A utl_raw.cast_to_Varchar2()
is needed to get results:
<cfquery name="select" datasource="DATA1">
SELECT UTL_RAW.CAST_TO_VARCHAR2(DBMS_LOB.SUBSTR(*name_of_field*))
FROM DATA1.TEST_BLOB
</cfquery>
OR
To return the data without casting
Go to the CF admin setting for the DSN, there are advanced setting that enable BLOB data