Order of the National Green in the matter of Shibu Manuel, Secretary, Green Action Force Vs. The Govt. of India & Ors. dated 26/09/2018. The case relates to pollution being caused to the River Periyar in Kerala by discharge of effluents by more than 400 industrial units. As per the information received from the State Pollution Control Board, although the four most polluting industries have been identified, other industries also contribute to the pollution.