Potential environmental and health concerns in the disposal of wastewater-treatment solid wastes from synthetic fuels facilities

The objective of this study was to examine some of the potential environmental and health concerns that would be associated with the codisposal of wastewater treatment solids with the other solid wastes generated in synfuels plants. The following conclusions were drawn from this study: (1) The characteristics of many wastewater-treatment solids are largely unknown. An examination of the origins of these solid wastes suggests that most should prove nonhazardous under current Resource Conservation and Recovery Act (RCRA) protocols; however, some (e.g., tarry dusts settled from raw condensates) should be treated as hazardous until proven otherwise, while others (e.g., salts resulting from the evaporation of process condensates will definitely be hazardous. (2) Most wastewater treatment solids will probably be disposed of along with larger volumes of process-derived solid wastes. Connate water in the base of each type of landfill (ash, process waste, or codisposal) may change in character as the contents of the landfill age. (3) Wastewater-treatment solids may release previously immobilized toxic materials during long-term aging; this phenonenon is uncharacterized. (4) Detection of potential environmental and health concerns associated with the disposal of wastewater-treatment solids via monitoring of codisposal landfills will be impractical due to masking phenomena caused by othermore » solids in the landfill. (5) The adequacy of all landfill monitoring plans should be reviewed, with emphasis on the detection of slow releases of organics and trace heavy metals into the environment by the action of wind and rain. (6) Establishing data bases to resolve the uncertainties discussed in this study may require the designation of special landfills with carefully controlled components and mixes and the monitoring of such landfills over extended periods of time. 67 refs., 2 figs., 10 tabs.« less