Document 4J3xJ1D7eJ4G3K7wBMYZpjgkQ

'aoGc 0{>crJ(ioo 3705 Co^pofAic Avenue Suite t SO Cyixos. Ca 90030-473 3 (7 141 229-4000 fax (7 14) 229-400S PLAINTIFF'S EXHIBIT NAR-17Z Clayton (ENVIRONMENTAL CONSULTANTS August 31, 1994 Mr. Robert M. Owsiany, Esquire KIRKPATRICK & LOCKHART 1500 Oliver Building Pittsburgh, Pennsylvania 15222 Clayton Project No. 56848.00 Reference: Industrial Hygiene Evaluation of Harbison-Walker Metal-Clad Refractory Brick Relative to Airborne Asbestos Exposure Potential Dear Mr. Owsiany: I am a chemical engineer and senior industrial hygienist certified by the American Board of Industrial Hygiene. I entered the practice of industrial hygiene in 1972 and continue in that profession to the present. I currently hold the position of Vice President, Director, Technical Services, for Clayton Environmental Consultants, Inc. and am based in Clayton's Georgia office located at 400 Chastain Center Boulevard, N.W., Suite 490, Kennesaw, Georgia 30144-5558. I have testified as an expert witness regarding a variety of industrial hygiene and environmental matters, many involving asbestos. I have been admitted to testify before workmen's compensation hearings and county, state, and federal courts. A copy of my current curriculum vitae is attached for your review. At your request, I have reviewed the following materials: Industrial Hygiene Asbestos in Air Sampling Reports conducted by the United States Steel Corporation at its Homestead Steel Works 1/5 Open Hearth Shop, dated July 18, 1973; June 8, 1976; November 7, 1980; December l, 1980; and March 2, 1981 * Engineering Report of Thermal Effects on Asbestos Liners In Harbison-Walker Mcial-Clad Brick, by John R. Verna, P.E., dated August 1984 Expert Report involving 170?. Met:;! Encased firebrick with Chrysotilc AsbestosContaining Expansion - Allowance Paper by Richard C. Bradl, Pli.D.. dated August 25, 1993 Expert Repou Re: North American Refractories Co. (AHS-175) by Otto Wong, .Sol), dated October 15, 1993 Mr. Robert M. Owsiany, Esquire Kirkpatrick & Lockhart August 31. 1994 Clay Co a (NVICIIH W.K'l <M. ^(INSUl ( AKt "JL Page 2 Clayton Project No. 56848.00 * Expert Report titled "Fundamental Considerations with respect to Exposure toAsbestos from Metal Clad Refractory Brick Use", by Nurtan A. Esman, Ph.D., dated April 9. 1992 * Expert Report regarding metal-clad bricks by Nurtan Esman. Ph.D.. dated May 2, 1989 * Drawing titled: "Roof for Open Hearth Furnace" dated 1968 * Assorted drawings General title Open Hearth Plant U.S. Steel Homestead Steel Works Having reviewed these materials, l hold the following opinions regarding the potential for exposure to airborne asbestos Fibers from Harbison-Walker metal-clad brick, within a reasonable degree of scientific certainty. The construction of the metal-clad roof brick is sufficient to contain asbestos fibers from expansion strips within the metal jacket during open hearth furnace roof construction activities such that roof construction worker airborne asbestos fiber exposures remain very low. Review of available reports indicate air sampling was conducted by U.S. Steel Corporation for bricklayers and bricklayer helpers during furnace rebuilding activities at the Homestead Steel Works.. .Workers wore equipment which sampled air from their breathing zones. The sampling followed methods appropriate for comparison of results with the Occupational Safety and Health Administration (OSHA) standards for asbestos. Separate samples were analyzed with individual short-term results combined to form time-weighted average (TWA) concentrations. Results remained below 0.1 fibers per cubic centimeter (f/cc) as TWAs which is the most recent OSHA standard for asbestos (1994). At the time of original sampling, the OSHA standard was 5.0 f/cc being lowered to 2.0 f/cc in 1976 and 0.2 f/cc in 1986. all as TWAs. All sampling indicated airborne fiber concentrations well below the applicable standards in effect at the time. Available air sampling data indicate that during an open hearth furn?.cc campaign involving mctal-clad roof brick, measured airborne fiber concentrations for chargin floor employees remained very low, below prior and current OSHA exposure limit for asbestos Due to die tcmpui atm c experienced by roof brick during a furnace camnaign, combined with die nature of furnace operation, asbestos fibers within metal-clad brick ;uc likely converted, to eon-asbestos fr..-::.e.-;ic. .Sampling, lor airborne fib::;:; during furnace tear-out and debris removal indicated concentrations at or below lower t 0 CA 1 tAc. Robert M. Owsiany. lisquirc Kirkpatrick Sc Lockhart . vugust 31, 1994 Clayton iwwtO-vvi* k lZr CttMSut, t ANl S Page 3 Clayton Project No. 56848.00 limit of detection for the methods used. These very low results support the forsterilc conversion theory indicating an absence of fibrous material within roof debris. ?or any airborne contaminant, the highest airborne concentrations arc expected near a tourcc with concentrations lowering, due to dilution, as one moves away from the ;ourcc. Personal air samples typically describe the highest airborne concentrations. Vir sampling performed at source locations within and near open hearth furnaces luring roof construction, furnace operation, and roof demolition, consistently ndicates very low to marginally delectable airborne fiber concentrations. Mill areas nore distant from these potential source locations arc not expected to experience igniftcantly elevated, if even measurable, airborne asbestos fiber concentrations from ipen hearth furnace roof bricks. The phase contrast microscopy (PCM) method used for analysis of air samples in the eport reviewed counts as "fibers" any particle three times longer than wide with verall lengths greater than 5 micrometers. This can include materials other than sbestos. Additionally, there exist several potential sources of asbestos fibers in open earth steel mills beyond expansion strips enclosed within metal-clad bricks. An xample is asbestos expansion strips cut from stock and installed by bricklayers utsidc the metal enclosed bricks. One, therefore, cannot assume that fibers counted i tiie air sample reviewed, originated from expansion strips within Harbison-Walker ictal-clad roof bricks. harles L. Blake, CIH ice President ircctor, Technical Services LB/bb