At the Exploration stage, an explorer will investigate whether a commercial quantity and quality of a mineral or petroleum exist in the area of its Exploration Licence. The explorer may undertake higher-impact exploration and may seek access to your land. Before a mineral or petroleum explorer can explore on your land, it must negotiate a Land Access Arrangement with you. Before an explorer can move from the Exploration stage to the Production stage, it must pass through the Gateway Process stage, receive development consent, receive other environmental approvals, and apply for and be granted a production title (such as a Mining Lease).
Steps at the exploration stage
There are a number of steps at the Exploration stage which may be followed by a mineral or petroleum explorer in the area of its Exploration Licence.
The explorer may undertake low-impact activities following access approval but will be required to receive additional approvals for higher-impact exploration activities it plans, such as by lodging an activity assessment application or by preparing a Review of Environmental Factors or an Environmental Impact Statement. The explorer may also need to prepare an Agricultural Impact Statement.
Once approval has been obtained, the explorer will then employ exploration techniques in a staged way that will generally escalate from low impact to higher impact as the exploration activity progresses.
Environmental assessment and approval before exploration activity can occur
The State Environmental Planning Policy (Mining, Petroleum Production and Extractive Industries) 2007 (Mining SEPP) provides that mineral exploration (and fossicking) is development permissible without consent and is therefore subject to assessment under Part 5 of the Environmental Planning and Assessment Act 1979 (Planning Act). The NSW Division of Resources & Energy is the determining and approval authority for all exploration proposals.
An exploration title (such as an exploration license) for minerals or petroleum is subject to a statutory condition that the title holder must not carry out an “assessable prospecting operation” unless an exploration activity approval has been obtained.
Assessable prospecting operation means any exploration activity that is not exempt development within the meaning of clause 10 of the (Mining SEPP).
Certain exploration activities with minimal environmental impact have been identified as exempt development under the Mining SEPP. These minimal impact activities do not require further environmental assessment or approval prior to being carried out.
Under the Mining SEPP the following activities are exempt development, provided they are of minimal environmental impact:
the construction, maintenance and use of equipment for the monitoring of weather, noise, air, groundwater or subsidence,
low intensity exploration activities, including:
geological mapping and airborne surveying;
sampling and coring using hand-held equipment;
geophysical (but not seismic) surveying and downhole logging; and
accessing of areas by vehicle that does not involve the construction of an access way, such as a track or road.
These activities can be undertaken without approval provided that they are on land that:
is not within an environmentally sensitive area of State significance; or
is within a state conservation area, but is not otherwise on land referred to in section 3 of the Mining SEPP as being environmentally sensitive area of State significance.
Assessable Prospecting Operations
All "assessable prospecting operations" require further approval from the Department before they can be carried out. Assessable prospecting operation means any exploration activity that is not exempt development within the meaning of clause 10 of the Mining SEPP.
Exploration Activity Application and Assessment Process
Application Form and Lodgement
Applications for exploration activity approvals must be made using the Department's Application Form. The Application Form asks specific questions about the proposed activity, with the answers identifying whether the level of assessment required. The Application Form also identifies when additional supporting information must be submitted to satisfy relevant statutory requirements.
Assessment and Determination
For more information as to the requirements for obtaining approval to carry out activities refer to ESG5: Guideline for the Assessment and Determination of Exploration Activities.
The application process for exploration activities is summarised below.
Common Exploration Activities (excludes petroleum)
In order to streamline the assessment process, a subset of activities requiring approval (being Assessable prospecting operations) have been identified as being unlikely to have a significant environmental impact if carried out in a particular manner. These activities are referred to as Common Exploration Activities (CEAs). Any petroleum exploration activities are specifically excluded from being CEAs.
A streamlined assessment pathway has been developed for these activities. These activities can be assessed under the streamlined CEAs Assessment Pathway if they:
satisfy location requirements set out in ESG5: Assessment Requirements for Exploration Activities;
satisfy the impact thresholds and criteria set out in ESG5: Assessment Requirements for Exploration Activities; and
can be carried out in accordance with the relevant Department's Codes of Practice for Exploration.
