Document 8VmDjm8ExMDoEJ5pJjvR7mkK5

Oil O'. August 13, 1956 Dohrman H. Byers, Asst. Chief Toxicological Section Public Health Service 1014 Broadway Cincinnati 2, Ghio Dear Dohrman: Enclosed are several samples to be analyzed for free silica and asbestos. In relation to the asbestos samples from ths Zonolite Company operations in Libby, I am not certain that the asbestos content of the ore, which according to the company varies from 2 to 205$, with about 10 average, is significant. In this respect I would appreciate any advice or consents you say have concerning the asbestos content of the ore they are using. -With all probability, the quarts content of ths samples would be negligible although the raw ore before benefielation sometimes contains a good deal of quarts granules throughout. Sample No. U, from the Zonolite Company is a composite electrostatic precipitator sample taken at several locations, jampled at the usual J cubic feat per minute for 58 minutes. This sample may or may not be sufficient for ary analysis. We would appreciate ary commenta you may have concerning this matter. Sincerely yours, BFW/dJc Benjamin F. Wake Acting Industrial Hygiene Engineer Division of Disease Control 20171663