The manufacturing unit of the State-run National Aluminium Company Limited (NALCO) now faces a serious threat of being closed down on account of the company's inability to manage massive amounts of fly ash.

In a letter addressed to B.L. Bagra, NALCO's chairman-cum-MD, the State Pollution Control Board (SPCB) said it will be forced to close down its 1,200 mw-capacity Captive Power Plant, critical for running a smelter unit at Angul in Odisha, unless the company takes up the disposal of fly ash on a war footing.