Exploratory wells that are intended for the investigation of deposits or for pre-surveying tunnel and shaft construction projects are mainly created using core drilling technology. Geophysical and hydrogeological measurements can also be taken 'down the hole' in order to obtain more information. Our experts are able to use the extracted drill cores and measurement data to assess the quality of the deposits and the stability of the rock to be excavated for the future tunnel or shaft.

Our exploratory drillings produce drill cores of 101 mm diameter. This core size is ideal for carrying out an informative analysis of the samples, either directly on site or in the laboratory.

The brine leaching and extraction process requires the boreholes to be cased with several concentric pipes, each of which has a specific role to play. One of these functions involves pumping in and out the saturated brine solution and the fresh water needed for the leaching process. The brine is then delivered to the surface and the target material extracted from it. Our IDMG team has already completed numerous brine drilling projects for solution mining operations. We look forward to hearing from you.

Freeze holes are usually drilled in a circle and can be vertical, horizontal or even deviated. A pipe is installed into each hole and coolant is then circulated through the pipe so that the water-bearing ground is transformed into an enclosed freeze zone. This ice wall seals up and stabilises the water-bearing beds and creates a protection zone for the excavation of shafts, tunnels and other types of underground cavity.

We use directional drilling technology for our freeze holes and can drill at very high levels of accuracy to depths of over 800 m. Our team has already drilled over 200 km of freeze holes under the most difficult geo-hydrological and climatic conditions and has set up all the equipment needed to establish a stable and effective freeze wall.

Under favourable geological conditions it is possible to drill wells for the extraction of warm deep-level groundwater. This thermal water can be pumped to the surface and its thermal energy drawn off for heating and electricity generation purposes. After cooling the water is usually delivered back into the aquifer via another borehole.

If you have selected a suitable site for such an operation we have the capacity to drill boreholes that will ensure the success of your geothermal project.

If the data from exploratory drilling work carried out ahead of a shaft or tunnel construction project indicate the presence of unstable and/or strongly water-bearing strata the solution is often to drill a series of freeze holes in order to create a freeze zone that will provide the required stabilising and sealing effect. The refrigerating capacity needed to create the freeze wall is generated by a system of compact refrigeration units that are specially designed for the job in question.

Our highly qualified personnel use advanced and environment-friendly cooling technology to chill the coolant medium (down to minus 40°C). This equipment is able to develop the freeze wall and to maintain it throughout the construction phase. We employ the latest measurement and process control techniques to monitor the freeze process, with continuously optimised fibre-optic technology being deployed to measure the strata temperatures in order to maintain control of the freeze zone. Fibre optics provide a highly accurate analysis tool and deliver exact data for thermal modelling.

Our portfolio now includes the planning and implementation of a number of highly challenging and exceptional freeze projects.

When the shaft or tunnel has been successfully excavated using the freeze method, and the support or lining system installed, a frozen mass will remain in the ground even after the refrigerating plant has been switched off. This freeze zone will always be slow to thaw out under natural conditions. However, some of the subsequent time-critical project operations can only be undertaken under non-frozen strata conditions. In order to enable this ancillary work to be carried out as promptly as possible the thawing process in the freeze zone can be accelerated by circulating warmed brine through the freeze pipes.

By successfully planning and executing this artificial thaw our team is able to help clients move on quickly to the next stage of the construction process and in this way save valuable build time.

The directional drilling technique allows the direction of a borehole to be controlled in such a way that the path of the hole can be changed in any desired direction. As well as allowing the borehole alignment to be varied at will this technology also makes it possible to drill boreholes of almost exact verticality.

We employ this technique using our own drilling and measuring systems along with our own highly-trained personnel, which is particularly important when drilling freeze holes.

Statutory regulations usually require boreholes and wells to be permanently filled-in when they reach the end of their useful life. This calls for specialised equipment and technology designed to carry out various operations in the existing boreholes and wells, such as cutting, milling, perforating and cementing. This operation creates a permanent seal of the highest quality.

We have the equipment and highly-trained staff needed to undertake extremely demanding projects of this kind and have developed the capacity for plugging and abandonment of boreholes and wells of 1,500 m in depth.

Clients have approached us for help in carrying out ground treatment and consolidation work with hydrological sealing in various underground environments such as mine shafts and roadways, subsurface caverns and tunnel structures. As well as creating a hydrological barrier against the surrounding strata these projects have also had the additional objective of increasing the stability and integrity of the rock body. These strata injection processes are carried out using pipe shield equipment with material injection, all backed by an appropriate performance monitoring regime.

Our highly-skilled team of experienced professionals can provide the support you need for planning and executing specialist work of this type.

Solid, clear-sighted planning is essential for the execution of technically challenging and tightly scheduled projects and this phase of the operation essentially holds the key to overall success.

To help you realise your project we will accompany you through each of the critical planning phases, from concept design and approval through to the implementation planning stage itself. This means working in full compliance with local regulations so that we can find a technical and commercial solution that best meets the needs of your project.

Numerical modelling has now become the state of the art in many areas for selecting the most appropriate methods and making the most effective use of the available materials and equipment. This kind of modelling provides a solid basis for key decision-making and enables a high degree of optimisation when it comes to conserving resources and saving time both in the planning phase and during the further course of the project. It is especially useful for the thermal modelling of ground freeze and thaw projects as it enables us to predetermine the technical and economic optimum for the construction work and to develop projections for the progression of the freeze wall. We also use temperature measurement data to model the actual state of the freeze zone as the project advances and in this way can create the foundation for ongoing project optimisation measures.

IDMG specialists have the broad-based experience needed to help you manage and coordinate specialised modelling tasks for complex ground freeze and thaw projects, large or small.