HR: 1330h
AN: H43C-02    [Abstracts]
TI: Developing a Framework for Performance Monitoring to Assess the use of Monitored Natural Attenuation for Remediation of Inorganic Contaminants in Ground Water
AU: * Ford, R
EM: ford.robert@epa.gov
AF: USEPA National Risk Management Research Laboratory, 919 Kerr Research Dr., Ada, OK 74820 United States
AU: Wilkin, R
EM: wilkin.rick@epa.gov
AF: USEPA National Risk Management Research Laboratory, 919 Kerr Research Dr., Ada, OK 74820 United States
AU: Puls, R
EM: puls.robert@epa.gov
AF: USEPA National Risk Management Research Laboratory, 919 Kerr Research Dr., Ada, OK 74820 United States
AU: Wilhelm, R
EM: wilhelm.ron@epa.gov
AF: USEPA Office of Air and Radiation, 1200 Pennsylvania Ave., N.W., Washington, DC 20460 United States
AU: Lovelace, K
EM: lovelace.kenneth@epa.gov
AF: USEPA Office of Solid Waste and Emergency Response, 1200 Pennsylvania Ave., N. W., Washington, DC 20460 United States
AB: The USEPA is leading an effort to develop technical documentation that provides the policy, scientific and technical framework for assessing the viability of MNA for inorganic contaminants in ground water (hereafter referred to as the Inorganics Framework Document). Development of the Inorganics Framework Document is being carried out in conjunction with site-specific assessments of the viability of MNA at sites with ground water contamination. For one of these field sites, researchers at the National Risk Management Research Laboratory are assessing the potential for natural attenuation of arsenic within a contaminated ground-water aquifer. Based on the current state of knowledge, arsenic is considered to be a contaminant for which application of MNA may be of marginal success. The mobility of arsenic in ground water is strongly dependent on partitioning to immobile aquifer solids. However, arsenic is susceptible to changes in chemical speciation due to shifts in redox chemistry resulting from abiotic and biotic processes. These potential changes in chemical speciation require that detailed information for assessing the stability of immobilized arsenic be collected in space and time. This observation has been confirmed as part of the field study, where it has been established that partitioning to sediments results in significant removal of arsenic from the aqueous phase. However, the partitioning process is readily reversible under reducing conditions, indicating that MNA cannot be used as a sole remedy for site cleanup. Notice: This is an abstract of a proposed presentation and does not necessarily reflect EPA policy.
DE: 1045 Low-temperature geochemistry
DE: 1832 Groundwater transport
DE: 1871 Surface water quality
SC: Hydrology [H]
MN: 2005 Joint Assembly