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  <xsd:element abstract="true" id="cwst_RevenueBondsSeriesTwoThousandFiveRoneDueTwoThousandTwentyFiveMember" name="RevenueBondsSeriesTwoThousandFiveRoneDueTwoThousandTwentyFiveMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RevenueBondsSeriesTwoThousandFiveRtwoDueTwoThousandTwentyFiveMember" name="RevenueBondsSeriesTwoThousandFiveRtwoDueTwoThousandTwentyFiveMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RevenueBondsSeriesTwoThousandFourteenDueTwoThousandFortyFourMember" name="RevenueBondsSeriesTwoThousandFourteenDueTwoThousandFortyFourMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RevolvingCreditFacilityDue2023Member" name="RevolvingCreditFacilityDue2023Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RevolvingCreditFacilityDueMayTwoThousandTwentyThreeMember" name="RevolvingCreditFacilityDueMayTwoThousandTwentyThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RevolvingCreditFacilitydueOctober2021Member" name="RevolvingCreditFacilitydueOctober2021Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_ScrapYardAndSolidWasteTransferStation" name="ScrapYardAndSolidWasteTransferStation" nillable="true" substitutionGroup="xbrli:item" type="num:areaItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cwst_SeniorSecuredAssetBasedRevolvingCreditFacilityDueTwoThousandAndTwentyThreeMember" name="SeniorSecuredAssetBasedRevolvingCreditFacilityDueTwoThousandAndTwentyThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsNonvestedAggregateIntrinsicValue" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsNonvestedAggregateIntrinsicValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="cwst_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsNonvestedWeightedAverageRemainingContractualTerm" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsNonvestedWeightedAverageRemainingContractualTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsUnvestedNumber" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsUnvestedNumber" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="cwst_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsUnvestedWeightedAverageGrantDateFairValue" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsUnvestedWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="cwst_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsUnvestedAggregateIntrinsicValue" name="SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsUnvestedAggregateIntrinsicValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="cwst_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsUnvestedWeightedAverageRemainingContractualTerm" name="SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsUnvestedWeightedAverageRemainingContractualTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_SolidWasteCollectionBusinessMember" name="SolidWasteCollectionBusinessMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_SolidWasteOperationsCollectionMember" name="SolidWasteOperationsCollectionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_SolidWasteOperationsDisposalMember" name="SolidWasteOperationsDisposalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_SolidWasteOperationsMember" name="SolidWasteOperationsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_SolidWasteOperationsPowerGenerationMember" name="SolidWasteOperationsPowerGenerationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_SolidWasteOperationsProcessingMember" name="SolidWasteOperationsProcessingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_SouthbridgeLandfillMember" name="SouthbridgeLandfillMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_SteadfastInsuranceCompanyMember" name="SteadfastInsuranceCompanyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_StockholdersEquityVotesperShareHeld" name="StockholdersEquityVotesperShareHeld" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_TaxCutsandJobsActof2017ChangeinTaxRateDeferredTaxIncomeTaxExpenseBenefit" name="TaxCutsandJobsActof2017ChangeinTaxRateDeferredTaxIncomeTaxExpenseBenefit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_TermFacilityDueMay2023TermLoanBFacilityMember" name="TermFacilityDueMay2023TermLoanBFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_TermFacilitydue2023TermLoanAFacilityMember" name="TermFacilitydue2023TermLoanAFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_TermFacilitydueOctober2023TermLoanBFacilityMember" name="TermFacilitydueOctober2023TermLoanBFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_TransferMember" name="TransferMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_TransferStationsAcquisitionMember" name="TransferStationsAcquisitionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_TransportationMember" name="TransportationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_TwoThousandSixStockIncentivePlanMember" name="TwoThousandSixStockIncentivePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_UndiscountedCostsPreferredRemedies" name="UndiscountedCostsPreferredRemedies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cwst_VermontEconomicDevelopmentAuthoritySolidWasteDisposalRevenueBondsMember" name="VermontEconomicDevelopmentAuthoritySolidWasteDisposalRevenueBondsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_WesternRegionMember" name="WesternRegionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
</XBRL>
