How do you identify acid mine drainage?
Acid drainage is often marked by “yellow boy,” an orange-yellow substance (visible in the photo on this page) that occurs when the pH of acidic mine-influenced water raises above pH 3 (approaching more neutral conditions), so that the previously dissolved iron precipitates out.
What is ARD mining?
THE MINING INDUSTRY Acid rock drainage (ARD), also referred to as acid mine drainage (AMD), is the outflow of acidic water from mining operations including waste rock, tailings, and exposed surfaces in open pits and underground workings.
What are the main indicators of acid mine drainage?
Both sulfate and conductivity are useful indicators of acid mine drainage (AMD) contamination. Unlike pH, they are both extremely sensitive to AMD even where large dilutions have occurred.
What are the effects of acid rock drainage?
Problems associated with mine drainage include contaminated drinking water, disrupted growth and reproduction of aquatic plants and animals, and the corroding effects of the acid on parts of infrastructures such as bridges.
How do you treat 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.
What is the difference between acid rock drainage and acid mine drainage?
In some cases acid rock drainage is a natural phenomenon. Some misleading call it acid mine drainage as if it’s exclusive to mining but acid rock drainage only occurs where there are sulfide minerals and many mines excavate rocks that do not even contain these minerals.
How is acid mine drainage treated?
What does acid mine drainage smell like?
When exposed to oxygen and water, pyrite forms yellow and white salts of iron sulfate and sulfuric acid. As these rocks are flushed by rainfall or snowmelt, the salts and acids are released in the water and enter the streams. Another way to tell if a stream is impacted by AMD is if the water has a rotten egg smell.
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.
How long will acid mine drainage continue?
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 long will Acid Mine Drainage last?
At some mines, acidic drainage is detected within 2–5 years after mining begins, whereas at other mines, it is not detected for several decades. In addition, acidic drainage may be generated for decades or centuries after it is first detected.
What kind of testing is acid rock drainage?
Acid Rock Drainage Testing. Subject. Acid rock drainage (ARD) is the outflow of acidic water from mining operations including waste rock, tailings, and exposed surfaces in open pits and underground workings. SGS laboratories offer complete ARD testing services that help predict acidic effl uents.
How does acid rock drainage ( ARD ) work?
Acid rock drainage (ARD), also referred to as acid mine drainage (AMD), is the outflow of acidic water from mining operations including waste rock, tailings, and exposed surfaces in open pits and underground workings. ARD forms as a result of the dissolution of sulphides, mainly pyrite (FeS.
What kind of tests are used to diagnose dyslexia?
Here’s a selection of 14 tests, and their respective strengths, that we recommend using with dyslexics. Given that reading disability and dyslexia have an underlying language component, language testing is essential when making a diagnosis.
Why do kids like the dyslexia battery test?
It is a standard test in our battery. It is fun to give and kids like taking it because it is almost like a game. You can compare and contrast the subtests to determine whether the student has difficulty with phonological analysis versus synthesis (or both).