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        <link:definition>2427403 - Disclosure - Related Party Transactions (Cost of Sales from Related Parties) (Details)</link:definition>
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        <link:definition>2427407 - Disclosure - Related Party Transactions (Debt Payable to Related Parties) (Details)</link:definition>
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        <link:definition>2427408 - Disclosure - Related Party Transactions (General) (Details)</link:definition>
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        <link:definition>2427405 - Disclosure - Related Party Transactions (Goods and Services from Related Parties that have been Capitalized) (Details)</link:definition>
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        <link:definition>2427402 - Disclosure - Related Party Transactions (Sales to Related Parties) (Details)</link:definition>
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        <link:definition>2427404 - Disclosure - Related Party Transactions (Services from Related Parties Included in SG&amp;A Expenses) (Details)</link:definition>
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        <link:definition>2427409 - Disclosure - Related Party Transactions (Site Lease Agreements) (Details)</link:definition>
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        <link:definition>2327301 - Disclosure - Related Party Transactions (Tables)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType id="SubsequentEvents" roleURI="http://www.westlake.com/role/SubsequentEvents">
        <link:definition>2147100 - Disclosure - Subsequent Events</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>2447401 - Disclosure - Subsequent Events (Details)</link:definition>
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      <link:roleType id="SupplementalInformation" roleURI="http://www.westlake.com/role/SupplementalInformation">
        <link:definition>2144100 - Disclosure - Supplemental Information</link:definition>
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      <link:roleType id="SupplementalInformationDetails" roleURI="http://www.westlake.com/role/SupplementalInformationDetails">
        <link:definition>2444401 - Disclosure - Supplemental Information (Details)</link:definition>
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</xsd:schema>
