<XBRL>
<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<xsd:schema attributeFormDefault="unqualified" elementFormDefault="qualified" targetNamespace="http://casella.com/20181231" xmlns:cwst="http://casella.com/20181231" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:nonnum="http://www.xbrl.org/dtr/type/non-numeric" xmlns:num="http://www.xbrl.org/dtr/type/numeric" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <xsd:import namespace="http://fasb.org/us-gaap/2017-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd" />
  <xsd:import namespace="http://fasb.org/us-roles/2017-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2017/elts/us-roles-2017-01-31.xsd" />
  <xsd:import namespace="http://fasb.org/us-types/2017-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2017/elts/us-types-2017-01-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/arcrole/fact-explanatoryFact" schemaLocation="http://www.xbrl.org/lrr/arcrole/factExplanatory-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/net" schemaLocation="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd" />
  <xsd:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/country/2017-01-31" schemaLocation="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/currency/2017-01-31" schemaLocation="http://xbrl.sec.gov/currency/2017/currency-2017-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/dei/2014-01-31" schemaLocation="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/exch/2017-01-31" schemaLocation="http://xbrl.sec.gov/exch/2017/exch-2017-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/invest/2013-01-31" schemaLocation="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/naics/2017-01-31" schemaLocation="http://xbrl.sec.gov/naics/2017/naics-2017-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/sic/2011-01-31" schemaLocation="http://xbrl.sec.gov/sic/2011/sic-2011-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/stpr/2011-01-31" schemaLocation="http://xbrl.sec.gov/stpr/2011/stpr-2011-01-31.xsd" />
  <xsd:annotation>
    <xsd:appinfo>
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="cwst-20181231_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:type="simple" />
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="cwst-20181231_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:type="simple" />
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="cwst-20181231_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:type="simple" />
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="cwst-20181231_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:type="simple" />
      <link:roleType id="AccountingChanges" roleURI="http://casella.com/role/AccountingChanges">
        <link:definition>2102100 - Disclosure - ACCOUNTING CHANGES</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="AccountingChangesDetails" roleURI="http://casella.com/role/AccountingChangesDetails">
        <link:definition>2402403 - Disclosure - ACCOUNTING CHANGES (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="AccountingChangesPolicies" roleURI="http://casella.com/role/AccountingChangesPolicies">
        <link:definition>2202201 - Disclosure - ACCOUNTING CHANGES (Policies)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="AccountingChangesTables" roleURI="http://casella.com/role/AccountingChangesTables">
        <link:definition>2302302 - Disclosure - ACCOUNTING CHANGES (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BasisOfPresentation" roleURI="http://casella.com/role/BasisOfPresentation">
        <link:definition>2101100 - Disclosure - BASIS OF PRESENTATION</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BasisOfPresentationDetail" roleURI="http://casella.com/role/BasisOfPresentationDetail">
        <link:definition>2401401 - Disclosure - BASIS OF PRESENTATION (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BusinessCombinations" roleURI="http://casella.com/role/BusinessCombinations">
        <link:definition>2105100 - Disclosure - BUSINESS COMBINATIONS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BusinessCombinationsNarrativeDetail" roleURI="http://casella.com/role/BusinessCombinationsNarrativeDetail">
        <link:definition>2405402 - Disclosure - BUSINESS COMBINATIONS - Narrative (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BusinessCombinationsScheduleOfPurchasePricePaidForAcquisitionsDetail" roleURI="http://casella.com/role/BusinessCombinationsScheduleOfPurchasePricePaidForAcquisitionsDetail">
        <link:definition>2405403 - Disclosure - BUSINESS COMBINATIONS - Schedule of Purchase Price Paid for Acquisitions (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BusinessCombinationsScheduleOfUnauditedProFormaCombinedInformationDetail" roleURI="http://casella.com/role/BusinessCombinationsScheduleOfUnauditedProFormaCombinedInformationDetail">
        <link:definition>2405404 - Disclosure - BUSINESS COMBINATIONS - Schedule of Unaudited Pro forma Combined Information (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BusinessCombinationsTables" roleURI="http://casella.com/role/BusinessCombinationsTables">
        <link:definition>2305301 - Disclosure - BUSINESS COMBINATIONS (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsAndContingencies" roleURI="http://casella.com/role/CommitmentsAndContingencies">
        <link:definition>2111100 - Disclosure - COMMITMENTS AND CONTINGENCIES</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsAndContingenciesNarrativeDetail" roleURI="http://casella.com/role/CommitmentsAndContingenciesNarrativeDetail">
