Americas Styrenics plans to build a deep-water dock at its styrene production facility in St. James.

The styrene monomer the plant makes is one of the basic building blocks of the plastics industry. The material is used to make the plastic polystyrene. Styrene monomer is also used to make packaging, electronic parts, rubber products, paper, housewares, construction materials, carpeting and toys.

AmSty said Thursday that detailed engineering is underway on the project, and American Styrenics expects the dock will be operating in late 2015.

The project will allow the St. James facility to handle large ocean-going vessels “critical to feedstock imports,” said Randy Pogue, vice president-styrene, feedstocks and corporate services. The new dock will also support the company’s styrene export business.

The St. James plant is a joint venture by Chevron Phillips Chemical Co. LP and Styron, a global materials company and plastics maker.