Natural attenuation, monitored

Natural attenuation relies on natural processes to clean up or attenuate pollution in soil and ground-water. Natural attenuation occurs at most polluted sites. However, the right conditions must exist underground to clean sites properly. If not, cleanup will not be quick enough or complete enough. Scientists monitor or test these conditions to make sure natural attenuation is working. This is called monitored natural attenuation (MNA)94-96... 

U.S. EPA, Monitored Natural Attenuation of Chlorinated Solvents, Technical Report EPA-600-F-98-022, U.S. EPA, Washington, 1998. 

U.S. EPA, Use of Monitored Natural Attenuation at Superfund, RCRA Corrective Action, and Underground Storage Tank Sites, OSWER Directive 9200-4.17P, United States Environmental Protection Agency, Washington, DC. April 1999. Available at www.epa.gov/oust/directiv/d9200417.pdf, 2009. 

Rittmann, B.E., Monitored natural attenuation of MTBE, in MTBE Remediation Handbook, Moyer, E.E. and Kostecki, P.T., Eds, Amherst Scientific Publishers, 2003. 

Metal contaminants can in some cases be immobilized in situ by oxidation or reduction, or precipitated by reaction with sulfide. Sulfate reducing bacteria are sometimes stimulated to produce sulfide, or a sulfur-bearing compound such as calcium polysulfide can be injected into the subsurface as a reductant and sulfide source. In certain cases where the contamination poses little immediate threat, it can safely be left to attenuate naturally (e.g., Brady et al., 1998), a procedure known as monitored natural attenuation. 

U.S. Environmental Protection Agency, 1998, EPA Seminars Monitored Natural Attenuation for Ground Water. Office of Research and Development, EPA/625/K-98/001. 

Azadpour-Keeley, A., Russell, H. H., and Sewell, G. W., 1999, Microbial processes affecting monitored natural attenuation of contaminants in the subsurface, EPA/540/S-... 

Natural attenuation, often called intrinsic remediation, intrinsic bioremediation, bioattenuation, or monitored natural attenuation (MNA) is an in situ treatment technology for soil, sediment, or groundwater. The technology has been used for full-scale remediation of sites contaminated with volatile organic compounds (VOCs), total petroleum hydrocarbons (TPH), chlorinated solvents, explosives, inorganics, and metals. 

Cost Item Monitored Natural Attenuation In Situ Bioremediation Pump-and-Treat/ Activated Carbon Adsorption... 

Reisinger, H.J., Burris, D.R. and Hering, J.G. (2005) Remediating subsurface arsenic contamination with monitored natural attenuation. Environmental Science and Technology, 39(22), 458A-464A. 

US Department of Energy (US DOE) (1999) Decision-Making Framework Guide for the Evaluation and Selection of Monitored Natural Attenuation Remedies at Department of Energy Sites, Office of Environmental Restoration, p. 19. 

United States Environmental Protection Agency (U.S. EPA) (1999) Use of monitored natural attenuation at superfund, RCRA corrective action, and underground storage tank sites. Office of Solid Waste and Emergency Response Directive 9200.4-17P... 

Abstract This chapter studies the application of chemodynamic principles to select a remediation scheme at a Louisiana Superfund site (Petro Processors, Inc (PPI) sites). The current remediation scheme at the sites, monitored natural attenuation (MNA) is a direct result of this and other research conducted at Louisiana State University. In this chapter, the results from our studies on the adsorption and desorption, the desorption kinetics, the delineation of freely desorbing and desorption resistant fractions, and the bioavailability of the desorption resistant fraction are presented along with the implication of this research for the current remediation scheme. 

Mossing C., Larsen L. C., Hansen H. C. L., Seifert D., and Bjerg P. L. (2001) Monitored natural attenuation (MNA) of petroleum hydrocarbons in a heterogenous aquifer affected by transient flow. In The Sixth International in situ and on-site Bioremediation Symposium, Battelle Press, vol. 2,... 

Degradahon is the most interesting process, because the contaminants can be transformed into less harmful products (carbon dioxide and water). Engineered application of natural attenuation processes as a remedy is termed monitored natural attenuation (MNA, see US EPA). This involves a monitoring component in addihon to an evaluation of the natural attenuahon processes. 

The number of landfill plumes that have been remediated are very few compared to, for example, plumes with chlorinated solvents and hydrocarbons, and the remediation of leachate plumes has usually involved a combination of approaches focusing on the source remediation and monitored natural attenuation for the plume. 

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