        <link:definition>2411402 - Disclosure - COMMITMENTS AND CONTINGENCIES - Narrative (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsAndContingenciesReconciliationOfExpectedAggregateNonInflatedUndiscountedAmountToAmountRecognizedInStatementsOfFinancialPositionDetail" roleURI="http://casella.com/role/CommitmentsAndContingenciesReconciliationOfExpectedAggregateNonInflatedUndiscountedAmountToAmountRecognizedInStatementsOfFinancialPositionDetail">
        <link:definition>2411407 - Disclosure - COMMITMENTS AND CONTINGENCIES - Reconciliation of Expected Aggregate Non-inflated, Undiscounted Amount to Amount Recognized in Statements of Financial Position (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsAndContingenciesScheduleOfEnvironmentalLiabilityAssociatedWithPotsdamDetail" roleURI="http://casella.com/role/CommitmentsAndContingenciesScheduleOfEnvironmentalLiabilityAssociatedWithPotsdamDetail">
        <link:definition>2411405 - Disclosure - COMMITMENTS AND CONTINGENCIES - Schedule of Environmental Liability Associated with Potsdam (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsAndContingenciesScheduleOfEnvironmentalLiabilityAssociatedWithSouthbridgeLandfillDetails" roleURI="http://casella.com/role/CommitmentsAndContingenciesScheduleOfEnvironmentalLiabilityAssociatedWithSouthbridgeLandfillDetails">
        <link:definition>2411404 - Disclosure - COMMITMENTS AND CONTINGENCIES - Schedule of Environmental Liability Associated with Southbridge Landfill (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsAndContingenciesScheduleOfFutureMinimumRentalDetail" roleURI="http://casella.com/role/CommitmentsAndContingenciesScheduleOfFutureMinimumRentalDetail">
        <link:definition>2411406 - Disclosure - COMMITMENTS AND CONTINGENCIES - Schedule of Future Minimum Rental (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsAndContingenciesScheduleOfFutureMinimumRentalPaymentsUnderNonCancellableOperatingLeasesDetail" roleURI="http://casella.com/role/CommitmentsAndContingenciesScheduleOfFutureMinimumRentalPaymentsUnderNonCancellableOperatingLeasesDetail">
        <link:definition>2411403 - Disclosure - COMMITMENTS AND CONTINGENCIES - Schedule of Future Minimum Rental Payments under Non-Cancellable Operating Leases (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsAndContingenciesTables" roleURI="http://casella.com/role/CommitmentsAndContingenciesTables">
        <link:definition>2311301 - Disclosure - COMMITMENTS AND CONTINGENCIES (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedBalanceSheets" roleURI="http://casella.com/role/ConsolidatedBalanceSheets">
        <link:definition>1001000 - Statement - CONSOLIDATED BALANCE SHEETS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedBalanceSheetsParenthetical" roleURI="http://casella.com/role/ConsolidatedBalanceSheetsParenthetical">
        <link:definition>1001501 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedStatementOfStockholdersDeficit" roleURI="http://casella.com/role/ConsolidatedStatementOfStockholdersDeficit">
        <link:definition>1004000 - Statement - CONSOLIDATED STATEMENT OF STOCKHOLDERS' DEFICIT</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedStatementsOfCashFlows" roleURI="http://casella.com/role/ConsolidatedStatementsOfCashFlows">
        <link:definition>1005000 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedStatementsOfComprehensiveIncomeLoss" roleURI="http://casella.com/role/ConsolidatedStatementsOfComprehensiveIncomeLoss">
        <link:definition>1003000 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedStatementsOfOperations" roleURI="http://casella.com/role/ConsolidatedStatementsOfOperations">
        <link:definition>1002000 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedStatementsOfOperationsCalc2" roleURI="http://casella.com/role/ConsolidatedStatementsOfOperationsCalc2">
        <link:definition>1002000 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DocumentAndEntityInformation" roleURI="http://casella.com/role/DocumentAndEntityInformation">
        <link:definition>0001000 - Document - Document and Entity Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EarningsPerShare" roleURI="http://casella.com/role/EarningsPerShare">
        <link:definition>2116100 - Disclosure - EARNINGS PER SHARE</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EarningsPerShareDetail" roleURI="http://casella.com/role/EarningsPerShareDetail">
        <link:definition>2416402 - Disclosure - EARNINGS PER SHARE (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EarningsPerShareTables" roleURI="http://casella.com/role/EarningsPerShareTables">
        <link:definition>2316301 - Disclosure - EARNINGS PER SHARE (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EmployeeBenefitPlans" roleURI="http://casella.com/role/EmployeeBenefitPlans">
        <link:definition>2114100 - Disclosure - EMPLOYEE BENEFIT PLANS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EmployeeBenefitPlansEmployeeBenefitPlansTables" roleURI="http://casella.com/role/EmployeeBenefitPlansEmployeeBenefitPlansTables">
        <link:definition>2314301 - Disclosure - EMPLOYEE BENEFIT PLANS EMPLOYEE BENEFIT PLANS (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EmployeeBenefitPlansMultiemployerDefinedBenefitPensionPlanDetails" roleURI="http://casella.com/role/EmployeeBenefitPlansMultiemployerDefinedBenefitPensionPlanDetails">
        <link:definition>2414403 - Disclosure - EMPLOYEE BENEFIT PLANS - Multiemployer Defined Benefit Pension Plan (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EmployeeBenefitPlansNarrativeDetail" roleURI="http://casella.com/role/EmployeeBenefitPlansNarrativeDetail">
