Effluent is liquid waste or sewage discharged into a river or the sea.

The firm has made a written representation to CPCB to cancel the order, but company officials said it would not have any material impact as the plant is already under planned shutdown between February 21 and April 15 for relocation of ammonia pipeline and maintenance.

CPCB order was based on an analysis of sample drawn on January 9, which is said to have breached the norms for discharge of effluents, the company said.

"The company in its representation (to CPCB) has submitted reports of parallel samples drawn on the same day as CPCB, confirming compliance with norms by the State Pollution Control Board-approved lab," the company said.

The plant produces fertiliser like diammonium phosphate and single superphosphate.