Subsidiaries of Westlake Chemical Corporation have agreed to reduce harmful air pollution at three chemical plants in the United States

Westlake Chemical Corporation's five subsidiaries — Westlake Chemical OpCo LP, Westlake Petrochemicals LLC, Westlake Polymers LLC, Westlake Styrene LLC, and Westlake Vinyls, Inc. — have agreed to spend $110 million on upgrades and compliance measures to resolve allegations that th...