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  <xsd:element abstract="true" id="pagp_MesaToBasinPipelineReleaseMember" name="MesaToBasinPipelineReleaseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_NetGainLossOnForeignCurrencyRevaluation" name="NetGainLossOnForeignCurrencyRevaluation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_NetLongPositionOnCrudeOilDerivativeContractsMember" name="NetLongPositionOnCrudeOilDerivativeContractsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_NetProceedsFromRepaymentsOfHedgedInventoryFacility" name="NetProceedsFromRepaymentsOfHedgedInventoryFacility" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_NetShortPositionContractsRelatedToAnticipatedNetSalesOfInventoryMember" name="NetShortPositionContractsRelatedToAnticipatedNetSalesOfInventoryMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_NetShortPositionRelatedToAnticipatedSalesOfNaturalGasInventoryMember" name="NetShortPositionRelatedToAnticipatedSalesOfNaturalGasInventoryMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_NetShortTimeSpreadPositionOnAnticipatedCrudeOilLeaseGatheringPurchaseContractsMember" name="NetShortTimeSpreadPositionOnAnticipatedCrudeOilLeaseGatheringPurchaseContractsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_NonCorePipelineSegmentMember" name="NonCorePipelineSegmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_NoncontrollingInterestIncreaseFromSubsidiaryPreferredUnitIssuance" name="NoncontrollingInterestIncreaseFromSubsidiaryPreferredUnitIssuance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pagp_NumberOfAllegedRuleViolations" name="NumberOfAllegedRuleViolations" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="pagp_NumberOfDerivativesHeldWithCreditRiskRelatedContingentFeatures" name="NumberOfDerivativesHeldWithCreditRiskRelatedContingentFeatures" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="pagp_NumberOfEmployeesChargedInIndictment" name="NumberOfEmployeesChargedInIndictment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_NumberOfOccasionsFailedToCarryOutProgramAndProcedures" name="NumberOfOccasionsFailedToCarryOutProgramAndProcedures" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_OffsettingAssetsLiabilitiesLineItems" name="OffsettingAssetsLiabilitiesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_OffsettingAssetsLiabilitiesTable" name="OffsettingAssetsLiabilitiesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_OmnibusAgreementMember" name="OmnibusAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_OrganizationAndBasisOfPresentationLineItems" name="OrganizationAndBasisOfPresentationLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_OrganizationConsolidationAndPresentationOfFinancialStatementsTable" name="OrganizationConsolidationAndPresentationOfFinancialStatementsTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_OtherInventoryMember" name="OtherInventoryMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_OtherLongTermDebtMember" name="OtherLongTermDebtMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_OxyMember" name="OxyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_PaaGPLLCMember" name="PaaGPLLCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_PartnersCapitalAccountChangeInOwnershipInterest" name="PartnersCapitalAccountChangeInOwnershipInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pagp_PartnersCapitalAccountPublicSaleOfUnitsBySubsidiary" name="PartnersCapitalAccountPublicSaleOfUnitsBySubsidiary" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pagp_PartnersCapitalAccountUnitsIncreasefromSubsidiaryCommonUnitIssuance" name="PartnersCapitalAccountUnitsIncreasefromSubsidiaryCommonUnitIssuance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_PartnersCapitalAccountUnitsIncreasefromSubsidiaryPreferredUnitIssuance" name="PartnersCapitalAccountUnitsIncreasefromSubsidiaryPreferredUnitIssuance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_PartnersCapitalAndDistributionLineItems" name="PartnersCapitalAndDistributionLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_PartnersCapitalAndDistributionsTable" name="PartnersCapitalAndDistributionsTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_PartnersCapitalDeferredTaxAsset" name="PartnersCapitalDeferredTaxAsset" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pagp_PartnersCapitalUnitsOther" name="PartnersCapitalUnitsOther" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_PipelineAndHazardousMaterialsSafetyAdministrationMember" name="PipelineAndHazardousMaterialsSafetyAdministrationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_PipelineLossAllowanceOilLongCallOptionMember" name="PipelineLossAllowanceOilLongCallOptionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_PipelineTariffActivitiesTruckingAndRelatedRevenues" name="PipelineTariffActivitiesTruckingAndRelatedRevenues" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_PipelineTariffActivitiesTruckingAndRelatedRevenuesMember" name="PipelineTariffActivitiesTruckingAndRelatedRevenuesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_PlainsAapLPMember" name="PlainsAapLPMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_PlainsAllAmericanGPLLCMember" name="PlainsAllAmericanGPLLCