PARIS (Reuters) - French nuclear group Areva AREVA.PA said on Friday that the head of its mining business, Sebastien de Montessus, resigned in a bid to close the chapter of the botched $2.5 billion takeover of Canadian start-up UraMin.
"He handed in his resignation to the board of directors which accepted it, in the interest of the group and to put an end to the trouble caused by the UraMin affair," an Areva spokeswoman said.
She made the comments after state-controlled Areva said in a statement Montessus had decided to leave the group and would be replaced by Olivier Wantz from March 31.
Wantz, who joined Areva in 2005, has been senior executive vice president, operations support, since June 2011.
The departure of Montessus follows his controversial role in the commissioning of at least one of two private investigation reports into the UraMin acquisition in 2007.
UraMin is at the center of a dispute between ousted Areva Chief Executive Anne Lauvergeon, known as "Atomic Anne," who oversaw the UraMin acquisition, and Areva, which has withheld Lauvergeon's 1.5 million euro severance pay.
Areva, the world's biggest nuclear reactor maker, bought UraMin to meet buoyant demand for uranium and as the price of the radioactive heavy metal peaked at $135 per pound.
Getting UraMin's three African mines to produce, however, proved to be tougher and costlier than expected.
Areva's new CEO Luc Oursel said in December he was writing down nearly their entire value, along with a wider group restructuring to reflect a slowdown in demand after March's nuclear disaster in Fukushima, Japan.
Lauvergeon, ousted by the French government in June, found in her mail late last year an anonymously sent report, dubbed Pomerol 4 and carried out by ALP Services in 2011, revealing her spouse Olivier Fric had been spied upon to see whether he had "illegally benefited" from the UraMin deal.
The discovery led to Lauvergeon filing a legal complaint with a Paris court against unidentified persons and the surfacing of another report written in 2010 by small French intelligence firm Apic, which suggested that UraMin may have been a scam.
Both reports, obtained by Reuters, were commissioned by Areva's security offices; but the later ALP one was under the responsibility of mining chief Montessus, who said in a newspaper interview that the "serious" conclusions of the Apic study led him to launch a counter-investigation.
Earlier this week, a parliamentary probe said that Areva had mishandled the UraMin acquisition, sharing the conclusion of an earlier internal company inquiry.
The parliamentary report's authors, like those of Areva's internal investigation, did not uncover any fraud, as some had feared, and did not make recommendations for how Areva could prevent the same mistakes from happening again.
Reporting By Muriel Boselli, Dominique Vidalon; Additional reporting by Caroline Jacobs; Editing by Gerald E. McCormick