Abstract
The current regulatory requirement for cover soils in landfills and surface impoundments is that the soils attain, upon compaction, a very low hydraulic conductivity of 10−7 cm/s or less. Although the influence of the interaction between waste chemicals and clay soil on waste migration has been extensively studied, attempts to incorporate as design components the effects of sulfidic (sulfide-bearing) clays on the integrity of clay caps have largely been ignored. These influences may include increasing the permeability of the cover to percolating moisture, enhancing erosion of clay covers, and killing of vegetation on downslopes of the cover. Consequently, it is suggested that clay cap designers test the acid-generating capabilities of potential clay cap materials before exploiting these earth formations. This can be done by incubating a sample of the candidate capping material (with pH > 3.5) under moist aerobic conditions (field capacity) at room temperature. The soil will be said to contain sulfidic materials if it shows a drop in pH (1 ∶ 1 by weight in water) of 0.5 or more units to a pH value of 4.0 or less within eight weeks. Decisions should then be made as to whether the soil should be avoided or used with amendments to the cap design.
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References
Darmody RG, Fanning DS, Drummond WJ Jr, and Foss JE (1977) Determination of total sulfur in tidal marsh soils by x-ray spectroscopy. Soil Sci Soc Am J 41:761–765
Dunn RJ (1983) Hydraulic conductivity of soils in relation to subsurface movement of hazardous wastes. PhD Dissertation. Department of Civil Engineering, University of California, Berkeley.
D'Appolonia DJ (1982) Slurry trench cut-off walls for hazardous waste isolation. Proceedings of the 13th annual geotechnical lecture series, Geotechnical Group, Philadelphia Section, American Society of Civil Engineers
Fanning DS (1991) Physical and chemical characteristics of “clays” used in landfill closures. Manuscript for presentation at the 1990–1992 landfill closure symposia at Rutgers Continuing Education Division, New Brunswick, New Jersey
Fanning, DS (1993) Salinity problems in acid sulfate coastal soils. In: Leith H and Al Massoum A (Eds), Toward the rational use of high salinity tolerant plants, vol 1. Kluwer Academic Publishers. Dordrect, The Netherlands: pp 491–500
Fanning DS and Fanning MCB (1989) Soil morphology, genesis, and classification. New York: John Wiley & Sons
Fanning DS, Rendenhorst MCB and Bigman JM (1993) Colors of acid sulfate soils. In: Bigman JM and Ciolkosz EJ (Eds), Soil color. Soil Science Society of America Special Publ. No. 31. Madison, Wisconsin: Soil Science Society of America pp. 91–108
Goldhaber MB and Kaplan IR (1982) Control and consequencies of sulfate reduction rates in recent marine sediments. In: Kittrick JA, Fanning DS and Hossner LR (Eds), Acid sulfate weathering. Special Publ. No. 10. Madison, Wisconsin: Soil Science Society of America
Lukas RG and Gnaedinger RJ (1972) Settlement due to chemical attack of soils. Proceedings of the ASCE Soil Mechanics and Foundation Division specialty conference on performance of earth and earth-supported structures. Lafayette, Indiana, pp. 1087–1104
McMullen MC (1984) Adaptability of selected conservation plant species in relation to pH and electrical conductivity of active acid sulfate soils in Baltimore Harbor dredged materials. MS thesis. College Park: University of Maryland
Nordstrom DK (1982) Aqueous pyrite oxidation and the consequent formation of secondary iron minerals, pp. 37–56. In: Kittrick JA, Fanning DS and Hossner LR (eds), Acid sulfate weathering. Special Publ. No. 10. Madison, Wisconsin: Soil Science Society America
Pavilonsky VM (1985) Varying permeability of clayey soils. Proceedings of the 11th international conference on soil mechanics and foundation engineering. San Francisco, California, pp 1213–1216
Soil Survey Staff (1992) Keys to soil taxonomy. SMSS technical monograph, 5th ed. SCS/USDA/AID. Blacksburg, Virginia: Pocanontas Press
Sweeney RE (1972) Pyritization during digenesis of marine sediments. PhD thesis. University of California, Los Angeles.
US Environmental Protection Agency (1982a) Handbook: Remedial action at waste disposal sites. EPA-625/6-82/006, Washington, DC
US Environmental Protection Agency (1982b) Surface impoundments: Liner systems, final cover, and freeboard control. Draft RCRA guidance document. OSWER, Washington, DC
US Environmental Protection Agency (1986b) Technical guidance document: Construction quality assurance for hazardous waste land disposal facilities. EPA/530/SW-86/031. OSWER Policy Directive No. 9472.003. Washington, DC
US Environmental Protection Agency (1988) Design, construction, and evaluation of clay liners for waste management facilities. EPA/530/SW-86/007F. Washington, DC
Wagner DP, Fanning DS, Foss JE, Paterson MS, and Snow PA (1982) Morphological and mineralogical features related to sulfide oxidation under natural and disturbed land surfaces in Maryland. In: Kittrick JA, Fanning DS and Hossner LR (Eds) Acid sulfate weathering. Special Publ. No. 10. Madison, Wisconsin: Soil Science Society of America
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Although some of the authors of this article are employees of the United States Enviornmental Agency, the paper has not been subjected to Agency review and no official endorsement should be inferred.
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Kargbo, D.M., Fanning, D.S., Inyang, H.I. et al. Environmental significance of acid sulfate “clays” as waste covers. Geo 22, 218–226 (1993). https://doi.org/10.1007/BF00767407
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DOI: https://doi.org/10.1007/BF00767407