Swarm Intelligence (SI) based inverse model is developed for the first time, to recover the release history of a groundwater contaminant plume from the forensic observations. The flow system is assumed to be one-dimensional, with the plume originating from a known single site. The contaminant transport model is solved using explicit finite-difference scheme for the forward solution. The inverse...

Reconstruction of intentional or accidental release of contaminants into the atmosphere using concentration measurements from a sensor network constitutes an inverse problem. An added complexity arises when the contaminant is released from multiple sources. Determining the correct number of sources is critical because an incorrect estimation could mislead and delay response efforts. We present ...

The intentional or accidental large-scale release of a chemical-biological agent in an urban zone remains a viable threat to Homeland Security. As these silent, invisible and odorless plumes can cause massive casualties that would overwhelm emergency facilities, modeling, tracking and real-time prediction of plume dispersion and lethality is central to developing a user-friendly first responder...

We present a simulation/optimization model combining optimization with BIOPLUME II simulation for optimizing in-situ bioremediation system design. In-situ bioremediation of contaminated groundwater has become widely accepted because of its cost-effective ability to achieve satisfactory cleanup. We use parallel recombinative simulated annealing to search for an optimal design and apply the BIOPL...

A large-scale, natural-gradient tracer test in a heterogeneous aquifer at a site near Columbus, Miss. is simulated using three-dimensional (3D) hydraulic conductivity distributions derived from the borehole flowmeter test data. The simulated plume is more sensitive to the way the hydraulic conductivity field is interpolated from the measured data than it is to the dispersivity value. The transp...

The Gaussian plume model is a standard approach for studying the transport of airborne contaminants due to turbulent diffusion and advection by the wind. This paper reviews the assumptions underlying the model, its derivation from the advection-diffusion equation, and the key properties of the plume solution. The results are then applied to solving an inverse problem in which emission source ra...

Recently sulfolane has been detected in well water within the town of North Pole, Alaska. A plume was identified in groundwater, originating from a petroleum refinery, and the highest concentration measured in wells outside the refinery was 269 ppb as of January 2011. Due to the contamination, residents were being provided bottled water for use and additional wells were created outside the plum...

[1] The passive flux meter (PFM) measures local cumulative water and contaminant fluxes at an observation well. Conditional stochastic simulation accounting for both spatial correlation and data skewness is introduced to interpret passive flux meter observations in terms of probability distributions of discharges across control planes (transects) of wells. An estimator of the effective number o...

Methodical approaches used in the computational model “PROLOG” are given in the paper. This model is intended for assessing radiological situations and an efficiency of counter measures after short term radioactive releases. Basic local Gaussian dispersion algorithm is supplemented with modules for assessing a plume rise, dry deposition velocities, effect of buildings and complex terrain, etc. ...

The characteristics of solute transport within log-conductivity fields represented by power-law semi-variograms are investigated by an analytical Lagrangian approach that accounts for the automatic frequency cut-off induced by the initial contaminant plume size. The transport process anomaly is critically controlled by the magnitude of the Péclet number. Interestingly enough, unlike the case of...