        <link:definition>2414402 - Disclosure - EMPLOYEE BENEFIT PLANS - Narrative (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueOfFinancialInstruments" roleURI="http://casella.com/role/FairValueOfFinancialInstruments">
        <link:definition>2113100 - Disclosure - FAIR VALUE OF FINANCIAL INSTRUMENTS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueOfFinancialInstrumentsDetail" roleURI="http://casella.com/role/FairValueOfFinancialInstrumentsDetail">
        <link:definition>2413402 - Disclosure - FAIR VALUE OF FINANCIAL INSTRUMENTS (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueOfFinancialInstrumentsTables" roleURI="http://casella.com/role/FairValueOfFinancialInstrumentsTables">
        <link:definition>2313301 - Disclosure - FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FinalCappingClosureAndPostClosureCosts" roleURI="http://casella.com/role/FinalCappingClosureAndPostClosureCosts">
        <link:definition>2109100 - Disclosure - FINAL CAPPING, CLOSURE AND POST-CLOSURE COSTS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FinalCappingClosureAndPostClosureCostsDetail" roleURI="http://casella.com/role/FinalCappingClosureAndPostClosureCostsDetail">
        <link:definition>2409402 - Disclosure - FINAL CAPPING, CLOSURE AND POST-CLOSURE COSTS (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FinalCappingClosureAndPostClosureCostsTables" roleURI="http://casella.com/role/FinalCappingClosureAndPostClosureCostsTables">
        <link:definition>2309301 - Disclosure - FINAL CAPPING, CLOSURE AND POST-CLOSURE COSTS (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillAndIntangibleAssets" roleURI="http://casella.com/role/GoodwillAndIntangibleAssets">
        <link:definition>2108100 - Disclosure - GOODWILL AND INTANGIBLE ASSETS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillAndIntangibleAssetsComponentsOfIntangibleAssetsDetail" roleURI="http://casella.com/role/GoodwillAndIntangibleAssetsComponentsOfIntangibleAssetsDetail">
        <link:definition>2408403 - Disclosure - GOODWILL AND INTANGIBLE ASSETS - Components of Intangible Assets (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillAndIntangibleAssetsEstimatedFutureAmortizationExpenseDetail" roleURI="http://casella.com/role/GoodwillAndIntangibleAssetsEstimatedFutureAmortizationExpenseDetail">
        <link:definition>2408404 - Disclosure - GOODWILL AND INTANGIBLE ASSETS - Estimated Future Amortization Expense (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillAndIntangibleAssetsScheduleOfActivityAndBalancesRelatedToGoodwillByReportingSegmentDetail" roleURI="http://casella.com/role/GoodwillAndIntangibleAssetsScheduleOfActivityAndBalancesRelatedToGoodwillByReportingSegmentDetail">
        <link:definition>2408402 - Disclosure - GOODWILL AND INTANGIBLE ASSETS - Schedule of Activity and Balances Related to Goodwill by Reporting Segment (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillAndIntangibleAssetsTables" roleURI="http://casella.com/role/GoodwillAndIntangibleAssetsTables">
        <link:definition>2308301 - Disclosure - GOODWILL AND INTANGIBLE ASSETS (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxes" roleURI="http://casella.com/role/IncomeTaxes">
        <link:definition>2115100 - Disclosure - INCOME TAXES</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesNarrativeDetail" roleURI="http://casella.com/role/IncomeTaxesNarrativeDetail">
        <link:definition>2415403 - Disclosure - INCOME TAXES - Narrative (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail" roleURI="http://casella.com/role/IncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail">
        <link:definition>2415405 - Disclosure - INCOME TAXES - Schedule of Deferred Tax Assets and Liabilities (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesScheduleOfDifferenceInProvisionBenefitForIncomeTaxesDetail" roleURI="http://casella.com/role/IncomeTaxesScheduleOfDifferenceInProvisionBenefitForIncomeTaxesDetail">
        <link:definition>2415404 - Disclosure - INCOME TAXES - Schedule of Difference in Provision (Benefit) for Income Taxes (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesScheduleOfProvisionBenefitForIncomeTaxesContinuingOperationsDetail" roleURI="http://casella.com/role/IncomeTaxesScheduleOfProvisionBenefitForIncomeTaxesContinuingOperationsDetail">
        <link:definition>2415402 - Disclosure - INCOME TAXES - Schedule of Provision (Benefit) for Income Taxes Continuing Operations (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesScheduleOfReconciliationOfGrossUnrecognizedTaxBenefitsDetail" roleURI="http://casella.com/role/IncomeTaxesScheduleOfReconciliationOfGrossUnrecognizedTaxBenefitsDetail">
        <link:definition>2415406 - Disclosure - INCOME TAXES - Schedule of Reconciliation of Gross Unrecognized Tax Benefits (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesTables" roleURI="http://casella.com/role/IncomeTaxesTables">
        <link:definition>2315301 - Disclosure - INCOME TAXES (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeases" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeases">
        <link:definition>2110100 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeasesCashFlowHedgesDetails" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeasesCashFlowHedgesDetails">
        <link:definition>2410407 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES - Cash Flow Hedges (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeasesComponentsOfInterestExpenseDetails" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeasesComponentsOfInterestExpenseDetails">
