pollution

• Unconfined aquifers are easier to pollute due to it being open to the atmosphere. They tend to have springs that are more polluted after discharge, leading to the contamination of rivers. 
• A confined aquifer is harder to pollute due to the lack of exposure to the atmosphere at recharge zones, often in upland areas with few pollutants. True confined aquifers have no springs so are unable to discharge contaminated water. 
• Small levels of pollution from acid mine drainage due to solution from underground ore bodies. Ores from mined gangue minerals are left in spoil heaps, when in contact with any oxygenated water any sulphide minerals react to make sulphuric acid. 

  • This reduces the pH of water 
  • Acidic water dissolves elements like lead 
  • Polluted water makes its way into groundwater 

   

   
• Leaks of hydrocarbons, pesticides and fertilisers, sewage and leachate from landfill.