

<!-- RR Donnelley Xcelerate Taxonomy Schema, based on XBRL 2.1  http://www.rrdonnelley.com/ -->
<!-- Version: 6.21.0 -->
<!-- Round: 6 -->
<!-- Creation date: 2013-06-27T13:50:49Z -->
<!-- Copyright (c) 2005-2013 R.R. Donnelley & Sons Company All Rights Reserved. -->
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        <link:definition>1003 - Statement - CONSOLIDATED BALANCE SHEETS</link:definition>
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        <link:definition>1004 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical)</link:definition>
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        <link:definition>1007 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME</link:definition>
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        <link:definition>1009 - Statement - CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY</link:definition>
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        <link:definition>1010 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS</link:definition>
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        <link:definition>1011 - Disclosure - Basis of Presentation</link:definition>
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        <link:definition>1012 - Disclosure - Summary of Significant Accounting Policies</link:definition>
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        <link:definition>1013 - Disclosure - New Accounting Standards</link:definition>
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        <link:definition>1014 - Disclosure - Business Acquisitions</link:definition>
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        <link:definition>1015 - Disclosure - Restricted Cash / Restricted Assets</link:definition>
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        <link:definition>1016 - Disclosure - Property, Plant and Equipment</link:definition>
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        <link:definition>1017 - Disclosure - Intangible Assets and Goodwill</link:definition>
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        <link:definition>1018 - Disclosure - Accrued Capping, Closure and Post Closure</link:definition>
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        <link:definition>1019 - Disclosure - Other Accrued Liabilities</link:definition>
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        <link:definition>1020 - Disclosure - Long-Term Debt and Capital Leases</link:definition>
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        <link:definition>1021 - Disclosure - Commitments and Contingencies</link:definition>
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        <link:definition>1022 - Disclosure - Stockholders' Equity</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsFairValueDisclosuresTextBlock" id="Role_NotesToFinancialStatementsFairValueDisclosuresTextBlock">
        <link:definition>1023 - Disclosure - Fair Value of Financial Instruments</link:definition>
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        <link:definition>1024 - Disclosure - Employee Benefit Plans</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsIncomeTaxDisclosureTextBlock" id="Role_NotesToFinancialStatementsIncomeTaxDisclosureTextBlock">
        <link:definition>1025 - Disclosure - Income Taxes</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsAbandonedDevelopmentProjectExpenseTextBlock" id="Role_NotesToFinancialStatementsAbandonedDevelopmentProjectExpenseTextBlock">
        <link:definition>1026 - Disclosure - Development Project Charges</link:definition>
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        <link:definition>1027 - Disclosure - Severance and Reorganization</link:definition>
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        <link:definition>1028 - Disclosure - Divestiture Transactions and Discontinued Operations</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsEarningsPerShareTextBlock" id="Role_NotesToFinancialStatementsEarningsPerShareTextBlock">
        <link:definition>1029 - Disclosure - Earnings Per Share</link:definition>
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        <link:definition>1030 - Disclosure - Related Party Transactions</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsSegmentReportingDisclosureTextBlock" id="Role_NotesToFinancialStatementsSegmentReportingDisclosureTextBlock">
        <link:definition>1031 - Disclosure - Segment Reporting</link:definition>
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        <link:usedOn>link:presentationLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsQuarterlyFinancialInformationTextBlock" id="Role_NotesToFinancialStatementsQuarterlyFinancialInformationTextBlock">
        <link:definition>1032 - Disclosure - Quarterly Financial Information</link:definition>
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        <link:usedOn>link:presentationLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsCondensedFinancialStatementsTextBlock" id="Role_NotesToFinancialStatementsCondensedFinancialStatementsTextBlock">
        <link:definition>1033 - Disclosure - Subsidiary Guarantors</link:definition>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsScheduleOfValuationAndQualifyingAccountsDisclosureTextBlock" id="Role_NotesToFinancialStatementsScheduleOfValuationAndQualifyingAccountsDisclosureTextBlock">
