Aspect Consulting LLC 8/8/2016 - Laserfiche WebLink

Aspect CONSULTING July 14, 2016 Rich Hefti, P.E., Senior Engineer City of Everett Utilities 3200 Cedar Street Everett, Washington 98201 Re: Proposal for Geotechnical Engineering Services Three Lakes Pressure Sustaining Valve Improvements City of Everett UP No.3611 Three Lakes, Snohomish County,WA Aspect Project No. 160239 Dear Mr. Hefti: As requested,Aspect Consulting, LLC (Aspect)prepared this proposed scope of services for geotechnical engineering evaluations. The project involves design and construction of a bypass and a new pressure sustaining valve(PSV)along Water Transmission Line No. 5 at the Three Lakes Site near Machias. This will include new bypass piping and a new PSV that will be installed in parallel with an existing PSV at this site. The improvements will include one or more vaults, bypass piping,thrust blocks,and related appurtenances.The site is an unpaved and relatively flat,upland area. Geologic mapping indicates the Site to be underlain by continental glacial till. Proposed Scope of Work 1. We will plan and execute a site reconnaissance and subsurface investigation consisting of three to five excavator test pits in the Site area. Everett Utilities will provide us with a detailed site plan showing the extents of existing and proposed new PSV features. We will identify proposed test pit locations on the site plan and on the ground. We will then monitor and log three to five test pits. The City of Everett will provide an excavator and operator to perform the test pit excavation and backfilling. The City- provided excavator will have sufficient reach to dig 14-feet deep pits without any benching. The City will be responsible for locating all buried utilities before the subsurface investigations are done. In each test pit,the Aspect engineer/geologist will monitor and log the soils, and will obtain representative samples at selected intervals. Each test will be excavated to a minimum depth of 12 feet below ground surface. On completion,the test pits will be backfilled with excavated soils,tamped in place with the excavator bucket. There will be ground disturbance and some future subsidence at each test pit location. 2. Soil samples will be returned to our office for further examination and review. Selected samples may be submitted for geotechnical laboratory testing to determine index properties and assist in classification;tests will likely include natural moisture content, and grain size distribution. —�— Aspect Consulting.LLC 401 2nd Avenue S Suite 201 Seatt'r_ °'-4 - www.aspectconsulung corn