Chemical speciation of lead compounds in street dusts

Chemical associations of lead, cadmium, copper, and zinc in street dusts and ... Dynamic Characteristics of Particle Size Distribution in Highway Runo...
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he curtailed until an accurate, standard analytical asbestos counting method is developed that can measure significant reductions in asbestos across treatment processes at ambient levels. Also, given that above, it is recommended that further studies be pursued under pilot plant conditions in an area with a significant asbestos concentration in the raw water.

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ASBESTOS FIBRE CONC (FIBRES2 )

Figure 2. Asbestos fiber concentrations as a function of turbidity: a composite plot of all data repofted in Table II

that optimized conventional treatment can significantly reduce chrysotile levels in potable water. I t is felt that objective predictions and/or conclusions as to treatment efficiency are presently impossible given the current state-of-the-art in counting technology. Analytical methodology for chrysotile asbestos in water in often not sufficiently precise to detect concentration changes across unit processes. No definite correlation between fiber concentration and turbidity was observed. Consistent quantitative analysis of chrysotile asbestos fibers in river water following fortification with a concentrated chrysotile asbestos suspension could not be obtained.

(1) Cunningham, H. hl., Pontefract. K., .Vature (London),232,332-3 (1971). ( 2 ) Kay, G., Water Poiiut. C’ontroi ( C a n . ( 3 ) Kay, G., J . ,Am. W a t e r W o r k s ASSOC., ( 4 ) Iiiwrence, .J.. Zimmermann, H. \V., 1Vatc.r K(..s., 10, 195-8 (19761. I,a\vrence, .J., ‘I’osine, H. hl.. Zinimermann. H. it-.,Pang. T, \V. S..WatcJrKtJs., 9, :197-400 (1975). ( 6 ) I,ogsdon, G.S.. Symons. .I. hl., J . A m Water Wori;s d , ~ . s ( i c .69, , 499-306 (1977). ( 7 ) (;lass, K.\V.,“Improved Xlethodology for Determination of Asbestos as a Water Pollutant”, report of work performed under Contract SZ02.KL347-4-2073.CCIW, Burlington, Ontario, Canada, April, 1976. (8)Hallenheck. \V.H., Chen, E. H., Patel-Mandlik. I