Project Highlights

Solomon Mine, Pilbara WA

The Brad Tailings Storage Facility (TSF) is located at the Solomon Mine site in the Hamersley Ranges, approximately 60km north of Tom Price and 215km south-west of Port Hedland in the Pilbara region of Western Australia.

STATS was engaged by Fortescue to carry out geotechnical drilling works at the TSF embankment wall, installing vibrating wire piezometers and standpipes to monitor the structure’s performance. This was followed by earthwork trenching to lay, install and joint instrumentation cabling from the borehole locations through to the nominated dataloggers at the monitoring hut.

The Kalgoorlie Nickel Smelter Renewal (KSR) project was in the Selection Phase Study (SPS), with basic engineering for all disciplines in progress at the time. A significant proportion of the project involved modifying and interfacing with existing structures.

STATS was engaged by BHP to provide engineering assessments to determine whether the existing structures had adequate capacity, including accounting for current condition and future service life, and to carry out site inspections of interfacing points to mitigate cost and schedule risks during the construction phase.

Often, the available records (e.g., drawings, reports, and calculations) were insufficient for the above items to be completed. This investigation work required specialised site activities to obtain further information on the existing assets. Investigation work, sampling and non-destructive testing were carried out for the following:

• KNS Furnace Structure
• Strong Acid Storage Remediation – Pump Bund Structure
• Settling Tank of Granulation Pit, KNS
• KNS SF Electrostatic Precipitator Structure
• Acid Plant Structure, KNS
• Effluent Plant Structure, KNS

STATS was engaged by Yindjibarndi Energy Corporation to carry out a geotechnical feasibility investigation for a proposed 75 MW solar farm (Stage 1), with provision for expansion to 150 MW in total (Stage 2). The proposed development area is near Weymal, south of Karratha.

Stage 1 involves the installation of solar panels on piled foundations across two separate areas. The site is in close proximity to the existing Rio Tinto Millstream 220 kV substation, which will serve as the connection point for the solar plant to the network. Rio Tinto will be responsible for upgrade works at the existing Millstream substation, including a new 33 kV switch room for the solar farm.

The Mt Marion Lithium Project located South Westerly of Kalgorlie is a Greenfields site that has significant amount of spodumene deposits.

Scope

• Geotechnical Investigation and Sampling including the use of Geotech Drilling Rig and Excavators for Bulk Sampling for the Mines mining, crushing and processing plants, storage and handling facilities, camps, offices and associated infrastructures.
• Preliminary baseline environmental sampling and testing work for an Emulsion Base Compound.
• Detail earthwork specifications and detailing for the construction of a Product Stockpile Floor that was positioned over a valley of clayey and highly plastic soils with very low permeability properties. STATS designed and incorporated the use of subsurface drainage channels to ensure perched water flow is mitigated and controlled.
• Supervised and carry out Materials Testing regime and Compaction Testing regime for the construction of the Founding Pads for the various structures and Crane Pad.

Outcome

Under a tight budget and very limited timeline, STATS completed the entire Geotech Investigation timely and assisted the Earthwork Contractors throughout the entire process until completion, including certification of material test results and compaction tests. Areas of non-conformance identified were reported promptly and remediation measures rectified within a quick turn-around.

The project demonstrated that a detail understanding of the materials properties, good planning and a close working-relationship between earthwork contractors and STATS laboratory and based on a Call Out ex Perth arrangement can be a successful outcome, versus a typical arrangement based on a site laboratory setup.

Woodside Energy Ltd established a Karratha Gas Plant (KGP) Life Extension (KLE) Program with the intent of sustaining the technical integrity and reliability of the existing infrastructures. STATS worked under Applus RTD and BGC Contracting to carry out detail concrete inspection, sampling and concrete non-destructive tests to determine the concrete strength and durability of various Bridges, Buildings, Drains and Culvert Structures.

Scope

• Concrete inspection, defects mapping and reporting.
• Concrete non-destructive tests comprising of Ground Penetrating Radar, Cover Meter, Ultrasonic Pulse Velocity measurements, Rebound Hammer Tests, Corrosion Mapping, Half Cell Potential, Concrete Resistivity tests were conducted.
• Laboratory tests comprising of Unified Compression Strength, Chloride, Sulphate, Cement Content analysis, Carbonation Tests and Concrete Petrography Examination were conducted.
• Analyse results and provide recommendations to the structures concrete strength and durability.

