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Analytical procedures <br />Transmission electron microscopy/energy dispersive X-ray spectrometry/ <br />selected area electron diffraction (TEM/EDX/SAED) was employed in the <br />analysis of the sample. The water was homogenized in an ultrasonic bath and <br />an aliquot was drawn. The aliquot was diluted as needed (indicated by <br />screening) and an aliquot of the diluted sample was then drawn through a 0.22 <br />micron pore size mixed cellulose ester filter. A portion of the filter was <br />collapsed, etched, then coated with a thin layer of carbon in a carbon <br />evaporator. A small piece of the coated filter was placed onto a 3 mm <br />diameter copper TEM grid with the carbon side down. The sample was then <br />placed inside a Jaffe wick washer and treated with acetone to remove the <br />filter matrix and expose any inert material. <br />For each sample, ten grid openings on a 200 mesh TEM grid are searched for <br />fibrous structures which, if present, are analyzed by SAED and EDX (elemental <br />analysis). Level II protocol requires SAED confirmation of all asbestos <br />identifications. EDX confirmation is also required for the first 5 <br />chrysotile structures, the first 10 amphibole structures, and every tenth <br />structure after the 5 or 10 structure minimum is met. The morphology of each <br />structure is determined and the length and diameter of any asbestos <br />structures is recorded. Asbestos fibers, bundles, clusters, and matrices <br />were identified and recorded. These asbestos structures have been defined in <br />Yamate et al., as follows: <br />Fiber: is a structure having an aspect ratio Of 3:1 or greater with <br />substantially parallel sides. <br />Bundle: is a structure composed of three or more fibers in a parallel <br />arrangement, with each fiber closer than the diameter of one fiber. <br />Cluster: is a structure with fibers in a random arrangement such that <br />all fibers are intermixed and no single fiber is isolated from <br />the <br />group. <br />Matrix: is a fiber or fibers with one end free and the other end <br />embedded or hidden by a particulate. <br />If more than 100 asbestos structures are identified and confirmed on a <br />sample, Level II analysis may be terminated after completion of the grid <br />opening which contains the 100th structure. <br />Equations Used for Calculations <br /># Asbestos Structures Sff. Filter Area (mmZ) 1 1000 ml <br />Concentration --------------------- x -----------------------Z- x ---------------~- x ------- <br /># TEH GO Counted Average TEM GO Area (mm) Original Aliquot/ 1L <br />Dilution Factor <br />