Caltrans revealed the demand Thursday from the main contractor, a joint venture called American Bridge/Fluor. Treacy delivered his estimate at a meeting in Oakland of the bridge project’s oversight panel, consisting of the heads of Caltrans, the state Transportation Commission and the local Metropolitan Transportation Commission. In September, it demanded $11 million from the joint venture for problems with high-strength steel rods on the bridge, including the failure of 32 of them on seismic-stabilizing structures in 2013. American Bridge/Fluor representatives have not commented about the project, but they have previously defended the quality of the joint venture’s work and said they would help Caltrans fix the tower rods problem. Construction delays and environmental protection efforts are contributing to the potential $140 million deficit on the bridge project, which has already cost $6.4 billion. Transportation officials have said there is enough money in toll-payer-financed funds to cover the repairs without having to bump up the cost of driving across Bay Area bridges. “We do have issues where there’s a lot of uncertainty about them,” said Treacy, referring to costs for environmental measures to protect nesting birds on the old span and reduce lead contamination in the bay as the structure is dismantled.