        <link:definition>1034 - Disclosure - Schedule II Valuation Accounts</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsSignificantAccountingPoliciesTextBlockPolicies" id="Role_NotesToFinancialStatementsSignificantAccountingPoliciesTextBlockPolicies">
        <link:definition>1035 - Disclosure - Summary of Significant Accounting Policies (Policies)</link:definition>
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        <link:definition>1036 - Disclosure - Summary of Significant Accounting Policies (Tables)</link:definition>
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        <link:usedOn>link:presentationLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsBusinessCombinationDisclosureTextBlockTables" id="Role_NotesToFinancialStatementsBusinessCombinationDisclosureTextBlockTables">
        <link:definition>1037 - Disclosure - Business Acquisitions (Tables)</link:definition>
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        <link:definition>1038 - Disclosure - Restricted Cash / Restricted Assets (Tables)</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsPropertyPlantAndEquipmentDisclosureTextBlockTables" id="Role_NotesToFinancialStatementsPropertyPlantAndEquipmentDisclosureTextBlockTables">
        <link:definition>1039 - Disclosure - Property, Plant and Equipment (Tables)</link:definition>
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        <link:definition>1040 - Disclosure - Intangible Assets and Goodwill (Tables)</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsAssetRetirementObligationDisclosureTextBlockTables" id="Role_NotesToFinancialStatementsAssetRetirementObligationDisclosureTextBlockTables">
        <link:definition>1041 - Disclosure - Accrued Capping, Closure and Post Closure (Tables)</link:definition>
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        <link:definition>1042 - Disclosure - Other Accrued Liabilities (Tables)</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsDebtAndCapitalLeasesDisclosuresTextBlockTables" id="Role_NotesToFinancialStatementsDebtAndCapitalLeasesDisclosuresTextBlockTables">
        <link:definition>1043 - Disclosure - Long-Term Debt and Capital Leases (Tables)</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsCommitmentsAndContingenciesDisclosureTextBlockTables" id="Role_NotesToFinancialStatementsCommitmentsAndContingenciesDisclosureTextBlockTables">
        <link:definition>1044 - Disclosure - Commitments and Contingencies (Tables)</link:definition>
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        <link:definition>1045 - Disclosure - Stockholders' Equity (Tables)</link:definition>
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        <link:definition>1046 - Disclosure - Fair Value of Financial Instruments (Tables)</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsIncomeTaxDisclosureTextBlockTables" id="Role_NotesToFinancialStatementsIncomeTaxDisclosureTextBlockTables">
        <link:definition>1047 - Disclosure - Income Taxes (Tables)</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsDisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlockTables" id="Role_NotesToFinancialStatementsDisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlockTables">
        <link:definition>1048 - Disclosure - Divestiture Transactions and Discontinued Operations (Tables)</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsEarningsPerShareTextBlockTables" id="Role_NotesToFinancialStatementsEarningsPerShareTextBlockTables">
        <link:definition>1049 - Disclosure - Earnings Per Share (Tables)</link:definition>
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        <link:definition>1050 - Disclosure - Segment Reporting (Tables)</link:definition>
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        <link:definition>1051 - Disclosure - Quarterly Financial Information (Tables)</link:definition>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/NotesToFinancialStatementsCondensedFinancialStatementsTextBlockTables" id="Role_NotesToFinancialStatementsCondensedFinancialStatementsTextBlockTables">
        <link:definition>1052 - Disclosure - Subsidiary Guarantors (Tables)</link:definition>
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        <link:definition>1053 - Disclosure - Summary of Significant Accounting Policies - Additional Information (Detail)</link:definition>
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        <link:definition>1080 - Disclosure - Commitments and Contingencies - Reconciliation of Expected Aggregate Undiscounted Amount to Amount Recognized in Statements of Financial Position (Detail)</link:definition>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/DisclosureEarningsPerShareAdditionalInformation" id="DisclosureEarningsPerShareAdditionalInformation">
        <link:definition>1101 - Disclosure - Earnings Per Share - Additional Information (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://casella.com/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformation" id="DisclosureRelatedPartyTransactionsAdditionalInformation">
        <link:definition>1102 - Disclosure - Related Party Transactions - Additional Information (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/DisclosureSegmentReportingSummaryOfFinancialInformationByReportableSegment" id="DisclosureSegmentReportingSummaryOfFinancialInformationByReportableSegment">
        <link:definition>1103 - Disclosure - Segment Reporting - Summary of Financial Information by Reportable Segment (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/DisclosureSegmentReportingSummaryOfRevenueAttributableToServicesProvidedByCompany" id="DisclosureSegmentReportingSummaryOfRevenueAttributableToServicesProvidedByCompany">
