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  <xsd:element name="RevolvingCreditFacility2023Member" id="wldn_RevolvingCreditFacility2023Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LetterOfCredit2023Member" id="wldn_LetterOfCredit2023Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LineOfCreditFacilityContingentIncreaseAggregateMaximumBorrowingCapacity" id="wldn_LineOfCreditFacilityContingentIncreaseAggregateMaximumBorrowingCapacity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
</xsd:schema>
