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<!-- Creation Date      : 2016-11-02T16:26:09.8369809+00:00 -->
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<!-- Package ID         : 58F1A96FB7C11EC09C2132B4CC6445C7-0001372020-001608 -->
<!-- Copyright (c) 2016 R. R. Donnelley & Sons Company. All Rights Reserved. -->
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  <element id="gldd_DerivativeUnderlyingHedgePercent" name="DerivativeUnderlyingHedgePercent" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="gldd_EmployeesAndDirectorsMember" name="EmployeesAndDirectorsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="gldd_BidsBondRange" name="BidsBondRange" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <element id="gldd_OutstandingPerformanceBonds" name="OutstandingPerformanceBonds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <element id="gldd_RevenueValueRemainingFromOutstandingPerformanceBonds" name="RevenueValueRemainingFromOutstandingPerformanceBonds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <element id="gldd_CommitmentsAndContingenciesLineItems" name="CommitmentsAndContingenciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="gldd_CommitmentsAndContingenciesTable" name="CommitmentsAndContingenciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="gldd_WarrantyPeriods" name="WarrantyPeriods" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="gldd_TentativeSettlementSubjectToFinalDocumentation" name="TentativeSettlementSubjectToFinalDocumentation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="gldd_TerraseaEnvironmentalSolutionsMember" name="TerraseaEnvironmentalSolutionsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="gldd_MagnusPacificAcquisitionMember" name="MagnusPacificAcquisitionMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="gldd_GreatLakesEnvironmentalAndInfrastructureLLCMember" name="GreatLakesEnvironmentalAndInfrastructureLLCMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="gldd_MaximumPotentialAggregateEarnoutPayment" name="MaximumPotentialAggregateEarnoutPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="gldd_EnvironmentalAndInfrastructureSegmentMember" name="EnvironmentalAndInfrastructureSegmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="gldd_OwnedDomesticSubsidiariesPercent" name="OwnedDomesticSubsidiariesPercent" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
</schema>
