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  <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_SegmentFacilitiesMember" abstract="true" name="SegmentFacilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_NGLAndNaturalGasProcessingAndFractionationMember" abstract="true" name="NGLAndNaturalGasProcessingAndFractionationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_InventoryVolumesCurrent" abstract="false" name="InventoryVolumesCurrent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:volumeItemType"/>
  <xs:element id="pagp_LongPositionOnNaturalGasContractsMember" abstract="true" name="LongPositionOnNaturalGasContractsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LimitedPartnersCapitalSharesIssuedFromConversion" abstract="false" name="LimitedPartnersCapitalSharesIssuedFromConversion" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pagp_PartnersCapitalUnitsOther" abstract="false" name="PartnersCapitalUnitsOther" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pagp_ScheduleOfCalculationOfBasicAndDilutedNetIncomePerClassShareTable" abstract="true" name="ScheduleOfCalculationOfBasicAndDilutedNetIncomePerClassShareTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pagp_ProceedsFromContributionsFromNoncontrollingInterests" abstract="false" name="ProceedsFromContributionsFromNoncontrollingInterests" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_NetProceedsFromRepaymentsOfHedgedInventoryFacility" abstract="false" name="NetProceedsFromRepaymentsOfHedgedInventoryFacility" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_PlainsAllAmericanPipelineLPMember" abstract="true" name="PlainsAllAmericanPipelineLPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SharesClassCMember" abstract="true" name="SharesClassCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ThirdPartyEnvironmentalRecoveriesReceivedAndReceivable" abstract="false" name="ThirdPartyEnvironmentalRecoveriesReceivedAndReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_CrudeOilNGLAndOtherTerminallingAndStorageMember" abstract="true" name="CrudeOilNGLAndOtherTerminallingAndStorageMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_InventoryCurrentAndNoncurrent" abstract="false" name="InventoryCurrentAndNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_LineOfCreditAndCommercialPaperMember" abstract="true" name="LineOfCreditAndCommercialPaperMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_NetShortPositionContractsRelatedToAnticipatedNetSalesOfInventoryMember" abstract="true" name="NetShortPositionContractsRelatedToAnticipatedNetSalesOfInventoryMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_TariffActivitiesMember" abstract="true" name="TariffActivitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_InitialMargin" abstract="false" name="InitialMargin" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_IndictmentNumberofMisdemeanorChargesGuiltyVerdictReportingCount" abstract="false" name="IndictmentNumberofMisdemeanorChargesGuiltyVerdictReportingCount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pagp_CounterpartyDeficienciesUnbilledAndUncollected" abstract="false" name="CounterpartyDeficienciesUnbilledAndUncollected" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_PipelineRevenuesSupportedByMinimumVolumeCommitmentsAndLongTermCapacityAgreementsMember" abstract="true" name="PipelineRevenuesSupportedByMinimumVolumeCommitmentsAndLongTermCapacityAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_MinimumVolumeCommitmentAgreementsMember" abstract="true" name="MinimumVolumeCommitmentAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ShortButanePositionContractsRelatedToSubsequentSaleOfProductMember" abstract="true" name="ShortButanePositionContractsRelatedToSubsequentSaleOfProductMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ConsentDecreeCompensationForInjuriesToDestructionOfLossOfUseOfNaturalResourcesMember" abstract="true" name="ConsentDecreeCompensationForInjuriesToDestructionOfLossOfUseOfNaturalResourcesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_OtherInventoryMember" abstract="true" name="OtherInventoryMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_TariffActivitiesCrudeOilPipelinesMember" abstract="true" name="TariffActivitiesCrudeOilPipelinesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_OtherDebtMember" abstract="true" name="OtherDebtMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_IndictmentNumberofMisdemeanorChargesNotGuiltyVerdictStrictLiabilityAnimalTakingsCount" abstract="false" name="IndictmentNumberofMisdemeanorChargesNotGuiltyVerdictStrictLiabilityAnimalTakingsCount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pagp_IndictmentNumberofMisdemeanorChargesGuiltyVerdictStrictLiabilityDischargeCount" abstract="false" name="IndictmentNumberofMisdemeanorChargesGuiltyVerdictStrictLiabilityDischargeCount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pagp_RailLoadAndUnloadMember" abstract="true" name="RailLoadAndUnloadMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_InventoryLinefillAndBaseGasAndLongTermInventoryDisclosureTextBlock" abstract="false" name="InventoryLinefillAndBaseGasAndLongTermInventoryDisclosureTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="pagp_ContractWithCustomerAssetAndLiabilityTable" abstract="true" name="ContractWithCustomerAssetAndLiabilityTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pagp_EstimatedSizeOfReleaseToReachBodyOfWater" abstract="false" name="EstimatedSizeOfReleaseToReachBodyOfWater" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:volumeItemType"/>
  <xs:element id="pagp_CommonUnitsMember" abstract="true" name="CommonUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum: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_SegmentAdjustedEBITDA" abstract="false" name="SegmentAdjustedEBITDA" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_OffsettingAssetsLiabilitiesLineItems" abstract="true" name="OffsettingAssetsLiabilitiesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pagp_SharesClassAMember" abstract="true" name="SharesClassAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LongPositionOnFuelGasRequirementsContractsMember" abstract="true" name="LongPositionOnFuelGasRequirementsContractsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_NetLongPositionOnCrudeOilDerivativeContractsMember" abstract="true" name="NetLongPositionOnCrudeOilDerivativeContractsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_EliminationsAndReconcilingItemsMember" abstract="true" name="EliminationsAndReconcilingItemsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SegmentTransportationMember" abstract="true" name="SegmentTransportationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_PlainsAapLPMember" abstract="true" name="PlainsAapLPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum: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_PartnersCapitalAndDistributionsTable" abstract="true" name="PartnersCapitalAndDistributionsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pagp_GOZoneTermLoansMember" abstract="true" name="GOZoneTermLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_IndictmentInCaliforniaSuperiorCourtSantaBarbaraCountyMember" abstract="true" name="IndictmentInCaliforniaSuperiorCourtSantaBarbaraCountyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ForeignExchangeForwardContractsThatExchangeCanadianDollarsForUSDollarsAtAverageRateDisclosedMaturingIn2021Member" abstract="true" name="ForeignExchangeForwardContractsThatExchangeCanadianDollarsForUSDollarsAtAverageRateDisclosedMaturingIn2021Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LimitedPartnersCapitalAccountSharesIssuedExchangedinExchangeRightExercises" abstract="false" name="LimitedPartnersCapitalAccountSharesIssuedExchangedinExchangeRightExercises" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pagp_AAPUnitsMember" abstract="true" name="AAPUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_UnitholderDerivativeLawsuitsMember" abstract="true" name="UnitholderDerivativeLawsuitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_PartnersCapitalAndDistributionLineItems" abstract="true" name="PartnersCapitalAndDistributionLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pagp_TruckingMember" abstract="true" name="TruckingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
</xs:schema>
