Carbonate aquifer

The waste organic acids dissolved and formed complexes with iron and manganese oxides. These dissolved complexes reprecipitated when the pH increased to 5.5 or 6.0 because of neutralization of the waste by the aquifer carbonates and oxides. 

If the 14C in the same water is observed to contain 30 pmc, then this value should be multiplied by 1.3 in order to correct for 14C losses during reaction with aquifer carbonates 30 x 1.3 = 39 pmc. This value is then applied to the decay curve (Fig. 11.1), and an age of 7500 years is obtained... 

The rapid increase from 26 to 98% waste fluid in the deep monitoring well indicated that the nonneutralized waste dissolved the aquifer carbonates and developed a highly conductive karstic system, which was very alarming in terms of waste disposal in the aquifer. During all this time no chemicals arrived in the upper monitoring well. 

Talma, A.S., Vogel, J.C. and Heaton, T.H.E. (1984) The geochemistry of the Uitenhage artesian aquifer (carbonate solution in a closed system). Isotope Hydrology in Water Resources Development 1983, IAEA Vienna, 481 497. 

Another problem is when the carbon dioxide content of natural gas is too high and must be lowered to produce pipeline-quality gas. Although the current practice is to vent this CO, sequestration of CO, in underground geologic formations is being considered. Already, in the Norwegian sector of the North Sea, CO, has been injected into saline aquifers at a rate of 1 million tons a year to avoid... 

This chemistry has been investigated and implemented for wastewater minerahza-tion by oxidizing the organic pollutants. The process is very efficient, not selective and, as a consequence, almost all carbon matter can be removed. Topical areas also include soil and aquifer treatments, sometimes in combination with a secondary biotic process [145]. 

Kuhn EP, GT Townsend, JM Suflita (1990) Effect of sulfate and organic carbon supplements on reductive dehalogenation of chloroanilines in anaerobic aquifer slurries. Appl Environ Microbiol 56 2630-2637. 

Griebler C, M Safinowski, A Vieth, HH Richnow, RU Meckenstock (2004) Combined application of stable carbon isotope analysis and specific metabolites determination for assessing in situ degradation of aromatic hydrocarbons in a tar oil-contaminated aquifer. Environ Sci Technol 38 617-631. 

Organic contaminants (as measured by dissolved organic carbon) continue to move through the aquifer even when acidity has been neutralized. 

The Belle Glade site, located southeast of Lake Okeechobee in south-central Florida, illustrates some of the problems that can develop with acidic-waste injection when carbonate rock is the confining layer. Contributing factors to the contamination of the aquifer above the confining zone were the dissolution of the carbonate rock and the difference in density between the injected wastes and the formation fluids. The injected waste was less dense than the groundwater because of its lower salinity and higher temperature.172... 

The wastes are injected into the lower part of the carbonate Floridan aquifer, which is extremely permeable and cavernous. The natural direction of groundwater flow is to the southeast. The confining layer is 45 m (150 ft) of dense carbonate rocks. The chloride concentration in the upper part of the injection zone is 1650 mg/L, increasing to 15,800 mg/L near the bottom of the formation.172 The sources used for this case study did not provide any data on the current injection zone. The native fluid was basically a sodium-chloride solution but also included significant quantities of sulfate (1500 mg/L), magnesium (625 mg/L), and calcium (477 mg/L). 

Kaufman, M.I., Goolsby, O.A., and Faulkner, G.L., Injection of acidic industrial waste into a saline carbonate aquifer geochemical aspects, in Symposium on Underground Waste Management and Artificial Recharge, Braunstein, J., Ed., publication 110, International Association of Hydrological Sciences, 1973, pp. 526-555. 

OmambiaA.N. and Li Y. Numerical modeling of carbon dioxide sequestration in deep saline aquifers in Wangshang Oilfield-Jianghan Basin, China. 2010 Journal of American Science 6(8) 178-187. 

Piatt, J.J., Backhus, D.A., Capel, P.D., Eisenreich, SJ. (1996) Temperature-dependent sorption of naphthalene, phenanthrene, and pyrene to low organic carbon aquifer sediments. Environ. Sci. Technol. 30, 751-760. 

Stauffer, T.B., MacIntyre, W.G., Wickman, D.C. (1989) Sorption of nonpolar organic chemicals on low-carbon-content aquifer materials. Environ. Toxicol. Chem. 8, 845-852. 

Sanchez JA, Coloma P, Perez A (1999) Sedimentary processes related to the groundwater flows from the Mesozoic Carbonate Aquifer of the Iberian Chain in the Tertiary Ebro Basin, northeast Spain. Sediment Geol 129 201-213... 

Grove, D. B., Rubin, M., Hanshaw, B. B., Beetem, W. A., Carbon-14 dates of ground water from a Paleozoic carbonate aquifer, southcentral Nevada, U. S. Geol. Survey Prof. Paper 650-C, p. 215-218, 1969. 

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