Document V36Ny9Zxd0VQMJG4waxKmYqEN

r, 1 CAREY. CAREY-CANADIAN ASBESTOS A DIVISION OP PANACON CORPOKAYtOK P. O. SOX 15070, CINCINNATI, OHIO U.S.A. 45215 T6L6PHONS: 513-821-3000 CASUS: CARYMINCS TELEX: 21-4184 9 March 1972 ` . 1 R. W. Grigg Commodity Purchasing Manager Kaiser Gypsum Co. Inc. Kaiser. Center 300 Lakeside Drive Oakland, California 94604 . * Dear Ralph: ' The enclosed memo from R. J. Merrill, President, Carey-Canadian Mines, Ltd., is in answer to your inquiry of December 27 and further to my letter of January 7. We trust his reply will answer your questions. We are pleased to be of service. Sincerely, Harold F. X. Plate/jm Sales Manager Enclosure . RECEIVE# MAR 13 1972 KAISER CEMENT R GYPSUM PURCHASING OCRAPTMENT FROM: ' 'Internal correspondence H. F. X, Plate R. J. Merrill ,,"~7 reply by: DATE: - v* 'S V ' CC: 3-7-72 A. H. Bagenstose SUBJECT: LETTER FROM R. W. GRIGG, KAISER GYPSUM CO. December 27, 1971 I know of no better way to evaluate the health hazard of using our asbestos than to tell the story of our mining operations. ' I should first point out that our mine is located approximately 15 miles away from any of the .mines 'comprising the Thetford Mines group and that the majority of our employees live in the town of East Broughton, which can/be called a "company town" as our mining operation is its only industry. We .employ 300 hourly rated and 50 salaried employees. East Broughton developed in the shadow of and down-wind from our former mine. The Quebec Asbestos Corporation, which operated from 1918 to 1958. During that-period we-employed up to 150 men. Our ore bodies of chrysotile asbestos fibre contain the highest percentage of asbestos of any mine in Quebec and require much more crushing and grinding to release the asbestos than the ores of the' Thetford group or that of Johns-Manville. We recover the asbestos by dry milling, creating a lot of dust in the process. Modern mills collect this dust with a bag filter. The product of the bag filters is partly processed and graded to be sold as 7RF and 7TF. As there is insuf ficient market for all of the dust collected, the balance is discarded with the tailings product from the mill and is stacked in mountainous heaps adjacent to the mill. The Quebec Asbestos Corporation mill was not equipped with a bag filter. The extremely dusty air in the mill interior was passed through cyclone collectors and exhausted from them to the atmosphere. This pall of dust settled continually over the town. The tailings heaps were also up-wind from the town so dust from that source also covered the town. It was only in 19'5S* after we built our new operation, Carey-Canadian Mines, three miles northeast, and down-wind from the town, that the townspeople could breathe a dust-free atmosphere. Our new operation maintains worker environment below 10 fibres per c. c. and the dust from our tailings heaps is dissipated over an unpopulated area. c'--339-2 4/3??? Page Two '* a This somewhat detailed description of our former operations and the unfortunate former plight of our employees was necessary to show that our old employees, perhaps more than any from the other mines, should be experiencing serious problems of pneumoconiosis and bronchogenic cancer. This, however, is not the case. There are no compensable cases of asbestosis. among our employees nor do we have any knowledge that any of our employees may be expected to develop compensable asbestosis. All have been annually examined.at the Thetford Mines Industrial Clinic for the past 25 or 30 years. We have pensioners with over 50 years of service. When we closed Quebec Asbestos Corporation, we transferred all of our 150 employees to the new operation, thus many of our workers have over 25 years of service. No unusual incidence of bronchogenic cancer has been noted among our employees as compared with other mines. Dr. MacDonald's study included our present and former employees in the group of 11, 000 on which he reported. . Question No. 2 can be answered as follows: . a. Charging and blending operations should be adequately ventilated to maintain the worker environment below 12 fibres per c. c. for short periods and averaging below 5 fibres per c. c. b. Emptied bags should be baled, wrapped and sold as waste paper. Spills should be cleaned up with a vacuum cleaner, not by push broom. " c. The recommended respirator is 3M3710. d. The recommended dust monitoring technique is the Membrane Filter Method, a copy of which is enclosed. e. Since accidental, short term and over-exposure will not result in pneumoconiosis or lung cancer, no emergency * procedures are necessary. - * 3. Use and application procedures: Joint Compounds - Avoid creation of visible dust when mixing dry materials with water. An approved mask should be worn by all people working in the area of hand sandpapering but it would be better if an orbital sander equipped with vacuum dust collector could be used in place of handsanding. Wall Texture - Avoid creation of visible dust when mixing. Avoid overspray. Page Three vll. Ceiling Texture - Avoid creation of dust when.mixing. . .. . Laminating Compound - Avoid creation of dust when mixing. 4. (a) Copies-of proposed EPA and OSHA regulations are available to you. . (b) This question is covered in the above regulations. QlIC Si <>'/ ; . for .-snorr -.or : h.*