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  <xsd:element name="EquityMethodInvestmentSummarizedFinancialInformationExpenses" id="prim_EquityMethodInvestmentSummarizedFinancialInformationExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="EquityMethodInvestmentNumberOfPotentialProjectsTerminated" id="prim_EquityMethodInvestmentNumberOfPotentialProjectsTerminated" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EquityMethodInvestmentNonRecoverableAmountOfNonReimbursedProjectDevelopmentCostsAndReservesForAssetsExpensed" id="prim_EquityMethodInvestmentNonRecoverableAmountOfNonReimbursedProjectDevelopmentCostsAndReservesForAssetsExpensed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="EquityMethodInvestmentPercentageOfShareInExpenses" id="prim_EquityMethodInvestmentPercentageOfShareInExpenses" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionAdditionalDisclosureAbstract" id="prim_BusinessAcquisitionAdditionalDisclosureAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionNumberOfBusinessDaysPriorToClosingDateUponWhichAveragePriceOfCommonStockIsBased" id="prim_BusinessAcquisitionNumberOfBusinessDaysPriorToClosingDateUponWhichAveragePriceOfCommonStockIsBased" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCostsAndEstimatedEarningsInExcessOfBillings" id="prim_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCostsAndEstimatedEarningsInExcessOfBillings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventoryOtherAssets" id="prim_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventoryOtherAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="BusinessAcquisitionGoodwillAndIntangibleAssetsTaxDeductiblePeriod" id="prim_BusinessAcquisitionGoodwillAndIntangibleAssetsTaxDeductiblePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ReserveForEstimatedExpenses" id="prim_ReserveForEstimatedExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="AccruedOverheadCostCurrent" id="prim_AccruedOverheadCostCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="LettersOfCreditMaximumBorrowingCapacity" id="prim_LettersOfCreditMaximumBorrowingCapacity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="LineOfCreditFacilityAnnualFeePercentage" id="prim_LineOfCreditFacilityAnnualFeePercentage" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DebtInstrumentPercentageOfCashProceedsRaisedFromIncurrenceOfIndebtednessAgreedToBeUsedForPrepayment" id="prim_DebtInstrumentPercentageOfCashProceedsRaisedFromIncurrenceOfIndebtednessAgreedToBeUsedForPrepayment" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DebtInstrumentThresholdOfNetProceedsFromCompletionOfEquityFinancingToBeUsedForDeterminingRequiredPrepayment" id="prim_DebtInstrumentThresholdOfNetProceedsFromCompletionOfEquityFinancingToBeUsedForDeterminingRequiredPrepayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="DebtInstrumentPercentageOfNetProceedsInExcessOfSpecifiedAmountFromCompletionOfEquityFinancingAgreedToBeUsedForPrepayment" id="prim_DebtInstrumentPercentageOfNetProceedsInExcessOfSpecifiedAmountFromCompletionOfEquityFinancingAgreedToBeUsedForPrepayment" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DebtInstrumentPeriodicPaymentTerm" id="prim_DebtInstrumentPeriodicPaymentTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DebtInstrumentFaceAmountNumberOfPortions" id="prim_DebtInstrumentFaceAmountNumberOfPortions" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="LineOfCreditFacilityTerm" id="prim_LineOfCreditFacilityTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="LineOfCreditFacilityNumber" id="prim_LineOfCreditFacilityNumber" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DebtInstrumentInterestRatePeriodDomain" id="prim_DebtInstrumentInterestRatePeriodDomain" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionContingentConsiderationEarnoutTargetPeriodDomain" id="prim_BusinessAcquisitionContingentConsiderationEarnoutTargetPeriodDomain" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionContingentConsiderationEBITDAForMeasuringPotentialCashPayment" id="prim_BusinessAcquisitionContingentConsiderationEBITDAForMeasuringPotentialCashPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="RelatedPartyTransactionAgreementAmount" id="prim_RelatedPartyTransactionAgreementAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="IncomeTaxPeriodOfStatuteOfLimitationsOfStateAndForeignJurisdictionsMinimum" id="prim_IncomeTaxPeriodOfStatuteOfLimitationsOfStateAndForeignJurisdictionsMinimum" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IncomeTaxPeriodOfStatuteOfLimitationsOfStateAndForeignJurisdictionsMaximum" id="prim_IncomeTaxPeriodOfStatuteOfLimitationsOfStateAndForeignJurisdictionsMaximum" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IncrementalCommonSharesAttributableToSharesIssuedToIndependentDirectorsUnderShareBasedPaymentArrangements" id="prim_IncrementalCommonSharesAttributableToSharesIssuedToIndependentDirectorsUnderShareBasedPaymentArrangements" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IncrementalCommonSharesAttributableToEmployeePurchasedSharesUnderShareBasedPaymentArrangements" id="prim_IncrementalCommonSharesAttributableToEmployeePurchasedSharesUnderShareBasedPaymentArrangements" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EarningsPerShareTable" id="prim_EarningsPerShareTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EarningsPerShareLineItems" id="prim_EarningsPerShareLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="StockholdersEquityTable" id="prim_StockholdersEquityTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="StockholdersEquityLineItems" id="prim_StockholdersEquityLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="StockRepurchasedDuringPeriodAverageSharePrice" id="prim_StockRepurchasedDuringPeriodAverageSharePrice" type="num:perShareItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BondsIssuedAndOutstanding" id="prim_BondsIssuedAndOutstanding" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="RevenuePercentage" id="prim_RevenuePercentage" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="GrossProfitAsPercentageOfSegmentRevenue" id="prim_GrossProfitAsPercentageOfSegmentRevenue" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="StockIssuedSharesContingentAgreementOne" id="prim_StockIssuedSharesContingentAgreementOne" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CommonStockIssuedDuringPeriodValueAcquisitionOne" id="prim_CommonStockIssuedDuringPeriodValueAcquisitionOne" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="CommonStockIssuedDuringPeriodSharesAcquisitionOne" id="prim_CommonStockIssuedDuringPeriodSharesAcquisitionOne" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="StockIssuedDuringPeriodValueWarrantsExercised" id="prim_StockIssuedDuringPeriodValueWarrantsExercised" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="StockIssuedDuringPeriodSharesWarrantsExercised" id="prim_StockIssuedDuringPeriodSharesWarrantsExercised" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CommonStockIssuedDuringPeriodValueAcquisitionTwo" id="prim_CommonStockIssuedDuringPeriodValueAcquisitionTwo" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="CommonStockIssuedDuringPeriodSharesAcquisitionTwo" id="prim_CommonStockIssuedDuringPeriodSharesAcquisitionTwo" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PreferredStockIssuedDuringPeriodValueAcquisitions" id="prim_PreferredStockIssuedDuringPeriodValueAcquisitions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="PreferredStockIssuedDuringPeriodSharesAcquisitions" id="prim_PreferredStockIssuedDuringPeriodSharesAcquisitions" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AdjustmentsToAdditionalPaidInCapitalPurchaseOfUnitsFromUnderwriters" id="prim_AdjustmentsToAdditionalPaidInCapitalPurchaseOfUnitsFromUnderwriters" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="StockIssuedDuringPeriodValueContingentAgreementTwo" id="prim_StockIssuedDuringPeriodValueContingentAgreementTwo" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="StockIssuedDuringPeriodSharesContingentAgreementTwo" id="prim_StockIssuedDuringPeriodSharesContingentAgreementTwo" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SharesOutstandingDuringPeriodValue" id="prim_SharesOutstandingDuringPeriodValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="SharesOutstandingDuringPeriodShares" id="prim_SharesOutstandingDuringPeriodShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DistributionsToPremergerStockholders" id="prim_DistributionsToPremergerStockholders" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="WarrantsAndPurchaseOptionsForPurchaseOfStockAbstract" id="prim_WarrantsAndPurchaseOptionsForPurchaseOfStockAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="WarrantsAndPurchaseOptionsForPurchaseOfStockTextBlock" id="prim_WarrantsAndPurchaseOptionsForPurchaseOfStockTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionPurchaseAdditionalCashDue" id="prim_BusinessAcquisitionPurchaseAdditionalCashDue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="BusinessAcquisitionContingentConsiderationPotentialCashCommonStockPayment" id="prim_BusinessAcquisitionContingentConsiderationPotentialCashCommonStockPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="ScheduleOfRevenuesFromExternalCustomersAndTotalAssetsByGeographicalAreasTableTextBlock" id="prim_ScheduleOfRevenuesFromExternalCustomersAndTotalAssetsByGeographicalAreasTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionCostOfAcquiredEntity" id="prim_BusinessAcquisitionCostOfAcquiredEntity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligations" id="prim_