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  <element id="prim_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsToVestNumberOfShares" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsToVestNumberOfShares" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_DividendsAndEarningsPerShareAbstract" name="DividendsAndEarningsPerShareAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_NumberOfLeasedProperties" name="NumberOfLeasedProperties" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetWorkingCapital" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetWorkingCapital" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_PIAndESegmentMember" name="PIAndESegmentMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_PAndUSegmentMember" name="PAndUSegmentMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_UAndDSegmentMember" name="UAndDSegmentMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_CivilSegmentMember" name="CivilSegmentMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_NumberOfMortgagesAssumed" name="NumberOfMortgagesAssumed" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_VariableInterestEntityNumberOfEntities" name="VariableInterestEntityNumberOfEntities" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_SummarizedJointVenturesMember" name="SummarizedJointVenturesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_FloridaGasContractorsMember" name="FloridaGasContractorsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_CoastalFieldServicesMember" name="CoastalFieldServicesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLandAndBuildings" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLandAndBuildings" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_EngineeringAssetsMember" name="EngineeringAssetsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_CommercialEquipmentFinancingDueJune2018ToAugust2022Member" name="CommercialEquipmentFinancingDueJune2018ToAugust2022Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_IncreaseDecreaseInContractWithCustomerAssetNetCurrent" name="IncreaseDecreaseInContractWithCustomerAssetNetCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_ContractWithCustomerAssetTableTextBlock" name="ContractWithCustomerAssetTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_ContractWithCustomerLiabilityTableTextBlock" name="ContractWithCustomerLiabilityTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_RevenueRemainingPerformanceObligationExpectedTimingPercentage" name="RevenueRemainingPerformanceObligationExpectedTimingPercentage" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_ContractWithCustomerLiabilityAccruedLossProvisionCurrent" name="ContractWithCustomerLiabilityAccruedLossProvisionCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_IncreaseDecreaseInContractWithCustomerLiabilityCurrent" name="IncreaseDecreaseInContractWithCustomerLiabilityCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_MasterServiceAgreementCustomersMember" name="MasterServiceAgreementCustomersMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_NonMasterServiceAgreementCustomersMember" name="NonMasterServiceAgreementCustomersMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_UnitPriceContractsMember" name="UnitPriceContractsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_CostReimbursableContractsMember" name="CostReimbursableContractsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_ContractWithCustomerLiabilityModificationOfContract" name="ContractWithCustomerLiabilityModificationOfContract" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_ContractWithCustomerLiabilityDeferredRevenueCurrent" name="ContractWithCustomerLiabilityDeferredRevenueCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_ContractWithCustomerLiabilityCurrentMember" name="ContractWithCustomerLiabilityCurrentMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_ContractWithCustomerAccountsPayableDueToSubcontractors" name="ContractWithCustomerAccountsPayableDueToSubcontractors" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_FirstPaymentPeriodMember" name="FirstPaymentPeriodMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_SecondPaymentPeriodMember" name="SecondPaymentPeriodMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_DebtInstrumentPaymentPeriodicTerm" name="DebtInstrumentPaymentPeriodicTerm" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_WillbrosGroupIncMember" name="WillbrosGroupIncMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_UtilityTransmissionAndDistributionMember" name="UtilityTransmissionAndDistributionMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_CaliforniaUtilityMember" name="CaliforniaUtilityMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsContractAssets" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsContractAssets" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesContractLiabilities" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesContractLiabilities" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_StateDepartmentOfTransportationMember" name="StateDepartmentOfTransportationMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_CaliforniaUtilityProjectMember" name="CaliforniaUtilityProjectMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_PotentialIncreasePerAccordionFeature" name="PotentialIncreasePerAccordionFeature" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_LineOfCreditFacilityMaximumBorrowingCapacityAccordionFeature" name="LineOfCreditFacilityMaximumBorrowingCapacityAccordionFeature" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_WithdrawalLiabilityForMultiemployerPensionPlanMember" name="WithdrawalLiabilityForMultiemployerPensionPlanMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_InterestRateSwapAgreementPercentageOfDebtOutstandingInWhichInterestExchanged" name="InterestRateSwapAgreementPercentageOfDebtOutstandingInWhichInterestExchanged" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_NoncontrollingInterestDistributions" name="NoncontrollingInterestDistributions" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_NumberOfInstrumentsUsedForTrading" name="NumberOfInstrumentsUsedForTrading" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_AdjustedNotionalAmountPercentageOfPrincipalPaymentsOnTermLoan" name="AdjustedNotionalAmountPercentageOfPrincipalPaymentsOnTermLoan" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_CollectabilityOfReceivablesMember" name="CollectabilityOfReceivablesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_ScenarioForecastAdjustmentMember" name="ScenarioForecastAdjustmentMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_MidwestUtilityMember" name="MidwestUtilityMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRestrictedCashAndEquivalents" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRestrictedCashAndEquivalents" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_DebtInstrumentNumberOfTranches" name="DebtInstrumentNumberOfTranches" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForForeignTaxCreditsProvisionalIncomeTaxExpense" name="TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForForeignTaxCreditsProvisionalIncomeTaxExpense" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentContractLiabilities" name="BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentContractLiabilities" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="prim_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentLeaseObligations" name="BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentLeaseObligations" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
</xsd:schema>
