var listItemInfo = '';
   var listItemEnumerator = collListItem.getEnumerator();
        $("#ddl").empty();
             while (listItemEnumerator.moveNext()) {
             var oListItem = listItemEnumerator.get_current();
             var newOption=   "<option value='"+oListItem.get_item('Department')+"'>"+oListItem.get_item('Department')+"</option>";
             $("#ddlDEP").append(newOption);