Most of the offences were committed in Assam, while there are instances of flouting norms in other states like Tripura, Meghalaya and Sikkim, Environment Minister Jayanthi Natarajan said during the Question Hour.
She said the number of offences in 2011 was 10. It was higher at 11 in 2010 and 13 in 2009. Apart from the oil PSUs, companies such as Assam Roofing, North Eastern Electric Power Corporation, Meghalaya Energy Corporation and Amrit Cement Industries among others flouted the norms.
To a separate question, Natarajan said the proposal to establish a National Environment Assessment and Monitoring Authority (NEAMA) in north-east has not yet been finalised.
NEAMA was proposed to set up to strengthen and professionalise the regimes of environment impact assessment and coastal zone management.