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Effects on soil quality and crop establishment after incorporation of flue gas desulfurization by‐product (FGD) into soil as an amendment was assessed in a mesocosm study. Mesocosm units received applications equivalent to 0, 2.5, 5.0, 7.5, and 10% FGD residue [0, 25, 50, 75, and 100 tons acre−1]. Germination, biomass production, and elemental composition of corn (Zea mays L. var. Dekalb DK‐683), soybean [Glycine max (L.) Merr. var. Haskell Pupa 94], radish (Raphanus sativus L. var. Sparkler), and cotton (Gossypius hirsutus L. var. Deltapine 51) were determined. The quality of leachates and soil were also determined periodically. Flue gas desulfurization residue did not affect germination and all application rates stimulated aboveground biomass. Plants grown in FGD‐amended soil contained significantly elevated tissue concentrations of As, B, Se, and Mo. The FGD residue elevated surface soil pH from 5.5 (Control) to 8.1 (at 10% FGD). Leachate pH was unaffected by FGD, but salinity rose sharply with increasing application rates of FGD. Leachates contained higher concentrations of B, with small increases in Se and As. Flue gas desulfurization residue application caused an increase in total B, As, Mo, Se, and extractable Ca in the soil, but decreased Mn and Zn. Using FGD residues could have beneficial effects on crop establishment without detrimental effects on soil or leachate quality, at an optimum rate of approximately 2.5%. This material could alleviate surface acidity, and B and Mo deficiencies in plants. [ABSTRACT FROM AUTHOR]

A field study (1993–96) assessed the benefits of applying unusually high rates of coal fly ash as a soil amendment to enhance water retention of soils without adversely affecting growth and marketability of the turf species, centipedegrass [Eremochloa ophiuroides (Munro) Hack.]. A Latin Square plot design was employed that included 0 (control, no ash applied), 280, 560, and 1120 Mg ha−1 application rates of unweathered precipitator fly ash. The fly ash was spread evenly over each plot area, rototilled, and allowed to weather under natural conditions for 8 mo before seeding. High levels of soluble salts, indicated by the electrical conductivity (EC) of soil extracts, in tandem with an apparent phytotoxic effect from boron (B), apparently inhibited initial plant establishment as shown by substantially lower germination counts in treated soil. However, plant height and rooting depth were not adversely affected, as were the dry matter (DM) yields throughout the study period. Ash treatment did not significantly influence water infiltration rate, bulk density, or temperature of the soil, but substantially improved water‐holding capacity (WHC) and plant‐available water (PAW). Enhanced water retention capacity improved the cohesion and handling property of harvested sod. [ABSTRACT FROM AUTHOR]

The impact of mining and smelting of metal ores on environmental quality is described. Mines produce large amounts of waste because the ore is only a small fraction of the total volume of the mined material. In the metal industry, production of Cu, Pb, and Zn causes the greatest degradation of the environment. Copper mining produces extensivemine wastes and tailings and Cu smelting emits approximately 0.11 Mgof S per Mg of Cu produced in the USA. Zinc and Pb smelters release large quantities of Cd and Pb into the environment. Metal smelting and refining produce gaseous (CO2, SO2, NOx etc.) and particulate matter emissions, sewage waters, and solid wastes. Soil contamination with trace metals is considered a serious problem related to smelting; however, mining and smelting are not main sources of global metal input into soils. Other sources like discarded manufactured products, coal ash, agriculture, and transportation take a lead. Smelters are the main sources of atmospheric emissionsof As, Cu, Cd, Sb, and Zn on a global scale and they contribute substantially to the overall emissions of Cr, Pb, Se, and Ni. A quantitative evaluation of the environmental health effects of mining and smelting is difficult because of the complexity of factors involved and lack of consistent methodology. Nevertheless, the case studies described indicate that negative health effects could arise from Pb mining and smelting. Risk assessment revealed that food chain contamination by Cd from soils contaminated by smelting is very unlikely under the western diet. [ABSTRACT FROM AUTHOR]