Geotechnical Assessments, completed by a “suitably qualified and experienced geotechnical practitioner” who has appropriate professional indemnity insurance (Geotechnical Engineer or Engineering Geologist) are required by councils, engineers, builders and designers when site stability and erosion are paramount.

All Geotechnical Assessments are completed in accordance with Australian Standard 1726-1993: Geotechnical Site Investigations. Residential Foundation Classifications are completed in accordance with Australian Standard AS2870-2011: Residential slabs and footings, and are usually complemented by a Wind Load Rating: AS4055-2006: Wind loads for housing.

All Geotechnical Assessments (and “Soil Tests”) require a risk assessment of geotechnical hazards. Hazards may include landslips, expansive / reactive clay soils, steep land, areas subject to inundation, areas containing fill material, low Bearing Capacity sites, coastal erosion, contaminated sites, groundwater, erosion, or dispersive soils.

Site investigations include mapping of geomorphological features and hazards, profile mapping (utilizing hand or mechanical augers, or test pitting with an excavator, and soil sampling. Laboratory assessment of clay soils is often required to accurately classify the site (Shrink / Swell Assessment).

Residences located on sites that do not have council provided wastewater services require Onsite Wastewater Assessment and Wastewater System Design. These assessments and designs must be completed in accordance with Australian Standard AS/NZS1547:2012: On-site domestic-wastewater management, and must be completed by accredited Wastewater Designers.

A wastewater Site and Soil Evaluation Report assesses a site for suitability to dispose of domestic onsite wastewater and will ultimately be used to determine the type, size and position of a suitable wastewater system.

Onsite Wastewater can be treated and disposed of utilizing many different types of systems. These include “traditional” septic tank and trench based systems, On ground sand filter systems (Bottomless Sand Filters, Wisconsin Mounds and Raised Beds), Aerated Wastewater Treatment Systems, and Composting toilets and greywater disposal systems to name a few.