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_PlainsAllAmericanPipelineLPMember" name="PlainsAllAmericanPipelineLPMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_ProceedsFromSubsidiaryIssuanceOfCommonLimitedPartnersUnits" name="ProceedsFromSubsidiaryIssuanceOfCommonLimitedPartnersUnits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="pagp_ProceedsFromSubsidiaryIssuanceOfPreferredLimitedPartnersUnits" name="ProceedsFromSubsidiaryIssuanceOfPreferredLimitedPartnersUnits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_PropaneMarineTerminalMember" name="PropaneMarineTerminalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_PublicUnitHoldersMember" name="PublicUnitHoldersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_RedRiverPipelineExtendingFromArdmoreToLongviewMember" name="RedRiverPipelineExtendingFromArdmoreToLongviewMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_RedRiverPipelineHewittSegmentMember" name="RedRiverPipelineHewittSegmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_RedRiverPipelineMember" name="RedRiverPipelineMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SLCPipelineLLCMember" name="SLCPipelineLLCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_SalesAndRelatedRevenues" name="SalesAndRelatedRevenues" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SalesAndRelatedRevenuesMember" name="SalesAndRelatedRevenuesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_ScheduleOfCalculationOfBasicAndDilutedNetIncomePerClassShareTable" name="ScheduleOfCalculationOfBasicAndDilutedNetIncomePerClassShareTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_ScheduleOfDebtInstrumentsTable" name="ScheduleOfDebtInstrumentsTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_ScheduleOfInventoryLinefillAndBaseGasAndLongTermInventoryTableTextBlock" name="ScheduleOfInventoryLinefillAndBaseGasAndLongTermInventoryTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SecuritiesLawClassActionLawsuitsMember" name="SecuritiesLawClassActionLawsuitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_SegmentAdjustedEBITDA" name="SegmentAdjustedEBITDA" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SegmentFacilitiesMember" name="SegmentFacilitiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SegmentSupplyAndLogisticsMember" name="SegmentSupplyAndLogisticsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SegmentTransportationMember" name="SegmentTransportationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SeniorNotesDueInJanuary2017At6.13PercentMember" name="SeniorNotesDueInJanuary2017At6.13PercentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SeniorSecuredHedgedInventoryFacilityMember" name="SeniorSecuredHedgedInventoryFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SeriesaPreferredUnitsMember" name="SeriesaPreferredUnitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SharesClassBMember" name="SharesClassBMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SharesClassCMember" name="SharesClassCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SharesClassMember" name="SharesClassMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_ShortButanePositionContractsRelatedToSubsequentSaleOfProductMember" name="ShortButanePositionContractsRelatedToSubsequentSaleOfProductMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_ShortPropanePositionContractsRelatedToSubsequentSaleOfProductMember" name="ShortPropanePositionContractsRelatedToSubsequentSaleOfProductMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_ShortWTIPositionContractsRelatedToSubsequentSaleOfProductMember" name="ShortWTIPositionContractsRelatedToSubsequentSaleOfProductMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_SimplificationAgreementMember" name="SimplificationAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_StandbyLettersOfCreditReceived" name="StandbyLettersOfCreditReceived" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="pagp_StorageTerminallingProcessingAndRelatedRevenues" name="StorageTerminallingProcessingAndRelatedRevenues" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pagp_SubsidiaryOfLimitedLiabilityCompanyOrLimitedPartnershipOwnershipInterestUnits" name="SubsidiaryOfLimitedLiabilityCompanyOrLimitedPartnershipOwnershipInterestUnits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_ThirdPartyEnvironmentalRecoveriesReceivedAndReceivable" name="ThirdPartyEnvironmentalRecoveriesReceivedAndReceivable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="pagp_TradeAccountsReceivableAndOtherReceivablesMember" name="TradeAccountsReceivableAndOtherReceivablesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_TradeAccountsReceivableNetDisclosureOfMaximumAgeOfBalancesPastScheduledInvoiceDate" name="TradeAccountsReceivableNetDisclosureOfMaximumAgeOfBalancesPastScheduledInvoiceDate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_UnderwrittenOfferingMember" name="UnderwrittenOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pagp_UnitholderDerivativeLawsuitsMember" name="UnitholderDerivativeLawsuitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pagp_VariationMarginPostedReturned" name="VariationMarginPostedReturned" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
</xsd:schema>
