HR: 10:50h
AN: H42B-02    [Abstracts]
TI: Performance Monitoring of MNA Remedies for VOCs in Ground Water: A Framework
AU: * Acree, S D
EM: acree.steven@epa.gov
AF: U.S. EPA, R.S. Kerr Environmental Research Center, P.O. Box 1198, Ada, OK 74821 United States
AU: Pope, D F
EM: dpope@dynamac.com
AF: Dynamac Corporation, 3601 Oakridge Blvd., Ada, OK 74820 United States
AU: Levine, H
EM: levine.herb@epa.gov
AF: U.S. EPA Region 9, 75 Hawthorne Street, San Francisco, CA 94105 United States
AU: Mangion, S
EM: mangion.steve@epa.gov
AF: U.S. EPA Region 1, One Congress St., Suite 1100, Boston, MA 02114 United States
AB: Effective monitoring of natural attenuation processes requires a clear understanding of hydrogeologic controls on ground-water flow, a three-dimensional approach to monitoring network design, and clearly defined performance criteria based on site-specific remedial action objectives. Objectives for the monitoring program generally will be met through routine evaluations of institutional controls and measurements of contaminant, geochemical, and hydrologic parameters. These data are used to evaluate changes in three-dimensional plume boundaries, changes in contaminant mass and concentration, and hydrological and geochemical changes that may indicate changes in remedy performance. Data interpretation focuses on detection of spatial and temporal changes, and assessment of their impacts on the achievement of site-specific goals. Particular changes of interest include:
- Progress toward contaminant removal objectives,
- Contaminant detections indicative of additional releases and detections at the plume boundaries that may indicate plume expansion,
- Geochemical changes (e.g., oxidation-reduction conditions) indicative of possible changes in contaminant transformation processes and rates,
- Changes in ground-water flow rates or directions such that contaminants may move into uncontaminated areas or threaten possible receptors, and
- Changes in land and resource uses that threaten the effectiveness of institutional controls. Decisions regarding remedy effectiveness and the adequacy of the monitoring program will generally result in either continuation of the program, program modification, modification of the remedy, or termination of the performance monitoring program. Such decisions are appropriately based on specific, quantitative performance criteria defined in a monitoring plan.
DE: 1829 Groundwater hydrology
DE: 1832 Groundwater transport
SC: Hydrology [H]
MN: 2005 Joint Assembly