We carry out site investigations for all sizes of projects, residential and commercial, from small jobs that require hand auger equipment, to large-scale commercial and land development projects that may require supervision of deeper, machine-drilled boreholes and Core Penetration Tests (CPTs). We can organise specific field and laboratory testing of subsoils and rock, to obtain a detailed understanding of the variability of the ground beneath a site, including any possible contamination issues. This can be further expanded on by engaging contractors for geophysical (using ground vibration, ground radar, magnetic or induced potential) investigations if necessary.

After a large seismic event, there is often a need to provide immediate and then longer-term geotechnical remediation recommendations. EDC’s Geotechnical analysis and reports provide design recommendations for immediate repair and ongoing ground stabilisation. EDC’s ‘earthquake engineers’ have first-hand experience in shallow and deep assessment methods, allowing us to assess geotechnical risks including liquefaction, slope stability and ground settlement.

Using our expertise in computer software to analyse the risk of future instability and our geological interpretation skills, we provide technically-sound and comprehensive advice for new developments on sloping land and remedial work on land affected by past, present or possible future instability.

EDC provides specific geotechnical designs to suit specific structure and ground interaction requirements including shallow and deep foundations, mass, segmental and cantilevered retaining walls. Our geotechnical experts integrate with our structural engineering section to provide the detailed calculations, producer statements, design drawings and specifications.

We oversee earthworks projects, providing construction observation and field testing to examine and approve the progress in relation to the consent requirements. We certify the completed works and provide Producer Statements and Geotechnical Completion Reports, confirming the ground is appropriate for foundation designs. We also monitor retaining-wall construction, drainage, stormwater, sanitary and on-site wastewater disposal.

We provide geotechnical reports detailing site investigation and analysis findings, and provide comprehensive recommendations for earthworks, slope stability measures, retaining walls and foundations; essential for detailed structural design and the Building and Resource Consent application processes.

Our geotechnical team work closely with our environmental engineers to carry out exploratory holes to identify soil types and suitability. This information is then compiled into a report to advise on solutions for on-site wastewater treatment and disposal systems for rural developments.