Natural attenuation definition
Natural attenuation means a variety of physical, chemical or biological processes that, under favorable conditions, act without hu- man intervention to reduce the mass, toxicity, mobility, volume, or concentration of hazardous substances in the environment. These in situ processes include: Natural biodegradation; dispersion; dilution; sorption; volatilization; and, chemical or biological stabilization, transformation, or destruction of hazardous substances. See WAC 173-340-370(7) for a description of the expected role of natural at- tenuation in site cleanup. A cleanup action that includes natural at- tenuation and conforms to the expectation in WAC 173-340-370(7) can be considered an active remedial measure.
Natural attenuation means the reduction in the con- centration and mass of a substance and its breakdown products in groundwater or soils, or both, due to naturally occurring physical, chemical or biological processes.
Natural attenuation. ’ means the reduction in the con- centration and mass of a substance and its breakdown products in groundwater, due to naturally occurring physical, chemical, and biological processes without human intervention or enhancement. These processes include, but are not limited to, dispersion, diffu- sion, sorption and retardation, and degradation processes such as biodegradation, abiotic degradation and radioactive decay.
Examples of Natural attenuation in a sentence
Natural attenuation is the use of natural processes that reduce the concentrations of constituents over time.
Natural attenuation of discharged pollutants in the environment is not considered cleanup or abatement for purposes of evaluating this factor.
NOTE: Natural attenuation monitoring plans are not required if concentrations of all chemicals of concern are at or below the Natural Attenuation Default Concentrations referenced in Chapter 62-777, F.A.C. The plan must be signed and sealed by a registered P.E.
Natural attenuation monitoring was conducte from 1994 to September 2002.' Site Rehabilitation Completion Order was issued 3/20/03.
More Definitions of Natural attenuation
Natural attenuation means the reduction in the con- centration and mass of a substance, and the products into which the substance breaks down, due to naturally occurring physical, chemical and biological processes.
Natural attenuation means a verifiable approach to site rehabilitation that allows natural processes to contain the spread of contamination and reduce the concentrations of contaminants in contaminated groundwater and soil. Natural attenuation processes may include sorption, biodegradation, diffusion, dispersion, volatilization, and chemical reactions with subsurface materials.
Natural attenuation means the reduction in the mass or concentration in soils or ground water of a regulated substance, pollutant, contaminant, and the products into which a substance breaks down, due to naturally occurring physical, chemical, and biological processes, without human intervention. "Enhanced natural attenuation" means the enhancement of natural attenuation at a site by the addition of chemicals, biota, or other substances or processes. "Monitored natural attenuation" means the monitoring of natural attenuation as it occurs. The department in its discretion may consider natural attenuation or enhanced or monitored natural attenuation as remediation alternatives for a site when pollution or contamination on a site or property does not pose a threat to human health or the environment, and reasonable safeguards are established under this section or other provisions of state or federal law.
Natural attenuation means a decrease in concentration of a substance in ground water through operation of natural physical or chemical processes, including but not limited to adsorption, absorption, dilution, phase transfer, oxidation, organic complexation, biodegradation, dispersion and diffusion.
Natural attenuation means a reduction in mass or concentration of a chemical of concern in groundwater over time or distance from the release point due to naturally occurring physical, chemical, and biological processes, such as: biodegradation, dispersion, dilution, sorption, and volatilization.
Natural attenuation means the reduction in the mass or concentration in soils or
Natural attenuation means a verifiable an