The association between protists, bacteria, and dissolved organic carbon (DOC) in an oxygen-depleted, 6 km-long wastewater contaminant plume within a sandy aquifer (Cape Cod, MA) was investigated by comparing abundance patterns along longitudinal and vertical transects and at a control site. Strong linear correlations were observed between unattached bacterial abundance and DOC for much of the ...

[1] In this research, we investigate the large-time solution behavior of a representative bioreactive transport model under the conditions that the mixing of two required substrates occurs only in the directions transverse to groundwater flow. The transport physics is governed by the commonly used advection-dispersion equations at a steady uniform flow field. The microbial population dynamics a...

A new simulation-optimization methodology is developed for cost-effective sampling network design associated with long-term monitoring of large-scale contaminant plumes. The new methodology is similar in concept to the one presented by Reed et al. (Reed, P.M., Minsker, B.S., Valocchi, A.J., 2000a. Cost-effective long-term groundwater monitoring design using a genetic algorithm and global mass i...

Please cite this article in press as: Loden, P., et models. J. Syst. Software (2009), doi:10.1016/j.j In this paper, we present the use of a wireless sensor network in a lab for subsurface contaminant plume monitoring with the objective of automatic calibration of groundwater transport models. A tank configured to simulate an aquifer was used as a testbed, and a 2D model was created based on th...

Benzylsuccinate synthase (bssA) genes associated with toluene degradation were profiled across a groundwater contaminant plume under nitrate-reducing conditions and were detected in significant numbers throughout the plume. However, differences between groundwater and core sediment samples suggested that microbial transport, rather than local activity, was the underlying cause of the high copy ...

We investigate the spatial and temporal features of dense contaminant plumes dynamics in porous materials. Our analysis is supported by novel experimental results concerning pollutant concentration profiles inside a vertical column setup. We describe the experimental methods and elucidate the salient outcomes of the measurements, with focus on miscible fluids in homogeneous saturated media. By ...

In the mid-1990s, a groundwater plume of uranium (U) was detected in monitoring wells in the B-BX-BY Waste Management Area at the Hanford Site in Washington. This area has been used since the late 1940s to store high-level radioactive waste and other products of U fuel-rod processing. Using multiple-collector ICP source magnetic sector mass spectrometry, high-precision uranium isotopic analyses...

[1] How often does a contaminant ‘particle’ migrating in a porous medium set a distance record, i.e., advance farther from the origin than at all previous time steps? This question is of fundamental importance in characterizing the nature of the leading edge of a contaminant plume as it is transported through an aquifer. It was proven theoretically by Majumdar and Ziff (2008) that, in the 1d ca...

Knowledge of the distribution of groundwater contaminant plumes is needed to avoid pumping contaminated water, assess past exposure to contamination, and design remediation schemes to contain or treat the contaminated area. In most field cases, however, contamination is discovered by a small number of fortuitously located wells, and the full distribution of the plume is never known. This paper ...

In this paper the development of a quasi-three-dimensional numerical model that can be used for quantifying groundwater inputs and associated contaminant discharged from coastal aquifers into the coastal zone at a regional scale is presented. The present model is called MODSharp. In order to handle problems at a regional scale, the sharp interface approach which is used for conceptualising seaw...