Water is considered mining’s biggest casualty of all time given the huge scale at which mining of different types are advancing in today’s world. Acid mine drainage (AMD) is one of the largest repercussions of mining on water resources. It is a risk associated with all kinds of hardrock mines for extraction of useful metals and a significant number of coal mines suffer from acid mine drainage.
What is acid mine drainage?
As the name suggests, it is the outflow of acidic water from mining areas. It is identified by appearance of brownish-yellow precipitate with a foul smell and increase in acidity of water. Target ores for metals such as gold, copper, silver etc. or coal sometimes are sulphur bound which are known as ‘metal sulphides’.
Acid mine drainage is most commonly caused by iron sulphide called “pyrite” or “fool’s gold” which is abundantly found with almost all the metal ores. These sulphides are exposed during mining, and undergo oxidation reaction in presence of air and water to form sulphuric acid that is corrosive. The acid run off further dissolves harmful metals such as copper, aluminium, manganese, mercury, lead etc. and poison the ground or surface water system.
Acid mine drainage is an irreversible process that turns undisturbed and relatively unreactive ores into volumes of hazardous waste whose containment is extremely difficult once it reaches a water body. Acid drainage can also occur in non-mining areas such as construction sites, artificially dug areas or naturally weathered rocks termed as ‘acid rock drainage’. The process of pyrite oxidation and acid formation can be further catalysed by bacteria called as ‘extremophiles’ which can thrive in extreme conditions such as acidic environment.
Environmental impacts of acid mine drainage
Acid mine drainage can occur indefinitely for hundreds of years even after the mining activities have ended and thus affects a large horizon – ecologically and economically. The mines continue to produce acidic drainage as long as the rocks are exposed or become devoid of acid producing minerals. It is one of the single biggest non-point sources of pollution.
Some Roman mining sites in Great Britain are still producing problematic acid mine drainage, 2000 years after the stoppage of mining (CNHE, 2017). Moreover, AMD can develop at any point of the mining process – underground working, open pit mine faces, waste rock dumps, tailings deposits and ore stockpiles. In India, acid mine drainage usually comes from coal mines.
Most of the living organisms thrive well in the pH of near neutral which is 7. Acid mine drainage in some of the worst cases could decrease the pH of water to as low as less than 3. Thus it degrades streams, rivers and aquatic life forms in varying degrees depending upon the severity of pH change. It limits the growth of the river ecology in addition to unsuitable use of water for human, agriculture, industrial and recreational activities.
The increase in acidity can cause loss of sodium ions from the blood of fishes, which adversely affects the gill’s function. Prolonged exposure to low pH can be lethal for plants and animals with effects such as stunted growth, lesions, low reproductive rates and deformities (Vyawahre and Rai, 2016). Acid mine drainage is also responsible for loading a huge amount of heavy metals like lead, aluminium, manganese and more into our waterways. Aluminium is toxic to many aquatic animals and limits root development in plants leading to nutrient deficiency.
In addition to increase of acidity and release of toxic metals, neutralisation of the acid water by alkaline rocks could create an additional problem. In case of decrease in acidity, the iron which was in ferrous form turns into ferric and comes out of the water as a yellowish precipitate (solid) called ‘yellowboy’. It effectively chokes the streambed, crevices and prohibits the growth of benthic (bottom dwelling) life forms.
AMD have renouncing affects on the quality of groundwater system if the mines are located in permeable soil formations. The acidic and heavy metal containing water may percolate inside the water aquifers (underground water pockets) and gets spread throughout the underground water system which ultimately reaches human consumption via bore wells.
Prevention, mitigation and treatment of acid mine drainage
Acid mine drainage does bear a significant economic cost and irreversible environmental effects. Prevention of the acid-generating processes seems to be the only way to completely wipe out the problem of acid mine drainage but, stopping of mining is not the viable solution in most cases.
