HomeMy WebLinkAbout20160674E002 Bethany Corner 2021-03-29 FR 004.pdf
Kirkland | Tacoma | Mount Vernon
425-827-7701| www.aesgeo.com
Date Mailed:
Principal / PM: Matthew A. Miller, P.E.
This document is considered a DRAFT until signed or initialed by an AESI Principal or Project Manager
Page 1 of 4
v.7.20
FIELD REPORT
Date Project Name Project No. Report No.
2021-03-29 Bethany Corner 20160674E002 004
Location Municipality AESI Project Manager AESI Field Rep
16451 111th Ave SE Renton Matthew A. Miller, P.E. Zach Skelton, E.I.T.
Permit No. Client/Owner Attn Requested By
Mark Seek (Tiger Mountain Homes) Mark Seek Client
Engineer/Architect General Contractor Grading Contractor Weather
D.R. Strong Tiger Mountain Homes / Mark Fury Site Works P. Cloudy 40’s
THE FOLLOWING WAS NOTED:
Associated Earth Sciences, Inc. (AESI) arrived on site at approximately 11:15 am and stayed until approximately 2:30 pm at
the request of the contractor to observe sanitary sewer main and side sewer backfill. While on site we met with Mark
Seek with Tiger Mountain Homes and representatives of Fury Site Works.
Sanitary Sewer Main and Side Sewer Backfill
Prior to our arrival, Fury had completed approximately 60 feet of sanitary sewer main, placed the first section of MH
1381-2, and covered this area with pea gravel. While on site, AESI observed the contractor excavate a trench up to
approximately 6 feet below surface elevation for the Lot 1 side sewer. Fury installed a 6-inch T600 PVC pipe in this trench
and bedded and covered it in approximately 3 inches and 12 inches of pea gravel, respectively. AESI observed while the
contractor backfilled this trench with imported gravel borrow. Gravel borrow consists of a brown-gray coarse sand and
gravel with trace silt. Compaction was achieved with a CAT 315C L tracked hoe pac. Compaction tests were performed at
depth. Figure 1 shows the area of sanitary sewer main and side sewer observed by AESI today. Table 1 shows the results
of compaction tests performed by AESI today. Per Soos Creek Water & Sewer district, a minimum of 90% compaction is
required for areas 3 feet below grade or deeper and a minimum 95% compaction is required for areas shallower than 3
feet below grade (see Figure 2).
While on site, Fury and Mark Seek inquired about using native material to backfill the sewer trenches. AESI observed
stockpiles of two materials near the sewer trench. One stockpile consists of a brown-gray silty sand with some gravel (till)
and the other consists of a tan-brown sand with some silt and trace gravel. AESI measured the moisture content of these
two stockpiles with a Troxler nuclear densometer gauge. Measurements indicated elevated moisture content in these two
stockpiles and AESI recommended against using these materials as backfill in their current conditions.
AESI intends to return tomorrow to continue monitoring side sewer and sanitary sewer main backfill.
Table 1: Compaction Results of Tests Taken Today
Test Location
Depth below
grade (ft)
Dry Density
(pcf) M %
Proctor (pcf),
ASTM D: 1557 Opt.M% %Compaction Pass/Fail*
1 Sewer, Figure 1 6 129.0 6.9 141.3 7.7 91 Pass
2 Sewer, Figure 1 3 131.1 7.9 141.3 7.7 93 Pass
*Minimum 90% compaction required for tests deeper than 3 feet or deeper, minimum 95% compaction required for tests shallower than 3 feet.
Date Project Name Project No. Report No.
2021-03-29 Bethany Corner 20160674E002 004
Page 2 of 4
FIELD REPORT
Figure 1 – Location of sewer observed by AESI today shown in red. Approximate locations of compaction tests shown in
yellow.
NN
MH 1381-2
2
1
Date Project Name Project No. Report No.
2021-03-29 Bethany Corner 20160674E002 004
Page 3 of 4
FIELD REPORT
Figure 2 – Trench detail from Soos Creek Water & Sewer District showing compaction requirements.
Date Project Name Project No. Report No.
2021-03-29 Bethany Corner 20160674E002 004
Page 4 of 4
FIELD REPORT
Figure 3 – Sanitary sewer main and side sewer trenches observed by AESI today.