        <link:definition>1104 - Disclosure - Segment Reporting - Summary of Revenue Attributable to Services Provided by Company (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/DisclosureQuarterlyFinancialInformationSummaryOfQuarterlyFinancialInformation" id="DisclosureQuarterlyFinancialInformationSummaryOfQuarterlyFinancialInformation">
        <link:definition>1105 - Disclosure - Quarterly Financial Information - Summary of Quarterly Financial Information (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/DisclosureSubsidiaryGuarantorsScheduleOfCondensedConsolidatingBalanceSheet" id="DisclosureSubsidiaryGuarantorsScheduleOfCondensedConsolidatingBalanceSheet">
        <link:definition>1106 - Disclosure - Subsidiary Guarantors - Schedule of Condensed Consolidating Balance Sheet (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:definition>1107 - Disclosure - Subsidiary Guarantors - Schedule of Condensed Consolidating Balance Sheet (Parenthetical) (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/DisclosureSubsidiaryGuarantorsScheduleOfConsolidatingStatementsOfOperations" id="DisclosureSubsidiaryGuarantorsScheduleOfConsolidatingStatementsOfOperations">
        <link:definition>1108 - Disclosure - Subsidiary Guarantors - Schedule of Consolidating Statements of Operations (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/DisclosureSubsidiaryGuarantorsScheduleOfConsolidatingStatementOfComprehensiveIncomeLoss" id="DisclosureSubsidiaryGuarantorsScheduleOfConsolidatingStatementOfComprehensiveIncomeLoss">
        <link:definition>1109 - Disclosure - Subsidiary Guarantors - Schedule of Consolidating Statement of Comprehensive Income (Loss) (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/DisclosureSubsidiaryGuarantorsScheduleOfCondensedConsolidatingStatementOfCashFlows" id="DisclosureSubsidiaryGuarantorsScheduleOfCondensedConsolidatingStatementOfCashFlows">
        <link:definition>1110 - Disclosure - Subsidiary Guarantors - Schedule of Condensed Consolidating Statement of Cash Flows (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://casella.com/taxonomy/role/ScheduleValuationAccounts" id="ScheduleValuationAccounts">
        <link:definition>1111 - Schedule - Valuation Accounts (Detail)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://casella.com/taxonomy/role/StatementOfIncomeAlternativeAlternate1" id="Role_StatementOfIncomeAlternativeAlt1">
        <link:definition>1112 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS (Alternate 1)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:href="cwst-20130430_cal.xml" xlink:title="Calculation Links, all"/>
      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:href="cwst-20130430_def.xml" xlink:title="Definition Links, all"/>
      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:href="cwst-20130430_lab.xml" xlink:title="Label Links, all"/>
      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:href="cwst-20130430_pre.xml" xlink:title="Presentation Links, all"/>
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  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd"/>
  <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd"/>
  <import namespace="http://fasb.org/us-types/2012-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2012/elts/us-types-2012-01-31.xsd"/>
  <import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd"/>
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  <import namespace="http://fasb.org/us-gaap/2012-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/country/2012-01-31" schemaLocation="http://xbrl.sec.gov/country/2012/country-2012-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/dei/2012-01-31" schemaLocation="http://xbrl.sec.gov/dei/2012/dei-2012-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/invest/2012-01-31" schemaLocation="http://xbrl.sec.gov/invest/2012/invest-2012-01-31.xsd"/>
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  <element name="CurrentStateDeferredBenefitLossCarryforwards" id="cwst_CurrentStateDeferredBenefitLossCarryforwards" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="DebtInstrumentRepurchaseTenderedAmount" id="cwst_DebtInstrumentRepurchaseTenderedAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredProjectCosts" id="cwst_DeferredProjectCosts" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredTaxAssetsFederalCapitalLossCarryforwards" id="cwst_DeferredTaxAssetsFederalCapitalLossCarryforwards" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredTaxAssetsLiabilitiesLineItems" id="cwst_DeferredTaxAssetsLiabilitiesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="DeferredTaxAssetsTaxCreditCarryForwardsGeneralBusinessExpirationDate" id="cwst_DeferredTaxAssetsTaxCreditCarryForwardsGeneralBusinessExpirationDate" type="xbrli:stringItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredTaxLiabilityAcquisition" id="cwst_DeferredTaxLiabilityAcquisition" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="DepletionOfLandfillOperatingLeaseObligations" id="cwst_DepletionOfLandfillOperatingLeaseObligations" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DepreciationAmortizationImpairmentLineItems" id="cwst_DepreciationAmortizationImpairmentLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DepreciationAndAmortizationExpensesForPropertyPlantAndEquipmentLineItems" id="cwst_DepreciationAndAmortizationExpensesForPropertyPlantAndEquipmentLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