Intrinsic bioremediation modeling to support Superfund site closure

Conference · Mon Sep 01 04:00:00 EDT 1997

OSTI ID:514847

Bedard, A H; Day, M J; Johnson, R H; Ritter, K J; Stancel, S G; Thomson, J A.M. ^[1]

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1. Applied Hydrology Associates, Denver, CO (United States)

Closure of the groundwater component of a major Superfund site has been accomplished by a combination of source control, engineered in-situ bioremediation, and subsequent long-term intrinsic bioremediation. Engineered bioremediation outside the source control area resulted in very significant contaminant mass removal. This allowed intrinsic bioremediation to be considered as a passive remedial management method of achieving cleanup objectives after active remediation needed. Modeling demonstrated that intrinsic bioremediation would achieve cleanup objectives (for this site, Federal drinking water standards) within ten years of shutdown of the active bioremediation system. Modeling showed that residual electron acceptors and nutrients distributed in the aquifer during engineered bioremediation greatly enhance the intrinsic bioremediation process. The results of the modeling effort led to the active system being shut down a year ahead of schedule, allowing the project to move into a low-maintenance intrinsic bioremediation and long-term monitoring phase. The modeling demonstration coupled Visual MODFLOW{copyright} and BioTrans{copyright} to simulate groundwater flow, solute transport, and oxygen-limited, multi-species biodegradation. Regional flow evaluation, detailed model sensitivity analyses, and subarea modeling were employed to provide support to model predictions. Predictions will be tested by subsequent progress and compliance monitoring. Site closure began in early 1996.

• OSTI ID: 514847
• Report Number(s): CONF-970456--
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AQUIFERS
BIODEGRADATION
CHEMICAL WASTES
ENVIRONMENTAL TRANSPORT
GROUND WATER
IN-SITU PROCESSING
MATHEMATICAL MODELS
REMEDIAL ACTION
SENSITIVITY ANALYSIS
TEXAS