Tracking Terror Underground

Abstract

At a secret operations center in lower Manhattan recently, investigators from the New York City Police Department (NYPD) and the Department of Energy’s Brookhaven National Laboratory (BNL) suddenly began punching numbers on cell phones and speaking over the crackle of walkie-talkies, trying to track down a “black box” apparatus that had mysteriously gone missing. The box was designed to sample a tracer gas as it moved through the New York City subway system. It was a tense moment of drama on the last of three test days this summer for the Subway-Surface Air Flow Exchange Study—also known as S-Safe—the largest urban airflow study ever conducted, according to BNL researchers. With the help of the police and some 100 local undergraduate science students, BNL researchers released inert perfluorocarbon (PFC) tracer gases in and near the New York City subway to trace the subway system’s airflow dynamics. Understanding how air—and any chemical, ...