The Maharashtra Pollution Control Board (MPCB) has issued a closure notice to a ready-mix concrete (RMC) plant at Mumbai's Mandale Metro project site for violating air pollution norms. This follows a previous notice issued to another Metro project RMC plant in BKC. The MPCB has intensified inspections across the city, issuing closure reports to four RMC plants and taking action against 37, collecting Rs 1.87 crore in fines. Investigations are ongoing to ensure compliance with norms like adequate tire washing and site covering.