Outcome

Under a highly restricted, challenging and very difficult work environment, STATS completed the Inspection, Material Sampling, Non-Destructive Tests and reporting satisfactory for the Client.

Limestone-Marble Bar Road is a single lane carriageway which extends approximately 7.6km from the Marble Bar Road Intersection to Corunna Downs Road Turn off. The objectives of the investigation were to determine the existing pavement structural capability of Limestone-Marble Bar Road, as well as the structural capacity of some existing culvert structures underneath the pavement, and to review if they can support further increase in vehicular loading from Quad Trains that will be transporting iron ores from a nearby Mine.

Scope

• Falling Weight Deflectometer survey was first conducted on the existing haul road, identifying areas of weakness showing high deflections.
• Pavement test pitting, site classification, DCP tests to determine the type of soil classification and material properties.
• Evaluate the load carrying capacity and serviceable life of pavement structures.
• Structural check on the load carrying capacity and durability of the existing culvert structures.
• Provide recommendations on repair and rehabilitation.

Outcome

STATS completed the entire Pavement Investigation, Geotech Investigation, Laboratory Tests and Material Tests that assisted the Client with an outcome that allowed them to make conclusive decision on the use of the existing Haul Road and subsurface culvert structures, and spending capital limited to areas of concern instead of the entire section.

The Local Government requested STATS to carry out a Geotechnical Assessment of the Limestone Cliff Wall condition located along East Street Fremantle. STATS is given to understand there were occasional fallen cobbles and stones that pose a hazard risk to pedestrians underneath and vehicles travelling along the road. STATS conducted an inspection and a Geotechnical risk assessment on the overall stability of the wall, identified areas of concern and provide a rehabilitation solution for the limestone wall.

Scope

• Detail visual inspection on the condition of the limestone wall and highlight areas of high Geotechnical Risk.
• Provide cost and feasibility options of rehabilitation for the Local Government.
• The rehabilitation technique incorporating Shotcrete was selected.
• STATS provided a design of the Shotcrete mix including that of colour selection to blend with that of the existing limestone colour.
• Supervised the removal of high geotechnical risk areas incorporating the use of machineries and breakers.
• Supervised the application of shotcrete to identified areas, followed by final inspection.

Outcome

STATS completed the entire Geotechnical Inspection, Supervision and Rehabilitation program for the Local Government successfully.

The BHPBIO Berth A & B wharf structure was constructed in 1960s and it consists of a 650m long by 25m wide reinforced concrete deck with integrated concrete shiploader runway track beams supported by transverse concrete headstocks and steel piles.

Scope

• Detail visual inspection, defects and cracks mapping including measurements.
• Conduct cores and concrete samples extraction for further concrete strength and concrete durability assessment.
• Conduct concrete non-destructive tests utilising Ground Penetrating Radar, Rebound Hammer, Carbonation Tests and Corrosion Mapping.
• STATS provided a design of the Shotcrete mix including that of colour selection to blend with that of the existing limestone colour.
• Laboratory tests comprising of Unified Compression Strength, Chloride, Sulphate, Cement Content analysis, Carbonation Tests and Concrete Petrography Examination were conducted.
• Analyse results and provide recommendations to the structures concrete strength and durability.

Outcome

The Field Inspection and Testing Program was completed after a nine months intense work program to address platform access, existing shipping schedules and tidal impacts. Under a highly restricted, challenging and very difficult work environment, STATS completed the Inspection, Material Sampling, Non-Destructive Tests and reporting satisfactory for the Client.

STATS was engaged by our Client, Coffey Geotechnics, to conduct a pavement investigation and sampling program, to determine the material properties of the newly constructed hardstand of the Port, which presented signs of distress and defects. Due to a busy day time operational activity, the pavement investigation and sampling work can only be conducted past midnight, and all areas of investigation are to be reinstated satisfactory prior to the next day time operation.

Scope

• Conduct pavement test pitting, logging and sampling work.
• Conduct laboratory tests on the Asphalt Layer, pavement basecourse and subbase, and underlying subgrade layers.
• Provide factual report of findings and observations to our Client.

Outcome

The Field Investigation and Testing Program, including that of reinstatement was completed satisfactory and within a very tight timeline for the Client.