Westlake Chemical's Petro II Ethylene Unit Back in Production

HOUSTON, Oct. 27 /PRNewswire-FirstCall/ -- Westlake Chemical Corporation (NYSE: WLK) announced today that it has successfully restarted its Petro II ethylene unit in Lake Charles, Louisiana after completing mechanical repairs to a compressor and related equipment whose failure had resulted in a shutdown in September. During this shutdown period the company also completed a major turnaround of the unit that was previously scheduled for late this year or early next year. Additionally, the company was able to complete portions of its previously announced feed-flex project while the unit was undergoing the turnaround which will reduce energy costs and provide for additional ethylene capacity.

The company estimates that the negative effect on operating income of the shutdown is in the range of $25 to $30 million resulting from lost production and maintenance repair costs. The capitalized cost of the turnaround work is estimated to be in the range of $25 to $30 million.

The statements in this release relating to the estimated financial effect and costs associated with the shutdown and related repairs, turnaround and project activities are subject to risks and uncertainties and actual results could differ materially. For more detailed information about factors that could cause actual results to differ materially, please refer to Westlake's Annual Report on Form 10-K for the year ended December 31, 2005, which was filed in February 2006.

Westlake Chemical Corporation is an international manufacturer and supplier of petrochemicals, polymers and fabricated products with headquarters in Houston, Texas. The company's range of products includes ethylene, polyethylene, styrene, propylene, caustic, vinyl intermediates, PVC, PVC pipe, PVC windows, fence and decking components. More information on the company can be found at http://www.westlakechemical.com .

CONTACT: media relations, David R. Hansen, or investor relations, Steven Bender, both of Westlake Chemical Corporation, +1-713-960-9111