<simpleType name="CompactionTestEnumType">
  <union>
    <simpleType>
      <restriction base="string">
        <enumeration value="Proctor"/>
        <enumeration value="Modified Proctor"/>
        <enumeration value="California Test 216"/>
        <enumeration value="Porter static"/>
      </restriction>
    </simpleType>
    <simpleType>
      <restriction base="string">
        <pattern value="other:\w{2,}"/>
      </restriction>
    </simpleType>
  </union>
</simpleType>