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<!-- Modified on: 2/16/2022 4:48:27 PM --> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_PercentageOfOwnershipInterestSold" xlink:label="aci_PercentageOfOwnershipInterestSold"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_TermOfNotesReceivable" xlink:label="aci_TermOfNotesReceivable"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_NotesReceivablePeriodicPaymentReceivable" xlink:label="aci_NotesReceivablePeriodicPaymentReceivable"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NotesReceivableRelatedParties" xlink:label="us-gaap_NotesReceivableRelatedParties"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_EquityMethodInvestmentPercentOfOwnershipInterestAcquired" xlink:label="aci_EquityMethodInvestmentPercentOfOwnershipInterestAcquired"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage" xlink:label="us-gaap_EquityMethodInvestmentOwnershipPercentage"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates" xlink:label="us-gaap_ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GainLossOnSaleOfProperties" xlink:label="us-gaap_GainLossOnSaleOfProperties"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ProceedsFromDivestitureOfInterestInConsolidatedSubsidiaries" xlink:label="us-gaap_ProceedsFromDivestitureOfInterestInConsolidatedSubsidiaries"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal" xlink:label="us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="11" xlink:from="us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems" xlink:to="us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_DiscontinuedOperationAmountOfAdjustmentToProceedsFromDisposalDisbursements" xlink:label="aci_DiscontinuedOperationAmountOfAdjustmentToProceedsFromDisposalDisbursements"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="12" xlink:from="us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems" xlink:to="aci_DiscontinuedOperationAmountOfAdjustmentToProceedsFromDisposalDisbursements" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_NumberOfMiningCompanies" xlink:label="aci_NumberOfMiningCompanies"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="13" xlink:from="us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems" xlink:to="aci_NumberOfMiningCompanies" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BankruptcyClaimsAmountOfClaimsFiled" xlink:label="us-gaap_BankruptcyClaimsAmountOfClaimsFiled"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="14" xlink:from="us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems" xlink:to="us-gaap_BankruptcyClaimsAmountOfClaimsFiled" priority="1" use="optional"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:label="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubsegmentsAxis" xlink:label="us-gaap_SubsegmentsAxis"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:to="us-gaap_SubsegmentsAxis" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubsegmentsDomain" xlink:label="us-gaap_SubsegmentsDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_SubsegmentsAxis" xlink:to="us-gaap_SubsegmentsDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_CoalCreekMineMember" xlink:label="aci_CoalCreekMineMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_SubsegmentsDomain" xlink:to="aci_CoalCreekMineMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_ViperMineMember" xlink:label="aci_ViperMineMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_SubsegmentsDomain" xlink:to="aci_ViperMineMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_WestElkMineMember" xlink:label="aci_WestElkMineMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap_SubsegmentsDomain" xlink:to="aci_WestElkMineMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" xlink:label="srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:to="srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_EquityMethodInvesteeNameDomain" xlink:label="srt_EquityMethodInvesteeNameDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" xlink:to="srt_EquityMethodInvesteeNameDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_KnightHawkMember" xlink:label="aci_KnightHawkMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_EquityMethodInvesteeNameDomain" xlink:to="aci_KnightHawkMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_PriorEquityInvestmentMember" xlink:label="aci_PriorEquityInvestmentMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="srt_EquityMethodInvesteeNameDomain" xlink:to="aci_PriorEquityInvestmentMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentLineItems" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap_PropertyPlantAndEquipmentLineItems" xlink:to="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetImpairmentCharges" xlink:label="us-gaap_AssetImpairmentCharges"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SeveranceCosts1" xlink:label="us-gaap_SeveranceCosts1"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap_PropertyPlantAndEquipmentLineItems" xlink:to="us-gaap_SeveranceCosts1" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_NumberOfCorporateStaffAcceptedVoluntarySeparationPackage" xlink:label="aci_NumberOfCorporateStaffAcceptedVoluntarySeparationPackage"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap_PropertyPlantAndEquipmentLineItems" xlink:to="aci_NumberOfCorporateStaffAcceptedVoluntarySeparationPackage" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_AssetImpairmentChargesAndMineClosureCosts" xlink:label="aci_AssetImpairmentChargesAndMineClosureCosts"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap_PropertyPlantAndEquipmentLineItems" xlink:to="aci_AssetImpairmentChargesAndMineClosureCosts" priority="1" use="optional"/> |