However, sulphuric acid could be stopped from forming by preventing the waste rock and mine tailings to come in contact with air by strategies such as submerging the tailings under water, sealing them behind barriers or burying them underground (groundtruthseeking.org, 2010). Nonetheless, isolating and containing huge amount of the generated waste is practical either above or below ground thus storing it for a future possibility or treating them with the help of technological advancement.
In most cases it is impossible to completely treat the contaminated water from acid mine drainage due to its high cost, inefficient technology and easily diffusible quality of water. But, its consequences could be limited by treating the water before releasing it into the environment through passive and active technologies (Johnson and Hallberg, 2005).
- Passive Treatment- It is the use of naturally occurring biological and chemical reactions that could be employed to reduce the acidity of AMD. For example, ‘bioreactors’ which works on use of sulphate-reducing microbes that precipitate out dissolved harmful metals. Another method is the creation of artificial wetlands where microbes can remove the heavy metals from the mine water. Both these methods are limited to small scale mines since it is expensive and requires a huge area of land. However, operation and maintenance of passive treatment system is comparatively lesser as compared to active treatment.
- Active Treatment- It is the typical water treatment system involving the use of alkaline chemicals such as caustic soda, hydrated lime, sodium carbonate etc. to decrease the acidity of mine drainage. Limestone is one very common chemical used due to its low cost and relative abundant availability. On the other hand, continued active treatment due to precipitation increases the rate of total dissolved solid (TDS) which is an important water quality parameter. Moreover, active treatment technologies are expensive due to chemical usage, equipments and huge manpower.
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The United Nations has shaped so much of global co-operation and regulation that we wouldn’t recognise our world today without the UN’s pervasive role in it. So many small details of our lives – such as postage and copyright laws – are subject to international co-operation nurtured by the UN.
In its 75th year, however, the UN is in a difficult moment as the world faces climate crisis, a global pandemic, great power competition, trade wars, economic depression and a wider breakdown in international co-operation.
Still, the UN has faced tough times before – over many decades during the Cold War, the Security Council was crippled by deep tensions between the US and the Soviet Union. The UN is not as sidelined or divided today as it was then. However, as the relationship between China and the US sours, the achievements of global co-operation are being eroded.
The way in which people speak about the UN often implies a level of coherence and bureaucratic independence that the UN rarely possesses. A failure of the UN is normally better understood as a failure of international co-operation.
We see this recently in the UN’s inability to deal with crises from the ethnic cleansing of the Rohingya Muslims in Myanmar, to civil conflict in Syria, and the failure of the Security Council to adopt a COVID-19 resolution calling for ceasefires in conflict zones and a co-operative international response to the pandemic.
The UN administration is not primarily to blame for these failures; rather, the problem is the great powers – in the case of COVID-19, China and the US – refusing to co-operate.
Where states fail to agree, the UN is powerless to act.
Marking the 75th anniversary of the official formation of the UN, when 50 founding nations signed the UN Charter on June 26, 1945, we look at some of its key triumphs and resounding failures.
Five successes
1. Peacekeeping
The United Nations was created with the goal of being a collective security organisation. The UN Charter establishes that the use of force is only lawful either in self-defence or if authorised by the UN Security Council. The Security Council’s five permanent members, being China, US, UK, Russia and France, can veto any such resolution.
The UN’s consistent role in seeking to manage conflict is one of its greatest successes.
A key component of this role is peacekeeping. The UN under its second secretary-general, the Swedish statesman Dag Hammarskjöld – who was posthumously awarded the Nobel Peace prize after he died in a suspicious plane crash – created the concept of peacekeeping. Hammarskjöld was responding to the 1956 Suez Crisis, in which the US opposed the invasion of Egypt by its allies Israel, France and the UK.
UN peacekeeping missions involve the use of impartial and armed UN forces, drawn from member states, to stabilise fragile situations. “The essence of peacekeeping is the use of soldiers as a catalyst for peace rather than as the instruments of war,” said then UN Secretary-General Javier Pérez de Cuéllar, when the forces won the 1988 Nobel Peace Prize following missions in conflict zones in the Middle East, Africa, Asia, Central America and Europe.
