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Report G EODESIGNz i t c / 7S-Th Arc- FIELD REPORT Page 1 of 2 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 (10/23/15) 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, I observed NEI crews were backfilling and compacting a storm water line on the north side of lot 72. The storm line was 2 %z 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 co of%"-0"crushed rock procured from Northfork- Eaton. I used a Troxler 3430 nuclear density gauge to evaluate the o 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 6' Standard proctor (ASTM D698), while below 4' be compacted to at least 90%. 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. 0 V 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. 2 Sanitary Sewer Trench Backfill Upon my arrival, Dallas with NEI had prepared the bottom lift of a section of sanitary sewer trench on 172^d. I used a o nuclear density gauge to evaluate the trench. Multiple areas did not meet minimum compaction requirements. a.; Dallas said that they would recompact the trench. Upon my return to the site, I retested the areas that did not meet 0 co compaction with some areas still not meeting compaction requirements. Dallas informed me that they would moisture condition and recompact. a. 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. a: CO CO U 15575 SW Sequoia Parkway,Suite 100 I Portland,OR 97224 I Off 503.968.8787 I Fax 503.968.3068 x 0 0 X •.• a G EODESIGNuz FIELD REPORT Page 2 of 2 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%" 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: Attachments: Site Plan (1), NDGD(1) ? Reviewed by: / „,4 cti This report presents opinions formed as a result of our observation of activities relating to ge• •ineering or environmentaleBvlces.Weon the contractor to comply with the plans and specifications throughout the duration of the project irrespective of the presence of our repre r work does not include'supervision or d of the "tractor,U a,e Ktr81tor's employees to or agents. Our firm is not responsible for site safety.This field report is a DRAFT representat Id observations, •,and preliminary recommen .Th port 6nly be CO considered final upon review of the GeoDesign project manager,as Indicated by Initials in the section.• /fcap Sid Q o. � c m 0 as as 0 +,o 2 co N r` co a CC co co15575 SW Sequoia Parkway,Suite 100 I Portland,OR 97224 I Off 503.968.8787 I Fax 503.968.3068 x 0 a� X