HomeMy WebLinkAboutPN_Project Narrative_Cedar River Bank Stabalization Borings_210611_v1.pdf
Memorandum
1101 Fawcett Avenue, Suite 200, Tacoma, Washington 98402, Telephone: 253.383.4940, Fax: 253.383.4923 www.geoengineers.com
To: City of Renton Parks
From: Brett Larabee, PE
Date: May 12, 2021
File: 00693-087-01
Subject: Geotechnical Exploration Plan – Cedar River Bank Stabilization Project
INTRODUCTION
This memorandum summarizes our exploration plan for completing geotechnical explorations for the Cedar
River Bank Stabilization Project in Renton, Washington. One boring is planned for the project. In order to
complete our boring a trail closure will be required. Additional details regarding our exploration plan are
provided in the sections below.
GEOTECHNICAL DRILLING
Schedule
The geotechnical drilling has not been scheduled at this time. Once the exact drilling date is determined, we
will provide this information to City of Renton Parks. We will provide at least two weeks notice of our drilling
date. Our work is expected to take one full day onsite.
Drilling Location, Trail Closure and Permits
The proposed drilling location and work area is shown on Figure 1. The trail will need to be closed to all
pedestrian access on the day of drilling. For safety reasons, a pedestrian bypass around our work zone cannot
be accommodated. Recommended locations for the trail closures are shown on Figure 1. We have assumed
that City of Renton Parks will provide public notification and signage for the trail closure. We will use traffic
cones and caution tape to establish the trail closure on the day of drilling.
GeoEngineers will coordinate obtaining a shoreline exemption permit in order to complete the boring. If other
permits are required to complete the drilling, we have assumed they will be provided by City of Renton Parks.
Site Access
We will access the site from the northwest via the Cedar River Dog Park and trailhead parking lot. The drilling
equipment will arrive on flat bed trucks. The City of Renton Parks storage area located adjacent to the dog park
will be used as our truck parking and laydown area. After offloading the equipment, it will be driven down the
trail to the work area. We have assumed City of Renton Parks will provide us access through gates in order to
access the laydown area.
Exploration Plan
The borings will be completed by a licensed driller (Holocene Drilling) under subcontract and supervision of
GeoEngineers. After mobilizing to the site, the drilling equipment will be unloaded and moved into the work
File No. 00693-087-01
Memorandum to City of Renton Parks
May 12, 2021
Page 2
area. An approximately 12-inch diameter core will be cut in the trail pavement at the drilling location. Temporary
erosion control measures will be set up around our work area. The boring will be advanced to 60 feet below
ground surface using a hollow stem auger. Soil samples will be collected at regular intervals using an SPT
sampler. A representative from our firm will continuously monitor the explorations, collect soil samples, and
keep a detailed log of the conditions encountered.
Cuttings generated during drilling will be collected and transported off site for disposal. After the completion of
drilling, the boring will be backfilled following Washington State Department of Ecology Guidelines.
We will restore the pavement surface at the ground surface using a cold mix asphalt patch. We will attempt to
limit disturbance to surrounding pavements, hardscaping and vegetation to the extent practical, however some
signs of disturbance should be expected after the completion of drilling.
CONTACT INFORMATION
Brett Larabee - GeoEngineers Geotechnical Field Coordinator – 208.722.2436, blarabee@geoengineers.com
Joe Callaghan – GeoEngineers Principal in Charge – 253.722.2796,
Holocene Drilling. – Drilling Subcontractor. Contact Jon Root – 253.848.6500
0693-087-01X Date Exported: 04/27/21Not to Scale
Figure 1
Site Plan
Geotechnical Exploration Plan
Cedar River Bank Stabilization Project
Equipment
Laydown Area
Site Access
Direction
Work Zone
Trail Closure
Approximate
Boring Location