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  <xs:element id="cwst_NCESLandfilMember" abstract="true" name="NCESLandfilMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_SolidWasteOperationsCollectionMember" abstract="true" name="SolidWasteOperationsCollectionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_CashFlowOperatingandFinancingActivitiesLesseeAbstract" abstract="true" name="CashFlowOperatingandFinancingActivitiesLesseeAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cwst_SouthbridgeLandfillMember" abstract="true" name="SouthbridgeLandfillMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_PerformanceStockUnitMember" abstract="true" name="PerformanceStockUnitMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour" abstract="false" name="FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cwst_OrganicsMember" abstract="true" name="OrganicsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_TransferMember" abstract="true" name="TransferMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_CreditFacilityMember" abstract="true" name="CreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_A21ESettlementandWaterSystemConstructionFundingAgreementMember" abstract="true" name="A21ESettlementandWaterSystemConstructionFundingAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_FinanceLeaseLiabilityToBePaidAfterYearFour" abstract="false" name="FinanceLeaseLiabilityToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cwst_SolidWasteOperationsDisposalMember" abstract="true" name="SolidWasteOperationsDisposalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_StockholdersEquityVotesperShareHeld" abstract="false" name="StockholdersEquityVotesperShareHeld" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="cwst_NonEmployeeDirectorMember" abstract="true" name="NonEmployeeDirectorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_SupplementalCashFlowInformationCashPaidAbstract" abstract="true" name="SupplementalCashFlowInformationCashPaidAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cwst_PercentageParticipationInOnsiteRemediationActivities" abstract="false" name="PercentageParticipationInOnsiteRemediationActivities" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="cwst_SouthbridgeLandfillClosureCharge" abstract="false" name="SouthbridgeLandfillClosureCharge" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cwst_AdditionalSharesIssuedMaximumAttainmentLevel" abstract="false" name="AdditionalSharesIssuedMaximumAttainmentLevel" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="cwst_RevenueBondsSeriesTwoThousandFourteenDueTwoThousandFortyFourMember" abstract="true" name="RevenueBondsSeriesTwoThousandFourteenDueTwoThousandFortyFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_RevolvingCreditFacilityDueMayTwoThousandTwentyThreeMember" abstract="true" name="RevolvingCreditFacilityDueMayTwoThousandTwentyThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_FinanceAuthorityOfMaineSolidWasteDisposalRevenueBondsSeries2015R2Member" abstract="true" name="FinanceAuthorityOfMaineSolidWasteDisposalRevenueBondsSeries2015R2Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_SolidWasteOperationsPowerGenerationMember" abstract="true" name="SolidWasteOperationsPowerGenerationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="cwst_AccrualForEnvironmentalLossContingenciesObligationsIncurred" abstract="false" name="AccrualForEnvironmentalLossContingenciesObligationsIncurred" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
