Geotechnical Investigations

A geotechnical investigation is the structured process of obtaining information on soil, rock and groundwater conditions at a site. The data supports safe and economical design of foundations, earthworks, retaining structures and slopes — and is a standard prerequisite before construction of residential, commercial, industrial or infrastructure projects.

Investigations typically combine a desktop review of geological mapping, historical data and nearby project reports with on-site field work such as borehole drilling, test pits, in-situ testing and laboratory analysis of soil and rock samples. The outcome is a geotechnical report that structural and civil engineers use to select foundation types, design footings and slabs, plan cut-and-fill, and manage groundwater and slope stability risks.

For mining and heavy industry, geotechnical input is equally critical: conveyor and equipment foundations, silos and bins, pipe racks, workshops, ROM pads and port structures all depend on reliable subsurface characterisation. Nunese integrates geotechnical recommendations with structural and civil design so investigation findings flow directly into certified drawings and specifications.

Soil testing and geotechnical investigation should be completed before you finalise structural design or commence significant earthworks. Regulatory and certification pathways in New South Wales and across Australia expect site-specific geotechnical data for new buildings, extensions and many civil works — not generic assumptions from adjacent lots.

You will typically need an investigation when:

Our scope is tailored to project stage, structure type and regulatory requirements. A typical programme may include the following elements, scaled to your site:

For buildings and structures subject to AS 2870, site classification quantifies the expected ground surface movement due to moisture changes in reactive soils. This directly influences footing system selection — from simple footings on Class A sites through to deepened or stiffened systems on highly reactive Class H or Class E sites.

Site classification is not a generic desktop label; it is based on investigation and testing of your lot. We coordinate testing and classify sites as:

Foundation recommendations translate investigation data into practical design input: footing type and depth, slab stiffness requirements, pier or pile needs, pavement subgrade preparation, and construction notes for excavations near existing assets. We work with structural engineers to align geotechnical parameters with analysis models and detail drawings.

Slope stability assessment supports cut slopes, embankments, retaining walls and dam-related civil works. Where groundwater is encountered, we identify implications for footing construction, seepage, and long-term performance — particularly important for industrial sites with bulk earthworks or below-grade structures.

On operating mine and port sites, investigations are planned around production constraints, access and safety. We specify investigation locations to match structural layouts and coordinate with drilling contractors so boreholes, pits and monitoring points are restored and documented in line with site requirements.

Nunese is a civil and structural consultancy. We do not operate drilling rigs on site; instead, we define the investigation scope, supervise coordination with accredited geotechnical drilling contractors, and interpret results for your project team. This model keeps a single engineering thread from investigation brief through to foundation details on structural drawings.

Our process: (1) agree investigation objectives with you and the structural scope; (2) prepare a brief aligned to Australian Standards and project stage; (3) coordinate field work and laboratory testing; (4) interpret results and issue foundation and earthworks recommendations; (5) support detailed design, certification and construction-phase queries. Prior investigations on nearby projects are used wherever appropriate to optimise scope and cost during early studies.