DiscontinuedOperationAdjustmentForNetBookValueOfAssetsDisposed" id="cwst_DiscontinuedOperationAdjustmentForNetBookValueOfAssetsDisposed" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DiscontinuedOperationsAllocatedSharebasedCompensationExpense" id="cwst_DiscontinuedOperationsAllocatedSharebasedCompensationExpense" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DisposalGroupIncludingDiscontinuedOperationNumberOfUnitsRetained" id="cwst_DisposalGroupIncludingDiscontinuedOperationNumberOfUnitsRetained" type="xbrli:integerItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DisposalGroupIncludingDiscontinuedOperationsNumberOfDisposedUnits" id="cwst_DisposalGroupIncludingDiscontinuedOperationsNumberOfDisposedUnits" type="xbrli:integerItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DisposalMember" id="cwst_DisposalMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DivestitureAcquisitionFinancingCosts" id="cwst_DivestitureAcquisitionFinancingCosts" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DivestituresLineItems" id="cwst_DivestituresLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DivestituresTable" id="cwst_DivestituresTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="DocumentDocumentAndEntityInformationAbstract" id="cwst_DocumentDocumentAndEntityInformationAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EarningsLossPerCommonShareAbstract" id="cwst_EarningsLossPerCommonShareAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EarningsPerShareLineItems" id="cwst_EarningsPerShareLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EarningsPerShareTable" id="cwst_EarningsPerShareTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="EasternRegionMember" id="cwst_EasternRegionMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EliminationMember" id="cwst_EliminationMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EmployeeStockPurchasePlanMember" id="cwst_EmployeeStockPurchasePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EmploymentContractsExecutiveOfficers" id="cwst_EmploymentContractsExecutiveOfficers" type="xbrli:integerItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EnvironmentalLiabilitiesLineItems" id="cwst_EnvironmentalLiabilitiesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EnvironmentalLiabilitiesTable" id="cwst_EnvironmentalLiabilitiesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="EquityMethodInvestmentSummarizedFinancialInformationBalanceSheetTableTextBlock" id="cwst_EquityMethodInvestmentSummarizedFinancialInformationBalanceSheetTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EquityMethodInvestmentSummarizedFinancialInformationGrossRevenue" id="cwst_EquityMethodInvestmentSummarizedFinancialInformationGrossRevenue" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EstimatedLongTermInflation" id="cwst_EstimatedLongTermInflation" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisLineItems" id="cwst_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTable" id="cwst_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="FairValueOfAssetsAndLiabilitiesMeasuredOnNonRecurringBasisLineItems" id="cwst_FairValueOfAssetsAndLiabilitiesMeasuredOnNonRecurringBasisLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FameBondsFixed" id="cwst_FameBondsFixed" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FameBondsVariable" id="cwst_FameBondsVariable" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FinancingLeaseObligationCurrent" id="cwst_FinancingLeaseObligationCurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FinancingLeaseObligationNoncurrent" id="cwst_FinancingLeaseObligationNoncurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FinancingLeaseObligations" id="cwst_FinancingLeaseObligations" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FinancingLeaseObligationsFutureMinimumLeasePaymentsInterestIncludedInPayments" id="cwst_FinancingLeaseObligationsFutureMinimumLeasePaymentsInterestIncludedInPayments" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FinancingLeaseObligationsMember" id="cwst_FinancingLeaseObligationsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FiniteLivedIntangibleAssetUsefulLifeMaximum" id="cwst_FiniteLivedIntangibleAssetUsefulLifeMaximum" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FutureRemediationCosts" id="cwst_FutureRemediationCosts" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GainLossOnDisposalOfDiscontinuedOperationNetOfTaxPerBasicAndDilutedShare" id="cwst_GainLossOnDisposalOfDiscontinuedOperationNetOfTaxPerBasicAndDilutedShare" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GainLossOnTender" id="cwst_GainLossOnTender" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GainLossRelatedToLitigationSettlements" id="cwst_GainLossRelatedToLitigationSettlements" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GrantActivityNet" id="cwst_GrantActivityNet" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GrantActivityUnissuedNet" id="cwst_GrantActivityUnissuedNet" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GrantActivityUnissuedStockOptions" id="cwst_GrantActivityUnissuedStockOptions" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GreenFiberMember" id="cwst_GreenFiberMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GuaranteeObligationsAmountPaid" id="cwst_GuaranteeObligationsAmountPaid" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeLossFromOperationsBeforeProvisionBenefitForIncomeTaxesLineItems" id="cwst_IncomeLossFromOperationsBeforeProvisionBenefitForIncomeTaxesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeLossFromOperationsBeforeProvisionBenefitForIncomeTaxesTable" id="cwst_IncomeLossFromOperationsBeforeProvisionBenefitForIncomeTaxesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="IncomeTaxesLineItems" id="cwst_IncomeTaxesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeTaxesTable" id="cwst_IncomeTaxesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="IncomeTaxSettlement" id="cwst_IncomeTaxSettlement" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeTaxSettlementInterestPaid" id="cwst_IncomeTaxSettlementInterestPaid" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeTaxSettlementTaxPaid" id="cwst_IncomeTaxSettlementTaxPaid" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncreaseDecreaseInPrepaidDeferredExpenseInventoryAndOtherAssets" id="cwst_IncreaseDecreaseInPrepaidDeferredExpenseInventoryAndOtherAssets" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InitialTermOfExecutiveEmploymentAgreement" id="cwst_InitialTermOfExecutiveEmploymentAgreement" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IntercompanyBorrowings" id="cwst_IntercompanyBorrowings" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IntercompanyReceivable" id="cwst_IntercompanyReceivable" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InterestCoverageMinimumRatio" id="cwst_InterestCoverageMinimumRatio" type="xbrli:pureItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InterestRateCashFlowHedgesMember" id="cwst_InterestRateCashFlowHedgesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InvestmentInSubsidiaries" id="cwst_InvestmentInSubsidiaries" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LandfillOperatingLeaseMember" id="cwst_LandfillOperatingLeaseMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LandfillOperationAgreements" id="cwst_LandfillOperationAgreements" type="xbrli:integerItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LeaseExtendedPeriod" id="cwst_LeaseExtendedPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LetterOfCreditInterestPercentage" id="cwst_LetterOfCreditInterestPercentage" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LettersOfCredit" id="cwst_LettersOfCredit" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LettersOfCreditFees" id="cwst_LettersOfCreditFees" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LineOfCreditFacilityLettersOfCredit" id="cwst_LineOfCreditFacilityLettersOfCredit" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LineOfCreditFacilityOption" id="cwst_LineOfCreditFacilityOption" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongLivedAssets" id="cwst_LongLivedAssets" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtAndCapitalLeaseMaturitiesRepaymentsOfPrincipalAfterYearFive" id="cwst_LongTermDebtAndCapitalLeaseMaturitiesRepaymentsOfPrincipalAfterYearFive" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtAndCapitalLeaseMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" id="cwst_LongTermDebtAndCapitalLeaseMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtAndCapitalLeaseMaturitiesRepaymentsOfPrincipalInYearFive" id="cwst_LongTermDebtAndCapitalLeaseMaturitiesRepaymentsOfPrincipalInYearFive" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtAndCapitalLeaseMaturitiesRepaymentsOfPrincipalInYearFour" id="cwst_LongTermDebtAndCapitalLeaseMaturitiesRepaymentsOfPrincipalInYearFour" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtAndCapitalLeaseMaturitiesRepaymentsOfPrincipalInYearThree" id="cwst_LongTermDebtAndCapitalLeaseMaturitiesRepaymentsOfPrincipalInYearThree" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtAndCapitalLeaseMaturitiesRepaymentsOfPrincipalInYearTwo" id="cwst_LongTermDebtAndCapitalLeaseMaturitiesRepaymentsOfPrincipalInYearTwo" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtAndCapitalLeaseObligation" id="cwst_LongTermDebtAndCapitalLeaseObligation" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtAndCapitalLeaseObligationsCurrentAndNoncurrent" id="cwst_LongTermDebtAndCapitalLeaseObligationsCurrentAndNoncurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermRevenueBondSeriesTwoThousandThirteenDueTwoThousandThirtySixMember" id="cwst_LongTermRevenueBondSeriesTwoThousandThirteenDueTwoThousandThirtySixMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermRevenueBondSeriesTwoThousandThirteenDueTwoThousandTwentyNineMember" id="cwst_LongTermRevenueBondSeriesTwoThousandThirteenDueTwoThousandTwentyNineMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LossOnConsentPayment" id="cwst_LossOnConsentPayment" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LossOnDivestitureReversal" id="cwst_LossOnDivestitureReversal" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaineBondsMember" id="cwst_MaineBondsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaintenanceMember" id="cwst_MaintenanceMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MarketableSecuritiesMember" id="cwst_MarketableSecuritiesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaterialRecoveryFacilitiesNumber" id="cwst_MaterialRecoveryFacilitiesNumber" type="xbrli:integerItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaximumAccountsReceivableFromSingleCustomerInPercentageToAccountsReceivable" id="cwst_MaximumAccountsReceivableFromSingleCustomerInPercentageToAccountsReceivable" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaximumDebtToEbitdaxRatio" id="cwst_MaximumDebtToEbitdaxRatio" type="xbrli:pureItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaximumFundedDebtToAdjustedEbitdaRatio