Problems of Mining and Making It Sustainable

35 min

Let's begin

Kolmanskop, in the Namib Desert of Namibia, was once a busy diamond town with a hospital, a school and a ballroom. When the diamonds nearby ran out and richer deposits were found further south, the people left. Today sand drifts through the empty houses, and tourists pay to walk through them. Every mine ends one day. What damage can mining do while it lasts, and how can a country make sure that something good remains when the minerals are gone?

Problems of mining

Type	Problem	Example or explanation
Environmental	Land degradation	Pits, spoil heaps and tailings cover farmland and forest, as around the Copperbelt mines of Zambia
	Water pollution	Acid water and chemicals drain from mines; mercury and mud from illegal gold mining (galamsey) have turned rivers brown in Ghana
	Air pollution	Dust from blasting and roads; sulphur dioxide from smelters; gas flaring in the Niger Delta
	Oil spills	Leaking pipelines have polluted creeks, farms and fishing grounds in the Niger Delta
Social and health	Accidents and disease	Rock falls, flooding and explosions underground; lung diseases from rock dust
	Child labour and unsafe artisanal mines	Children work in some small mines in DR Congo and elsewhere
	Conflict	Diamonds paid for weapons in Sierra Leone's civil war (1991–2002); armed groups have profited from minerals in eastern DR Congo
Economic	Changing world prices	When copper prices fell in the 1970s and 1980s, Zambia's income collapsed
	Exhaustion of deposits	Ghost towns such as Kolmanskop when the ore runs out
	High costs and foreign control	Capital, machines and experts come from abroad, and much of the profit leaves the country
	Smuggling and little processing	Lost taxes; raw ores exported without adding value

Definition

Tailings: the finely ground waste left after the valuable mineral has been removed from the ore, often stored behind dams. Spoil heap: a heap of waste rock and overburden from a mine. Rehabilitation: restoring mined land so it can be used again, by filling pits, replacing topsoil and planting. Environmental Impact Assessment (EIA): a study made before a project starts, to predict its effects on the environment and people and plan how to reduce them.

Making mining sustainable

Sustainable mining means taking minerals in a way that limits harm while the mine works, shares the benefits fairly, and leaves the land usable afterwards. Figure 3 shows the life cycle that good mining follows: the closing and rehabilitation of the mine are planned from the very start.

Plan before digging: an EIA and consultation with local people before a licence is given.
Control pollution: line tailings dams, treat waste water, damp down dust, and replace mercury in gold processing.
Rehabilitate the land: refill pits, put back the topsoil and plant trees and grass on spoil heaps.
Protect workers: safety rules, helmets, boots and dust masks, training and inspections; no child labour.
Organise small miners: licence artisanal miners and group them into cooperatives that can get training, equipment and fair prices.
Trace the minerals: certify where minerals come from, so that buyers avoid conflict minerals. The Kimberley Process (from 2003) certifies rough diamonds; bags of tin, tantalum and tungsten ore can be tagged at the mine, as in the iTSCi scheme used in the Great Lakes region.
Add value and save for the future: process ores at home, and invest mining income in education, roads and other industries before the ore runs out.

Rwanda's mining board (RMB) links the rise in mineral export earnings in 2023 to more value addition, more professional operations, greater investment in machines, and sustainable and responsible mining practices.

Worked example

Worked example 1: how long will a deposit last? (illustrative figures) A mine has proven reserves of 36 million tonnes of ore and processes 1.8 million tonnes a year. How many years will it last at this rate?

Life of mine = reserves ÷ yearly output = 36 ÷ 1.8 = 20 years.
Conclusion: the town that grows around the mine has about twenty years to build other sources of jobs and income.

Worked example

Worked example 2: paying for rehabilitation (illustrative figures). A company must set aside 4% of its yearly sales of 50 million US dollars for closing and rehabilitating the mine. How much does it save in a year, and in 20 years?

One year: 4% × 50 = 0.04 × 50 = 2 million US dollars.
Twenty years: 2 × 20 = 40 million US dollars.
Conclusion: saving from the start means money is ready to repair the land when the mine closes.

Warning

Don't stop at "mining causes pollution". Say what is polluted, by what, and with what effect: "Mercury used by small-scale gold miners washes into rivers, poisoning fish and the people who drink the water." Precise chains earn the marks.

Tip

Sort mining problems into three columns, environmental, social and economic, and match each one with a solution in a fourth column. The table above is your model.

Rwanda Mines, Petroleum and Gas Board: how Rwanda's mining sector protects the environment, from managing waste to planting trees. List three practices shown.

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Practice

Define tailings and rehabilitation.
Give three environmental problems caused by mining, with an African example of each.
Explain why mining towns can become ghost towns, using Kolmanskop as an example.
How did diamonds make the civil war in Sierra Leone worse, and what was done about it?
Describe four ways to make small-scale mining safer and cleaner.
A mine holds 24 million tonnes of ore and processes 1.5 million tonnes a year. Calculate its life in years.
Use Figure 3 to explain why rehabilitation should be planned before mining begins.
"The benefits of mining in Africa are greater than its costs." Discuss.

Show answersHide answers

Tailings: finely ground waste left after the mineral has been removed from the ore. Rehabilitation: restoring mined land so it can be used again.
Any three: land degradation by pits and spoil heaps (Copperbelt); water pollution by mercury and mud (galamsey in Ghana); air pollution by dust, smelter fumes and gas flaring (Niger Delta); oil spills (Niger Delta); deforestation.
Towns grow only because of the mine; when the ore runs out or a richer deposit is found elsewhere, jobs disappear and people leave, as at Kolmanskop when its diamonds ran out.
Armed groups sold diamonds to buy weapons, prolonging the war (1991–2002). The Kimberley Process (2003) now certifies rough diamonds so that buyers can avoid conflict diamonds.
Any four: licensing; cooperatives; training; helmets, boots and masks; supported shafts; no child labour; replacing mercury; refilling pits; tagging and tracing the ore.
24 ÷ 1.5 = 16 years.
Closing and rehabilitating cost money and need planning; if they are planned at the assessment stage, the company saves for them, keeps the topsoil, and leaves land that can be used again instead of an abandoned pit.
Benefits: jobs, export income, taxes, infrastructure (Botswana, Rwanda). Costs: pollution, accidents, conflict, price shocks, exhaustion. A judgement: the benefits outweigh the costs only where governments control pollution, share revenues fairly and invest in other sectors.

Sources and credits

Environmental impact of mining, Kolmanskop, Kimberley Process Certification Scheme, Blood diamond and Galamsey: Wikipedia contributors, Wikipedia, CC BY-SA 4.0, adapted by Ganzaa.
Rwanda Mines, Petroleum and Gas Board (RMB), Rwanda's Mineral Export Earnings Surge in 2023 (15 February 2024): reasons given for the growth in mineral exports. Facts used as stated.
Photo: Kolmanskop (19111850769), David Stanley, Wikimedia Commons, CC BY 2.0.
Photo: Zambia 4 (Nchanga copper mine), BlueSalo, Wikimedia Commons, CC BY-SA 3.0.
Video: Mining and environmental protection, Rwanda Mines, Petroleum and Gas Board (RMB), embedded from YouTube.
Figure 3, tables, worked examples and exercises: written by Ganzaa.

This lesson adapts CC BY-SA material and is shared under CC BY-SA 4.0.

1Problems of mining

2Making mining sustainable

Problems of mining

Making mining sustainable