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<!-- DFIN ActiveDisclosure(SM) XBRL Schema Document - http://www.dfinsolutions.com/ -->
<!-- Creation Date      : 2020-08-04T15:40:41.9270070+00:00 -->
<!-- Version            : 5.0.1.476 -->
<!-- Package ID         : 27013f17a05e45a3b9fae45353004c81 -->
<!-- Copyright (c) 2020 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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  <xsd:element id="gldd_EnvironmentalAndInfrastructureSegmentMember" name="EnvironmentalAndInfrastructureSegmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
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  <xsd:element id="gldd_QuantityOfOilSpill" name="QuantityOfOilSpill" type="num:volumeItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_StatutoryMaximumPenaltyForViolation" name="StatutoryMaximumPenaltyForViolation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
</xsd:schema>
