Alton Drilling has expertise in four main areas of drilling. Our main focus is Exploration Drilling, but we also have skills and experience in Environmental, Geotechnical, and Aircore drilling.
One Stop Shop
We offer a comprehensive drilling contracting service with the ability to provide experienced staff, purpose built rigs, custom built camp and rig huts, helicopter support, and management of health, safety and environmental risks.
We are able to keep downtime to a minimum with regular maintenance programmes, a wide range of spares in stock, and thorough knowledge of our equipment.
Since Alton Drilling was established in 1983 we have been involved in a wide range of Drilling projects. With a focus on exploration drilling we have built up expertise and an experienced team to enable us to provide a full service offering.
Alton Drilling has been involved in coal and gold Exploration Drilling for over 26 years. This is our foremost area of expertise and we have several specialist rigs available for this type of drilling. We have worked extensively on the coal fields of the West Coast of the South Island, New Zealand, as well as various large gold exploration projects around the country, and mineral exploration worldwide. Our diamond drilling rigs are capable of drilling to depths of over 900 metres and produce PQ, HQ and NQ size holes.
We have undertaken a large number of Environmental Drilling projects throughout New Zealand including the drilling of many groundwater production wells, piezometer monitoring wells, installation of inclinometers, permeability testing and groundwater contamination sampling.
Alton Drilling was the first drilling company in New Zealand to introduce Air Core Drilling to the industry. This was bought about by an extensive ilmanite drilling programme based on the west coast of the South Island, drilling in the excess of 25,000 metres. With the success of this method, air core was then introduced into coal quality drilling on the coast, where it is still being used today. We have also used this method successfully in drilling for alluvial gold deposits in Southland and river sands in Waikato. We believe this method has undeveloped potential in the New Zealand drilling industry.
Alton Drilling has completed numerous Geotechnical Investigation Drilling programmes, including working on some of the country’s largest and oldest dams including, Arapuni, Karapiro and Manapouri. Much of this work involved working in either confined spaces or inaccessible remote locations. Another major project was based at an Auckland wastewater treatment plant. Over a four year period, Alton Drilling completed major concrete cutting and drilling along with site investigation and temporary and permanent dewatering of the complex.
Different forms of drilling:
Mineral exploration projects usually involve a search for certain minerals or materials that are valuable assets on the world market. Exploration in drilling is described as a search for unknown or hidden minerals whereas investigation is the process or checking to establish if the mineral still exists in commercial quantity.
Diamond wireline drilling is the essential method for most efficient core sampling. This method allows for drilling in some of the hardest ground in New Zealand. Wireline drilling enables the core barrel, with its sample, to be pulled up by a wire inside the drill pipe without having to hoist and dismantle the whole assembly.
Wireline Drilling provides samples at hand in a small fraction of the time it would take with conventional drilling and a continuous, virtually uncontaminated sample of geological formation, even when drilling through caving or eroding formations.
Environmental drilling involves combining the two specialised areas of geotechnical and waterwell drilling methods to monitor the quality of groundwater and assist in the control and remediation of groundwater contamination. Environmental drilling and sampling methods are carried out in a number of areas such as:
- Government and local regional councils required site testing and monitoring for sites such as landfills or waterways that have a potential for pollution.
- Monitoring and testing of environmentally sensitive areas such as protected lands or public water supply regions.
- Testing to determine the source and extent of a known contamination problem.
- Sampling and well construction for recovery or remediation of pollutants in groundwater.
- Identification of a product (oil, petrol etc).
With the aircore method, quick and accurate mineral exploration can be carried out to depths of around 100 metres. Compressed air is forced down between the inner and outer drill rod to operate a venturi vacuum system at the face of the drill bit.
This subsequently carries uncontaminated samples up through the inner tube to the cyclone which distributes cuttings at the bottom of the cyclone and releases the air into the atmosphere.
Dual tube RC in its numerous forms has many sampling and exploration uses.
Geotechnical Drilling is carried out to determine soil and rock characteristics and in some cases, gather information about the nature and position of the water table from particular sites. Drilling is conducted to assess potential construction sites and to confirm conditions.
It is important to have the detailed information of soil and rock properties obtained from Geotechnical Drilling so that buildings or tunnels are not place on top or cut through, unstable or weak material.
Geotechnical drilling precedes foundation and construction drilling: i.e.
- Buildings and storage facilities
- Factories and plants
- Dams, bridges and roads
- Wharves and civil work
- Tunnels and shafts
- Access or inspection holes
- Power stations