nitrification and denitrification or by ion exchange either before or after nitrification.
Although the comparable data regarding trace inorganics (e.g., metals) and specific identifiable organic contaminants (including some disinfection by-products) are less extensive than those for major inorganic ions such as minerals and salts, substantial research and practical experience do exist regarding these compounds in municipal wastewater and their removal during waste treatment. For instance, removals of some priority pollutants and other potentially toxic organic compounds in wastewater treatment plants have been reported by a number of researchers, including Richards and Shieh (1986), Hannah et al. (1986), and Petrasek et al. (1982).
The ability of advanced wastewater treatment (AWT) processes to remove many trace chemical contaminants is well established. Numerous potable reuse studies have shown that AWT can produce water that meets U.S. drinking water standards. Table 2-2, for example, compares the quality of water produced by San Diego's Aqua III pilot plant, Tampa's Hookers Point AWT pilot plant, and Denver's Potable Reuse Demonstration Project to drinking water standards. (See Chapter 1, Boxes 1-4, 1-6, and 1-7 for a description of the treatment processes used in those AWT facilities.)
Most of the potable reuse projects reviewed in this report have conducted extensive analyses for identifiable organic compounds, including