A volcano is an opening in a planet crust through which molten rock and gases trapped under the surface erupt, often forming a hill or mountain.

Impacts

Primary

• Molten lava destroys everything in the path(Lava flows)
• Fast moving avalanche of volcanic material(Pyroclastic flow)

Secondary

• Landslides
• Tsunamis
• Flooding

Mitigation Strategies

• Monitoring and eruption prediction
  • Exclusion zones of places high risk for eruptions
• Evacuation polices
  • Plans
  • Shelters with food and water
• Hazard assessment
  • Hazard maps
• Awareness
  • Make people aware of the risks of volcanos and the plan of action
• Lava flows
  • Cooling with water
  • Construction of diversions and barriers
  • Channels
• Pyroclastic flows
  • Only good method of mitigating the effects of pyroclastic flow is to evacuate people, due to the sheer power of it.