Discuss the process through which the EU has changed environmental laws among its member states

The European Union (EU) has provided a comprehensive range of environmental legislation and regulation since its inception. Discuss the process through which the EU has changed environmental laws among its member states and the process and timeline equability (or not) of enactment across member states. Utilise appropriate and relevant examples of EU legislation spanning the last twenty years.

Citation and Referencing:
Harvard citation and bibliography structure.