| | </definitionLink> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsTable" xlink:label="us-gaap_ScheduleOfEquityMethodInvestmentsTable"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_EquityMethodInvesteeNameDomain" xlink:label="srt_EquityMethodInvesteeNameDomain"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_JointVenturePowderRiverBasinAndColoradoMiningOperationsMember" xlink:label="aci_JointVenturePowderRiverBasinAndColoradoMiningOperationsMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_EquityMethodInvesteeNameDomain" xlink:to="aci_JointVenturePowderRiverBasinAndColoradoMiningOperationsMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsLineItems" xlink:label="us-gaap_ScheduleOfEquityMethodInvestmentsLineItems"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap_ScheduleOfEquityMethodInvestmentsLineItems" xlink:to="us-gaap_ScheduleOfEquityMethodInvestmentsTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ProfessionalFees" xlink:label="us-gaap_ProfessionalFees"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfBusinessInsuranceRecoveriesTable" xlink:label="us-gaap_ScheduleOfBusinessInsuranceRecoveriesTable"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessInterruptionLossAxis" xlink:label="us-gaap_BusinessInterruptionLossAxis"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessInterruptionLossDomain" xlink:label="us-gaap_BusinessInterruptionLossDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_BusinessInterruptionLossAxis" xlink:to="us-gaap_BusinessInterruptionLossDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_MountainLaurelLongwallOperationsMember" xlink:label="aci_MountainLaurelLongwallOperationsMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_BusinessInterruptionLossDomain" xlink:to="aci_MountainLaurelLongwallOperationsMember" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessInterruptionLossLineItems" xlink:label="us-gaap_BusinessInterruptionLossLineItems"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GainOnBusinessInterruptionInsuranceRecovery" xlink:label="us-gaap_GainOnBusinessInterruptionInsuranceRecovery"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_BusinessInterruptionLossLineItems" xlink:to="us-gaap_GainOnBusinessInterruptionInsuranceRecovery" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_InsuranceRecoverySystemsNotRecoverable" xlink:label="aci_InsuranceRecoverySystemsNotRecoverable"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap_BusinessInterruptionLossLineItems" xlink:to="aci_InsuranceRecoverySystemsNotRecoverable" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_InsuranceRecoveryHydraulicShieldsNotRecoverable" xlink:label="aci_InsuranceRecoveryHydraulicShieldsNotRecoverable"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap_BusinessInterruptionLossLineItems" xlink:to="aci_InsuranceRecoveryHydraulicShieldsNotRecoverable" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InsuranceRecoveries" xlink:label="us-gaap_InsuranceRecoveries"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap_BusinessInterruptionLossLineItems" xlink:to="us-gaap_InsuranceRecoveries" priority="1" use="optional"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GainContingenciesTable" xlink:label="us-gaap_GainContingenciesTable"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_EquityMethodInvestmentPercentOfOwnershipInterestAcquired" xlink:label="aci_EquityMethodInvestmentPercentOfOwnershipInterestAcquired"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_DieselPurchasesMember" xlink:label="aci_DieselPurchasesMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_ConcentrationRiskTypeDomain" xlink:to="aci_DieselPurchasesMember" use="optional"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_AnnualPurchaseOfCommodityForOperations" xlink:label="aci_AnnualPurchaseOfCommodityForOperations"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeAveragePriceRiskOptionStrikePrice" xlink:label="us-gaap_DerivativeAveragePriceRiskOptionStrikePrice"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_ReportingYearAxis" xlink:label="aci_ReportingYearAxis"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_ReportingYearDomain" xlink:label="aci_ReportingYearDomain"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_YearOneMember" xlink:label="aci_YearOneMember"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_EquipmentFinancingArrangementMember" xlink:label="aci_EquipmentFinancingArrangementMember"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_TaxExemptBondsMember" xlink:label="aci_TaxExemptBondsMember"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_CappedCallTransactionsMember" xlink:label="aci_CappedCallTransactionsMember"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_DefinedBenefitPlansBenefitObligationExpensesAxis" xlink:label="aci_DefinedBenefitPlansBenefitObligationExpensesAxis"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_WorkersCompensationMember" xlink:label="aci_WorkersCompensationMember"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_AdditionalCollateralContingentAmountSelfInsured" xlink:label="aci_AdditionalCollateralContingentAmountSelfInsured"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_ThresholdForNumberOfDaysToPostAdditionalCollateral" xlink:label="aci_ThresholdForNumberOfDaysToPostAdditionalCollateral"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_DefinedBenefitPlansBenefitObligationExpensesAxis" xlink:label="aci_DefinedBenefitPlansBenefitObligationExpensesAxis"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_WorkersCompensationMember" xlink:label="aci_WorkersCompensationMember"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_OccupationalDiseaseMember" xlink:label="aci_OccupationalDiseaseMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="aci_WorkersCompensationMember" xlink:to="aci_OccupationalDiseaseMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_TraumaticInjuryClaimsAndAssessmentsMember" xlink:label="aci_TraumaticInjuryClaimsAndAssessmentsMember"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_AccruedWorkersCompensationLineItems" xlink:label="aci_AccruedWorkersCompensationLineItems"/> |
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| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="aci_AccruedWorkersCompensationLineItems" xlink:to="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherLaborRelatedExpenses" xlink:label="us-gaap_OtherLaborRelatedExpenses"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="6" xlink:from="aci_AccruedWorkersCompensationLineItems" xlink:to="us-gaap_OtherLaborRelatedExpenses" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_TotalWorkersCompensationExpense" xlink:label="aci_TotalWorkersCompensationExpense"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="7" xlink:from="aci_AccruedWorkersCompensationLineItems" xlink:to="aci_TotalWorkersCompensationExpense" priority="1" use="optional"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:label="us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_DefinedBenefitPlansBenefitObligationExpensesAxis" xlink:label="aci_DefinedBenefitPlansBenefitObligationExpensesAxis"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_DefinedBenefitPlansBenefitObligationExpensesDomain" xlink:label="aci_DefinedBenefitPlansBenefitObligationExpensesDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="aci_DefinedBenefitPlansBenefitObligationExpensesAxis" xlink:to="aci_DefinedBenefitPlansBenefitObligationExpensesDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_OccupationalDiseaseMember" xlink:label="aci_OccupationalDiseaseMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="aci_DefinedBenefitPlansBenefitObligationExpensesDomain" xlink:to="aci_OccupationalDiseaseMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_MeasurementInputTypeAxis" xlink:label="us-gaap_MeasurementInputTypeAxis"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_MeasurementInputTypeDomain" xlink:label="us-gaap_MeasurementInputTypeDomain"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_MeasurementInputDiscountRateMember" xlink:label="us-gaap_MeasurementInputDiscountRateMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="us-gaap_MeasurementInputDiscountRateMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:label="us-gaap_DefinedBenefitPlanDisclosureLineItems"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:to="us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_SelfInsuranceReserveRollForward" xlink:label="aci_SelfInsuranceReserveRollForward"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:to="aci_SelfInsuranceReserveRollForward" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SelfInsuranceReserveNoncurrent" xlink:label="us-gaap_SelfInsuranceReserveNoncurrent"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="aci_SelfInsuranceReserveRollForward" xlink:to="us-gaap_SelfInsuranceReserveNoncurrent" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DefinedBenefitPlanServiceCost" xlink:label="us-gaap_DefinedBenefitPlanServiceCost"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="aci_SelfInsuranceReserveRollForward" xlink:to="us-gaap_DefinedBenefitPlanServiceCost" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DefinedBenefitPlanInterestCost" xlink:label="us-gaap_DefinedBenefitPlanInterestCost"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="aci_SelfInsuranceReserveRollForward" xlink:to="us-gaap_DefinedBenefitPlanInterestCost" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DefinedBenefitPlanActuarialGainLoss" xlink:label="us-gaap_DefinedBenefitPlanActuarialGainLoss"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="aci_SelfInsuranceReserveRollForward" xlink:to="us-gaap_DefinedBenefitPlanActuarialGainLoss" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_DefinedBenefitPlanBenefitsPaidAndAdministrativeExpenses" xlink:label="aci_DefinedBenefitPlanBenefitsPaidAndAdministrativeExpenses"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="aci_SelfInsuranceReserveRollForward" xlink:to="aci_DefinedBenefitPlanBenefitsPaidAndAdministrativeExpenses" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtInstrumentMeasurementInput" xlink:label="us-gaap_DebtInstrumentMeasurementInput"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:to="us-gaap_DebtInstrumentMeasurementInput" priority="1" use="optional"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:label="us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_DefinedBenefitPlansBenefitObligationExpensesAxis" xlink:label="aci_DefinedBenefitPlansBenefitObligationExpensesAxis"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_DefinedBenefitPlansBenefitObligationExpensesDomain" xlink:label="aci_DefinedBenefitPlansBenefitObligationExpensesDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="aci_DefinedBenefitPlansBenefitObligationExpensesAxis" xlink:to="aci_DefinedBenefitPlansBenefitObligationExpensesDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_OccupationalDiseaseMember" xlink:label="aci_OccupationalDiseaseMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="aci_DefinedBenefitPlansBenefitObligationExpensesDomain" xlink:to="aci_OccupationalDiseaseMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_WorkersCompensationMember" xlink:label="aci_WorkersCompensationMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="aci_DefinedBenefitPlansBenefitObligationExpensesDomain" xlink:to="aci_WorkersCompensationMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_AccruedWorkersCompensationLineItems" xlink:label="aci_AccruedWorkersCompensationLineItems"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="aci_AccruedWorkersCompensationLineItems" xlink:to="us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SelfInsuranceReserveNoncurrent" xlink:label="us-gaap_SelfInsuranceReserveNoncurrent"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_WorkersCompensationLiabilityCurrentAndNoncurrent" xlink:label="us-gaap_WorkersCompensationLiabilityCurrentAndNoncurrent"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="aci_AccruedWorkersCompensationLineItems" xlink:to="us-gaap_WorkersCompensationLiabilityCurrentAndNoncurrent" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_WorkersCompensationLiabilityCurrent" xlink:label="us-gaap_WorkersCompensationLiabilityCurrent"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="aci_AccruedWorkersCompensationLineItems" xlink:to="us-gaap_WorkersCompensationLiabilityCurrent" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_WorkersCompensationLiabilityNoncurrent" xlink:label="us-gaap_WorkersCompensationLiabilityNoncurrent"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="aci_AccruedWorkersCompensationLineItems" xlink:to="us-gaap_WorkersCompensationLiabilityNoncurrent" priority="1" use="optional"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_WorkersCompensationObligationMember" xlink:label="aci_WorkersCompensationObligationMember"/> |
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| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_ConcentrationRiskTypeDomain" xlink:to="aci_DomesticAndForeignSteelProducersMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ConcentrationRiskLineItems" xlink:label="us-gaap_ConcentrationRiskLineItems"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="us-gaap_ConcentrationRiskTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ReceivablesNetCurrent" xlink:label="us-gaap_ReceivablesNetCurrent"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="us-gaap_ReceivablesNetCurrent" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_AccountsReceivablesPercentageOfTotalTrade" xlink:label="aci_AccountsReceivablesPercentageOfTotalTrade"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="aci_AccountsReceivablesPercentageOfTotalTrade" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="us-gaap_AccountsReceivableNetCurrent"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="us-gaap_AccountsReceivableNetCurrent" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_PercentageOfAccountsReceivableNetCurrent" xlink:label="aci_PercentageOfAccountsReceivableNetCurrent"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="aci_PercentageOfAccountsReceivableNetCurrent" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_GoodsSoldDuringYear" xlink:label="aci_GoodsSoldDuringYear"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="6" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="aci_GoodsSoldDuringYear" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_PercentageOfGoodsSoldUnderLongTermContract" xlink:label="aci_PercentageOfGoodsSoldUnderLongTermContract"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="7" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="aci_PercentageOfGoodsSoldUnderLongTermContract" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_PercentageCompanyRevenue" xlink:label="aci_PercentageCompanyRevenue"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="8" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="aci_PercentageCompanyRevenue" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_LongTermContractsLifeTermMinimum" xlink:label="aci_LongTermContractsLifeTermMinimum"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="9" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="aci_LongTermContractsLifeTermMinimum" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_LongTermContractsLifeTermMaximum" xlink:label="aci_LongTermContractsLifeTermMaximum"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="10" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="aci_LongTermContractsLifeTermMaximum" priority="1" use="optional"/> |
| | </definitionLink> |
| <definitionLink xlink:role="http://www.archcoal.com/role/DisclosureRiskConcentrationsScheduleOfForeignRevenuesDetails" xlink:type="extended" xlink:title="42402 - Disclosure - Risk Concentrations (Schedule of Foreign Revenues) (Details)" xmlns="http://www.xbrl.org/2003/linkbase"> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ConcentrationRiskTable" xlink:label="us-gaap_ConcentrationRiskTable"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_StatementGeographicalAxis" xlink:label="srt_StatementGeographicalAxis"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap_ConcentrationRiskTable" xlink:to="srt_StatementGeographicalAxis" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="srt_SegmentGeographicalDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_StatementGeographicalAxis" xlink:to="srt_SegmentGeographicalDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_EuropeMember" xlink:label="srt_EuropeMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_SegmentGeographicalDomain" xlink:to="srt_EuropeMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_AsiaMember" xlink:label="srt_AsiaMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="srt_SegmentGeographicalDomain" xlink:to="srt_AsiaMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_CentralAndSouthAmericaMember" xlink:label="aci_CentralAndSouthAmericaMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="srt_SegmentGeographicalDomain" xlink:to="aci_CentralAndSouthAmericaMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_AfricaMember" xlink:label="srt_AfricaMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="srt_SegmentGeographicalDomain" xlink:to="srt_AfricaMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ProductOrServiceAxis" xlink:label="srt_ProductOrServiceAxis"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap_ConcentrationRiskTable" xlink:to="srt_ProductOrServiceAxis" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="srt_ProductsAndServicesDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_ProductOrServiceAxis" xlink:to="srt_ProductsAndServicesDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_SeaborneRevenueMember" xlink:label="aci_SeaborneRevenueMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_ProductsAndServicesDomain" xlink:to="aci_SeaborneRevenueMember" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ConcentrationRiskLineItems" xlink:label="us-gaap_ConcentrationRiskLineItems"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="us-gaap_ConcentrationRiskTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" priority="1" use="optional"/> |
| | </definitionLink> |
| <definitionLink xlink:role="http://www.archcoal.com/role/DisclosureRevenueRecognitionScheduleOfRevenuesDetails" xlink:type="extended" xlink:title="42501 - Disclosure - Revenue Recognition (Schedule of Revenues) (Details)" xmlns="http://www.xbrl.org/2003/linkbase"> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DisaggregationOfRevenueTable" xlink:label="us-gaap_DisaggregationOfRevenueTable"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsAxis" xlink:label="srt_ConsolidationItemsAxis"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap_DisaggregationOfRevenueTable" xlink:to="srt_ConsolidationItemsAxis" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="srt_ConsolidationItemsDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_ConsolidationItemsAxis" xlink:to="srt_ConsolidationItemsDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingSegmentsMember" xlink:label="us-gaap_OperatingSegmentsMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_ConsolidationItemsDomain" xlink:to="us-gaap_OperatingSegmentsMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IntersegmentEliminationMember" xlink:label="us-gaap_IntersegmentEliminationMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="srt_ConsolidationItemsDomain" xlink:to="us-gaap_IntersegmentEliminationMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="us-gaap_StatementBusinessSegmentsAxis"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap_DisaggregationOfRevenueTable" xlink:to="us-gaap_StatementBusinessSegmentsAxis" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain" xlink:label="us-gaap_SegmentDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_StatementBusinessSegmentsAxis" xlink:to="us-gaap_SegmentDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_MetallurgicalSegmentMember" xlink:label="aci_MetallurgicalSegmentMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_SegmentDomain" xlink:to="aci_MetallurgicalSegmentMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_ThermalSegmentMember" xlink:label="aci_ThermalSegmentMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_SegmentDomain" xlink:to="aci_ThermalSegmentMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_StatementGeographicalAxis" xlink:label="srt_StatementGeographicalAxis"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="3" xlink:from="us-gaap_DisaggregationOfRevenueTable" xlink:to="srt_StatementGeographicalAxis" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="srt_SegmentGeographicalDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_StatementGeographicalAxis" xlink:to="srt_SegmentGeographicalDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_NorthAmericaMember" xlink:label="srt_NorthAmericaMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_SegmentGeographicalDomain" xlink:to="srt_NorthAmericaMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_ForeignCountriesMember" xlink:label="aci_ForeignCountriesMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="srt_SegmentGeographicalDomain" xlink:to="aci_ForeignCountriesMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DisaggregationOfRevenueLineItems" xlink:label="us-gaap_DisaggregationOfRevenueLineItems"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap_DisaggregationOfRevenueLineItems" xlink:to="us-gaap_DisaggregationOfRevenueTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_DisaggregationOfRevenueLineItems" xlink:to="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" priority="1" use="optional"/> |
| | </definitionLink> |
| <definitionLink xlink:role="http://www.archcoal.com/role/DisclosureRevenueRecognitionNarrativeDetails" xlink:type="extended" xlink:title="42502 - Disclosure - Revenue Recognition (Narrative) (Details)" xmlns="http://www.xbrl.org/2003/linkbase"> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ProductOrServiceAxis" xlink:label="srt_ProductOrServiceAxis"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" xlink:to="srt_ProductOrServiceAxis" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="srt_ProductsAndServicesDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_ProductOrServiceAxis" xlink:to="srt_ProductsAndServicesDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PublicUtilitiesInventoryCoalMember" xlink:label="us-gaap_PublicUtilitiesInventoryCoalMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_ProductsAndServicesDomain" xlink:to="us-gaap_PublicUtilitiesInventoryCoalMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" xlink:to="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" xlink:to="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_RevenueRemainingPerformanceObligationMass" xlink:label="aci_RevenueRemainingPerformanceObligationMass"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" xlink:to="aci_RevenueRemainingPerformanceObligationMass" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_RevenueRemainingPerformanceObligationFixedPriceVolume" xlink:label="aci_RevenueRemainingPerformanceObligationFixedPriceVolume"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" xlink:to="aci_RevenueRemainingPerformanceObligationFixedPriceVolume" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_RevenueRemainingPerformanceObligationVariablePriceVolume" xlink:label="aci_RevenueRemainingPerformanceObligationVariablePriceVolume"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" xlink:to="aci_RevenueRemainingPerformanceObligationVariablePriceVolume" priority="1" use="optional"/> |
| | </definitionLink> |
| <definitionLink xlink:role="http://www.archcoal.com/role/DisclosureRevenueRecognitionNarrativeDefaultDetails" xlink:type="extended" xlink:title="42502 - Disclosure - Revenue Recognition (Narrative) Default (Details)" xmlns="http://www.xbrl.org/2003/linkbase"> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ProductOrServiceAxis" xlink:label="srt_ProductOrServiceAxis"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" xlink:to="srt_ProductOrServiceAxis" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="srt_ProductsAndServicesDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_ProductOrServiceAxis" xlink:to="srt_ProductsAndServicesDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PublicUtilitiesInventoryCoalMember" xlink:label="us-gaap_PublicUtilitiesInventoryCoalMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_ProductsAndServicesDomain" xlink:to="us-gaap_PublicUtilitiesInventoryCoalMember" use="optional"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_RevenueRemainingPerformanceObligationMass" xlink:label="aci_RevenueRemainingPerformanceObligationMass"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_RevenueRemainingPerformanceObligationFixedPriceVolume" xlink:label="aci_RevenueRemainingPerformanceObligationFixedPriceVolume"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_RevenueRemainingPerformanceObligationVariablePriceVolume" xlink:label="aci_RevenueRemainingPerformanceObligationVariablePriceVolume"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" xlink:to="aci_RevenueRemainingPerformanceObligationVariablePriceVolume" priority="1" use="optional"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingSegmentsMember" xlink:label="us-gaap_OperatingSegmentsMember"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="us-gaap_StatementBusinessSegmentsAxis"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentDomain" xlink:label="us-gaap_SegmentDomain"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_MetallurgicalSegmentMember" xlink:label="aci_MetallurgicalSegmentMember"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_ThermalSegmentMember" xlink:label="aci_ThermalSegmentMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_SegmentDomain" xlink:to="aci_ThermalSegmentMember" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="us-gaap_SegmentReportingInformationLineItems"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NumberOfReportableSegments" xlink:label="us-gaap_NumberOfReportableSegments"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_NumberOfRemainingActiveThermalMines" xlink:label="aci_NumberOfRemainingActiveThermalMines"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="aci_NumberOfRemainingActiveThermalMines" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_NumberOfDistinctLinesOfBusiness" xlink:label="aci_NumberOfDistinctLinesOfBusiness"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="aci_NumberOfDistinctLinesOfBusiness" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_AdjustedEBITDA" xlink:label="aci_AdjustedEBITDA"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="6" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="aci_AdjustedEBITDA" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="us-gaap_DepreciationDepletionAndAmortization"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetRetirementObligationAccretionExpense" xlink:label="us-gaap_AssetRetirementObligationAccretionExpense"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="8" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="us-gaap_AssetRetirementObligationAccretionExpense" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_Assets" xlink:label="us-gaap_Assets"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="10" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" priority="1" use="optional"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis" xlink:label="us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:label="us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis" xlink:to="us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_DalTexAndBriarBranchPropertiesMember" xlink:label="aci_DalTexAndBriarBranchPropertiesMember"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:to="aci_DalTexAndBriarBranchPropertiesMember" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="us-gaap_SegmentReportingInformationLineItems"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss"/> |
| | <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="us-gaap_NetIncomeLoss" priority="1" use="optional"/> |
| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="us-gaap_IncomeTaxExpenseBenefit"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InterestIncomeExpenseNonoperatingNet" xlink:label="us-gaap_InterestIncomeExpenseNonoperatingNet"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_OperatingIncomeExpenseRelatedToJointVenture" xlink:label="aci_OperatingIncomeExpenseRelatedToJointVenture"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_AssetImpairmentChargesAndMineClosureCosts" xlink:label="aci_AssetImpairmentChargesAndMineClosureCosts"/> |
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| | <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GainOnBusinessInterruptionInsuranceRecovery" xlink:label="us-gaap_GainOnBusinessInterruptionInsuranceRecovery"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_AdjustedEBITDA" xlink:label="aci_AdjustedEBITDA"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_EBITDFromIdledOrOtherwiseDisposedOperations" xlink:label="aci_EBITDFromIdledOrOtherwiseDisposedOperations"/> |
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| | <loc xlink:type="locator" xlink:href="arch-20211231.xsd#aci_SegmentAdjustedEBITDFromCoalOperations" xlink:label="aci_SegmentAdjustedEBITDFromCoalOperations"/> |
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