A fish processing plant has been given 30 days to stop rotten odors or face having to close down until the problem can be solved, thetelegraph.com reported.

American Heartland Fish Products processes Asian carp at a rendering plant in Grafton, Illinois, but has faced strong criticism over the smell coming out of the facility.

Now, it could be fined or shut down unless the nuisance odor is abated within the next month.

City attorney Jim Schrempf, speaking at an appeal hearing last week, said: "The city welcomed the new manufacturing business to Grafton, believed what they said that there'd be no adverse effects and in fact beneficial in eliminating Asian carp. But it causes unacceptable odor and the equipment is not as good as the makers of the equipment claimed."

American Heartland has a limited time to appeal against the written order that was filed by Grafton Police Chief Chris Sullivan after the appeal hearing concluded.

The facility, which opened in April, processes about 60,000 pounds of Asian carp a day, turning the invasive species into fish oil, fish meal and bone meal. American Heartland has invested about $3 million in the plant.

Earlier this month the Illinois Environmental Protection Agency visited the plant and recommended that engineers increase the height of exhaust stacks. That recommendation has been followed but not yet tested.