World Trade Center asbestos situation memorandum, December 2001

NYC 9/11 Public Portal Document

www.NYenviroLAW.org.

Dr. Millette was EPA’s principal investigator in developing EPA’s carpet ultrasonication method. In an email he stated the following:

This is an old claim [that the ultrasonication breaks down bundles of asbestos fibers into individual fibers, thus resulting in a higher count] developed by experts in litigation to try and discredit the dust method. There are ultrasonic instruments that range in power from those that are used to break up kidney stones to those that allow a mother to see her baby in the womb. The ultrasonic bath used in the carpet procedure is a mild mixing type that you can put your hand in. Because of the nature of the material (carpet) you cannot analyze ft directly. You must put the particles into suspension and mix them to get a good subsample for filtration and analysis. The ultrasonic mixing was adapted from the EPA water methods that were developed the 1970s. It represents the best technically feasible way to analyze the sample of dust/dirt presented.... The EPA carpet sonication method is the best technique available to assess carpet contamination.

The study by Granger, et al., HP Environmental, found that asbestos fibers in WTC fallout were already finely divided to such an extent by the explosion that no further separation of the fibers occurred with the use of ultrasonication.

In addition, ultrasonication is also used in other established asbestos methods, such as EPA’s indirect preparation method of air samples, as well as the ASTM microvacuum method 5755. Thus, nothing unusual in the carpet sonication procedure.

7. National Institute for Standards and Technology (NIST) National Voliuitary Laboratory Accreditation Program (NVLAP). National Laboratory Accreditation Administration, Gaithersburg, MD 20899, telephone 301-975-4016) http://ts.nist.gOv/ts/htdocs/210/214/scopes/temtm.htm.

8. Millette, J.R.; Clark, P.J.; Brackett, K.A.; Wheeles, R.K. (1993), op. cit.

9. Millette, J. R., etal. (1994), op. cit. 10. Kupferman, Joel (June 4, 2002) Personal communication. New York Environmental Law and Justice Project, 315 Broadway Suite #200, New York, New York 10007-1121, www.NYenviroLAW.org

11. Kupferman, Joel (June 4,2002), op. cit. 12. EPA (September 11,2001) EPA Monitoring Site: Reade & Hudson, Asbestos in Bulk Dust. EPA response to September 11. Posted at http://www.epa.gov/enviro/nvc/bulkdust.

13. Jenkins, C. (April 30,2002, with May 7 update) TEM vs. PLM METHODS FOR ASBESTOS DUSTS: TEM found over 1% asbestos, but PLM tests showed NONE; EPA PLM tests of WTC fallout dust may have underestimated area of asbestos contamination; EPA Region 2 knew TEM was required and needed, had it after the WTC collapse for their own building.

-29-

NYC-WTC_000140160