Document M4oG8w6NqO9gaB08v37w1wz4L

. ~ ., walter c. mccrone associates, inc. ""' I. ? ' -") Mr. Joseph Blashka Crown Zellerbach Camas, Washington 98607 Dear Mr. Blashka: We have completed our examination by transmission electron microscopy and selected area electron diffraction of the talc sample C-Z, Camas which you submitted for determination of asbestos content. The sample was prepared by suspending a small portion of the powder in ethanol and ultrasonerating, to break up any aggregates. A small drop of the suspension was then placed on a previously carbon coated transmission electron microscope grid and allowed to dry. This grid was then examined in the transmission electron microscope. .".;. During this examination particles with a fibrous morphology r that is an aspect ratio greater then 3:1l,,''wweerre examined by selected area electron diffraction to determine their crystallography. Based on this selected area electron diffraction it was determined that a proportion of the sample consisted of a fibrous amphibole, tentatively identified as tremolite, 'and that this proportion was less than 10%. It should be pointed out that fibrous tremolite is defined in the Federal Register as asbestos, and that for the purposes of this definition a fiber is defined as a particle having ~ aspect ratio greater then 3:1, that is a length to width ratio of greater then 3:1. The tremolite particles observed in your sample, therefore, would be classed under existing OSHA regulations as asbestos. ' Thank you for consulting McCrone Associates. If you have any questions concerning this report please contact us. Yours sincerely, Richard M. Ellis, Jr. Research Microscopist CAM-251 RME:gb Ref: MA 8802 cc: Lou Murino REECC!EJvVEEo Gordon Gill MARCYPR-MA208581029-080010 DEPT.2820 SOUTH MICHIGAN AVENUE. CHICAGO. ILLINOIS 60616 312/8427100. CABLE: CHEMICRONEMIUlltl=JllV~