HomeMy WebLinkAboutExhibit 11_Geotechnical_Report_Gate_D-50_Modification_170425_v1
Rpt1707 S&EE
S&EE
SOIL & ENVIRONMENTAL ENGINEERS, INC.
16625 Redmond Way, Suite M 124, Redmond, Washington 98052, www.SoilEnvironmental.com (425) 868-5868
March 18, 2017
Ms. Cynthia Johnson
The Boeing Company
Cynthia.a.johnson4@boeing.com
CC: Mr. Michael Sullivan
Letter Report
Geotechnical Engineering Services
Proposed Gate D-50 Modification
Boeing Renton Plant
Dear Cynthia:
INTRODUCTION
Soil & Environmental Engineers, Inc. (S&EE) has been retained by you to perform a geotechnical evaluation
for the above-referenced project. The project will involve re-configuration of the traffic flow through the
existing D-50 gate. I understand that new underground electrical lines will be constructed, some minor re-
grading will be performed, and new asphalt pavement will be installed.
SURFACE AND SUBSURFACE CONDITIONS
The project site is located in the southeastern portion of Renton Municipal Airport. Figure 1, which is
included at the end of this report, shows the site location. The existing gate is surrounded by buildings, and
the site surface is covered with asphalt pavement. The gate is accessed by East Perimeter Road which
borders the west side of Cedar river and its levee. The site surface is relatively flat.
S&EE performed a previous soil test boring, B-2, at the location shown in Figure 1. Based on our
knowledge of soil conditions in the area, it is our opinion that the boring data are representative of the
subsurface conditions at D-50 gate.
The boring shows that the subsurface conditions at the site include fill over alluvial soils. The former is about
10 to 11 feet thick and consists of loose to medium dense silty sand, gravel and sand. The alluvial soils
include a soft to medium dense silt and sand layer to a depth of about 30 feet, then dense to very dense sand
and gravel below. This sand and gravel layer turns into a dense silty sand at a depth of 97.5 feet. Boring B-2
was terminated in this soil.