" id="cwst_MaximumFundedDebtToAdjustedEbitdaRatio" type="xbrli:pureItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaximumNumberOfDaysToEstablishPlansToMonitorComplianceWithConsentOrder" id="cwst_MaximumNumberOfDaysToEstablishPlansToMonitorComplianceWithConsentOrder" type="xbrli:integerItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaximumPotentialSharesIssuedUnderPlan" id="cwst_MaximumPotentialSharesIssuedUnderPlan" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MinorityInterestIncreaseFromContributions" id="cwst_MinorityInterestIncreaseFromContributions" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MotorsLiquidationTrustMember" id="cwst_MotorsLiquidationTrustMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NewHampshireBondsMember" id="cwst_NewHampshireBondsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NonEmployeeDirectorsStockOptionPlanMember" id="cwst_NonEmployeeDirectorsStockOptionPlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NoteReceivableEmployee" id="cwst_NoteReceivableEmployee" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NotesPayableLiabilitiesAssumedAndHoldbacksToSellers" id="cwst_NotesPayableLiabilitiesAssumedAndHoldbacksToSellers" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NotesPayableMember" id="cwst_NotesPayableMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfLandfillsOwnedAndOperatedByCompany" id="cwst_NumberOfLandfillsOwnedAndOperatedByCompany" type="xbrli:integerItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfSingleStreamMaterialRecoveryFacilitiesLeasesFinanced" id="cwst_NumberOfSingleStreamMaterialRecoveryFacilitiesLeasesFinanced" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumeratorAbstract" id="cwst_NumeratorAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OperatingLeaseMonthlyPaymentsMaximum" id="cwst_OperatingLeaseMonthlyPaymentsMaximum" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OperatingLeaseObligationMember" id="cwst_OperatingLeaseObligationMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OtherAccruedLiabilitiesLineItems" id="cwst_OtherAccruedLiabilitiesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OtherAccruedLiabilitiesTable" id="cwst_OtherAccruedLiabilitiesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="OtherSegmentMember" id="cwst_OtherSegmentMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OtherThanStockOptionExpectedToVest" id="cwst_OtherThanStockOptionExpectedToVest" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OtherValuationAllowanceMember" id="cwst_OtherValuationAllowanceMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentPeriod" id="cwst_PaymentPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentsForCapitalExpenditureOnDivestitureOfBusiness" id="cwst_PaymentsForCapitalExpenditureOnDivestitureOfBusiness" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentsForLandfillOperatingLease" id="cwst_PaymentsForLandfillOperatingLease" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentsToAcquireBusinessNetOfCashAcquired" id="cwst_PaymentsToAcquireBusinessNetOfCashAcquired" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentsToAcquireGasRights" id="cwst_PaymentsToAcquireGasRights" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentsToAcquirePropertyPlantAndEquipmentAcquisition" id="cwst_PaymentsToAcquirePropertyPlantAndEquipmentAcquisition" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentsToAcquirePropertyPlantAndEquipmentGrowth" id="cwst_PaymentsToAcquirePropertyPlantAndEquipmentGrowth" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentsToAcquirePropertyPlantAndEquipmentMaintenance" id="cwst_PaymentsToAcquirePropertyPlantAndEquipmentMaintenance" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PercentageByWhichFairValueOfGoodwillExceededCarryingValue" id="cwst_PercentageByWhichFairValueOfGoodwillExceededCarryingValue" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PercentageOfCommoditiesMarketByPurchaser" id="cwst_PercentageOfCommoditiesMarketByPurchaser" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PercentageOfPotentialCumulativeLiability" id="cwst_PercentageOfPotentialCumulativeLiability" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PercentageOrAdditionalPercentageOfEstimatedRemediationCosts" id="cwst_PercentageOrAdditionalPercentageOfEstimatedRemediationCosts" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PerformanceShareUnitsMember" id="cwst_PerformanceShareUnitsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PerformanceStockUnitMember" id="cwst_PerformanceStockUnitMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PlanTerminationDate" id="cwst_PlanTerminationDate" type="us-types:dateStringItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PowerGenerationMember" id="cwst_PowerGenerationMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PremiumOnExtinguishmentOfDebt" id="cwst_PremiumOnExtinguishmentOfDebt" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PresentCostsPreferredRemedies" id="cwst_PresentCostsPreferredRemedies" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrincipalAmountsOfSeniorNotesRepurchased" id="cwst_PrincipalAmountsOfSeniorNotesRepurchased" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProcessingAndOrganicsMember" id="cwst_ProcessingAndOrganicsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProformaDebtInstrumentLineItems" id="cwst_ProformaDebtInstrumentLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PropertyPlantAndEquipmentUsefulLifeAndValuesAbstract" id="cwst_PropertyPlantAndEquipmentUsefulLifeAndValuesAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProvisionForIncomeTaxesLineItems" id="cwst_ProvisionForIncomeTaxesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProvisionForIncomeTaxesTable" id="cwst_ProvisionForIncomeTaxesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="QuarterlyFinancialInformationLineItems" id="cwst_QuarterlyFinancialInformationLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="QuarterlyFinancialInformationTable" id="cwst_QuarterlyFinancialInformationTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="RecourseDebtMember" id="cwst_RecourseDebtMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RecyclingMember" id="cwst_RecyclingMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RelatedPartyLeaseMonthlyPayments" id="cwst_RelatedPartyLeaseMonthlyPayments" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RemarketedBondMember" id="cwst_RemarketedBondMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ReorganizationItemsLineItems" id="cwst_ReorganizationItemsLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ReorganizationItemsTable" id="cwst_ReorganizationItemsTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="ResidentialCartsAndRecyclingBinsMember" id="cwst_ResidentialCartsAndRecyclingBinsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestrictedCashAndInvestmentsLineItems" id="cwst_RestrictedCashAndInvestmentsLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestrictedCashAndInvestmentsTable" id="cwst_RestrictedCashAndInvestmentsTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="RestrictedStockAndRestrictedStockUnitMember" id="cwst_RestrictedStockAndRestrictedStockUnitMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestrictedStockAwardsMember" id="cwst_RestrictedStockAwardsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RevenueBonds" id="cwst_RevenueBonds" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RevenueBondsSeriesTwoThousandFiveRoneDueTwoThousandTwentyFiveMember" id="cwst_RevenueBondsSeriesTwoThousandFiveRoneDueTwoThousandTwentyFiveMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RevenueBondsSeriesTwoThousandFiveRtwoDueTwoThousandTwentyFiveMember" id="cwst_RevenueBondsSeriesTwoThousandFiveRtwoDueTwoThousandTwentyFiveMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RollingStockMember" id="cwst_RollingStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfCondensedComprehensiveIncomeLossTableTextBlock" id="cwst_ScheduleOfCondensedComprehensiveIncomeLossTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfEquityMethodInvestmentSummarizedFinancialInformationTableTextBlock" id="cwst_ScheduleOfEquityMethodInvestmentSummarizedFinancialInformationTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfFutureEnvironmentalRemediationPaymentsTableTextBlock" id="cwst_ScheduleOfFutureEnvironmentalRemediationPaymentsTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfInterestExpensesLineItems" id="cwst_ScheduleOfInterestExpensesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfInterestExpensesTable" id="cwst_ScheduleOfInterestExpensesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="ScheduleOfOperatingAndCapitalLeasesFutureMinimumPaymentsDueLineItems" id="cwst_ScheduleOfOperatingAndCapitalLeasesFutureMinimumPaymentsDueLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfOperatingAndCapitalLeasesFutureMinimumPaymentsDueTable" id="cwst_ScheduleOfOperatingAndCapitalLeasesFutureMinimumPaymentsDueTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="ScheduleOfPropertyPlantAndEquipmentEstimatedUsefulLifeTableTextBlock" id="cwst_ScheduleOfPropertyPlantAndEquipmentEstimatedUsefulLifeTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfReconciliationOfExpectedUndiscountedLiabilityToActualLiabilityTableTextBlock" id="cwst_ScheduleOfReconciliationOfExpectedUndiscountedLiabilityToActualLiabilityTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfResultsRelatedToEquityAccountedInvesteesLineItems" id="cwst_ScheduleOfResultsRelatedToEquityAccountedInvesteesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfShareBasedCompensationOfStockOptionsRestrictedStockUnitsAndPerformanceBasedUnitsActivityTableTextBlock" id="cwst_ScheduleOfShareBasedCompensationOfStockOptionsRestrictedStockUnitsAndPerformanceBasedUnitsActivityTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfShareBasedPaymentAwardsGrantedByAwardTypeTableTextBlock" id="cwst_ScheduleOfShareBasedPaymentAwardsGrantedByAwardTypeTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfStockOptionActivityLineItems" id="cwst_ScheduleOfStockOptionActivityLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfStockOptionActivityTable" id="cwst_ScheduleOfStockOptionActivityTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="ScrapYardAndSolidWasteTransferStation" id="cwst_ScrapYardAndSolidWasteTransferStation" type="xbrli:integerItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SecondLienNotesMember" id="cwst_SecondLienNotesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeniorNotesOutstanding" id="cwst_SeniorNotesOutstanding" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeniorSecuredRevolvingCreditFacilityDueTwoThousandAndSixteenMember" id="cwst_SeniorSecuredRevolvingCreditFacilityDueTwoThousandAndSixteenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeniorSecuredRevolvingCreditFacilityMember" id="cwst_SeniorSecuredRevolvingCreditFacilityMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeniorSecuredSecondLienNotesDueTwoThousandFourteenMember" id="cwst_SeniorSecuredSecondLienNotesDueTwoThousandFourteenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeniorSubordinatedNotesDueTwoThousandNineteenMember" id="cwst_SeniorSubordinatedNotesDueTwoThousandNineteenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeniorSubordinatedNotesDueTwoThousandThirteenMember" id="cwst_SeniorSubordinatedNotesDueTwoThousandThirteenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeniorSubordinatedNotesRemainingOutstanding" id="cwst_SeniorSubordinatedNotesRemainingOutstanding" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeveranceAndReorganizationLiability" id="cwst_SeveranceAndReorganizationLiability" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardTargetPerformanceRate" id="cwst_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardTargetPerformanceRate" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardRestrictedStockUnitOtherThanOptionsNonvestedNumber" id="cwst_ShareBasedCompensationArrangementByShareBasedPaymentAwardRestrictedStockUnitOtherThanOptionsNonvestedNumber" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SizeOfContainers" id="cwst_SizeOfContainers" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SolidWasteOperationsMember" id="cwst_SolidWasteOperationsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SoutheasternMassachusettsMember" id="cwst_SoutheasternMassachusettsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockholdersEquityExcludingPortionAttributableToSubsidiariesNoncontrollingInterestAbstract" id="cwst_StockholdersEquityExcludingPortionAttributableToSubsidiariesNoncontrollingInterestAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuedDuringPeriodSharesAcquisitionsAndForServices" id="cwst_StockIssuedDuringPeriodSharesAcquisitionsAndForServices" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuedDuringPeriodValueAcquisitionAndForServices" id="cwst_StockIssuedDuringPeriodValueAcquisitionAndForServices" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockOptionPlanMember" id="cwst_StockOptionPlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockOptionsPerformanceStockUnitsRestrictedStockUnitsAndRestrictedStockMember" id="cwst_StockOptionsPerformanceStockUnitsRestrictedStockUnitsAndRestrictedStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SummaryOfSignificantAccountingPoliciesLineItems" id="cwst_SummaryOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SummaryOfSignificantAccountingPoliciesTable" id="cwst_SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="SuretyBonds" id="cwst_SuretyBonds" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TompkinsCountyRecyclingLlcMember" id="cwst_TompkinsCountyRecyclingLlcMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TrilogyGlassMember" id="cwst_TrilogyGlassMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandAndThirteenNotesMember" id="cwst_TwoThousandAndThirteenNotesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandElevenRevolvingCreditFacilityMember" id="cwst_TwoThousandElevenRevolvingCreditFacilityMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandNineMember" id="cwst_TwoThousandNineMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandNineteenNotesMember" id="cwst_TwoThousandNineteenNotesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandSixStockIncentivePlanMember" id="cwst_TwoThousandSixStockIncentivePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UndiscountedCostsPreferredRemedies" id="cwst_UndiscountedCostsPreferredRemedies" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnrecognizedShareBasedCompensationRestrictedStockAndUnitExpenseWeightedAverageAmortizationPeriodRemainingYears" id="cwst_UnrecognizedShareBasedCompensationRestrictedStockAndUnitExpenseWeightedAverageAmortizationPeriodRemainingYears" type="xbrli:decimalItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnrecognizedStockBasedCompensationExpense" id="cwst_UnrecognizedStockBasedCompensationExpense" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnvestedOptionsMember" id="cwst_UnvestedOptionsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnvestedRestrictedStockAwards" id="cwst_UnvestedRestrictedStockAwards" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="VariableRateBondsMember" id="cwst_VariableRateBondsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="VedaBonds" id="cwst_VedaBonds" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="VermontBondsMember" id="cwst_VermontBondsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="VestedStockOptionsMember" id="cwst_VestedStockOptionsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WasteStreamIncMember" id="cwst_WasteStreamIncMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WeightedAverageDiscountRateMaximum" id="cwst_WeightedAverageDiscountRateMaximum" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WeightedAverageDiscountRateMinimum" id="cwst_WeightedAverageDiscountRateMinimum" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WeightedAverageNumberOfCommonSharesOutstandingAbstract" id="cwst_WeightedAverageNumberOfCommonSharesOutstandingAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WesternRegionMember" id="cwst_WesternRegionMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WorkersCompensationBenefits" id="cwst_WorkersCompensationBenefits" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WorkingCapitalAdjustment" id="cwst_WorkingCapitalAdjustment" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WriteOffDebtDiscount" id="cwst_WriteOffDebtDiscount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
</schema>