        <link:definition>2410406 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES - Components of Interest Expense (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeasesComponentsOfLongTermDebtAndCapitalLeasesDetails" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeasesComponentsOfLongTermDebtAndCapitalLeasesDetails">
        <link:definition>2410402 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES - Components of Long-Term Debt and Capital Leases (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeasesComponentsOfLongTermDebtAndCapitalLeasesDetailsCalc2" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeasesComponentsOfLongTermDebtAndCapitalLeasesDetailsCalc2">
        <link:definition>2410402 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES - Components of Long-Term Debt and Capital Leases (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeasesCreditFacilityDetails" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeasesCreditFacilityDetails">
        <link:definition>2410403 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES - Credit Facility (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeasesFairValueOfDebtDetails" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeasesFairValueOfDebtDetails">
        <link:definition>2410410 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES - Fair Value of Debt (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeasesLossOnDebtExtinguishmentDetails" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeasesLossOnDebtExtinguishmentDetails">
        <link:definition>2410405 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES - Loss on Debt Extinguishment (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeasesScheduleOfCashFlowHedgesRelatedToDerivativeInstrumentsOnBalanceSheetDetails" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeasesScheduleOfCashFlowHedgesRelatedToDerivativeInstrumentsOnBalanceSheetDetails">
        <link:definition>2410408 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES - Schedule of Cash Flow Hedges Related to Derivative Instruments on the Balance Sheet  (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeasesScheduleOfFutureMaturitiesOfDebtDetails" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeasesScheduleOfFutureMaturitiesOfDebtDetails">
        <link:definition>2410411 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES - Schedule of Future Maturities of Debt (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeasesScheduleOfGainLossOnCashFlowHedgesDetails" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeasesScheduleOfGainLossOnCashFlowHedgesDetails">
        <link:definition>2410409 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES - Schedule of Gain (Loss) On Cash Flow Hedges (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeasesTables" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeasesTables">
        <link:definition>2310301 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtAndCapitalLeasesTaxExemptFinancingsDetails" roleURI="http://casella.com/role/LongTermDebtAndCapitalLeasesTaxExemptFinancingsDetails">
        <link:definition>2410404 - Disclosure - LONG TERM DEBT AND CAPITAL LEASES - Tax-Exempt Financings (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OtherItemsAndCharges" roleURI="http://casella.com/role/OtherItemsAndCharges">
        <link:definition>2116100 - Disclosure - OTHER ITEMS AND CHARGES</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OtherItemsAndChargesChargesAssociatedWithClosureOfSouthbridgeLandfillDetail" roleURI="http://casella.com/role/OtherItemsAndChargesChargesAssociatedWithClosureOfSouthbridgeLandfillDetail">
        <link:definition>2416402 - Disclosure - OTHER ITEMS AND CHARGES - Charges Associated with Closure of Southbridge Landfill (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OtherItemsAndChargesOtherItemsAndChargesNarrativeDetails" roleURI="http://casella.com/role/OtherItemsAndChargesOtherItemsAndChargesNarrativeDetails">
        <link:definition>2416403 - Disclosure - OTHER ITEMS AND CHARGES OTHER ITEMS AND CHARGES - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OtherItemsAndChargesOtherItemsAndChargesTables" roleURI="http://casella.com/role/OtherItemsAndChargesOtherItemsAndChargesTables">
        <link:definition>2316301 - Disclosure - OTHER ITEMS AND CHARGES OTHER ITEMS AND CHARGES (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PropertyPlantAndEquipment" roleURI="http://casella.com/role/PropertyPlantAndEquipment">
        <link:definition>2107100 - Disclosure - PROPERTY, PLANT AND EQUIPMENT</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PropertyPlantAndEquipmentComponentsOfPropertyPlantAndEquipmentDetail" roleURI="http://casella.com/role/PropertyPlantAndEquipmentComponentsOfPropertyPlantAndEquipmentDetail">
        <link:definition>2407402 - Disclosure - PROPERTY, PLANT AND EQUIPMENT - Components of Property, Plant and Equipment (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PropertyPlantAndEquipmentNarrativeDetail" roleURI="http://casella.com/role/PropertyPlantAndEquipmentNarrativeDetail">
        <link:definition>2407403 - Disclosure - PROPERTY, PLANT AND EQUIPMENT - Narrative (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PropertyPlantAndEquipmentTables" roleURI="http://casella.com/role/PropertyPlantAndEquipmentTables">
