October 2, 2001-Mid-December, 2001: Specialists Take Air Samples One Mile North of Ground Zero

A team of specialists from UC Davis, known as the Detection and Evaluation of Long-range Transport of Aerosols (DELTA) Group, conducts air sampling from the roof of 201 Varick St., located one mile north-northeast of the WTC site, at the request of the Department of Energy. Regional meteorology will suggest that the monitoring equipment’s location at Varick Street probably receives material from the World Trade Center site about half the time. The group’s analysts use seven different techniques to analyze the data including synchrotron-induced X-ray fluorescence, scanning transmission ion microscopy and proton elastic scattering analysis, and soft beta mass measurements and scanning electron microscopy (SEM). DELTA will examine the samples for dozens of substances including carbon-based compounds from burning wood, plastic and carpets; glass shards; and asbestos. DELTA will release summary reports in December (see Early November 2001) and February (see February 11, 2002). [JOM, 12/1/2001; Dateline (Univ of Calif, Davis), 2/15/2002; Chemical and Engineering News, 2/18/2002]