Document R4RqLGjJgg2y6BKKoKVvRBoz

11/21/1997 17:F 2c: R. M. Vjning H. C. Duecker 0- M. Fevoriro J. u. Uoicer g,'S,UJ. iWt-- 5 To: H. A. Broun y2^{i Fron: R. E. Locke SubJ: Fxecnt Sampling in Connection with Cashs Cirericcs 4 and 5 (I'roduct end Waste) 0628SS1 March 11, 1976 1. Saepllng Conclusions: Bated upon thasc very ev, hurried tests which would be dee to verify between plants and vith mor job sites, A, Both Concrete Aggregate enc Honokote ere undfii 2 fibre, pro* bably due to outdoor u3e wish free eir circulation. Only Dallas product has been tested, hc^rvor, and thcra may be pleat to pitot variations in addition to civ: job aits variations, B./C. Both Attic Fill and Masonry Fill exceed the 2 and 5 fibre levels. This necessitates a binder dcvslopcshc program or other reasdy. D, Horticultural appears to be no problotu E./F. retting stener rock appears to put us below the 2 fibre level on waste disposal. Other. The above represent over 507, Libby output. Industrial (not tasted' but 51 of Libby) probably approximate? Attic and Concrete Aggre gate depending upon ore 6ict; application geometry, and ventilation. 2. Using the Oc-aha extension to 31 Lccchbar 1976 for action on items 4 and 5, a Binder DevelopDent Jrogrea should ba initiated imediately. If the program Is unsuccessful, tmeconeale, requires astear-ivn plant modifications to icplesent or runs into timing problems, back-up erasures will be necessary. Such back-up prograss night include: Reformulating Attic Fill; Restricting Masonry Fill to S.C. vU with freight cost penalty in northern nsrkets, or substitution of perlite fron expanding plants so equipped; Acceleration of vet mill clean-up potential; Lcv-y.r.crua furnace settings; Teflon binding; Air allutriation; end other. Sent of the above am unlikely. However, back-up is the point. A review of the l.'csr Chicago ctoner discharge voter spray should be possible soon. Last, It should be noted the potential eniste chat OSHA eight inspect another plant sad e different Regional Office night issue doadlincs on product or rock earlier than the extended Cnahr. deadlines (the sacs applies to che September 30, 1977 deadline for 2 fibre). In that event, Omaha timing could conceivably be cited as a precedent for uniformity at 31 Dececher 1376 sad 30 September 1977. 15140424 H. A. Brown ivTiJili 2* - March 11, 1976 D-TAIl 1, Sacoling. Sampling of selected products vao core during .the last two weeks of February. The sanplec are not representative of all plants and of all uses of Libby products, but several conclusions acy be drawn. A. Concrete Aggregate and Moraho;? (Sampling on jobsites with Dallcs-nads Libby Ok product) 0G1SS552 Contractor employees opening bigs, operating nlxere, and disposing of bags received the highest closures, but thefle vere below the July 1st 2 fibre tolerance level (highest closures were 1,0 to 1.5). Mor.okcte gun operators (who routinely wear respirators) may be subject to 1.0 levels. Contractor employees cleaning up dried Konokece nay receive levels between Z and 5 fibres. The fibre con centrations on ch- roof (all less than 1 fibre) were probably a result of fibres from the ground sixer Cret. In senary, It appears that application of Zcnolite Insulating Concrete end Honchote do not creat-2 fibre exposures over 5 or 2 with two qualifying remarks; that (c) all sailing was out of doors or in wall-less buildings and (o) the Libby 4 product was from the Dallas plant exclusively (Raxtrance: XoA 48871). B. Attic Fill Attic Fill,tested twice, in its current fort: creates fibre counts in excess of the 5 fibre level generally and in excess of the 10 fibre ceiling in sene instances, h'ettit-g with water to approximately 2% quarts per 3 cu.ft, bag reduces fibre counts to apprexisately the 2 fibre level. Sampling of Attic Fill 1C hour? 18 nontha after application indicates essentially no airborne residual fibres in the attic area following prior applications of vemiculite (Reference: ?&A 48378 and -P43E30). C. Masonry 7111 (Asphalt Treated) Hasonry Fill (asphalt treated); tested twice, creates fibre counts in excess of the 5 fibre level generally, and in excess of the 10 ceiling level in aooc instances. Coup arid with the Insulating Concrete end Monokote samples (also Libby C-k). the geometry of filling' a hollow vail from above nay be the reason for the higher fibre counts. To seme degree the expanding plant any also be part of the reason (Dallas D-18; Trenton Model A). As was the case with Attic Fill, once pouring eeases, the fibre counts rapidly decline to nearly zero. (Reference: T&A 45880 and 48885). A test will occur week of 15 te 19 March using liasonTy Fill vetted like the Attic Fill experiment above. If the "fine-.-ballG" experienced with the wet Attic Pill occur with Msser.ry Fill, pouring into block cores may be difficult, (4<?org') 3.5146425 K. A. Brown CCKFiBEHTIAL 3- March 11, IS76 D. Horticultural tests on con>uner U6e of Ready Earth and Terrelite Verrticulite Indicate essentially no airborne fibres, or less than 0.1 fibre (Reference: 7&A #48890). E. Dry Stoner Rock in Onaha creates fibre exposures beeween 2 and 3 fibres for an eroloyee transporting it to the dim?6Cer while he firno is doing it. Eis d=e weighted average cay differ. Ihe contractor^ ecployee disposing of the vasts in Che duspster is exposed to less than 1 fibre (0.6) even though in close proxisity at the dusp (Reference: ISA 48B77). P. Vet Stoner Rock in W. Chicago; conclusions are haspcred both by ell West Chicago settles being Engineering type and by inconsistencies in th data versus Ocaha. However, it appears the vetted rock nay be veil below the 2 fibre level for enoloyee exposures (Reference: T6A 04BB72). RHL/cgr R. H. Locke 13148426