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  <xs:element id="cwst_SolidWasteOperationsLandfillGasToEnergyMember" abstract="true" name="SolidWasteOperationsLandfillGasToEnergyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cwst_SolidWasteOperationsProcessingMember" abstract="true" name="SolidWasteOperationsProcessingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cwst_ResourceSolutionsOperationsMember" abstract="true" name="ResourceSolutionsOperationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cwst_ResourceSolutionsOperationsProcessingMember" abstract="true" name="ResourceSolutionsOperationsProcessingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
</xs:schema>
