There are questions many people who are curious to know more about mining, relating to what’s involved, and how miners go about taking minerals out of the ground.

We have made an attempt to bring these questions together into one place, and answer.

Please get in touch with Minerals West Coast if you think something has been missed.

What permissions are needed to mine in New Zealand?

Mining and quarrying in New Zealand are partly governed by the Crown Minerals Act 1991. The CMA provides for the granting of rights to prospecting and exploring for, and mining of, Crown owned minerals within defined areas. They take the form of minerals prospecting, exploration, and mining permits, and apply in respect of all gold, silver, uranium and petroleum, and all minerals on Crown-owned land (including the seabed), and land alienated from the Crown under certain legislation. The exception is pounamu / greenstone, which is owned by Ngāi Tahu iwi under a 1997 statute.

The Crown minerals regulator is a unit of the Ministry of Business, Innovation and Employment, with the name of New Zealand Petroleum & Minerals.

By themselves, Crown minerals permits do not authorise minerals activities. Prospectors, explorers and miners will need to comply with a potential raft of other legislation and regulation.

The most significant requirement is under the Resource Management Act 1991, which in almost all cases requires resource consent for the “sustainable management” of minerals activities. To apply for resource consent will require an approach to the relevant district and regional council, or a unitary council. The RMA covers minerals activities on land, and in the “coastal marine area”, which is the sea out to 12 nautical miles or 22 kilometres from shore.

Minerals exploration and mining of the seabed between 22km and 185km from shore is regulated under the Exclusive Economic Zone and Continental Shelf (Environmental Effects) Act 2012, which provides for project proponents to apply for marine consent to manage environmental effects. The regulator is the Environmental Protection Authority.

To gain physical access to land requires an “access arrangement” under the CMA in the case of Crown land, eg public conservation land or the coastal marine area, from the minister of energy and resources, and the relevant land-holding minister. If it’s private land, the minerals proponent will need to arrange access with the landowner, and this is usually on commercial terms.

Where the Crown does not own the minerals, someone else does. That person could be the landowner, or some other person. The only way to find out is a painstaking search on the property register which Land Information New Zealand administers. For its part, the Crown does not always know if it owns the minerals at a specific place – the onus is on the would-be explorer or miner to find that out.

In the case of conservation land, there is a misconception that prospectors, explorers and miners do not need a concession under the Conservation Act 1987. This is not correct. Some minerals-related activities occurring outside of the area of the Crown minerals permit will, in practice, require a concession. That could include an access road to and from a mine site, or the location of a waste rock stack or administration buildings, or quarrying access to river gravels across a marginal strip (administered by the Department of Conservation) or an esplanade reserve.

Explorers and miners may disturb indigenous fauna classified as “wildlife” under the Wildlife Act 1953. In addition to the environmental management conditions under a resource consent, access arrangement, and potentially also a concession, separate authorisation to disturb wildlife may also be needed. Typical examples are individual kiwi, landsnails, and lizards. DOC is the regulator.

Under a wildlife permit – as this regulatory approval is often called – the explorer or miner may also need to comply with the Animal Welfare Act 1999. The regulator is a national animal ethics advisory committee set up by the Ministry for Primary Industries.

Mining today often occurs where mining was done in the past, and where there is now mining heritage. The modification or disturbance of heritage is regulated under the Heritage NZ Pouhere Taonga Act 2014, which replaced the earlier historic places act. An affected explorer or miner will need to apply for an authority from the regulator, Heritage NZ Pouhere Taonga.

Besides the above, an explorer or miner may need to comply with certain other legislation such as the Building Act 2004 (eg for tailings empoundments); the Health and Safety at Work Act 2015; in rare cases, the Reserves Act 1977; coal miners will need to comply with the Climate Change Response Act 1992 (New Zealand Emissions Trading Scheme); and in the case of overseas-owned companies, the Overseas Investment Act 2005. A seabed explorer or miner will also need to comply with the Marine Mammals Protection Act 1978.


What happens to mine sites when mining is completed?

When all economically recoverable resources at any one point in time have been extracted, a mine can be said to have reached the end of its productive life.

In many instances, the people mining the land won’t be the landowners; in that case, miners’ presence on the land is by way of an access agreement with the landowners.

For privately held land (most likely farmland or exotic forestry land), the land will be returned to its former condition and use, agreed between the miner and the landowner once mining has completed.

In the case of publicly owned land, such as public conservation land, the miner will be required to restore and rehabilitate the land to the satisfaction, in this case, of the minister of conservation, or his or her staff in the Department of Conservation under delegated authority. In the case of other Crown land, the responsibility would lie normally with the minister for land information.

Miners lodge bonds (under the Resource Management Act 1991, and under the Crown Minerals Act 1991 in the case of mining on Crown land) prior to mining (much like any other tenant) to give security to the minister that rehabilitation will occur. These will be a condition of a resource consent, and/or access arrangement.