        <link:definition>2307301 - Disclosure - PROPERTY, PLANT AND EQUIPMENT (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="QuarterlyFinancialInformationUnaudited" roleURI="http://casella.com/role/QuarterlyFinancialInformationUnaudited">
        <link:definition>2120100 - Disclosure - QUARTERLY FINANCIAL INFORMATION (UNAUDITED)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="QuarterlyFinancialInformationUnauditedDetail" roleURI="http://casella.com/role/QuarterlyFinancialInformationUnauditedDetail">
        <link:definition>2420402 - Disclosure - QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="QuarterlyFinancialInformationUnauditedTables" roleURI="http://casella.com/role/QuarterlyFinancialInformationUnauditedTables">
        <link:definition>2320301 - Disclosure - QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RelatedPartyTransactions" roleURI="http://casella.com/role/RelatedPartyTransactions">
        <link:definition>2118100 - Disclosure - RELATED PARTY TRANSACTIONS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RelatedPartyTransactionsDetail" roleURI="http://casella.com/role/RelatedPartyTransactionsDetail">
        <link:definition>2418401 - Disclosure - RELATED PARTY TRANSACTIONS (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RestrictedAssets" roleURI="http://casella.com/role/RestrictedAssets">
        <link:definition>2106100 - Disclosure - RESTRICTED ASSETS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RestrictedAssetsDetail" roleURI="http://casella.com/role/RestrictedAssetsDetail">
        <link:definition>2406402 - Disclosure - RESTRICTED ASSETS (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RestrictedAssetsTables" roleURI="http://casella.com/role/RestrictedAssetsTables">
        <link:definition>2306301 - Disclosure - RESTRICTED  ASSETS (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RevenueRecognition" roleURI="http://casella.com/role/RevenueRecognition">
        <link:definition>2104100 - Disclosure - REVENUE RECOGNITION</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RevenueRecognitionDetails" roleURI="http://casella.com/role/RevenueRecognitionDetails">
        <link:definition>2404402 - Disclosure - REVENUE RECOGNITION (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RevenueRecognitionTables" roleURI="http://casella.com/role/RevenueRecognitionTables">
        <link:definition>2304301 - Disclosure - REVENUE RECOGNITION (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ScheduleIiValuationAccounts" roleURI="http://casella.com/role/ScheduleIiValuationAccounts">
        <link:definition>2121100 - Schedule - Schedule II - Valuation Accounts</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ScheduleIiValuationAccountsDetail" roleURI="http://casella.com/role/ScheduleIiValuationAccountsDetail">
        <link:definition>2421401 - Schedule - Schedule II - Valuation Accounts (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SegmentReporting" roleURI="http://casella.com/role/SegmentReporting">
        <link:definition>2119100 - Disclosure - SEGMENT REPORTING</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SegmentReportingSummaryOfFinancialInformationByReportableSegmentDetail" roleURI="http://casella.com/role/SegmentReportingSummaryOfFinancialInformationByReportableSegmentDetail">
        <link:definition>2419402 - Disclosure - SEGMENT REPORTING - Summary of Financial Information by Reportable Segment (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SegmentReportingSummaryOfRevenueAttributableToServicesProvidedByCompanyDetail" roleURI="http://casella.com/role/SegmentReportingSummaryOfRevenueAttributableToServicesProvidedByCompanyDetail">
        <link:definition>2419403 - Disclosure - SEGMENT REPORTING - Summary of Revenue Attributable to Services Provided by Company (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SegmentReportingTables" roleURI="http://casella.com/role/SegmentReportingTables">
        <link:definition>2319301 - Disclosure - SEGMENT REPORTING (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockholdersEquity" roleURI="http://casella.com/role/StockholdersEquity">
        <link:definition>2112100 - Disclosure - STOCKHOLDERS' EQUITY</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockholdersEquityAccumulatedOtherComprehensiveIncomeLossDetail" roleURI="http://casella.com/role/StockholdersEquityAccumulatedOtherComprehensiveIncomeLossDetail">
        <link:definition>2412405 - Disclosure - STOCKHOLDERS' EQUITY - Accumulated Other Comprehensive Income (Loss) (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockholdersEquityNarrativeDetail" roleURI="http://casella.com/role/StockholdersEquityNarrativeDetail">
        <link:definition>2412402 - Disclosure - STOCKHOLDERS' EQUITY - Narrative (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockholdersEquityReclassificationOutOfAccumulatedOtherComprehensiveIncomeLossDetail" roleURI="http://casella.com/role/StockholdersEquityReclassificationOutOfAccumulatedOtherComprehensiveIncomeLossDetail">
        <link:definition>2412406 - Disclosure - STOCKHOLDERS' EQUITY - Reclassification Out of Accumulated Other Comprehensive Income (Loss) (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockholdersEquitySummaryOfRestrictedStockRestrictedStockUnitAndPerformanceStockUnitActivityDetail" roleURI="http://casella.com/role/StockholdersEquitySummaryOfRestrictedStockRestrictedStockUnitAndPerformanceStockUnitActivityDetail">
        <link:definition>2412404 - Disclosure - STOCKHOLDERS' EQUITY - Summary of Restricted Stock, Restricted Stock Unit and Performance Stock Unit Activity (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockholdersEquitySummaryOfStockOptionActivityDetail" roleURI="http://casella.com/role/StockholdersEquitySummaryOfStockOptionActivityDetail">
