After the group began digging in the Pacific zone of the canal, the basalt they found there was not right for the mix of concrete they planned for the locks, so they had to bring in basalt from elsewhere, resulting in higher costs, said Jose Pelaez, head of the GUPC section building the Atlantic locks.
Earlier this week, the consortium led by Spanish builder Sacyr said the scheme to build a third set of locks for the canal had incurred additional costs of $1.6 billion, and demanded Panama foot the bill or work would be suspended.
The consortium known as Grupo Unidos por el Canal (GUPC), told reporters that when excavations to build the locks began, they found the geology of the area was more complex than had been made clear when the project was tendered.