Percussive Drilling
Percussive Drilling is a cost effective, simple and largely spoil free method of conducting shallow Geo-Environmental site investigations in unconsolidated ground. It is particularly suited to limited access contaminated sites where flushing and spoil disposal might prove contentious.
GEOTOOL GTR-790
Ecologia employ a Geotool GTR-790 for a large percentage of our shallow Geotechical testing services, but we also recognise its value as an intrusive tool for general site investigation where various economic and practical factors might rule out the use of a larger system, but where window sampling is unviable.
Capable of achieving depths of up to 14m with continuous sampling, the Geotool percussive drilling rig is a versatile and pragmatic site investigation tool.
Designed primarily as a Dynamic Testing tool for geotechnical work, the specifications of the machine are built around the standards for SPT (Standard Penetration Test) and DPSH (Dynamic Probing Super Heavy) testing. In simple terms, the machine is based on the principle of a drop weight of known mass (63.5kg) falling through a known distance (750mm) to impact on the tool string, driving it into the ground.
The energy imparted by the hammer may be used for the purposes of driving geotechnical testing tools or for purposes of driving a sampler into the ground.
Ecologia find that one of the most valuable aspects of percussively driven samplers is the possibility of driving a casing into the ground simultaneously with the advance of the sampler. This enables a single drilling operation to effectively case off and support difficult ground, whilst still obtaining a high quality linered sample. After achievement of depth, the casing remains in the ground and can be used as an installation guide prior to its extraction, allowing for a high-quality well installation without the risk of bridging or collapse.
The rig is equipped with a 15 tonne vertical lift hydraulic tub clamp for easy extraction of tools.
For versatility, Ecologia have invested in the following toolsets for the Geotool system:
- SPT testing cones, split spoon and rods
- DPSH cones and rods
- Window Sampler Barrels in 3”, 2” and 1” Outer Diameter
- RAMBO™ System Simultaneous Case/Sample system in 3” and 4” OD. Running with removeable plastic liners for ease of sample recovery and core confinement prior to testing/sampling.
These tools allow us to perform a full geo-environmental SI with a single lightweight tracked rig that can be mobilised to site in the back of a conventional long wheel base van.
Window Sampling
We recognise that many environmental site investigations require shallow sampling from multiple locations, often in areas with limited access. Ecologia also operates hand held window sampling equipment.
This allow us to provide cost effective site investigation and installation capability where a rig is inappropriate. Ecologia operates a range of tooling for hand held systems, allowing us to drill boreholes up to 76.2 mm (3”) OD. Should the ground be prone to collapse, we can offer a 63.5 mm OD cased system with sampling or equivalent open hole using lost cone.
