Appending an xml file

Hi,

I've created an xml document from a query and simply need after the document is created to append to this file so that each time the page is executed and I go to the directory where the file is stored, I can see all the submissions.  The code works fine (when its run the first time) but after that I keep getting a "Only one top level element is allowed in an XML document" error.  I've tried re-formatting the xml and playing with the attributes of the cffile tag to no avail.

Any thoughts??

Thanks in Advance

<CFOUERY NAME='qryGetResults" DATASOURCE="Kyo">

     Select school_id

     From tblSchool

     Where school_id = 13

</CFQUERY>

<!--Careate xml document object containing data-->

          <cfxml variable = "SchoolRec">

               <TrainingRequest>

                    <cfoutput query="qryGetResults">

                         <Required>

                              <school_num>#school_id#</school_num>

                              <school_name>#school_name#</school_name>

                         </Required>

                    </cfoutput>

               <TrainingRequest>

          </cfxml>

<cfset xmltext = ToString (SchoolRec)>

<cffile action="append" file="c:\Temp\School.xml" output="xmltext">