The couple accused in the killing of 30,000 fish in the Rocky River in April were set to be arraigned Thursday, but only one entered a plea. 

Teresina Montorsi, 74, pleaded not guilty in U.S. District Court and was released on $25,000 unsecured bond, according to Mike Tobin, spokesman for the U.S. Department of Justice.

Renato Montorsi's lawyer asked for a competency hearing, so that is being scheduled following medical exams, Tobin said.

Renato Montorsi, 79, is accused of draining a barrel of liquid cyanide into a storm sewer near his Strongsville business. The toxin allegedly flowed into the Rocky River and killed some 30,000 fish along a 3-mile stretch, from around Bonnie Park in Strongsville through Berea and Middleburg Heights.

The couple have been indicted on charges of conspiracy and obstruction of justice. Renato Montorsi also is accused of violating the Clean Water Act.

Montorsi owns Kennedy Mint Inc., a collectible coin business at 12102 Pearl Rd. in Strongsville, but previously conducted metal plating and printing operations at the location, the indictment says. 

The East Branch of the Rocky River is near the Kennedy Mint facility and storm water from that location’s parking lot flows into the East Branch of the Rocky River, according to the indictment.

U.S. Attorney Steven Dettelbach has said Renato Montorsi tried to dispose of a 55-gallon drum of cyanide in a municipal trash receptacle, but the garbage collectors refused to take the barrel, which was marked as a hazardous chemical. 

Federal law requires special disposal of hazardous chemicals.

Instead, Dettelbach said Montorsi "figured out his own way of disposing of the chemical" -- he rolled the drum to a storm sewer, used a spike to punch a hole in the side and let it drain into the sewer.

The sewer carried the liquid poison to the Rocky River.

Teresina Montorsi allegedly participated in the cover-up by helping hide the barrel. The couple lives in Grafton.