Workers at the Richards Bay Coal Terminal in South Africa rejected its latest wage offer and will continue to strike, according to the main labor union at the port.

Members of the Association of Mineworkers and Construction Union lowered their demand to a one-year 7% basic salary increase and a housing allowance, said Bheki Sithole, the union’s regional secretary. RBCT, the biggest coal export facility on the continent, offered a minimum 6% annual increase for three years.

Volumes shipped at RBCT have dropped to the lowest level in decades because state-owned ports and rail operator Transnet SOC Ltd.’s operations have been hobbled by sabotage, cable theft and aging equipment. The walkout by RBCT workers that began Sept. 17 isn’t affecting operations, Sithole said.

RBCT didn’t comment.

Glencore Plc, Thungela Resources Ltd. and Exxaro Resources Ltd. are among companies that use the terminal to ship coal.