2015/07/15 Council Agenda Packet

1,31 -F 4 �n C r VSO RK - City of Everett June 26, 2015 Project No. 150135-2 We will subcontract a local geotechnical driller to drill pavement cores and exploratory borings at three locations along Lower Norton Avenue (providing soil and groundwater data at an average spacing of 600 feet along the new gravity sewer). Our field engineer will record the pavement section layer thicknesses to the nearest 1/2 -inch. We will then advance hollow stem auger borings and obtain disturbed soil samples in accordance with the Standard Penetration Test (SPT) method at 21/2 -foot intervals. Each boring will be drilled/sampled to 14 feet below pavement elevation. One of the three borings will be completed with a slotted standpipe piezometer so that groundwater levels can be monitored during the course of the design. The other two borings will be backfilled with bentonite and the ground surface will be patched with quick -setting ready -mix concrete. We will complete all of this work in a single day. 4. Soil samples will be returned to our office for further examination and we will provide the City with a brief summary of conditions encountered in the cores/borings. Selected samples will be submitted for geotechnical laboratory testing to determine index and engineering properties. Tests may include moisture content, grain size distribution, and moisture - density. 5. We will then conduct geotechnical engineering analyses with respect to trench earthwork including temporary excavations, construction dewatering, and potential suitability for reuse of on-site soil as trench backfill. 6. We will prepare and submit a draft geotechnical report with design and construction recommendations for trench excavations, temporary shoring, construction dewatering, pipe support, pipe zone bedding and general trench structural backfill materials and compaction, pavement restoration, and temporary erosion control. We will address any review comments or.questions on the draft and issue a Final Geotechnical report, sealed by the undersigned licensed professional engineer. Budget We are prepared to undertake this project on a cost, plus time and materials, basis for a budget not to exceed $11,855. As requested, this budget includes a $2,000 contingency to cover unanticipated expenses and minor scope changes. A detailed breakdown of our costs is presented in the attached spreadsheet. A copy of our WSDOT-approved overhead rate determination (199.21%) is also attached. Schedule Assuming NTP on July 27, 2015, our final geotechnical report can be submitted on or before September 18, 2015. Our proposed schedule with key milestones and assumptions is detailed below: Week 1 (week ending (W/E) July 31): Site Reconnaissance and meet with City representatives. Assumes the City arzd their survey corrsultarzt are available to meet that meek. Week 2 (W/E August 7): Aspect's Work Plan and Traffic Control Plan submitted to the City for revie«.7/approval. Paje 2 65 P