Rival gold mining magnates pointed fingers at each other Thursday in the wake of the catastrophic spill that is fouling waterways in the southwest. 

The owner of the Gold King Mine, which the Environmental Protection Agency identified as the source of last week's spill, told the Denver Post that backed up waste water from nearby Sunnyside Mine was the real cause.

"It is our belief that, when Sunnyside [Gold Corp.] put bulkheads inside the Sunnyside Mine, they redistributed the flow of wastewater out of other mine portals,” Todd Hennis  told the newspaper, claiming that the two mines are among four in the area which are all connected by underground tunnels. “It is a bad flow, very high in the nasty minerals, very acidic.”

Hennis called for Sunnyside parent company Kinross, a $2.3 billion international mining firm, to voluntarily install a water-treatment plant for $5 million to $20 million on nearby Cement Creek to prevent further harm to the Animas and downriver communities.

"Please, Kinross, step up," Hennis said. "Do a voluntary deal with the EPA. You need to set up a treatment plant to deal with the water impacts of the bulkheads inside the Sunnyside Mine."

Hennis, who also owns nearby Mogul Mine, pledged total cooperation with the EPA on the cleanup from the Gold King spill.

Officials for Kinross said their mine had nothing to do with the incident.

“The water discharge at Gold King mine on Aug. 5, 2015 was very unfortunate and EPA Administrator Gina McCarthy has stated that the ‘EPA does take full responsibility for this incident,’” read a statement provided to FoxNews.com from Kinross. “Sunnyside Gold Corporation is not involved whatsoever; it never owned or operated Gold King and did not take part in work being done there. Sunnyside mine workings have no physical connection to the Gold King and such a connection never existed. Sunnyside is not the cause of the water buildup at Gold King.”

Hennis told the Denver Post Kinross is being dishonest.

"They are lying. They leased the Gold King extension in 1989,” Hennis said. “They mined it in 1990 from Sunnyside — and then left everything open. The bulkheads at Sunnyside caused mine pools that extend into Gold King."

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