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<!--Modified on: 10/28/2010 9:35:13 AM-->
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        <link:definition>0205 - Disclosure - Income Taxes</link:definition>
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        <link:definition>0605 - Disclosure - Income Taxes (Details)</link:definition>
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        <link:definition>0608 - Disclosure - Commitments and Contingencies (Details)</link:definition>
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        <link:definition>0603 - Disclosure - Debt (Details)</link:definition>
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        <link:definition>0503 - Disclosure - Debt (Tables)</link:definition>
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      <link:roleType roleURI="http://wm.com/role/CondensedConsolidatingFinancialStatementsDetails" id="CondensedConsolidatingFinancialStatementsDetails">
        <link:definition>0613 - Disclosure - Condensed Consolidating Financial Statements (Details)</link:definition>
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        <link:definition>0607 - Disclosure - Earnings Per Share (Details)</link:definition>
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        <link:definition>0602 - Disclosure - Landfill and Environmental Remediation Liabilities (Details)</link:definition>
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        <link:definition>0507 - Disclosure - Earnings Per Share (Tables)</link:definition>
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        <link:definition>0504 - Disclosure - Derivative Instruments and Hedging Activities (Tables)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>0502 - Disclosure - Landfill and Environmental Remediation Liabilities (Tables)</link:definition>
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        <link:definition>0204 - Disclosure - Derivative Instruments and Hedging Activities</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://wm.com/role/FairValueMeasurementsDetails" id="FairValueMeasurementsDetails">
        <link:definition>0612 - Disclosure - Fair Value Measurements (Details)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://wm.com/role/FairValueMeasurementsTables" id="FairValueMeasurementsTables">
        <link:definition>0512 - Disclosure - Fair Value Measurements (Tables)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://wm.com/role/RestructuringDetails" id="RestructuringDetails">
        <link:definition>0609 - Disclosure - Restructuring (Details)</link:definition>
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        <link:definition>0509 - Disclosure - Restructuring (Tables)</link:definition>
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        <link:definition>0606 - Disclosure - Comprehensive Income (Details)</link:definition>
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        <link:definition>0506 - Disclosure - Comprehensive Income (Tables)</link:definition>
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        <link:definition>0141 - Statement - Condensed Consolidated Statements of Changes in Equity (Unaudited) (Parenthetical)</link:definition>
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        <link:definition>0111 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>0130 - Statement - Condensed Consolidated Statements of Cash Flows (Unaudited)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://wm.com/role/StatementsOfOperations" id="StatementsOfOperations">
        <link:definition>0120 - Statement - Condensed Consolidated Statements of Operations (Unaudited)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:definition>0110 - Statement - Condensed Consolidated Balance Sheets</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://wm.com/role/CondensedConsolidatingFinancialStatements" id="CondensedConsolidatingFinancialStatements">
        <link:definition>0213 - Disclosure - Condensed Consolidating Financial Statements</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
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        <link:definition>0212 - Disclosure - Fair Value Measurements</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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      </link:roleType>
      <link:roleType roleURI="http://wm.com/role/IncomeExpenseFromDivestituresAssetImpairmentsAndUnusualItems" id="IncomeExpenseFromDivestituresAssetImpairmentsAndUnusualItems">
        <link:definition>0211 - Disclosure - (Income) Expense from Divestitures, Asset Impairments and Unusual Items</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:definition>0210 - Disclosure - Segment and Related Information</link:definition>
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        <link:definition>0209 - Disclosure - Restructuring</link:definition>
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        <link:definition>0208 - Disclosure - Commitments and Contingencies</link:definition>
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        <link:definition>0207 - Disclosure - Earnings Per Share</link:definition>
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        <link:definition>0206 - Disclosure - Comprehensive Income</link:definition>
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        <link:definition>0203 - Disclosure - Debt</link:definition>
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        <link:definition>0202 - Disclosure - Landfill and Environmental Remediation Liabilities</link:definition>
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  <element id="wmi_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsCumulativeEffectsOfChangesInAccountingPrinciplesAndNoncontrollingInterest" name="IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsCumulativeEffectsOfChangesInAccountingPrinciplesAndNoncontrollingInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" />
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  <element id="wmi_NumberOfSeparateWageAndHourLawsuitsPendingAgainstCertainOfOurSubsidiariesInCaliforniaEachSeekingClassCertification" name="NumberOfSeparateWageAndHourLawsuitsPendingAgainstCertainOfOurSubsidiariesInCaliforniaEachSeekingClassCertification" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
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  <element id="wmi_FairValueOfRestrictedTrustFundsAndEscrowAccountsForWhichCompanyIsSoleBeneficiarySpecificallyForFutureSettlementOfLandfillAndEnvironmentalRemediationLiabilities" name="FairValueOfRestrictedTrustFundsAndEscrowAccountsForWhichCompanyIsSoleBeneficiarySpecificallyForFutureSettlementOfLandfillAndEnvironmentalRemediationLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" />
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</schema>
</XBRL>
