Observation

This question was well attempted by the candidates and many of them scored
 high marks. 

The answers they gave included:

• mine collapse;
• flooding of mines;
• increase in geothermal gradient;
• poor ventilation;
• mine explosion;
• cave-in;
• release of poisonous gases;
• rock burst;
• water pollution;
• dust pollution;
• land degradation;
• noise pollution;
• ground vibration;
• destruction of vegetation.