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  <xs:element id="cwst_LandfillsMember" abstract="true" name="LandfillsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cwst_LettersOfCreditSublimit" abstract="false" name="LettersOfCreditSublimit" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cwst_RollingStockMember" abstract="true" name="RollingStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cwst_LiabilityForClaimsAndClaimsAdjustmentExpenseWorkersCompensationPotentialExposure" abstract="false" name="LiabilityForClaimsAndClaimsAdjustmentExpenseWorkersCompensationPotentialExposure" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cwst_SolidWasteOperationsProcessingMember" abstract="true" name="SolidWasteOperationsProcessingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cwst_NotesPayableMember" abstract="true" name="NotesPayableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cwst_LongTermRevenueBondSeries2013Due2036Member" abstract="true" name="LongTermRevenueBondSeries2013Due2036Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cwst_FinanceAuthorityofMaineSolidWasteDisposalRevenueBondsSeries2005R3FAMEBonds2005R3Member" abstract="true" name="FinanceAuthorityofMaineSolidWasteDisposalRevenueBondsSeries2005R3FAMEBonds2005R3Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cwst_ResourceSolutionsOperationsMember" abstract="true" name="ResourceSolutionsOperationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cwst_EffectiveIncomeTaxRateReconciliationDeferredTaxAdjustmentsAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationDeferredTaxAdjustmentsAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cwst_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsUnvestedWeightedAverageGrantDateFairValue" abstract="false" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsUnvestedWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="cwst_HourlyEmployeeMember" abstract="true" name="HourlyEmployeeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cwst_DebtInstrumentInterestRateAnnualIncreaseUponPaymentDefault" abstract="false" name="DebtInstrumentInterestRateAnnualIncreaseUponPaymentDefault" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="cwst_ResourceSolutionsOperationsProcessingMember" abstract="true" name="ResourceSolutionsOperationsProcessingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cwst_MultiemployerPlansCompleteWithdrawalEstimatedAccumulatedBenefitObligation" abstract="false" name="MultiemployerPlansCompleteWithdrawalEstimatedAccumulatedBenefitObligation" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cwst_EffectiveIncomeTaxRateReconciliationDeductibleStockAwards" abstract="false" name="EffectiveIncomeTaxRateReconciliationDeductibleStockAwards" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cwst_SouthbridgeLandfillMember" abstract="true" name="SouthbridgeLandfillMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cwst_VariableRateComponentOneMember" abstract="true" name="VariableRateComponentOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cwst_RevenueBondsSeriesTwoThousandFourteenDueTwoThousandFortyFourMember" abstract="true" name="RevenueBondsSeriesTwoThousandFourteenDueTwoThousandFortyFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