Non-Common Exploration Activities
Applications to undertake Assessable Activities which do not meet the CEA criteria must be accompanied by additional environmental impact assessment information. The Application Form identifies the specific additional supporting information required by the Department to facilitate the environmental assessment.
The additional information can be provided in the form of:
Targeted REF – A Targeted REF would generally be suitable for activities that only slightly deviate from one or more of the CEA criteria. The information in a Targeted REF only needs to specify the potential environmental impacts associated with the departure(s) from the relevant CEA location restriction, impact criteria, or management control; or
Guideline REF – prepared in accordance with the Department's ESG2: Guidelines for Preparing a Review of Environmental Factors (DRE, 2015). This may be appropriate for activities which significantly depart from the CEA criteria, but are not likely to have a significant impact on the environment. A Guideline REF is the minimum required for all petroleum exploration activities; or
Environmental Impact Statement (EIS) or Species Impact Statement (SIS) - An EIS will be required for activities likely to significantly affect the environment, and a SIS will be required where the activity will be carried out in critical habitat, or is only likely to have a significant impact on a threatened species, population or ecological communities or their habitats. Where an EIS is required there may be an additional requirement for an Agricultural Impact Statement (AIS)
For more information on Environmental Assessment of Exploration Activities see:
For more information on AISs for exploration activities see:
Assessment of an Agricultural Impact Statement
An Agricultural Impact Statement is a risk-based assessment of the impact of a proposed mining or petroleum development on agricultural land, water and farming businesses. An Agricultural Impact Statement is required at both the exploration and the production stages before a mineral or petroleum project is able to be approved.
For more information on agricultural impact statements see the page:
Assessment under the Aquifer Interference Policy
Just as landholders and other users of water in NSW are subject to water licensing requirements, the mineral and petroleum industries must account for the water they take from the State’s water supply and must obtain licences which account for that take where the take is more than 3 megalitres a year.
Any ‘aquifer interfering activities’ planned as part of the exploration must also be assessed under the Aquifer Interference Policy to ensure they do ‘no more than minimal harm’ to groundwater resources.
For more information on the Aquifer Interference Policy see the page:
Land access for environmental assessment
The explorer may approach you for access to your land to assess the area to prepare an environmental impact assessment.
For mineral exploration, the explorer can also apply to the Minister for Industry, Resources and Energy for a permit which allows entry to your property for environmental assessment. Such a permit allows entry to your property for environmental assessment but not to undertake exploration activities.
For petroleum exploration, the explorer does not have the option of applying for a permit to access to your land to undertake environmental assessment. The explorer may still approach you to negotiate a land access arrangement to undertake environmental assessment.
For more information on land access see the chapter:
Land access for exploration
Before an explorer can conduct any exploration activity on your land, the explorer must first negotiate a land access arrangement with you.
For more information on land access see the page:
Types of exploration activities – coal and minerals
There are a range of activities that may be undertaken as part of an exploration program. These activities are dependent on a number of factors, including the nature of the mineral being sought and the geology of the area.
Exploration generally starts from low impact activities to determine whether signs of minerals are evident before progressing to more intensive and costly activities like drilling and bulk sampling.
Exploration activities may include:
Geological mapping is typically undertaken by a geologist who observes the location, orientation and characteristics of rocks or sediments exposed at the land surface. This information can then be used to prepare a geological map of the exploration area which records the rock types and structures.
Geochemical surveys usually involve the collection of soil, rocks and/or sediment samples. These samples are sent for chemical analysis at a laboratory.
Soil sampling is usually undertaken using hand-held tools such as shovels, picks and hand augers to collect samples of soil and subsoil. Samples are usually collected on a regular grid pattern and involve collection of small (approximately one kilogram) samples. Holes excavated during the program are typically back-filled immediately following sampling.
Stream sediment sampling
Stream sediment sampling involves collection of approximately two kilogram samples of sediment within drainage lines. Three samples are usually taken at the junction of two creeks: one downstream of the junction and two upstream of the junction (in each of the merging drainage lines). Samples are typically extracted using hand tools and may be sieved during collection.
