Toxic metal organic waste sites

The polysulfides, thiosulfate and sulfite, which are generally metastable relative to sulfate, are most abundant near groundwater redox interfaces where they can complex with borderline or soft metal cations (cf. Barnes 1979 Daskalakis and Helz 1992). Many sedimentary and hydrothermal ore deposits are found at redox interfaces where the breakdown and formation of such complexes may have locally caused metal precipitation and remobilization (cf. Granger and Warren 1969 Boulegue and Michard 1979 Barnes 1979). Similar metal-sulfur species mobilization may also occur in the vicinity of some toxic metal-organic waste sites. 

Hazardous wastes range from synthetic organic chemicals to heavy or toxic metals, to inorganic sludges, to solvents, to dilute aqueous streams. They may be solid, liquid, or gaseous they may be pure materials, complex mixtures, residues and effluents from operations, discarded products, or contaminated containers or soil. Most liazardous wastes are managed on the site where they are generated, mere so in some btates and... 

Humic and FULVIC acids, along with other organic colloidal materials, are fascinating substances that can have profound environmental consequences. Their abilities to complex radionuclides and toxic metals have been recognized for some time by researchers interested in the migration and mobilization of nuclear and industrial waste at contaminated sites. The micellar properties of humic and fulvic acids also give them the ability to play important roles in the solubilization and transport of hydrophobic pollutants. 

A number of NORM waste streams would be classified as hazardous if not for the presence of enhanced radioactivity, with important implications for handling and waste disposal. The main categories present are toxic heavy metals, organic compounds and asbestos. The latter is particularly problematic there are few facihties that can conduct measurements on radioactive, asbestos-containing material and very few sites that can accept such wastes for disposal. 

Leachates from ISW and municipal solid waste (MSW) sites contain complex mixtures of toxic chemicals. These include heavy metals (iron, nickel, zinc, manganese, chromium, cadmium, and lead) as well as numerous organic compounds (including aliphatic and aromatic hydrocarbons, PAHs, alcohols, esters, aldehydes, and pesticides). Specific compositions of leachates vary with pH, soil type, and specific chemicals contained in the sites. All ISW and MSW sites, however, leach toxic mixtures of chemicals. 

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