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  <xs:element name="CurrentEmployeeAgeOfEligibilityByDecember2010ToReceiveRetireeMedicalBenefits" id="mdu_CurrentEmployeeAgeOfEligibilityByDecember2010ToReceiveRetireeMedicalBenefits" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
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  <xs:element name="CurrentEmployeeAgeOfEligibilityAfterDecember2010ToReceiveRetireeMedicalBenefits" id="mdu_CurrentEmployeeAgeOfEligibilityAfterDecember2010ToReceiveRetireeMedicalBenefits" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
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  <xs:element name="AmountOfCompensatoryDamagesInDemandNotice" id="mdu_AmountOfCompensatoryDamagesInDemandNotice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
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  <xs:element name="NumberOfPurchaseAndSaleAgreementsIndemnifiedByCompany" id="mdu_NumberOfPurchaseAndSaleAgreementsIndemnifiedByCompany" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
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  <xs:element name="USTreasurySecuritiesFairValueDisclosure" id="mdu_USTreasurySecuritiesFairValueDisclosure" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xs:element name="PercentageInvestmentInCommonStockOfMidCapCompanies" id="mdu_PercentageInvestmentInCommonStockOfMidCapCompanies" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
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  <xs:element name="PercentageInvestmentInCashAndCashEquivalents" id="mdu_PercentageInvestmentInCashAndCashEquivalents" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
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  <xs:element name="MaximumNumberOfYearsFromDateOfSaleAgreementThatPaymentIsGuaranteed" id="mdu_MaximumNumberOfYearsFromDateOfSaleAgreementThatPaymentIsGuaranteed" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
  <xs:element name="TotalElectricRateIncreaseRequested" id="mdu_TotalElectricRateIncreaseRequested" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xs:element name="AmountOfApprovedInterimIncreaseInAnnualElectricRates" id="mdu_AmountOfApprovedInterimIncreaseInAnnualElectricRates" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xs:element name="RevisedTotalAnnualElectricRateIncreaseRequested" id="mdu_RevisedTotalAnnualElectricRateIncreaseRequested" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
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  <xs:element name="NumberOfMwOfSimpleCycleNaturalGasTurbine" id="mdu_NumberOfMwOfSimpleCycleNaturalGasTurbine" type="num:powerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="EstimatedProjectCostOfNaturalGasTurbineAndAssociatedFacilities" id="mdu_EstimatedProjectCostOfNaturalGasTurbineAndAssociatedFacilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xs:element name="ReductionsInRateIncreaseSoughtByRegulatoryAgency" id="mdu_ReductionsInRateIncreaseSoughtByRegulatoryAgency" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xs:element name="AmountOfTotalRateIncreaseIncludedInSettlementAgreement" id="mdu_AmountOfTotalRateIncreaseIncludedInSettlementAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xs:element name="TotalAmountOfRequestedInterimElectricRateIncrease" id="mdu_TotalAmountOfRequestedInterimElectricRateIncrease" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xs:element name="PercentageOfInterimElectricRateIncreaseRequested" id="mdu_PercentageOfInterimElectricRateIncreaseRequested" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
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  <xs:element name="AmountOfIndemnifiableLossesSoughtUnderIndemnificationAgreement" id="mdu_AmountOfIndemnifiableLossesSoughtUnderIndemnificationAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xs:element name="NumberOfAllegedPipelineSafetyRegulationViolations" id="mdu_NumberOfAllegedPipelineSafetyRegulationViolations" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
  <xs:element name="CashPaymentToBeMadePursuantToSettlementAgreement" id="mdu_CashPaymentToBeMadePursuantToSettlementAgreement" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
  <xs:element name="SuspendedPenaltiesRequiredIfNoncompliant" id="mdu_SuspendedPenaltiesRequiredIfNoncompliant" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
  <xs:element name="AmountOfAdditionalGuaranteesOutstandingReflectedOnBalanceSheetOfRelatedParty" id="mdu_AmountOfAdditionalGuaranteesOutstandingReflectedOnBalanceSheetOfRelatedParty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xs:element name="LettersOfCreditSetToExpireIn2011" id="mdu_LettersOfCreditSetToExpireIn2011" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
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  <xs:element name="NaturalGasInStorageNoncurrent" id="mdu_NaturalGasInStorageNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xs:element name="UndistributedEarningsOfEquityMethodInvestments" id="mdu_UndistributedEarningsOfEquityMethodInvestments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
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  <xs:element name="InterestRelatedToReversalOfUnrecognizedTaxBenefitsPreviouslyEstablishedFor2004Through2006TaxYears" id="mdu_InterestRelatedToReversalOfUnrecognizedTaxBenefitsPreviouslyEstablishedFor2004Through2006TaxYears" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xs:element name="PotentialLiabilitiesRelatedToLitigationAndEnvironmentalMatters" id="mdu_PotentialLiabilitiesRelatedToLitigationAndEnvironmentalMatters" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xs:element name="SiteContingencyLossExposureNotAccruedAndLowEstimate" id="mdu_SiteContingencyLossExposureNotAccruedAndLowEstimate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
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  <xs:element name="AmountOutstandingByPrairielandsUnderGuarantee" id="mdu_AmountOutstandingByPrairielandsUnderGuarantee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xs:element name="ForwardNotionalVolumesOnNaturalGasSwapAgreementsForDerivativeInstrumentsNotDesignatedAsHedgingInstrumentsInMillionMmbtus" id="mdu_ForwardNotionalVolumesOnNaturalGasSwapAgreementsForDerivativeInstrumentsNotDesignatedAsHedgingInstrumentsInMillionMmbtus" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
