2006/01/11 Council Agenda Packet

DEC.20-2005 TUE 03:26 PM HWA GEOSCIENCES FAX NO. 4257742714 P. 03 December 20,2005 J HWA Proposal No.P 5525 The northwest area extends approximately 1,400 feet for three blocks along the alley between Rucker Avenue and Hoyt Avenue, from 23rd Street to 2011'Street. Plans indicate the sewer is 10-inch concrete pipe,and it is greater than 9 feet deep. It is our understanding that a similar sewer replacement project was recently constructed using open trench construction techniques. You presently envision these sewers will be replaced using open cut methods,however,some areas may be upgraded using pipe-bursting methods. PROPOSED SCOPE OF WORK We propose to conduct a geotechnical study consisting of the tasks described in the following paragraphs. As requested,the southeast area is excluded from our scope of work. Task' I. Site Reconnaissance and Review of Exis-ting Information: We will review existing/available geotechnical and geologic data for the project site area to gain an overview of soil conditions that may be expected for this project. This includes a geotechnical report provided by you,prepared by Landau Associates, for"North End Flood Reduction Ic". Tusk 2. Coordinate Field Explorations and Obtain Utility Clearances: We will coordinate a field exploration program aimed at providing geotechnical data along the proposed sewers. We will design our field exploration program to supplement existing geotechnical data that may exist along these sections of sewer. We will coordinate our work efforts with the City of Everett. We will notify the 1-CALL underground utility location service and request utility locates at the proposed exploration locations. Everett Public Works will clearly mark all City-operated utilities before we begin the explorations. Task 3. Conduct Subsurface Explorations: We will conduct a subsurface investigation program consisting of a minimum of six exploratory borings and two backhoe test pits. The borings will be drilled by a driller under subcontract to HWA, and the test pits will be dug by Everett Public Works personnel using a City-owned backhoe. The explorations will be located in the following general areas: a) Northeast arca: One boring in the parking lot south of the park,near SMH Z7, and two test pits along the east/west section of the sewer; one near SMI{Z 6 and the other near SMH Z 11. b) Southwest area: One boring in the alley just north of the intersection with Everett Avenue. c) Northwest area: One boring at the intersection with 20th Street and one boring in the alley behind the residence at 2201 Rucker Avenue. A partial lane closure will be required at 20th Street. The borings will be drilled using a truck-mounted drill rig advancing hollow-stem'augers. Each of the borings will be advanced approximately 5 feet below proposed sewer invert elevation. P5525 v3.dnc 2 HWA GEOSCrENCES INC. 24