Elements and Compounds in Waste Materials

I 9 Elements and Compounds in Waste Materials 1000 tons excavated rock... 

Table I lists the EPA contaminants and the criteria that EPA has established to constitute a hazardous toxic waste. Table 2 shows the concentrations of the inorganic contaminants in the extract from the phosphogypsum samples. All of the organic compounds listed by EPA as hazardous toxic waste.s were tested by the standard EPA procedure none were detected. These included endrin, lindane, methoxychlor, toxaphene, 2,4-D silvex, and 2,4,5-TP silvex. All of the metals listed in Table I were found to be present in the extract at concentrations lower than allowed by EPA (as shown in Table 2). Therefore, by EPA definition phosphogypsum is not a hazardous toxic waste material. This confirms earlier research conclusions 71 that the leaching of trace elements from phosphogypsum is not significant in introducing hazardous toxic waste materials into the environment.

Raw materials, such as ores, coal, crude petroleum, as well as waste materials, such as household waste and sewage sludge, are considered here as natural materials. They contain a large number of components and phases, in which the elements are distributed in the form of various compounds. Such substances are specified in practice by the following characteristics ... 

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