Big Dig contractor settles for $50 million

BOSTON (AP) -- A concrete supplier for the Big Dig has agreed to pay $50 million to end civil and criminal investigations into whether it supplied inferior concrete used in the massive highway project, authorities announced Friday.

Aggregate Industries NE Inc. also agreed to plead guilty to a criminal charge of conspiracy to defraud the federal government.

Six employees of Aggregate, which supplied concrete used in tunnels and roadways in the Big Dig project, were indicted last year on federal charges that they falsified records to hide the substandard quality of 5,000 truckloads of concrete.

The company itself was not charged, but prosecutors at the time said their investigations were continuing.

The indictment charged the men with recycling concrete that was too old or already rejected by inspectors and in some cases double-billing for the loads. The company was paid $105 million for 135,000 truckloads of concrete, and at least 5,000 of those truckloads did not meet specifications, according to the indictment.

The settlement announced Friday will end the case against Aggregate, which is owned by Holcim, a concrete company based in Switzerland. The six employees await trials on charges of conspiracy to defraud the government, making false statements and mail fraud.

The deal with Aggregate does not affect a separate investigation by state Attorney General Martha Coakley and U.S. Attorney Michael Sullivan into the fatal tunnel ceiling collapse in July 2006. State and federal prosecutors have been negotiating with various Big Dig contractors to reach a settlement in that case.