Browsing by Author "Munoz, Jose F."

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    Integrated Water Resource Management and Energy Requirements for Water Supply in the Copiapo River Basin, Chile
    (MDPI, 2014) Suarez, Francisco; Munoz, Jose F.; Fernandez, Bonifacio; Dorsaz, Jean Marc; Hunter, Christian K.; Karavitis, Christos A.; Gironas, Jorge; CEDEUS (Chile)
    Population and industry growth in dry climates are fully tied to significant increase in water and energy demands. Because water affects many economic, social and environmental aspects, an interdisciplinary approach is needed to solve current and future water scarcity problems, and to minimize energy requirements in water production. Such a task requires integrated water modeling tools able to couple surface water and groundwater, which allow for managing complex basins where multiple stakeholders and water users face an intense competition for limited freshwater resources. This work develops an integrated water resource management model to investigate the water-energy nexus in reducing water stress in the Copiapo River basin, an arid, highly vulnerable basin in northern Chile. The model was utilized to characterize groundwater and surface water resources, and water demand and uses. Different management scenarios were evaluated to estimate future resource availability, and compared in terms of energy requirements and costs for desalinating seawater to eliminate the corresponding water deficit. Results show a basin facing a very complex future unless measures are adopted. When a 30% uniform reduction of water consumption is achieved, 70 GWh over the next 30 years are required to provide the energy needed to increase the available water through seawater desalination. In arid basins, this energy could be supplied by solar energy, thus addressing water shortage problems through integrated water resource management combined with new technologies of water production driven by renewable energy sources.
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    Transport of simazine in unsaturated sandy soil and predictions of its leaching under hypothetical field conditions
    (ELSEVIER, 2007) Suarez, Francisco; Bachmann, Jaime; Munoz, Jose F.; Ortiz, Cristian; Tyler, Scott W.; Alister, Claudio; Kogan, Marcelo
    The potential contamination of groundwater by herbicides is often controlled by processes in the vadose zone, through which herbicides travel before entering groundwater. In the vadose zone, both physical and chemical processes affect the fate and transport of herbicides, therefore it is important to represent these processes by mathematical models to predict contaminant movement. To simulate the movement of simazine, a herbicide commonly used in Chilean vineyards, batch and miscible displacement column experiments were performed on a disturbed sandy soil to quantify the primary parameters and processes of simazine transport. Chloride (Cl-) was used as a non-reactive tracer, and simazine as the reactive tracer. The Hydrus-1D model was used to estimate the parameters by inversion from the breakthrough curves of the columns and to evaluate the potential groundwater contamination in a sandy soil from the Casablanca Valley, Chile. The two-site, chemical non-equilibrium model was observed to best represent the experimental results of the miscible displacement experiments in laboratory soil columns. Predictions of transport under hypothetical field conditions using the same soil from the column experiments were made for 40 years by applying herbicide during the first 20 years, and then halting the application and considering different rates of groundwater recharge. For recharge rates smaller than 84 mm year(-1), the predicted concentration of simazine at a depth of I m is below the U.S. EPA's maximum contaminant levels (4 mu g L-1). After eight years of application at a groundwater recharge rate of 180 mm year I (approximately 50% of the annual rainfall), simazine was found to reach the groundwater (located at 1 m depth) at a higher concentration (more than 40 mu g L-1) than the existing guidelines in the USA and Europe. (c) 2007 Elsevier B.V.. All rights reserved.