Remediation levels, soil arsenic

Wellman, D.E., Reid, D.A. and Ulery, A.L. (1999) Elevated soil arsenic levels at a former crude oil storage facility-assessment, remediation, and possible sources. Soil and Sediment Contamination, 8(3), 329-41. 

Table 3 Range of Remediation Levels for Soil Arsenic at USEPA Superfund Sites...

Bagga, D.K. and Peterson, S. 2001. Phytoremediation of arsenic-contaminated soil as affected by the chelating agent CDTA and different levels of soil pH. Remediation Journal, 12(l) 77-85. 

Electrokinetic remediation involves passing a low level (mA cm ) DC electric current having potential difference a few volts through the soil, either in situ with electrodes placed into the soils, or in an external reactor. It has been shown that heavy metals such as zinc, copper, cadmium, chromium, lead, arsenic, mercury, nickel and iron can be efficiently removed from soils by electrokinetics. 

In situ metal immobilization employing phosphate is a cost-effective and environmental friendly technique of less disruptive nature [24, 28, 47, 76] than other remediation techniques such as soil removal, washing or leaching. This technique was suggested by the United States Environmental Protection Agency in 1996 as an alternative to soil removal for the amendment of urban lead-contaminated soils [27]. The treatment of waters with calcium oxide or hydroxide can precipitate dissolved arsenate. To attain a total dissolved arsenic level lower than the maximum permissible concentration for total arsenic in potable water (0.010 mg/L arsenic) it is necessary to have a pH higher than 12.5, which poses other environmental problems. Under these conditions calcium carbonate wiU be the thermodynamically stable solid phase under ambient surface conditions. Transformation of calcium arsenates into calcium carbonate wiU re-release arsenic into the environment. For pH > 12... 

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