        <link:definition>2412403 - Disclosure - STOCKHOLDERS' EQUITY - Summary of Stock Option Activity (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockholdersEquityTables" roleURI="http://casella.com/role/StockholdersEquityTables">
        <link:definition>2312301 - Disclosure - STOCKHOLDERS' EQUITY (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPolicies" roleURI="http://casella.com/role/SummaryOfSignificantAccountingPolicies">
        <link:definition>2103100 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesAssetImpairmentsDetail" roleURI="http://casella.com/role/SummaryOfSignificantAccountingPoliciesAssetImpairmentsDetail">
        <link:definition>2403408 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Asset Impairments (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesDefinedBenefitPensionPlanDetails" roleURI="http://casella.com/role/SummaryOfSignificantAccountingPoliciesDefinedBenefitPensionPlanDetails">
        <link:definition>2403409 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Defined Benefit Pension Plan (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesEstimatedUsefulLivesOfAssetsDetail" roleURI="http://casella.com/role/SummaryOfSignificantAccountingPoliciesEstimatedUsefulLivesOfAssetsDetail">
        <link:definition>2403402 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Estimated Useful Lives of Assets (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesGoodwillAndIntangibleAssetsDetail" roleURI="http://casella.com/role/SummaryOfSignificantAccountingPoliciesGoodwillAndIntangibleAssetsDetail">
        <link:definition>2403404 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Goodwill and Intangible Assets (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesInvestmentsInUnconsolidatedEntitiesDetail" roleURI="http://casella.com/role/SummaryOfSignificantAccountingPoliciesInvestmentsInUnconsolidatedEntitiesDetail">
        <link:definition>2403405 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Investments in Unconsolidated Entities (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesLandfillAccountingDetail" roleURI="http://casella.com/role/SummaryOfSignificantAccountingPoliciesLandfillAccountingDetail">
        <link:definition>2403403 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Landfill Accounting (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesRevenueRecognitionDetails" roleURI="http://casella.com/role/SummaryOfSignificantAccountingPoliciesRevenueRecognitionDetails">
        <link:definition>2403407 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES -Revenue Recognition (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesSelfInsuranceLiabilitiesAndRelatedCostsDetail" roleURI="http://casella.com/role/SummaryOfSignificantAccountingPoliciesSelfInsuranceLiabilitiesAndRelatedCostsDetail">
        <link:definition>2403406 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Self-Insurance Liabilities and Related Costs (Detail)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesTables" roleURI="http://casella.com/role/SummaryOfSignificantAccountingPoliciesTables">
        <link:definition>2303301 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
    </xsd:appinfo>
  </xsd:annotation>
  <xsd:element abstract="true" id="cwst_A2016IncentivePlanMember" name="A2016IncentivePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_A21ESettlementandWaterSystemConstructionFundingAgreementMember" name="A21ESettlementandWaterSystemConstructionFundingAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_AccrualForEnvironmentalLossContingenciesObligationsIncurred" name="AccrualForEnvironmentalLossContingenciesObligationsIncurred" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cwst_AdditionalRevolverCapacity" name="AdditionalRevolverCapacity" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="cwst_AdditionalSharesIssuedMaximumAttainmentLevel" name="AdditionalSharesIssuedMaximumAttainmentLevel" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_AgreenAndBgreenMember" name="AgreenAndBgreenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_AgreenEnergyLlcMember" name="AgreenEnergyLlcMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_AmendedAndRestatedNineteenNinetySevenEmployeeStockPurchasePlanMember" name="AmendedAndRestatedNineteenNinetySevenEmployeeStockPurchasePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_AncillaryServicesPeriod" name="AncillaryServicesPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_BgreenEnergyLlcMember" name="BgreenEnergyLlcMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_BusinessAcquisitionsProFormaOperatingIncomeLoss" name="BusinessAcquisitionsProFormaOperatingIncomeLoss" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="cwst_BusinessCombinationConsiderationTransferredNotesPayable" name="BusinessCombinationConsiderationTransferredNotesPayable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_ClosureAndPostClosureCostsMember" name="ClosureAndPostClosureCostsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_ClosureandPostClosureCostsIncurrencePeriod" name="ClosureandPostClosureCostsIncurrencePeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_CollectionBusinessMember" name="CollectionBusinessMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_CollectionMember" name="CollectionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_CommitmentAmountUnderEmploymentAgreement" name="CommitmentAmountUnderEmploymentAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cwst_CompleteDisposalCompanyIncMember" name="CompleteDisposalCompanyIncMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_ContractExtensionPeriod" name="ContractExtensionPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_ContractualObligationPaymentsPeriod" name="ContractualObligationPaymentsPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_CostMethodInvestmentOwnershipPercentage" name="CostMethodInvestmentOwnershipPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_CreditFacilityMember" name="CreditFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_CurrentStateDeferredBenefitLossCarryforwards" name="CurrentStateDeferredBenefitLossCarryforwards" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_CustomerSolutionsMember" name="CustomerSolutionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_DebtInstrumentCovenantComplianceNetLeverageRatio" name="DebtInstrumentCovenantComplianceNetLeverageRatio" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element id="cwst_DefinedContributionPlanEmployerMaximumContributionPerEmployeePerYearAmount" name="DefinedContributionPlanEmployerMaximumContributionPerEmployeePerYearAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cwst_DefinedContributionPlanMaximumEmployerMatchPerEmployeePerDollarContribution" name="DefinedContributionPlanMaximumEmployerMatchPerEmployeePerDollarContribution" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cwst_DepletionOfLandfillOperatingLeaseObligations" name="DepletionOfLandfillOperatingLeaseObligations" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cwst_DivestitureAcquisitionFinancingCosts" name="DivestitureAcquisitionFinancingCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_EasternRegionMember" name="EasternRegionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_EffectiveIncomeTaxRateReconciliationChangeinDeferredTaxAssetsValuationAllowanceIncludingFederalRateChangeAmount" name="EffectiveIncomeTaxRateReconciliationChangeinDeferredTaxAssetsValuationAllowanceIncludingFederalRateChangeAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="cwst_EffectiveIncomeTaxRateReconciliationDeductibleStockAwards" name="EffectiveIncomeTaxRateReconciliationDeductibleStockAwards" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="cwst_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOfficerCompensation" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOfficerCompensation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cwst_EmployeeServiceShareBasedCompensationTaxProvisionFromExerciseOfStockOptions" name="EmployeeServiceShareBasedCompensationTaxProvisionFromExerciseOfStockOptions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cwst_EmploymentContractsExecutiveOfficers" name="EmploymentContractsExecutiveOfficers" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="cwst_EnvironmentalRemediationExpenseIncludingNoncashCharges" name="EnvironmentalRemediationExpenseIncludingNoncashCharges" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cwst_ExpenseFromAcquisitionAndFinancingCostsAndOtherItems" name="ExpenseFromAcquisitionAndFinancingCostsAndOtherItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cwst_ExpenseFromAcquisitionAndFinancingCostsAndOtherItemsWriteOffOfDeferredCosts" name="ExpenseFromAcquisitionAndFinancingCostsAndOtherItemsWriteOffOfDeferredCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_FinanceAuthorityOfMaineSolidWasteDisposalRevenueBondsSeries2015R1Member" name="FinanceAuthorityOfMaineSolidWasteDisposalRevenueBondsSeries2015R1Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_FinanceAuthorityOfMaineSolidWasteDisposalRevenueBondsSeries2015R2Member" name="FinanceAuthorityOfMaineSolidWasteDisposalRevenueBondsSeries2015R2Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_FinanceAuthorityofMaineSolidWasteDisposalRevenueBondsSeries2005R3FAMEBonds2005R3Member" name="FinanceAuthorityofMaineSolidWasteDisposalRevenueBondsSeries2005R3FAMEBonds2005R3Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_FixedRateBondsMember" name="FixedRateBondsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_GreenerUIncMember" name="GreenerUIncMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_IncreaseDecreaseInAccruedExpensesContractLiabilitiesAndOtherLiabilities" name="IncreaseDecreaseInAccruedExpensesContractLiabilitiesAndOtherLiabilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cwst_InflationRate" name="InflationRate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_InitialTermOfExecutiveEmploymentAgreement" name="InitialTermOfExecutiveEmploymentAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_LandfillClosureSettlementChargeNet" name="LandfillClosureSettlementChargeNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_LandfillGasToEnergyMember" name="LandfillGasToEnergyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_LandfillOperatingLeaseMember" name="LandfillOperatingLeaseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_LandfillRevenueMember" name="LandfillRevenueMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_LandfillsMember" name="LandfillsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_LettersOfCreditFees" name="LettersOfCreditFees" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_LongTermRevenueBondSeriesTwoThousandThirteenDueTwoThousandThirtySixMember" name="LongTermRevenueBondSeriesTwoThousandThirteenDueTwoThousandThirtySixMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_MarketbasedPerformanceStockOptionsMember" name="MarketbasedPerformanceStockOptionