Where is acid mine drainage located?
Where is acid mine drainage located?
Acid mine drainage can be released anywhere on the mine where sulfides are exposed to air and water — including waste rock piles, tailings, open pits, underground tunnels, and leach pads.
What acid is most commonly found in mine drainage?
sulfuric acid
Mine drainage is formed when pyrite (an iron sulfide) is exposed and reacts with air and water to form sulfuric acid and dissolved iron. Some or all of this iron can precipitate to form the red, orange, or yellow sediments in the bottom of streams containing mine drainage.
What is the three major sources of acid mine drainage?
This introduction of water is the initial step in most acid rock drainage situations. Tailings piles or ponds, mine waste rock dumps, and coal spoils are also an important source of acid mine drainage.
Which mines cause acid mine drainage?
The major culprits are the coal and gold mines, and because of their location in the upper portions of the Vaal River catchment, their footprint on the water supply is huge. Aside from metal and acid pollution, the major problem is the increase in dissolved salts into the Vaal River.
How long will Acid Mine Drainage continue?
Acid mine drainage and metal leaching are a particular concern because they can continue indefinitely, causing environmental damage long after the mine operation has ended. 2 Acid mine drainage still occurs from hard-rock mines in Europe that were worked by ancient Romans prior to A.D. 476.
What mining companies can solve the problem of acid mine drainage?
The most prevalent method for treating AMD contamination is the addition of alkaline reagents such as lime, limestone, sodium carbonate or sodium hydroxide. This treatment aims at neutralizing acidic water and the precipitation of heavy metals.
How do you prevent acid rock drainage?
Some common methods include: Reclamation of contaminated land by (1) adding lime or other alkaline materials to neutralize the acidity, and (2) adding uncontaminated top soil, planting vegetation, and modifying slopes to stabilize the soil and reduce infiltration of surface water into underlying contaminated material.
How do you stop acid rock drainage?
To treat ongoing problems, usually from abandoned mines, companies can add lime (a very basic chemical that lowers the acidity), divert the runoff through limestone channels for the same effect, or even use constructed wetlands to treat the water before it reenters existing watercourses.
How do you counteract acid mine drainage?
How can preventing acid mine drainage save water?
The most effective method to minimize penetration of air and water through the waste pile is to use a cover, either wet (water) or dry (soil) which is placed over the waste pile. Despite their high cost, these covers cannot always completely stop the oxidation process and generation of AMD.
Why there are so many mine dumps in South Africa?
The prevalence of mine dumps across the landscape in many parts of the country is a reminder that the mining industry is an integral part of the South African economy. Mine dumps are not merely waste material or the remnants of mining operations. Valuable mineral deposits may remain in these dumps.
What would you recommend for treating acid mine drainage?
What is acid mine drainage (AMD)?
Sulphur, in the form of sulphates and sulphuric acid which drain from sulphide rich ores once they’re exposed to surface environments. This sulphuric run-off from mining is often referred to as acid mine drainage (AMD). AMD was described as the largest environmental problem facing the U.S. mining industry.
How does acid mine drainage affect the environment in the UK?
In the coal belt around the south Wales valleys in the UK highly acidic nickel-rich discharges from coal stocking sites have proved to be particularly troublesome. Acid mine drainage also affects the wildlife living within the affected body of water.
How did acid rock drainage affect the construction of I 99?
Acid rock drainage was a hindrance to the completion of the construction of Interstate 99 near State College, Pennsylvania. However, this acid rock drainage didn’t come from a mine; rather, it was produced by oxidation of pyrite-rich rock which was unearthed during a road cut and then used as filler material in the I-99 construction.
How does acid rock mining affect the water table?
Sub-surface mining often progresses below the water table, so water must be constantly pumped out of the mine in order to prevent flooding. When a mine is abandoned, the pumping ceases, and water floods the mine. This introduction of water is the initial step in most acid rock drainage situations.
