Dead Horse Bay served as an unofficial dump for decades, and now as the sand is washed away the boroughs' history is slowly being revealed, one china plate and glass bottle at a time. It's popular with local archeologists (both ameteur "treasure hunters" and professionals) as they wade through New York City's past. But this year, a darker side of the city's history has emerged: traces of radon gas and gamma radiation exceeding ambient levels. As parts of the beach have been closed off, locals are worried: will their artifacts and their history now just wash out to sea? And when trash becomes treasured, do we have a responsibility to preserve it?