(Recasts with internal plans to focus on efficiency)
By Susan Taylor
TORONTO, Oct 29 (Reuters) - Barrick Gold will increase its focus on productivity and efficiency gains in 2016 to further improve its balance sheet, the world's biggest gold producer said on Thursday.
Barrick, which has the highest debt of any gold miner, began 2015 with a $13.1 billion in debt, which it had whittled to $11.2 billion as of Wednesday.
The Toronto-based company plans to put about $1 billion from the sale of its Zaldivar copper mine toward debt, with free cash flow used to reach its $3 billion debt reduction target for 2015.
And there are no plans to ease off, Barrick told analysts on Thursday.
"We've actually got internal plans which are focusing more intensely, as we go forward, on productivity and efficiency," said Chief Financial Officer Shaun Usmar on a conference call.
Each mine is now being scrutinized for ways to improve operations by boosting revenue, for example, or cutting costs.
"That will be the next incarnation, because there is opportunity. You've seen the sector, as a whole I think, see deteriorating productivities for a fairly long period of time and that's the next frontier we seek to address," Usmar said.
The company also said it has just begun a second round in the sales process for six U.S. gold assets that it wants to divest and expects to sign at least one agreement before year-end.
"It's a very competitive, robust process," said senior vice-president Kevin Thomson on the call. "Our expectation is to sign one or more binding agreements before the end of the year."
Barrick has said it will sell six of its U.S. gold mines and projects: Bald Mountain, Round Mountain, Spring Valley, Ruby Hill, Hilltop and Golden Sunlight. (Reporting by Susan Taylor; Editing by Bernadette Baum and Cynthia Osterman)