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  <xsd:element abstract="true" id="cwst_RevenueBondSeriesTwoThousandThirteenDueTwoThousandTwentyNineMember" name="RevenueBondSeriesTwoThousandThirteenDueTwoThousandTwentyNineMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RevenueBondsSeriesTwoThousandFifteenDueTwoThousandThirtyFiveMember" name="RevenueBondsSeriesTwoThousandFifteenDueTwoThousandThirtyFiveMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <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_RevenueBondsSeriesTwoThousandFourteenDueTwoThousandFortyFourMember" name="RevenueBondsSeriesTwoThousandFourteenDueTwoThousandFortyFourMember" 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 abstract="true" id="cwst_RollingStockMember" name="RollingStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_ScheduleOfFutureEnvironmentalRemediationPaymentsTableTextBlock" name="ScheduleOfFutureEnvironmentalRemediationPaymentsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_ScheduleofReconciliationofExpectedUndiscountedLiabilityToActualLiabilityTableTextBlock" name="ScheduleofReconciliationofExpectedUndiscountedLiabilityToActualLiabilityTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" 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_SeniorSecuredAssetBasedRevolvingCreditFacilityDueTwoThousandAndTwentyMember" name="SeniorSecuredAssetBasedRevolvingCreditFacilityDueTwoThousandAndTwentyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_SeniorSubordinatedNotesDueTwoThousandNineteenMember" name="SeniorSubordinatedNotesDueTwoThousandNineteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_SettlementPayment" name="SettlementPayment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="cwst_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestAggregateIntrinsicValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestAggregateIntrinsicValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="cwst_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestNumber" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestNumber" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="cwst_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="cwst_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageRemainingContractualTerms" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageRemainingContractualTerms" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <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 id="cwst_SharebasedCompensationArrangementsbySharebasedPaymentAwardOptionsGrantsinPeriodMonteCarloOptionPricingModelWeightedAverageExercisePrice" name="SharebasedCompensationArrangementsbySharebasedPaymentAwardOptionsGrantsinPeriodMonteCarloOptionPricingModelWeightedAverageExercisePrice" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" 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_SouthbridgeRecyclingDisposalParkInc.vsSouthbridgeMassachusettsMember" name="SouthbridgeRecyclingDisposalParkInc.vsSouthbridgeMassachusettsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_StockOptionsPerformanceStockUnitsRestrictedStockUnitsAndRestrictedStockMember" name="StockOptionsPerformanceStockUnitsRestrictedStockUnitsAndRestrictedStockMember" 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_SuretyBonds" name="SuretyBonds" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_TermFacilitydueOctober2023Member" name="TermFacilitydueOctober2023Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_TompkinsCountyRecyclingLlcMember" name="TompkinsCountyRecyclingLlcMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_TompkinsMember" name="TompkinsMember" 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 id="cwst_UnrecognizedTaxBenefitsIncreaseResultingFromLapseOfApplicableStatuteOfLimitations" name="UnrecognizedTaxBenefitsIncreaseResultingFromLapseOfApplicableStatuteOfLimitations" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_UponExecutionofSettlementAgreementMember" name="UponExecutionofSettlementAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_VariableRateBondsMember" name="VariableRateBondsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_VermontBondsMember" name="VermontBondsMember" 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>