  <xs:element name="NonmonetaryNotionalAmountOfNaturalGasSwapAndCollarAgreementsInMillionMmbtuDerivativeInstrumentsDesignatedAsCashFlowHedgingInstruments" id="mdu_NonmonetaryNotionalAmountOfNaturalGasSwapAndCollarAgreementsInMillionMmbtuDerivativeInstrumentsDesignatedAsCashFlowHedgingInstruments" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
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  <xs:element name="BrazilianTransmissionLinesMember" id="mdu_BrazilianTransmissionLinesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="EcteMember" id="mdu_EcteMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="NaturalGasDistributionMember" id="mdu_NaturalGasDistributionMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="ElectricMember" id="mdu_ElectricMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="PipelineAndEnergyServicesMember" id="mdu_PipelineAndEnergyServicesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="ConstructionServicesMember" id="mdu_ConstructionServicesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="ConstructionMaterialsAndContractingMember" id="mdu_ConstructionMaterialsAndContractingMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="NaturalGasAndOilProductionMember" id="mdu_NaturalGasAndOilProductionMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="CommodityDerivativeInstrumentsMember" id="mdu_CommodityDerivativeInstrumentsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="NdpscMember" id="mdu_NdpscMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="MtpscMember" id="mdu_MtpscMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
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  <xs:element name="RegulatedOperationsRegulatoryMatterByRegulatoryAgencyAxis" id="mdu_RegulatedOperationsRegulatoryMatterByRegulatoryAgencyAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration"/>
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  <xs:element name="RegulatedOperationsScheduleOfRegulatoryMattersLineItems" id="mdu_RegulatedOperationsScheduleOfRegulatoryMattersLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="NaturalGasGatheringOperationsMember" id="mdu_NaturalGasGatheringOperationsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="GuaranteeObligationUnderConstructionContractMember" id="mdu_GuaranteeObligationUnderConstructionContractMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="LitigationRelatedToConstructionMaterialsMember" id="mdu_LitigationRelatedToConstructionMaterialsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="NaturalGasDistrbutionMember" id="mdu_NaturalGasDistrbutionMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="LossContingenciesByIndividualLitigationAxis" id="mdu_LossContingenciesByIndividualLitigationAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration"/>
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  <xs:element name="EnvironmentalLitigationNumber1Member" id="mdu_EnvironmentalLitigationNumber1Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="EnvironmentalLitigationNumber2Member" id="mdu_EnvironmentalLitigationNumber2Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="EnvironmentalLitigationNumber3Member" id="mdu_EnvironmentalLitigationNumber3Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="PortlandHarborSiteMember" id="mdu_PortlandHarborSiteMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="AmountOutstandingUnderGuaranteesThatIsReflectedOnBalanceSheet" id="mdu_AmountOutstandingUnderGuaranteesThatIsReflectedOnBalanceSheet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant"/>
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  <xs:element name="SiteContingencyLossExposureHighEstimate" id="mdu_SiteContingencyLossExposureHighEstimate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant"/>
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  <xs:element name="AmountOfDamagesDismissedInPendingLitigation" id="mdu_AmountOfDamagesDismissedInPendingLitigation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xs:element name="EstimatedDamagesIncludingInterestInAmendedComplaint" id="mdu_EstimatedDamagesIncludingInterestInAmendedComplaint" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xs:element name="PercentAboveCurrentRatesRequested" id="mdu_PercentAboveCurrentRatesRequested" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="NumberYearsContinuousServiceByDecember2010ToReceiveRetireeMedicalBenefits" id="mdu_NumberYearsContinuousServiceByDecember2010ToReceiveRetireeMedicalBenefits" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="InvestmentsUsedToSatisfyObligationsUnderNonqualifiedBenefitPlans" id="mdu_InvestmentsUsedToSatisfyObligationsUnderNonqualifiedBenefitPlans" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
  <xs:element name="AuctionRateSecurities" id="mdu_AuctionRateSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
  <xs:element name="BeforeTaxAmountOfIncreaseDecreaseInFairValueOfInvestmentsUsedToSatisfyObligationsUnderNonqualifiedBenefitPlans" id="mdu_BeforeTaxAmountOfIncreaseDecreaseInFairValueOfInvestmentsUsedToSatisfyObligationsUnderNonqualifiedBenefitPlans" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="DefinedBenefitPlanNetPeriodicBenefitCostAmountCapitalized" id="mdu_DefinedBenefitPlanNetPeriodicBenefitCostAmountCapitalized" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
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  <xs:element name="CommodityDerivativeLiabilitiesNoncurrent" id="mdu_CommodityDerivativeLiabilitiesNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xs:element name="CommodityDerivativeInstrumentsCurrentAssetsMember" id="mdu_CommodityDerivativeInstrumentsCurrentAssetsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
  <xs:element name="CommodityDerivativeInstrumentsCurrentLiabilitiesMember" id="mdu_CommodityDerivativeInstrumentsCurrentLiabilitiesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
</xs:schema>
