What is acid mine water and how can it be treated?

acid mine wateracid mine water
acid mine wateracid mine water


What is acid mine water and how can it be treated?

Mines use a large amount of water for their processes. And some of this water is negatively affected and can become toxic from some of the treatments that occur in mines. This is what is known as acid mine drainage and it has a dire effect on the environment. But luckily, it can be treated and this water can be cleared of the damaging chemicals from the mine by a mine water treatment plant.

There are many effective methods of acid mine drainage treatment in South Africa which use new mine water treatment technologies. They remove the heavy metals from the water and also ensure that the water is clean before it spreads out into the land surrounding the mine. If you are interested in mining wastewater treatment for your project, below is some helpful information on acid mine water and how to treat it.


What is acid mine water?

The first question you are likely to have is what is acid mine water exactly? Simple put, acid mine water or acid mine drainage (AMD) is formed when minerals which contain sulphite are exposed to water and oxygen. This means the water becomes acidic and is full of dissolved iron, which makes it unsuitable for returning to the environment.

As the pH levels of the water decrease, the mobilisation of other metals also happens, such as lead, copper, manganese, and even uranium. The impacted water is no longer suitable drinking water and can be damaging to the surrounding soil. Many mines are now striving to limit this from occurring in their mines, so they are looking into wastewater treatment technologies which treat the issue at the source.


How can it be treated?

There are several ways in which mines are treating their AMD issues, some of which are natural and others which involve using technology such as reverse osmosis and other recovery treatments. Others use more natural methods such as land reclamation and planting barriers around the mine to prevent the water from entering the surrounding environment.


Reclaiming contaminated land

Some mining companies reclaim contaminated land by using lime or other materials that are alkaline to neutralise the acidity of the water as well as adding uncontaminated topsoil and vegetation on the mining site. Some even heighten the slopes around the land to ensure that the runoff cannot easily infiltrate the soil.

This more natural method is popular as it is simply enhancing the surrounding environment and ensuring that the surface AMD water does not infiltrate the land in and around the mining site. It can be done before, during and even after the project is completed as a long term solution to AMD and its effect on the environment. Be sure that if you choose this method, you have permission from the municipality of the area.


Reverse osmosis

Reverse osmosis is used in the desalination of water, but it can also be used in treating acid mine drainage. It uses a double-pass mode in order to help with controlling scaling from calcium salts and metals. This method uses pH neutral conditions to remove any harmful acid-causing chemicals.

By using reverse osmosis, you can clean the water thoroughly and ensure that, should it reach the topsoil of the environment around the mine, it is not full of bad chemicals or heavy metals. Reverse osmosis is a highly effective method of treating acid mine drainage, but it is best performed by professional wastewater treatment companies. It is an efficient method to use and can also be cost-effective in the long run.


Filling in abandoned mines

Abandoned or disused mines are often one of the leading causes of acid mine drainage in South Africa. And in order to remedy this, we should be looking at filling in abandoned mines. But be sure that the materials used are not harmful to the environment and can be easily sourced from local vendors to save time, money and improve the local economy.

One method of filling in mines includes flooding the mine with water in order to remove the oxygen needed to form AMD.  Another method involves using alkaline materials to stop acid from forming in the water.  Ask for advice from a professional before moving ahead with this method, and be sure that the necessary authorities are aware that a mine is being refilled.



AMD is a serious consequence of mining and all mining companies should be actively working to prevent it from happening. You can use methods such as reclaiming the land and improving the vegetation surrounding t, or invest in reverse osmosis methods from a professional company. The filling in of disused mines is highly effective but should be done with care and with the help of experts.

acid mine water