Deep Artesian Bore Drilling

Project Management, Licensing, Drilling, Pressure-cementing and Construction

The Impax Group have been operating an Atlas Copco Range III drill rig in western NSW for the majority of 2016-2020, using it to drill flowing artesian bores to depths of over 1000m. All aspects of the drilling program have been managed by The Impax Group, with a major component being arranging for licensing and approval for the bores involving correspondence with Water NSW. These bores have all been pressure cemented in order to ensure aquifer integrity, eliminate potential contamination and corrosion risks and in accordance with licensing requirements.

The bores are drilled using the rotary mud drilling method with two separate strings of steel casing pressure cemented in place to ensure hole stability and aquifer integrity.

The Impax Group are responsible for preparation of Site Specific Safety and Environmental Management Plans, collection of representative formation samples, bore development and testing, and bore reporting and submission of all necessary data to the Principal.

Town Water Supply Hydrogeological Investigations

Project Management, Desktop Assessments, Drilling and Pump-testing

The Impax Group have worked on a variety of town water supply drilling projects over the last 8 years for western NSW towns including:

Dubbo, Wellington, Narromine, Trangie, Warren, Nevertire, Nyngan, Collie, Tooraweenah, Bourke, Walgett, Collarenenbri, Cumborah, Coonamble, Gulargambone and Gilgandra Shire Councils.

These projects were generally funded under the NSW Government Water Security for Regions program. As such, a number of Councils were awarded funding for the drilling and installation of bores, but had no real understanding of where to locate the bores, or how to best incorporate new bores into their existing town water supply network. The Impax Group engaged the services of Environmental Strategies to provide specialist hydrogeological services including desktop assessments, pump testing and reporting to our clients in Western NSW. The Impax Group conducted all of the required field work including test bore drilling, production bore drilling, developing and pump testing and reporting. 

NSW Government – NSW Coal Basins Monitoring Bore Project

Project Management, Drilling, Development and Sub-Contractor (geophysical logger) Management

The Impax Group were awarded a total of 5 separate contracts to drill and construct 30 groundwater monitoring bores as part of the NSW Governments Water Monitoring Strategy for Coal Basins. The total value of the contracts was approximately $10 million dollars.

The 30 groundwater monitoring bores were constructed across the Gunnedah, Gloucester, Hunter and Sydney coal seam fields.

The location of the bores were all adjacent to WaterNSW Sydney Water Supply Dams, within National Parks or within State Forest areas and had resulted in strict environmental management conditions applying to the project. In particular, all drilling fluid must be captured and stored in above ground tanks for off-site disposal.

All monitoring bores were been drilled using the rotary mud drilling method, with specific aquifers targeted based on a review of chip samples and hydrogeological assessment of down hole geophysical logging date. Bores were constructed using threaded steel casing and zonally isolated using pressure cementing. Downhole geophysical logging information was then used to determine a suitable interval for explosive perforation across the target aquifer.

The Impax Group were also responsible for developing the monitoring bores and conducting water quality monitoring for a twelve month period at the completion of each bore.

Alkane Resources Hydrogeological Assessment

Project Management, Drilling, Pump Testing and Reporting

The Impax Group were engaged as Principal Contractors by Alkane Resources to explore the potential of the Upper Macquarie alluvium groundwater resource, and its suitability to provide production water for their nearby Toongi mining operation.  The project involved a desktop hydrogeological assessment, a surface electro-magnetic TEM survey and test bore drilling for aquifer evaluation purposes. The Impax Group then completed multiple pump-tests and evaluated the data in order to provide recommendations for production bore drilling, which was subsequently drilled by a cable-tool drilling company under the supervision of The Impax Group.

Iluka Resources Eucla Basin South Australia

Monitoring Bore Drilling and Vibrating-wire Piezometer Installation

The Impax Group were contracted to work on a pre-feasibility study which involved monitoring bore drilling, geophysical logging and vibrating-wire piezometer installation. Data collected throughout this project was ultimately evaluated by Iluka Resources as part of their ongoing exploration and resource development program.

Shenuah Watermark Coal Exploration

Drilling, Core Collection, Decommissioning and Borehole Sealing

The Impax Group were engaged on a long term multiple rig coal exploration drilling program near Gunnedah NSW. Up to 3 rigs were in operation at the site at any one time, drilling to depths of 400m to 600m using HQ diamond core drilling. Core samples were collected and logged under the supervision of a geologist, and at the completion of drilling bores were sealed from bottom to top using cement grout placed via trammie pipe. 

Iluka Resources Hydrogeological Investigation Balranald

Drilling, Geophysical Logging, Pump Testing and Well Injection

The project involved the drilling of a number of monitoring bores, production bores and injection bores as part of a feasibility study into dewatering the target aquifer for mining extraction purposes. The Impax Group also conducted 7-day continuous pumping/injection tests, where water was pumped from production bores through surface pipelines to injection bores up to 1,500m away. The water was then pumped down the inject bores and back into the aquifer, whilst adjacent monitoring bores were used to measure water levels in aquifers and the data ultimately interpreted to determine aquifer properties.

WA Government Department of Water

Monitoring Bore Drilling and Pressure Cementing

The Impax Group were awarded a contract by the Western Australian Government – Department of Water to drill and install 26 groundwater monitoring bores near Geraldton WA. The bores ranged in depth from 105m to over 350m and were drilled through challenging sand/gravel formations using the rotary mud drilling method. Due to both the depth of most of the bores and the highly saline upper aquifers the contract required the pressure cementing of the upper bore casing, typically to a depth of 150m to 200m. Pressure cementing was conducted by The Impax Group under the supervision of Department of Water Hydrogeologists, and involved the calculation of the correct amount of cement grout, grout mixing, conditioning and testing and the pumping of the grout down the bore holes under pressure using two cement plugs to separate the grout from the drilling fluid and follow on mud.

Victorian Government Goulburn-Murray Water

Monitoring Bore Drilling

The Impax Group were awarded the tender to drill and construct over 150 groundwater monitoring bores on behalf of the Victorian Government as part of their State Observation Bore Network within the Goulburn-Murray River Valleys.  Bores were drilled and constructed over a 1 year period in both single and multiple aquifers, according to detailed contractual requirements under the supervision of hydrogeologists from Goulburn-Murray Water. In particular, great care had to be taken in placing both the gravel pack filter envelope and bentonite seals, and appropriately cementing the annular space behind the bore casing in order to preserve aquifer integrity and ensure the bore is fit for purpose. Safety and environmental management was also a major challenge throughout the project as the majority of bore sites were located on crown lands within road reserves, and thus the project required great attention to compliance requirements, management plans and mitigation measures.

Tomingley Gold Project Groundwater Assessment

Hydrogeological Impact Assessment and Reporting

The Impax Group were contracted to prepare a groundwater assessment for the proposed Tomingley Gold Open Cut project. The final report completed by The Impax Group included the identification and description of the groundwater resources at the site and what potential impact the proposed works may have on such resources. The report also outlined recommended mitigation measures and management plans that would need to be implemented to reduce impacts and protect the groundwater resource throughout mining activities.