AMD & Heavy Metal Pollution (p1) Flashcards
(23 cards)
What is Acid Mine Drainage (AMD)?
Drainage waters from coal and metal mines containing oxidised ores such as pyrites, leading to acidic water and dissolved metals.
What is the primary cause of Acid Mine Drainage?
Oxidation of sulfide ores when in contact with air, forming sulfuric acid.
What are the environmental effects of Acid Mine Drainage?
- Direct harm to living organisms
- Indirect harm by mobilising toxic heavy metals
What are the two types of treatment for Acid Mine Drainage?
- Active treatment
- Passive treatment
What is involved in the Active Treatment of Acid Mine Drainage?
- Settlement of mine-water
- Precipitation of metal hydroxides
- Flocculation and coagulation of precipitated metals
What is passive treatment for Acid Mine Drainage?
Using natural biological processes and sustainable methods to manage drainage.
What is Bioaccumulation?
The build-up of heavy metals in living organisms due to ingestion.
What is Biomagnification?
The increase of heavy metal concentration along the food chain.
How do heavy metals cause harm?
Heavy metals can cause harm by inhibiting enzymes, particularly affecting the nervous system.
What is the effect of heavy metals at low pH?
Most heavy metals are more soluble at lower pH, increasing their mobility.
What are common sources of lead pollution?
- Paint pigments
- Pipework
- Batteries
- Tetraethyl lead in petrol
- Fishing weights
- Lead shot from shotgun cartridges
What are the general effects of lead on living organisms?
- Anaemia
- Headaches
- Learning disabilities
- Impaired nervous system development
- Delayed growth
What measures can be taken to control lead pollution?
- Replace lead pipes with copper or plastic
- Remove lead from petrol
- Use lead-free solder
- Remove lead-based paint
What are the toxic effects of mercury?
- Insanity
- Birth defects
- Nerve disorders
- Death
What are common sources of mercury pollution?
- Disposal of batteries and fluorescent lights
- Combustion of coal
- Chemical plants using mercury electrodes
What is cadmium and its main sources?
- Nickel-cadmium batteries
- Incineration of cadmium-containing waste
- Drainage from cadmium mines
What are the effects of cadmium exposure?
- Brain damage
- Lung cancer
- Kidney failure
- Skeletal collapse
What is Tri-butyl tin (TBT) and its effects?
A compound found in marine paints that disrupts growth and reproduction in marine organisms.
What is the environmental impact of iron in water?
Iron can cause deoxygenation, leading to the death of aerobic organisms.
Fill in the blank: The process of using limestone to neutralise acidity in passive treatment is called _______.
[phytoremediation]
True or False: Heavy metals are beneficial for physiological processes in high concentrations.
False
What is the significance of the Zamfara State case study?
Lead poisoning from illegal gold extraction resulted in numerous deaths and highlighted contamination issues.
What is the role of microorganisms in passive treatment of Acid Mine Drainage?
They help break down metal compounds and contribute to the precipitation of metals.
