A U.S. senator wants Braidy Industries CEO Craig Bouchard to explain how a controversial Russian company that used to be under federal sanctions ended up investing in the aluminum rolling mill that Bouchard's company plans to build near Ashland, Kentucky.

U.S. Sen. Ron Wyden, a Democrat from Oregon, sent Bouchard a letter Tuesday with a series of questions about what preceded United Co. Rusal's declaration that it would invest $200 million in return for a 40% stake in the roughly $1.7 billion mill.

Rusal is partly owned by Oleg Deripaska, a Russian oligarch. American sanctions on Rusal and its parent company, En+ Group, were lifted earlier this year.

Then, in April, the Russian aluminum company's new partnership with Braidy was announced.

The following month, Wyden and seven other congressional Democrats — including U.S. Rep. Adam Schiff, who is a key player in the House of Representatives' impeachment inquiry into President Donald Trump — sent Treasury Secretary Steven Mnuchin a letter requesting a federal review of Rusal's deal with Braidy.

The investment "raises serious questions of national security," the Democrats wrote.

Earlier:Kentucky Supreme Court clears way for release of names of Braidy investors

Wyden, the ranking member of the Senate Finance Committee, apparently hasn't forgotten about Braidy in the intervening months. His letter this week to Bouchard seeks further information about the company's dealings with Rusal.

In a company statement Wednesday, Braidy said Wyden will receive a response to his inquiry.

Wyden noted that a story published by Time magazine included statements Bouchard made about a dinner he had in Zurich with a sales executive from Rusal in January 2019, when the company was still under sanctions.

The Time article quoted Bouchard as saying the Rusal executive suggested they meet again if the sanctions were lifted.

In his letter to Bouchard, Wyden asks the CEO to identify the person he met with from Rusal that day and provide other details on the meeting, including how it was arranged and who paid for it.

"Was a potential investment by Rusal in Braidy Atlas discussed during this dinner, or at any other time prior to sanctions being lifted?" Wyden wrote to Bouchard.

Braidy Atlas is a subsidiary of Braidy Industries that's handling the aluminum mill project.

Likewise, Wyden asked whether the potential for a 10-year agreement under which an affiliate of Rusal plans to supply aluminum for Braidy's mill — a deal that has since been announced by the companies — came up during the dinner.

Wyden also cited a Jan. 4 article in The Courier Journal about Braidy's monthslong effort to secure financing for the mill's construction, which stated that Braidy had recently said there was more than $1 billion in "substantial indications of interest" from investors.

"At the time of this statement, had Braidy had any discussions with Rusal about investing in Braidy Atlas?" Wyden asked Bouchard in the letter.

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Wyden also quoted from a 2009 book Bouchard co-wrote called "America for Sale: How the Foreign Pack Circled and Devoured Esmark," in which Bouchard recounted how a steel business that he once helped lead ultimately was sold to a Russian company in 2008.

In that book, Bouchard and co-author James Koch wrote: "It is not comforting to know that Russia's Vladimir Putin might be lurking in the background, calling signals for the Russian oligarchs. … If Prime Minister Putin harbors a nasty wish to throw a wrench into the works of the U.S. economy, then he now has acquired the means to do so because of significant Russian ownership within the U.S. steel industry."

In his letter, Wyden asks Bouchard if he believes the ownership interests Deripaska and VTB Bank — which is owned by the Russian government — have in Rusal might enable Putin to someday "throw a wrench into the works of the U.S. economy?"

Other questions Wyden sent Bouchard include:

Was Bouchard's January 2019 meeting with a Rusal sales executive, or any other discussions with the Russian company's representatives, disclosed to anyone in the state or federal government before the sanctions were lifted?

Did Bouchard or any representative of Braidy discuss their business interests with Deripaska at any time?

Does he know if the Russian Direct Investment Fund — a Russian sovereign wealth fund that previously invested in Rusal's parent company — currently has an ownership interest in that business or in Rusal?

If so, what safeguards are in place to prevent the Russian sovereign wealth fund from accumulating "political and economic muscle" over the U.S. aluminum industry through its affiliation with Rusal?

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Braidy provided the following company statement to The Courier Journal on Wednesday afternoon.

"In full transparency, we previously made the facts widely known concerning Rusal’s direct minority investment in the greenfield Braidy Atlas aluminum rolling mill, including on our website," Braidy said. "This investment and the supply contract allow Braidy Atlas to create the most sustainable aluminum production in the world for the automotive and food and beverage industries, creating 600 permanent jobs, $2.8 billion of economic impact for the Commonwealth of Kentucky, and over $390 million of combined economic uplift for the neighboring states of Ohio and West Virginia.

"Our CEO, Craig Bouchard, spoke before the United Nations Global Climate Action Summit in New York last week. Braidy Atlas has taken a leadership role in the international coalition to bring the aluminum industry to zero net carbon emissions by 2050. The health and prosperity of our community are of a higher priority than political partisanship.

"We look forward to providing Sen. Wyden with a timely response to his inquiry and interest in our example of leadership in the economic revitalization of Appalachia."

Wyden has asked Bouchard to respond to the questions he sent by Nov. 1.

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Morgan Watkins: 502-582-4502; mwatkins@courierjournal.com; Twitter: @morganwatkins26. Support strong local journalism by subscribing today: courier-journal.com/morganw.