However, peacekeeping also counts among the UN’s major failures.
2. Law of the Sea
Negotiated between 1973 and 1982, the UN Convention on the Law of the Sea (UNCLOS) set up the current international law of the seas. It defines states’ rights and creates concepts such as exclusive economic zones, as well as procedures for the settling of disputes, new arrangements for governing deep sea bed mining, and importantly, new provisions for the protection of marine resources and ocean conservation.
Mostly, countries have abided by the convention. There are various disputes that China has over the East and South China Seas which present a conflict between power and law, in that although UNCLOS creates mechanisms for resolving disputes, a powerful state isn’t necessarily going to submit to those mechanisms.
Secondly, on the conservation front, although UNCLOS is a huge step forward, it has failed to adequately protect oceans that are outside any state’s control. Ocean ecosystems have been dramatically transformed through overfishing. This is an ecological catastrophe that UNCLOS has slowed, but failed to address comprehensively.
3. Decolonisation
The idea of racial equality and of a people’s right to self-determination was discussed in the wake of World War I and rejected. After World War II, however, those principles were endorsed within the UN system, and the Trusteeship Council, which monitored the process of decolonisation, was one of the initial bodies of the UN.
Although many national independence movements only won liberation through bloody conflicts, the UN has overseen a process of decolonisation that has transformed international politics. In 1945, around one third of the world’s population lived under colonial rule. Today, there are less than 2 million people living in colonies.
When it comes to the world’s First Nations, however, the UN generally has done little to address their concerns, aside from the non-binding UN Declaration on the Rights of Indigenous Peoples of 2007.
4. Human rights
The Human Rights Declaration of 1948 for the first time set out fundamental human rights to be universally protected, recognising that the “inherent dignity and of the equal and inalienable rights of all members of the human family is the foundation of freedom, justice and peace in the world”.
Since 1948, 10 human rights treaties have been adopted – including conventions on the rights of children and migrant workers, and against torture and discrimination based on gender and race – each monitored by its own committee of independent experts.
The language of human rights has created a new framework for thinking about the relationship between the individual, the state and the international system. Although some people would prefer that political movements focus on ‘liberation’ rather than ‘rights’, the idea of human rights has made the individual person a focus of national and international attention.
5. Free trade
Depending on your politics, you might view the World Trade Organisation as a huge success, or a huge failure.
The WTO creates a near-binding system of international trade law with a clear and efficient dispute resolution process.
The majority Australian consensus is that the WTO is a success because it has been good for Australian famers especially, through its winding back of subsidies and tariffs.
However, the WTO enabled an era of globalisation which is now politically controversial.
Recently, the US has sought to disrupt the system. In addition to the trade war with China, the Trump Administration has also refused to appoint tribunal members to the WTO’s Appellate Body, so it has crippled the dispute resolution process. Of course, the Trump Administration is not the first to take issue with China’s trade strategies, which include subsidises for ‘State Owned Enterprises’ and demands that foreign firms transfer intellectual property in exchange for market access.
The existence of the UN has created a forum where nations can discuss new problems, and climate change is one of them. The Intergovernmental Panel on Climate Change (IPCC) was set up in 1988 to assess climate science and provide policymakers with assessments and options. In 1992, the UN Framework Convention on Climate Change created a permanent forum for negotiations.
However, despite an international scientific body in the IPCC, and 165 signatory nations to the climate treaty, global greenhouse gas emissions have continued to increase.
Under the Paris Agreement, even if every country meets its greenhouse gas emission targets we are still on track for ‘dangerous warming’. Yet, no major country is even on track to meet its targets; while emissions will probably decline this year as a result of COVID-19, atmospheric concentrations of greenhouse gases will still increase.
