a W
diameter steel "T" probe to evaluate consistency of subgrade. Lots 38, 52, & 96 generally appeared to be stiff based
on resistance to penetration of the probe. I observed that lot 97 appeared to have two areas with medium stiff soils
at the surface that transitioned to stiff soil and probe refusal at 6 to 18" deep.
Based on our observations, the lot subgrades probed today have been prepared in general accordance with project
requirements and our geotechnical recommendations.
Distribution: R •,
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Attachments: Site Plan (1), NDGD (1)
Reviewed by: / ,\r)
This report presents opinions formed as a result of our observation of activities relating to geote gineering or environmental snces. We rely on the contractor to comply wtth the plans and
specifications throughout the duration of the project irrespective of the presence of our repres Jl: ,t ur work does not include'supervision or direction of the contractor.thecofitrkttor s employees
or agents- Our firm is not responsible for site safety. This field report is a DRAFT representat• ''eld observations,testing,and preliminary recommendttecns. The report can Only be
considered final upon review of the GeoDesign project manager,as indicated by initials in the" section. .' f //,!
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