Rock chip sampling
Rock chip sampling involves collecting up to a few kilograms of rock material using hand-held tools. Rock chip samples will usually be collected during geological mapping programs.
Channel sampling involves the collection of a series of samples of rock or soil along a line. This may be a road cutting, the face of an open-cut or underground mine, a costean or similar.
Costean or trench sampling
Costean or trench sampling involves digging a costean or trench using a backhoe, ‘ditch witch’ or similar equipment. The costean or trench may range from 20cm wide to more than a metre, and from a few centimetres deep (where hard rock is near the surface) to metres deep. The edges of the trench are typically mapped geologically and channel samples collected.
Geophysical surveys assist in mapping different rock types and can help identify resources without the need for direct observation. Different geophysical surveys measure different physical properties of the earth and have different applications and equipment. Geophysical surveys can be conducted from the air, on land, and down drill holes. Geophysical surveys include airborne surveys and ground-based surveys.
Airborne geophysical surveys include magnetic, radiometric, gravity or electromagnetic surveys. These surveys provide general geological information for an area and are often used in the initial stages of exploration. These surveys are typically undertaken using low flying helicopters or light aircraft which fly in a grid pattern. The instruments may be either mounted on the aircraft or towed underneath a helicopter.
Depending on the type of survey, the aircraft may fly between 25 and 60 metres above the ground, with flight lines spaced between 25 and 200 metres apart.
Seismic surveys measure variation in reflected ground vibration as it passes through the earth. The surveys use an energy source to create high frequency vibrations, which can be truck-mounted vibrating weights or a simple hammer hit depending on the scale of the survey. Small sensors are linked by cables and spread either side of the source to detect and relay the vibrations as they return to the surface. Seismic surveys provide information about rocks down to depths of several kilometres and are particularly suited to flat-lying sedimentary basins. They are most often used in petroleum and coal exploration.
Magnetic surveys measure the variations of the Earth's magnetic field due to the presence of magnetic minerals. Subtle variations in the abundance of magnetic minerals are used to interpret rock types and can assist in identifying resources.
These surveys are typically undertaken by a geophysical technician on foot carrying a magnetometer and a sensor on a pole. They are most often used in metallic mineral exploration.
Radiometric surveys measure gamma rays which are continuously being emitted from the earth by natural decomposition of some common radiogenic minerals.
The surveys focus on recording the isotopes of potassium, thorium and uranium. Generally most gamma rays emanate from the top 30 centimetres of rock or soil which can detected by airborne surveys or on surface rocks using a hand-held spectrometer. They are most often used in metallic and industrial mineral exploration.
Gravity surveys measure the earth’s gravity field measured with a gravimeter to determine variations in rock density in the earth’s crust. Ground gravity surveys require a geophysical technician to take gravity measurements at set intervals of distance and record the precise height at each location. Access to the recording sites can be by vehicle or helicopter, depending upon remoteness.
Induced Polarisation surveys induce an electric field in the ground and measure the chargeability and resistivity of the subsurface. The technique can identify differences in resistivity arising from aquifers, metallic minerals and stratigraphy. Readings are taken by a small crew who shift a ground array of transmission and receiver cables. Induced polarisation surveys are most often used in metallic mineral exploration.
Electromagnetic (EM) surveys induce an electromagnetic field and measure the three dimensional variations in conductivity within the near-surface soil and rock. Conductive units can be studied to locate metallic minerals, and to understand groundwater and salinity. Ground readings are taken by a small crew who shift a ground array of transmission and receiver cables. They are most often used in metallic mineral exploration.
Drilling is often conducted as part of an exploration program to obtain detailed information about the rock below the surface of the ground. The drilling method used depends on the type of rock and information sought. The degree of disturbance around the hole varies with each method. Drill sites are required to be rehabilitated after the completion of drilling.
Auger Drilling uses either a hand-held power auger or one mounted on a small vehicle. It is not dissimilar to a post-hole digger used by farmers when fencing.
Air Drilling – there are two main air drilling methods, air-core and rotary air blast. These methods usually involve a utility or small truck mounted rig with an air compressor carried onboard or towed separately. This type of drilling creates rock fragments (chips). These are removed from the drill hole by compressed air, which is forced down the drill hole and lifts the rock chips to the surface. This type of drilling requires minimal site preparation and rehabilitation.