This illustrates a core conundrum of the UN in that it opens the possibility of global cooperation, but is unable to constrain states from pursuing their narrowly conceived self-interests. Deep co-operation remains challenging.
Five failures of the UN
1. Peacekeeping
During the Bosnian War, Dutch peacekeeping forces stationed in the town of Srebrenica, declared a ‘safe area’ by the UN in 1993, failed in 1995 to stop the massacre of more than 8000 Muslim men and boys by Bosnian Serb forces. This is one of the most widely discussed examples of the failures of international peacekeeping operations.
On the massacre’s 10th anniversary, then UN Secretary General Kofi Annan wrote that the UN had “made serious errors of judgement, rooted in a philosophy of impartiality”, contributing to a mass murder that would “haunt our history forever”.
If you look at some of the other infamous failures of peacekeeping missions – in places such as Rwanda, Somalia and Angola – it is the limited powers given to peacekeeping operations that have resulted in those failures.
2. The invasion of Iraq
The invasion of Iraq by the US in 2003, which was unlawful and without Security Council authorisation, reflects the fact that the UN is has very limited capacity to constrain the actions of great powers.
The Security Council designers created the veto power so that any of the five permanent members could reject a Council resolution, so in that way it is programmed to fail when a great power really wants to do something that the international community generally condemns.
In the case of the Iraq invasion, the US didn’t veto a resolution, but rather sought authorisation that it did not get. The UN, if you go by the idea of collective security, should have responded by defending Iraq against this unlawful use of force.
The invasion proved a humanitarian disaster with the loss of more than 400,000 lives, and many believe that it led to the emergence of the terrorist Islamic State.
3. Refugee crises
The UN brokered the 1951 Refugee Convention to address the plight of people displaced in Europe due to World War II; years later, the 1967 Protocol removed time and geographical restrictions so that the Convention can now apply universally (although many countries in Asia have refused to sign it, owing in part to its Eurocentric origins).
Despite these treaties, and the work of the UN High Commission for Refugees, there is somewhere between 30 and 40 million refugees, many of them, such as many Palestinians, living for decades outside their homelands. This is in addition to more than 40 million people displaced within their own countries.
While for a long time refugee numbers were reducing, in recent years, particularly driven by the Syrian conflict, there have been increases in the number of people being displaced.
During the COVID-19 crisis, boatloads of Rohingya refugees were turned away by port after port. This tragedy has echoes of pre-World War II when ships of Jewish refugees fleeing Nazi Germany were refused entry by multiple countries.
And as a catastrophe of a different kind looms, there is no international framework in place for responding to people who will be displaced by rising seas and other effects of climate change.
4. Conflicts without end
Across the world, there is a shopping list of unresolved civil conflicts and disputed territories.
Palestine and Kashmir are two of the longest-running failures of the UN to resolve disputed lands. More recent, ongoing conflicts include the civil wars in Syria and Yemen.
The common denominator of unresolved conflicts is either division among the great powers, or a lack of international interest due to the geopolitical stakes not being sufficiently high. For instance, the inaction during the Rwandan civil war in the 1990s was not due to a division among great powers, but rather a lack of political will to engage.
In Syria, by contrast, Russia and the US have opposing interests and back opposing sides: Russia backs the government of the Syrian dictator Bashar al-Assad, whereas the US does not.
5. Acting like it’s 1945
The UN is increasingly out of step with the reality of geopolitics today.
The permanent members of the Security Council reflect the division of power internationally at the end of World War II. The continuing exclusion of Germany, Japan, and rising powers such as India and Indonesia, reflects the failure to reflect the changing balance of power.
Also, bodies such as the IMF and the World Bank, which are part of the UN system, continue to be dominated by the West. In response, China has created potential rival institutions such as the Asian Infrastructure Investment Bank.
Western domination of UN institutions undermines their credibility. However, a more fundamental problem is that institutions designed in 1945 are a poor fit with the systemic global challenges – of which climate change is foremost – that we face today.