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<!-- Creation Date      : 2017-11-07T21:01:27.8247501+00:00 -->
<!-- Version            : 2.5.0.9 -->
<!-- Package ID         : B5EB29E7C1F3DE6759C61C48E750F73E-0001372020-001709 -->
<!-- Copyright (c) 2017 Donnelley Financial, LLC. All Rights Reserved. -->
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  <element id="gldd_LossContingencyDamagesSoughtEstimatedValue" name="LossContingencyDamagesSoughtEstimatedValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <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_DredgingSegmentMember" name="DredgingSegmentMember" 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>
