Geotechnical Investigation for Somerton Bridge

Overview Tamworth Regional Council is seeking a suitably qualified contractor to undertake a geotechnical investigation for the Peel River, Lower Somerton Road Bridge (Somerton Bridge). Scope The scope includes: Preparation of a Health, Safety and Environmental Plan, with acceptance of the plan by Council prior to commencement of fieldwork Site establishment in accordance with the Health, Safety and Environmental Plan, including any access improvements required to undertake the works Development, approval and implementation of traffic control measures, including detours, in accordance with the TfNSW Traffic Control at Work Sites June 2026 where applicable, with Council reviewing the approved Traffic Guidance Schemes (TGS) Undertaking of field work, including implementation of environmental controls as detailed in the Environmental Plan, conducting geotechnical investigations and restoring disturbed areas to their original state at the conclusion of testing (indicative testing locations and schedule are detailed in Section 4) Collection of soil samples for chemical testing, including testing for chloride ion content, sulfate content and pH levels (chemical test schedule detailed in Section 4) Provision of a water cart and water, if required, as a water source for borehole drilling Disposal of any drilling waste, slurry or excess spoil to a licensed waste disposal facility Test pit pavement sampling and testing in accordance with AS1289 and TfNSW Testing Methods, including TS02794.01 (formerly T100) sampling of road construction materials, particle size distribution, liquid limit and plastic limit (Atterberg limits), maximum dry density, California Bearing Ratio (CBR) 4-day soaked, and Dynamic Cone Penetrometer (DCP) testing (3 per test pit location, in-situ CBR) Sampling and laboratory testing Analysis and reporting of results in line with AS1726 Preparation of a Geotechnical Interpretive Report, including easting, northing and reduced surface level (to AHD) for each borehole; factual testing results with rock classifications in accordance with AS1726; an interpreted geotechnical model, including a long section of the assessed subsurface lithology, to determine appropriate founding levels; recommendations on design parameters for piled foundations for the geological strata (including unconfined compressive strength, ultimate bearing capacity, shaft friction, lateral bearing capacity, Young's Modulus, modulus of subgrade reaction for use as linear elastic springs in the bridge design model, and material properties such as unit weight, friction angle and cohesion), together with a description or reference of the methodology or literature used to determine the rock design parameters; soil and rock permeability rates; and chemical test results for chloride, sulfate and pH levels Enquiries Contact: Angie Taylor, Operations Engineer Phone: 0267675506 Mobile: 0427846682 Email: a.taylor@tamworth.nsw.gov.au