Every day Rudy and Blanco rode the gravity tunnels at dizzying speeds, dipping, swerving, missing each other and a million others by margins too small to imagine, reaching out and picking up their loads, leaning back, feet first, eyes closed, silent screaming in the heady pounding rush until they could drop what they carried. Then that day there was a tunnelsplit, a spurting leak, the worst of all they had heard of and feared for, and spitting them up aboveground. Outside. Beyond the already-healing split their clone comrades stepped forward to replace them. Life went on. They dried and died.
First posted in quarterly http://www.101fiction.com 06 September 2015