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  <xs:element id="pagp_CounterpartyDeficiencies" abstract="false" name="CounterpartyDeficiencies" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_SeniorUnsecuredRevolvingCreditFacilityMember" abstract="true" name="SeniorUnsecuredRevolvingCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_ContractWithCustomerContractualRightsOfOffsetWithCounterparties" abstract="false" name="ContractWithCustomerContractualRightsOfOffsetWithCounterparties" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_LongTermInventoryCostingAdjustments" abstract="false" name="LongTermInventoryCostingAdjustments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_PlainsAAPLPMember" abstract="true" name="PlainsAAPLPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_PartnersCapitalDeferredTaxAsset" abstract="false" name="PartnersCapitalDeferredTaxAsset" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_EstimatedSizeOfReleaseToReachBodyOfWater" abstract="false" name="EstimatedSizeOfReleaseToReachBodyOfWater" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:volumeItemType"/>
  <xs:element id="pagp_EstimatedSizeOfRelease" abstract="false" name="EstimatedSizeOfRelease" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:volumeItemType"/>
  <xs:element id="pagp_AOCIOtherIncludingPortionAttributabletoNoncontrollingInterestMember" abstract="true" name="AOCIOtherIncludingPortionAttributabletoNoncontrollingInterestMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_UnitholderDerivativeLawsuitsMember" abstract="true" name="UnitholderDerivativeLawsuitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_MaintenanceCapitalExpenditures" abstract="false" name="MaintenanceCapitalExpenditures" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_GainOnSalesOfLinefill" abstract="false" name="GainOnSalesOfLinefill" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_RedRiverPipelineCompanyLLCMember" abstract="true" name="RedRiverPipelineCompanyLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_IndictmentNumberofMisdemeanorChargesGuiltyVerdict" abstract="false" name="IndictmentNumberofMisdemeanorChargesGuiltyVerdict" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pagp_SharesClassCMember" abstract="true" name="SharesClassCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_TradeAccountsReceivableNetDisclosureOfMaximumAgeOfBalancesPastInvoiceDate" abstract="false" name="TradeAccountsReceivableNetDisclosureOfMaximumAgeOfBalancesPastInvoiceDate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pagp_PipelineRevenuesSupportedByMinimumVolumeCommitmentsAndLongTermCapacityAgreementsMember" abstract="true" name="PipelineRevenuesSupportedByMinimumVolumeCommitmentsAndLongTermCapacityAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_PartnersCapitalAndDistributionsTable" abstract="true" name="PartnersCapitalAndDistributionsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pagp_PlainsAllAmericanPipelineLPMember" abstract="true" name="PlainsAllAmericanPipelineLPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_DepreciationAndAmortizationOfUnconsolidatedEntities" abstract="false" name="DepreciationAndAmortizationOfUnconsolidatedEntities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_OtherDebtMember" abstract="true" name="OtherDebtMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_OffsettingAssetsLiabilitiesTable" abstract="true" name="OffsettingAssetsLiabilitiesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pagp_PartnersCapitalAccountSharesCancellationOfShares" abstract="false" name="PartnersCapitalAccountSharesCancellationOfShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pagp_VariationMarginPostedReturned" abstract="false" name="VariationMarginPostedReturned" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_LimitedPartnersCapitalAccountSharesIssuedRedeemedinRedemptionRightExercises" abstract="false" name="LimitedPartnersCapitalAccountSharesIssuedRedeemedinRedemptionRightExercises" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pagp_OtherLongTermDebtMember" abstract="true" name="OtherLongTermDebtMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_PropaneContractsRelatedToSubsequentSaleOfProductMember" abstract="true" name="PropaneContractsRelatedToSubsequentSaleOfProductMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_IndictmentNumberofFelonyDischargesGuiltyVerdict" abstract="false" name="IndictmentNumberofFelonyDischargesGuiltyVerdict" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pagp_SeniorNotesDueInJune2022At365PercentMember" abstract="true" name="SeniorNotesDueInJune2022At365PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_NetCashPaidReceivedForTerminatedHedgingInstruments" abstract="false" name="NetCashPaidReceivedForTerminatedHedgingInstruments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_ScheduleOfCalculationOfBasicAndDilutedNetIncomePerClassShareTable" abstract="true" name="ScheduleOfCalculationOfBasicAndDilutedNetIncomePerClassShareTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pagp_IndictmentNumberofMisdemeanorChargesNotGuiltyVerdictStrictLiabilityAnimalTakingsCount" abstract="false" name="IndictmentNumberofMisdemeanorChargesNotGuiltyVerdictStrictLiabilityAnimalTakingsCount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pagp_CondensateContractsRelatedToSubsequentSaleOfProductMemberMember" abstract="true" name="CondensateContractsRelatedToSubsequentSaleOfProductMemberMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_InventoryWeightedAveragePricePerUnitLinefill" abstract="false" name="InventoryWeightedAveragePricePerUnitLinefill" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="srt-types:perUnitItemType"/>
  <xs:element id="pagp_InventoryVolumesNoncurrent" abstract="false" name="InventoryVolumesNoncurrent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:volumeItemType"/>
  <xs:element id="pagp_Linefill" abstract="false" name="Linefill" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_DeficienciesUnderMinimumVolumeCommitmentsNet" abstract="false" name="DeficienciesUnderMinimumVolumeCommitmentsNet" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_OrganizationAndBasisOfPresentationLineItems" abstract="true" name="OrganizationAndBasisOfPresentationLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pagp_NaturalGasContractsMember" abstract="true" name="NaturalGasContractsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pagp_GainsLossesFromDerivativeActivitiesAndInventoryValuationAdjustments" abstract="false" name="GainsLossesFromDerivativeActivitiesAndInventoryValuationAdjustments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_AAPManagementUnitsMember" abstract="true" name="AAPManagementUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
