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Profile: Gregory Meeker

Positions that Gregory Meeker has held:

  • Head of the USGS's microbeam laboratory

Gregory Meeker was a participant or observer in the following events:

Workers involved in the cleanup at Ground Zero find that much of the World Trade Center towers and their contents have been pulverized to dust. Charlie Vitchers, a construction superintendent who oversees the operation, says, “Apart from recoveries, we didn’t find one thing. Nothing. Not even a file cabinet.… As we were working on the pile, people were saying, ‘We’re not finding anything.’” He adds, “We weren’t going to find anything that was made out of wood. But you think we would have found a computer.… We found cell phones. We found shoes. But with regard to furniture, nothing, not a thing, not a desk, not a wall panel.… [F]or the most part there was nothing in the pile of debris that was recognizable.” Crane operator Bobby Gray says, “I don’t remember seeing carpeting or furniture. You’d think a metal file cabinet would make it, but I don’t remember seeing any, or phones, computers, none of that stuff. There were areas where there were no fires, which is not to say that they didn’t experience tremendous heat anyway. But even in areas that never burned we didn’t find anything.” He comments, “It was just so hard to comprehend that everything could have been pulverized to that extent. How do you pulverize carpet or filing cabinets?” [Stout, Vitchers, and Gray, 2006, pp. 143-144] According to Greg Meeker of the US Geological Survey, “Six million sq ft of masonry, 5 million sq ft of painted surfaces, 7 million sq ft of flooring, 600,000 sq ft of window glass, 200 elevators, and everything inside came down as dust” when the towers collapsed. “The only thing that didn’t get pulverized was the WTC towers’ 200,000 tons of structural steel.” [Chemical and Engineering News, 10/20/2003] Some people will later claim that this complete pulverization of the WTC is evidence of the towers having been brought down deliberately, using explosives. [Griffin, 2004, pp. 26; Griffin and Scott, 2006, pp. 46-47]

Entity Tags: Gregory Meeker, World Trade Center, Bobby Gray, Charlie Vitchers

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

US Geological Survey (USGS) scientists begin performing tests on the dust samples collected by USGS geophysicists, Gregg Swayze and Todd Hoefen, during the previous three days (see September 17, 2001-September 19, 2001-). Roger Clark (the astrophysicist who heads the AVIRIS program at USGS), Gregg Swayze, Todd Hoefen and Eric Livo (another USGS scientist) analyze samples in the Imaging Spectroscopy Lab and Gregory Meeker (head of the USGS’s microbeam laboratory) views samples with the scanning electron microscope and conducts energy dispersive spectroscopy. Other USGS scientists study the samples using X-ray diffraction, X-ray fluorescence, as well as chemical analysis and chemical leach testing. Within hours, the results from the various tests indicate the presence of asbestos and an “alphabet soup of heavy metals.” Each of the different techniques used to determine the chemical components of the dust “back each other up,” Swayze later explains to the St. Louis Post-Dispatch. “Some techniques can see more than others, and we were throwing in every technique we had in house,” he says. Tests revealed the dust to be extremely alkaline with a pH of 12.1 (out of 14). [St. Louis Post-Dispatch, 2/10/2002] and that some of it was as caustic as liquid drain cleaner. [St. Louis Post-Dispatch, 2/10/2002] “We were startled at the pH level we were finding,” Swayze adds. “We knew that the cement dust was caustic, but we were getting pH readings of 12 and higher. It was obvious that precautions had to be taken to protect the workers and people returning to their homes from the dust.” Sam Vance, an environmental scientist with the EPA, sends the results to officials at the EPA, the New York health department and US Public Health Service. [St. Louis Post-Dispatch, 2/10/2002]

Entity Tags: Roger Clark, US Geological Service, Todd Hoefen, Steve Sutley, Joe Taggart, Eric Livo, Robert Green, Phil Hageman, Geoffrey Plumlee, Gregg Swayze, Gregory Meeker

Timeline Tags: Environmental Impact of 9/11


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