use strict;
  use Data::Dumper;
  foreach my $thisrow (@dept) {
    if (ref($thisrow) eq 'ARRAY) {
      my @columns = @{$thisrow};
      foreach (@columns) {
        # do something
      }
    }
    else {
      print "Hey!  That's not an array reference!\n";
      print Dumper($thisrow);
    }
  }