The minimum notice period required for a common citizen to approach the Court for an alleged offence under the Environment (Protection) Act, 1986, is 60 days.

Explanation:
The Environment (Protection) Act, 1986 is a significant legislation in India that aims to protect and improve the environment. It empowers the central government to take measures to prevent and control environmental pollution.

According to Section 19 of the Environment (Protection) Act, 1986, any person who believes that an offence under this Act has been committed can give notice of the alleged offence to the concerned authority. The concerned authority can be the central government, the State government, or any officer or authority appointed by the government.

The minimum notice period required for the alleged offence is 60 days. This means that the person who wishes to approach the Court must first serve a notice of the alleged offence to the concerned authority and wait for a period of 60 days before proceeding with the legal action. This notice period allows the concerned authority to take appropriate action or initiate legal proceedings, if necessary, to address the alleged offence.

During this notice period, the concerned authority may conduct an investigation, gather evidence, and take necessary steps to prevent further harm to the environment. It provides an opportunity for the authority to resolve the matter without resorting to legal proceedings if possible.

After the expiry of the 60-day notice period, if the concerned authority fails to take appropriate action or fails to resolve the matter, the person who served the notice can approach the Court to seek legal remedy for the alleged offence. The Court will then examine the evidence and decide whether the offence has been committed and what actions should be taken to address it.

In conclusion, the minimum notice period required for a common citizen to approach the Court for an alleged offence under the Environment (Protection) Act, 1986, is 60 days. This notice period allows the concerned authority to take necessary action and provides an opportunity for resolution before resorting to legal proceedings.