<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema xmlns="http://water.usgs.gov/XML/AQ" xmlns:xsd="http://www.w3.org/2001/XMLSchema" targetNamespace="http://water.usgs.gov/XML/AQ" elementFormDefault="qualified" version="1.0">
	<xsd:include schemaLocation="../shared/DateTimeWithDatum.xsd"/>
   
  <xsd:group name="HistoryGroup">
      <xsd:sequence>
         <xsd:element name="CreatorUserName" minOccurs="0">
            <xsd:annotation>
               <xsd:documentation>
                  <Definition>The user login identifier of the person or process that created a record.</Definition>
               </xsd:documentation>
            </xsd:annotation>
            <xsd:simpleType>
               <xsd:restriction base="xsd:token">
                  <xsd:minLength value="1"/>
                  <xsd:maxLength value="8"/>
               </xsd:restriction>
            </xsd:simpleType>
         </xsd:element>
	 <xsd:element name="CreateDateTime" type="DateTimeWithDatum" minOccurs="0">
		<xsd:annotation>
			<xsd:documentation>
				<Definition>The date and time that data record was first inserted.</Definition>
			</xsd:documentation>
		</xsd:annotation>
	</xsd:element>
         <xsd:element name="ModifierUserName" minOccurs="0">
            <xsd:annotation>
               <xsd:documentation>
                  <Definition>The user login identifier of the person that last modified the record.</Definition>
               </xsd:documentation>
            </xsd:annotation>
            <xsd:simpleType>
               <xsd:restriction base="xsd:token">
                  <xsd:minLength value="1"/>
                  <xsd:maxLength value="8"/>
               </xsd:restriction>
            </xsd:simpleType>
         </xsd:element>
	<xsd:element name="ModifyDateTime" type="DateTimeWithDatum" minOccurs="0">
		<xsd:annotation>
			<xsd:documentation>
				<Definition>The date and time that the data record was last modified.</Definition>
			</xsd:documentation>
		</xsd:annotation>
	</xsd:element>
         <xsd:element name="ApproverUserName" type="xsd:token" minOccurs="0" maxOccurs="1">
            <xsd:annotation>
               <xsd:documentation>
			<Definition>The user login identifier of the person that approved the data record.</Definition>
	       </xsd:documentation>
            </xsd:annotation>
         </xsd:element>
	<xsd:element name="ApprovalDateTime" type="DateTimeWithDatum" minOccurs="0" maxOccurs="1">
		<xsd:annotation>
			<xsd:documentation>
				<Definition>The date and time that the data record was approved.</Definition>
			</xsd:documentation>
		</xsd:annotation>
	</xsd:element>
      </xsd:sequence>
   </xsd:group>
</xsd:schema>
