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  <xs:element id="kop_RevolvingCreditAgreementMember" abstract="true" name="RevolvingCreditAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kop_SwinglineRevolvingCreditFacilityMember" abstract="true" name="SwinglineRevolvingCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kop_AmendmentNumberOneToCreditFacilityMember" abstract="true" name="AmendmentNumberOneToCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kop_AmendmentNumberTwoToCreditFacilityMember" abstract="true" name="AmendmentNumberTwoToCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kop_SeniorSecuredCreditFacilitiesMember" abstract="true" name="SeniorSecuredCreditFacilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kop_DebtInstrumentFloorInterestRate" abstract="false" name="DebtInstrumentFloorInterestRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="kop_DebtInstrumentPercentageOfPrincipalPayment" abstract="false" name="DebtInstrumentPercentageOfPrincipalPayment" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="kop_BeazerEastMember" abstract="true" name="BeazerEastMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kop_PortlandHarborMember" abstract="true" name="PortlandHarborMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kop_PortlandHarborTrusteeClaimsMember" abstract="true" name="PortlandHarborTrusteeClaimsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kop_EnvironmentalRemedialSiteTwoMember" abstract="true" name="EnvironmentalRemedialSiteTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kop_UtilityAndIndustrialProductsMember" abstract="true" name="UtilityAndIndustrialProductsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kop_NumberOfSitesListedOnNationalPrioritiesList" abstract="false" name="NumberOfSitesListedOnNationalPrioritiesList" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="kop_NumberOfPotentiallyResponsibleParties" abstract="false" name="NumberOfPotentiallyResponsibleParties" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="kop_NetPresentValueOfSelectedRemedyEstimation" abstract="false" name="NetPresentValueOfSelectedRemedyEstimation" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kop_UndiscountedCostOfSelectedRemedyEstimation" abstract="false" name="UndiscountedCostOfSelectedRemedyEstimation" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kop_LossContingencyClaimsNumber" abstract="false" name="LossContingencyClaimsNumber" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="kop_LossContingencyNumberOfPlaintiffsFilingAnAppeal" abstract="false" name="LossContingencyNumberOfPlaintiffsFilingAnAppeal" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="kop_CostsOfParticipatingInPotentiallyResponsiblePartiesGroup" abstract="false" name="CostsOfParticipatingInPotentiallyResponsiblePartiesGroup" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kop_NumberOfAcquiredPlantSitesWithRecordedEnvironmentalRemediationLiability" abstract="false" name="NumberOfAcquiredPlantSitesWithRecordedEnvironmentalRemediationLiability" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
</xs:schema>