Air Drilling – there are two main types of air drilling used to drill deeper holes, namely open hole percussion and reverse circulation. These methods usually involve truck mounted rigs with one or two support vehicles to carry drill rods and air compressor equipment. These drilling techniques produce rock chips that are lifted to the surface by compressed air and do not necessarily require significant site preparation and rehabilitation.
Diamond Drilling – a truck mounted rig with support vehicles is used to extract a continuous cylinder of rock. Diamond drilling involves the use of water and drilling fluids that are contained in either an in-ground sump or above ground tanks, and requires significant site preparation and rehabilitation. Most exploration for coal and minerals uses a combination of diamond and reverse circulation drilling.
Rotary mud drilling
Rotary mud drilling is most often used for deep stratigraphic drilling. This method produces fine rock fragments and uses water and drilling fluids to lubricate the drill bit and return the rock fragments to the surface. The drilling fluids are contained in either in-ground sumps or above ground tanks. The drilling rigs are usually larger than for other methods and require more support vehicles and site preparation.
Bulk sampling operations
Prior to making a decision to apply to develop a mine, an explorer may extract a bulk sample of the material to be mined to allow further testing and refinement of the proposed mining procedures. Extraction of a bulk sample in NSW requires approval from the NSW Trade & Investment Division of Resources and Energy. The extraction of large samples may also require approval from the Department of Planning and Environment.
Types of exploration activities – petroleum
As with mineral and coal exploration, activities for petroleum exploration will tend to escalate from low-impact exploration activities to higher-impact activities.
In the exploration and appraisal stages for petroleum, the explorer may conduct the following activities:
desktop studies and review of existing data
drilling core holes, and
Desktop studies examine geological and geophysical data publicly available from the NSW Government, data submitted to Government by other explorers, or data obtained commercially from other explorers.
For more information on desktop studies and sources of geophysical information see the page:
Seismic surveys are used to map the geology of the local area to locate any potential petroleum reserves.
The explorer will mark out a line along which the survey will take place. Pegs will be used to mark out the survey points, and cables and geophones will be laid along the line. Cables are connected to a truck which contains the measuring equipment required for the survey.
Core-holes are drilled to analyse the depth and composition of a coal seam. Core-holes are cylinders of solid rock which are extracted from the ground.
Drilling will require a drilling-rig. Core holes are between 100 to 300 millimetres in diameter taken from up to 1500 metres deep.
A core hole may take up to 4 weeks to drill.
If a petroleum resource has been identified and could be economically viable, then the explorer may seek to conduct pilot testing on your land. This is a test-run of petroleum production.
Pilot testing will generally involve drilling up to 5 wells, approximately 0.25 to 1.5km apart. Any gas produced from pilot testing will usually be ‘flared’ (or burned) via a flare vent.
At this stage it is most likely that produced wastewater will be held in tanks at the side of the well before being transported to a holding dam or treatment facility.
If the explorer believes that the resource beneath your land is not economically viable, and during exploration there has been any clearing of vegetation or drilling, you can expect:
drill holes to be plugged,
costeaning trenches or bulk sampling pits to be filled, and/or
revegetation if there was clearing.
Application for a Mining Lease or Petroleum Production Lease
If the explorer believes that the resource beneath your land is economically viable for extraction, to move from the exploration stage to the Pre-Exploration/ Development Application Stage and to produce minerals or petroleum, the explorer may first have to pass through the Mining and Petroleum Gateway Process stage and will need to apply for and be granted a Mining Lease or a Petroleum Production Lease.
 NSW Government Environmental Management Guidelines for Industry – EDG10: Surface Disturbance Notice for Exploration Activities (NSW Trade and Investment Division of Resources and Energy, August 2011)
 Mining Act 1992 (NSW) s 252
 NSW Government Land Access Arrangement Information for Mineral Exploration (NSW Trade and Investment Division of Resources and Energy, June 2013)
 Santos Seismic Survey Factsheet (April 2013)
 Santos Coal Seam Gas Overview Factsheet (November 2012)