SAO PAULO, Oct 7 (Reuters) - A commission hired by Brazil's state-run energy utility Eletrobras to probe possible violations of U.S. and Brazilian anti-corruption laws involving the company is studying three Amazonian dam projects and a nuclear power plant, two sources familiar with the investigation said.
They said the commission is investigating possible bribery in two $5 billion dam projects on the Madeira river, Santo Antonio and Jirau, as well as the massive Belo Monte dam and the Angra 3 nuclear power plant that prosecutors have already linked to a huge corruption scandal.
Both sources said the investigation is at an early stage but that the commission is looking at everything from how construction contracts on the projects were awarded to heavy cost overruns. Eletrobras owns Angra 3 through its Eletronuclear subsidiary and has a stake in the three dams under review.
One of the sources said the commission is sharing its information with the U.S. Department of Justice and the U.S. Securities and Exchange Commission.
Both the SEC and DOJ declined to comment when asked if they were investigating Eletrobras. Eletrobras said it would only comment on the commission's probe when it was concluded.
Brazilian federal prosecutors say construction firms involved in Brazil's largest-ever corruption scandal at state oil company Petrobras likely repeated a price fixing and political kickback scheme at Eletrobras, a smaller state-run firm that employs some of the same contractors as the oil giant.
Any discovery of corruption could force a balance sheet write-off and delay completion of the dams, preventing them from reaching their full capacities at a time Brazil's energy grid is recovering from drought.
Eletrobras, formally known as Centrais Eletricas Brasileiras SA, hired U.S.-based law firm Hogan Lovells in June to assess possible graft involving Eletrobras and private construction firms but did not say which projects were being checked.
It later appointed Brazilian firms WFaria Advogados and R. Amaral to evaluate any violations of Brazilian law, as well as three independent commissioners, the sources said.
The commission aims to complete its review this year and may recommend a write-off, one source said. Petrobras wrote off $2 billion in graft losses in April.
Brazil's Federal Accounts Court, the TCU, says it is also concerned about possible corruption on Eletrobras dam projects in which private contractors under investigation have a stake or were hired to do work.
The dams have less oversight than the Petrobras contracts and their projected construction costs have more than doubled, according to TCU investigator Sergio Caribe, who is leading a review initially focused on Belo Monte.
"Over-pricing is an indication that something is not right," he said in an interview.
Representatives for Santo Antonio operating consortium Santo Antonio Energia and the Belo Monte operating consortium Norte Energia said they had not been informed of any irregularities found by the commission.
The consortium operating Jirau, Energia Sustentavel do Brasil (ESBR), attributed the rising costs to inflation, an expansion of the project and damages from two fires. It said the dam should not have been included in Eletrobras' internal investigation.
Santo Antonio Energia said its additional investments were all normal and had been approved by shareholders.
Petroleo Brasileiro SA, as Petrobras is formally known, has been investigated by the SEC and the U.S. Department of Justice since last year.
Both Petrobras and Eletrobras have shares on the New York Stock Exchange and are subject to the U.S. Foreign Corrupt Practices Act, which aims to prevent graft by companies linked to the United States.
Brazilian prosecutors this month charged Othon Luiz Pinheiro da Silva, the chief executive of Eletronuclear, with corruption and money laundering. He is accused of taking 4.5 million reais ($1.1 million) in bribes related to the Angra 3 plant near Rio de Janeiro.
The Santo Antonio dam, Brazil's fourth largest, includes participation from Eletrobras subsidiary Furnas, Caixa FIP Amazonia Energia, SAAG Investimentos and Cemig Geração e Transmissão.
Odebrecht Energia, part of Latin America's largest engineering group Odebrecht SA, has an 18.6 percent stake in Santo Antonio and was also hired to build it. Odebrecht declined to comment.
Jirau is a venture by France's Engie SA, formerly known as GDF Suez, as well as Japan's Mitsui & Co, and Eletrobras subsidiaries Eletrosul and CHESF. The other stakeholders referred questions to the ESBR consortium.
Camargo Correa had an operating stake in Jirau and was building it, though it sold its shares to GDF Suez in 2012 and is no longer involved. ESBR said dozens of construction companies have been hired.
Camargo Correa did not respond to request for comment.
($1 = 4 reais)
See graphic on Petrobras and Eletrobras corruption scheme reut.rs/1GQrMVf (Additional reporting by Mica Rosenberg in New York, Anthony Boadle in Brasilia, Sarah Lynch and Joel Schectman in Washington; Editing by Kieran Murray)