Rehabilitation requires reshaping or recontouring disturbed land to as close to its original form as possible, or to a desired or agreed landform, as well as distributing topsoil in which plants can grow, followed by replanting or reseeding,  spreading slash (tree branches, trunks etc) to guard against erosion and to provide perching sites for birds to promote the spread of seed for natural revegetation.

An environmental benefit arises from repurposing some or most waste rock / overburden as backfill in underground mines, or to fill in areas excavated during mining. This type of land use is essentially a “cleanfill”, a common outcome of earthworks in New Zealand, and which qualifies as part of the “circular economy”.

A former mine pit may become ultimately a lake or wetland; also the case for a former tailings empoundment – these are “engineered landforms” often required to comply with the Building Act 2004.  

In other instances, “vegetation direct transfer” will be used – this is where mine environmental staff remove layers of vegetation in large clumps (to retain the topsoil and root structure of ecosystems).

Depending on the conservation values of mined areas, timelines for rehabilitation vary. It will clearly take longer to re-establish old-growth forest than regenerating mānuka and kānuka-dominated forest.

The usual priority is the re-establishment of ecosystem function – i.e. to reach a point at which the land can be left to its own devices to allow native plants and animals to recolonise and thrive, species will inhabit and reproduce within the area, without disturbance from introduced plants and animals.

An additional consideration is freshwater management. Miners will usually need to manage discharges from mined and/or rehabilitated land to levels established under resource consent or other regulatory approvals. In the case of coal mining for example, the risk can arise of acidic discharges to water, and where that occurs, there can be elevated levels of dissolved aluminium or iron, which can be toxic to instream wildlife. In some cases, miners take responsibility also for the discharges from historic abandoned mines (known as orphan discharges).  

On the completion of land rehabilitation to an agreed standard between the miner and the minister of conservation (or his or her staff), DOC-held bonds are returned to the miner. 

Why are people still mining coal?

People are still mining coal because other people still need it as a cost-effective or irreplaceable source of energy, as heat or steam, or as back-up for national grid electricity generation. In 2022 the world consumed about 8 billion tonnes of coal.

New Zealand produces about 3 million tonnes per year (0.04% of global supply), and of which more than  1 million tonnes are exported. In some years up to 1 million tonnes are also imported, noting this is a highly variable figure, depending, for example, on international coal prices, and the size of the stockpile at the Huntly power station.

Besides electricity generation, coal is used in New Zealand to manufacture iron and steel, cement and lime, as a source of energy for dairy factories and freezing works, as a source of heat and supply of CO2 into commercial greenhouses year-round, and for space heating, e.g. in hospitals and schools.

A related question is: when will the coal run out? Estimates for easily accessed coal worldwide run into around 1 trillion tonnes. At global annual consumption of 8 billion tonnes, it would take 125 years to deplete this coal, and then there is a much larger coal resources that is currently more difficult to access, but which in the future will inevitably be available for extraction and use.

Why do people mine on conservation land?

In short, because that’s where economically viable deposits of many or most mineral resources are located. Mining occurs on privately and publicly owned land, but understandably people have concerns about the impact and footprint of mining on public conservation land.

It is a truth that should be universally acknowledged that minerals can only be mined where they are found, and minerals happen to be found in some areas of public conservation land, a very small area of land.

As New Zealand has been inhabited by a growing number of people over the past 700 to 800 years, we have populated and settled in the flatter, low-lying, and fertile parts of the country.

As a result, much of what remains of our once widespread forests, wetlands, and other wild places is concentrated in steeper and more mountainous terrain, and these areas have come to make up the majority of land set aside for conservation – i.e. there is a strong positive correlation between conservation land and mountains.

Simultaneously, economic deposits of mineral resources also tend to be found in geologically active areas where coal seams, quartz reefs, and other concentrations of minerals can be found – so there is a correlation between mountains and minerals. It is no accident that the word “ore”, meaning minerals-rich rock or earth, stems from the Greek word for mountain, “oros”.

As a result, there is a positive correlation between conservation land and the location minerals. This means miners are likely to want to at least look for minerals on conservation land, and then at least apply for access to mine minerals on conservation land, if they happen to find them.

Having said all that, since 1987, mining has disturbed about about 0.04% of all public conservation land – four hectares out of 10,000, or 3,500 hectares out of the total 8.8 million-hectare public conservation estate.

It’s hard to imagine a percentage as small as 0.04%. Let’s try. One percent is one-hundredth of something. It’s 1 centimetre out of 1 metre. The 0.04% amounts to four-tenths of 1 millimetre, in a ruler that is 1m long. Vanishingly small.

Even if a government were to enable access to conservation land for mining, only a very small fraction of that land could ever be mined – economically. Given the ability today to rehabilitate mined land to very high standards, the mining industry would argue: if it’s responsible, we should be able to mine, anywhere.

Of course, there are exceptions to this line of thought. No one is suggesting that anyone mine the top of Aoraki/Mt Cook. Or Cathedral Cove in the Coromandel. Or, close to the West Coast, Punakaiki/Pancake Rocks.

If you have read this far, here’s a question for you, and please let us know your answer: how many gold or coal mines have you ever seen in the course of your life?