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  <xs:element id="psx_AccrualForEnvironmentalLossContingenciesExpectedPeriodToIncurMajorityOfExpenditures" abstract="false" name="AccrualForEnvironmentalLossContingenciesExpectedPeriodToIncurMajorityOfExpenditures" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
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</xs:schema>