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_MarketbasedPerformanceStockUnitsMember" name="MarketbasedPerformanceStockUnitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_MassachusettsDepartmentofEnvironmentalProtectionMADEPandCasellaWasteSystemsMember" name="MassachusettsDepartmentofEnvironmentalProtectionMADEPandCasellaWasteSystemsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_MaximumExposureSelfInsured" name="MaximumExposureSelfInsured" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cwst_MultiemployerPlansNumberofPlans" name="MultiemployerPlansNumberofPlans" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_NewEnglandTeamstersandTruckingIndustryPensionFundMember" name="NewEnglandTeamstersandTruckingIndustryPensionFundMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_NewHampshireBondsMember" name="NewHampshireBondsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_NewYorkBondsMember" name="NewYorkBondsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_NonCashExpenseFromAcquisitionActivitiesandOtherItems" name="NonCashExpenseFromAcquisitionActivitiesandOtherItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_NonEmployeeDirectorMember" name="NonEmployeeDirectorMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_NoncashLandfillClosureCharge" name="NoncashLandfillClosureCharge" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_NotesPayableMember" name="NotesPayableMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_NoticeofIntenttoSueundertheResourceConservationandRecoveryActMember" name="NoticeofIntenttoSueundertheResourceConservationandRecoveryActMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_NumberOfLeases" name="NumberOfLeases" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_NumberofLandfillOperationandManagementAgreementsEnteredInto" name="NumberofLandfillOperationandManagementAgreementsEnteredInto" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_NumberofStormWaterBasins" name="NumberofStormWaterBasins" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_OrganicsMember" name="OrganicsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_OtherAccruedLiabilitiesMember" name="OtherAccruedLiabilitiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_PaymentsForLandfillOperatingLease" name="PaymentsForLandfillOperatingLease" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="cwst_PercentageParticipationInOnsiteRemediationActivities" name="PercentageParticipationInOnsiteRemediationActivities" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cwst_PerformanceStockUnitMember" name="PerformanceStockUnitMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_PotsdamEnvironmentalLiabilityMember" name="PotsdamEnvironmentalLiabilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cwst_ProceedsfromInsuranceSettlementTransferedFromOperatingActivitiestoInvestingActivities" name="ProceedsfromInsuranceSettlementTransferedFromOperatingActivitiestoInvestingActivities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_PublicStockOfferingMember" name="PublicStockOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RecycleRewardsIncMember" name="RecycleRewardsIncMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RecyclingMember" name="RecyclingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RecyclingRevenuesMember" name="RecyclingRevenuesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RelatedPartyMember" name="RelatedPartyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RestrictedStockAndRestrictedStockUnitMember" name="RestrictedStockAndRestrictedStockUnitMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RestrictedStockAwardsMember" name="RestrictedStockAwardsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RestrictedStockRestrictedStockUnitsAndPerformanceStockUnitsMember" name="RestrictedStockRestrictedStockUnitsAndPerformanceStockUnitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cwst_RevenueBondSeriesTwoThousandFourteenRTwoDueTwoThousandFortyFourMember" name="RevenueBondSeriesTwoThousandFourteenRTwoDueTwoThousandFortyFourMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <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_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 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_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 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 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 id="cwst_TaxCutsandJobsActof2017ChangeinTaxRateChangeInValuationAllowanceIncomeTaxBenefitForContinuingOperations" name="TaxCutsandJobsActof2017ChangeinTaxRateChangeInValuationAllowanceIncomeTaxBenefitForContinuingOperations" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" 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 id="cwst_TaxCutsandJobsActof2017ChangeinTaxRateIncomeTaxExpenseBenefit" name="TaxCutsandJobsActof2017ChangeinTaxRateIncomeTaxExpenseBenefit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cwst_TaxCutsandJobsActof2017ChangeinTaxRateIndefiniteLivedDeferredTaxLiabilityIncomeTaxBenefit" name="TaxCutsandJobsActof2017ChangeinTaxRateIndefiniteLivedDeferredTaxLiabilityIncomeTaxBenefit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" 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_TransferBusinessMember" name="TransferBusinessMember" 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 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_VermontBondsMember" name="VermontBondsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <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>
