#!/usr/bin/env perl

use strict;
use warnings;
use autodie;

my $data_file = 'data_000.txt';
my $re = qr{^([^0-9-]+?)\s+([0-9-][ 0-9.-]+?)\s*$};
my @data;
open my $fh, '<', $data_file;

while (<$fh>) {
    next unless /$re/;
    my ($site, $info) = ($1, $2);
    $info =~ y/ /\t/s;
    push @data, join "\t", $site, $info;
}

# For demo only
use Data::Dump;
dd \@data;