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligations" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherAccruedLiabilities" id="prim_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherAccruedLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="IncreaseDecreaseInCustomerRetentionDepositsAndRestrictedCashCurrent" id="prim_IncreaseDecreaseInCustomerRetentionDepositsAndRestrictedCashCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionCostOfAcquiredEntityCash" id="prim_BusinessAcquisitionCostOfAcquiredEntityCash" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedWorkingCapital" id="prim_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedWorkingCapital" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="BusinessAcquisitionPurchasePriceAllocationAssetsAcquiredTwo" id="prim_BusinessAcquisitionPurchasePriceAllocationAssetsAcquiredTwo" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="OneCustomerMember" id="prim_OneCustomerMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ConcentrationRiskNumberOfCustomers" id="prim_ConcentrationRiskNumberOfCustomers" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionCostOfAcquiredEntityAdditionalCashPayable" id="prim_BusinessAcquisitionCostOfAcquiredEntityAdditionalCashPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="SilvaContractingCompanyIncAndTarmacMaterialsLLCAndC3InterestsLLCMember" id="prim_SilvaContractingCompanyIncAndTarmacMaterialsLLCAndC3InterestsLLCMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionPurchasePriceAllocationAssetsAcquiredOne" id="prim_BusinessAcquisitionPurchasePriceAllocationAssetsAcquiredOne" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="BusinessAcquisitionPurchasePriceAllocationAssetsAcquiredThree" id="prim_BusinessAcquisitionPurchasePriceAllocationAssetsAcquiredThree" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="BusinessAcquisitionProFormaPercentageOfTaxRateUsedInCalculatingTaxesOnIncomeFromContinuingOperations" id="prim_BusinessAcquisitionProFormaPercentageOfTaxRateUsedInCalculatingTaxesOnIncomeFromContinuingOperations" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionsProFormaIncomeLossFromContinuingOperationsBeforeTax" id="prim_BusinessAcquisitionsProFormaIncomeLossFromContinuingOperationsBeforeTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionProFormaWeightedAverageNumberOfSharesOutstandingAbstract" id="prim_BusinessAcquisitionProFormaWeightedAverageNumberOfSharesOutstandingAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionProFormaWeightedAverageNumberOfSharesOutstandingBasic" id="prim_BusinessAcquisitionProFormaWeightedAverageNumberOfSharesOutstandingBasic" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionProFormaWeightedAverageNumberOfDilutedSharesOutstanding" id="prim_BusinessAcquisitionProFormaWeightedAverageNumberOfDilutedSharesOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionProFormaEarningsPerShareAbstract" id="prim_BusinessAcquisitionProFormaEarningsPerShareAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PartnershipsAndJointVenturesPolicyTextBlock" id="prim_PartnershipsAndJointVenturesPolicyTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfVariableInterestEntitiesWhoseFinancialResultsAreConsolidated" id="prim_NumberOfVariableInterestEntitiesWhoseFinancialResultsAreConsolidated" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AccruedLiabilityDueAcquireeSellers" id="prim_AccruedLiabilityDueAcquireeSellers" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="LineOfCreditFacilityMaximumBorrowingCapacityAtEndOfFiscalYear" id="prim_LineOfCreditFacilityMaximumBorrowingCapacityAtEndOfFiscalYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="BusinessAcquisitionNumberOfTargetsToBeAchievedForContingentConsiderationPotentialCashPayment" id="prim_BusinessAcquisitionNumberOfTargetsToBeAchievedForContingentConsiderationPotentialCashPayment" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionNumberOfPerformanceTargetsForContingentConsiderationCashPayment" id="prim_BusinessAcquisitionNumberOfPerformanceTargetsForContingentConsiderationCashPayment" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BusinessAcquisitionContingentConsiderationEBITDAMeausrementPeriodForPotentialCashPayment" id="prim_BusinessAcquisitionContingentConsiderationEBITDAMeausrementPeriodForPotentialCashPayment" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EffectiveIncomeTaxRateContinuingOperationsExcludingIncomeAttributableToNoncontrollingInterests" id="prim_EffectiveIncomeTaxRateContinuingOperationsExcludingIncomeAttributableToNoncontrollingInterests" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AmendedCreditFacilityWithPrivateBankAndTrustCompanyMember" id="prim_AmendedCreditFacilityWithPrivateBankAndTrustCompanyMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
</xsd:schema>
