Ground-Water Flow and Transport Modeling Creativity and innovation are invaluable in making sound predictions related to ground-water flow and transport. JSAI has developed ground-water flow models for many of the ground-water basins in New Mexico, and gained a unique understanding of how to efficiently develop ground-water flow models that best represent the hydrogeologic conditions. One of JSAI's specialties is advanced analysis of pumping tests, using both conventional analytical procedures and digital radial-flow models. John Shomaker studied under Kenneth Rushton, at the University of Birmingham, England, where the first finite-difference models for analysis of flow to a well were developed. These are similar to multi-layer regional models, like MODFLOW, but deal with radial flow into a pumping center. We use updated versions of the code published by Rushton and Redshaw (1979) and Rathod and Rushton (1991). These models provide a way of quantifying each of the influences on a wellís performance: the hydraulic conductivity and storage properties of up to three layers of the aquifer, the vertical hydraulic conductivity between layers, and the hydraulic properties of the zone invaded by drilling fluid, the gravel pack (if any), and the casing perforations, for evaluation of well efficiency. At JSAI, hydrogeologists also build ground-water flow models using the MODFLOW code with software such as Visual Modflow and Ground Water Vistas. A few examples of JSAI's experience with ground-water flow and transport modeling are as follows: Regional ground-water flow model of the Mimbres Basin in Southwestern New Mexico. The model was used to evaluate the sustainability of the water treatment system associated with Chino Mines Closure Close-out. Regional ground-water flow model of the Tyrone operations of Phelps Dodge. The model was used to estimate drawdown due to pumping of wells and pumping from open-pit mines in support of water-rights applications. Ground-water flow modeling in support of a water-rights application for the Tailings Pond 7 Interceptor Well Field (M-5017-S et al.). This supporting work provided the New Mexico State Engineer the information needed to allow diversion of water from the pollution control wells. Aquifer Storage and Recovery (ASR) project for Alamogordo. JSAI developed and calibrated a ground-water flow model of the La Luz Well Field to evaluate the feasibility of utilizing ASR for optimization of supply and prevention of saline encroachment. Regional ground-water flow model in support of water-rights applications related to Cunningham Hill Mine Reclamation project, Ortiz Mine Grant, near Santa Fe, New Mexico. A transport model was also developed to simulate migration of dissolved constituents from the open-pit pool to the surrounding aquifer. The transport-model results are being used to develop alternative abatement standards for the proposed reclamation project. Ground-water flow model of the Chino Mines Company Santa Rita Pit and surrounding area to simulate effects from pumping the Princess Shaft. This model was provided as technical support for water-rights transfer to the Princess Shaft. The results of the model were accepted by the State Engineer, and the transfer was approved. Ground-water flow model of the Jornada Basin in support of water-rights applications by the City of Las Cruces. This was a calibrated multi-layer model that posed challenging hydrogeologic conditions of steep mountain-front hydraulic gradients, and flow through complicated stratigraphic sequences and bedrock structures. Ground-water flow model of the Phelps Dodge 2C and 4A leach stockpiles at Tyrone Mine. The model results were used to design leach-solution recovery strategies. Contaminant-transport model of the Canutillo, Texas area to predict contaminant exposure from a petroleum hydrocarbon plume. The model results were used in toxicological study of benzene exposure. General Contact John Shomaker & Associates, Inc. Return to top of page 2611 Broadbent Parkway NE Albuquerque, New Mexico 87107 phone 505.345.3407 fax 505.345.9920