An investigation of primary water sources in two Bolivian basins identified the presence of heavy metals toxic to health that exceeded the permissible limits for drinking water. Lead deposited in the San Jacinto and Huacata–Tarija reservoirs within the Guadalquivir basin and arsenic in the Milluni–La Paz basin were identified. The work studies reverse osmosis (RO) to remove Pb and As. The main contribution of this research is the development and construction of a mathematical model based on the Spiegler–Kedem concentration polarization model using different concentrations of Pb and As. The model makes it possible to design high conversion facilities (>80%) and optimize the process from the point of view of energy efficiency in future works. The model was developed to also include an Arrhenius temperature adjustment factor that allows for an accurate prediction of the process performance. The experimentation was carried out in two RO pilot plants using polyamide membranes. The model fits correctly with a maximum relative error between the experimental and theoretical flows of 5.4% and 4.4%. Among the benefits of the study, it guarantees the rejection of metals greater than 99%, even at low pressures.

Like other Latin American countries, Bolivia is in the race towards development, which has caused many economic activities to be carried out without due consideration for the care of the environment. At this point, it is essential to carry out environmental inventories to preserve the quality of ecosystems and natural resources, such as water. As water is vital, it needs to be adequately monitored and managed to prevent its degradation. This research presents the results of monitoring the main sources of water supply in two continuously growing departments of Bolivia, La Paz, and Tarija. The main objective of this study was to evaluate the suitability of the water to which the population has access, with particular attention to heavy metals with concentrations that exceed the permitted limits. The metals found were arsenic, chromium, mercury, manganese, iron, zinc, and tin in the Milluni area, and lead, iron, and manganese in the Guadalquivir area. Exposing the presence of metals in water sources implies immediate attention by decision-makers to take action to reduce the risk to public health. In addition, this study exposes a Bolivian reality that could encourage other countries in similar contexts to conduct similar studies on their water sources.

Bolivia is among the countries with the highest availability of freshwater globally. However, many of its natural sources are impacted by anthropogenic activities, such as mining. Water is intimately linked to public health and is essential to achieving sustainable development. It is necessary to preserve water resources by designing and validating monitoring programs that help control the quality of the sources that supply important population centers. The study area in this research is the upper part of the Milluni micro-basin, whose lagoon system supplies water for two large cities. Milluni is close to illegal and abandoned mining areas, making the region highly vulnerable to heavy metal contamination. This study aimed to optimize the resources available for monitoring Milluni. The frequency of monitoring was statistically determined, and the correlation between parameters measured in situ (pH and conductivity) and metal ion concentrations to determine low-cost indicators to monitor the presence of heavy metals. A multivariate analysis of friction of the results of the pilot year of the monitoring program designed for Milluni, considering the characteristics and economic limitations, is presented. An approximation of the quality of the surface water resources of Milluni is presented as a result of the monitoring operations.

Nowadays, stricter control and rigorous landfill standards are being promoted in industries that produce liquid discharges into the environment. The development of innovative and sustainable technologies to remove lead from water is of great importance in all aspects, with safe recycling practices, especially with high lead concentrations, such as in mining activities. The experiment was conducted at a reverse osmosis (RO) pilot plant, operated at low impact pressures and designed to optimize energy savings without compromising separation efficiency. By reducing energy consumption, the process not only lowers operational costs but also minimizes the environmental impact associated with high energy consumption. The results show that RO operated at low pressures successfully removed 99.75% of lead at a pressure of 10 bar and a flux of 67.44 L/m²·h, demonstrating a practical and sustainable solution for lead removal at pressures of 5, 7.5, and 10 bar, which are considered low pressures since they are below 1.0 MPa. In addition to its high removal efficiency, the process offers significant advantages in terms of energy efficiency and a reduced carbon footprint. Enhancing the efficiency of this technology is crucial, not only to decrease operational costs but also to reduce environmental impact.

One of the factors with the most significant impact due to pollution caused by mining activities is water. Surface water resources are limited, and in many cases, they are the primary water source for consumption; thus, its quality is a fundamental subject of study. The traditional way of studying water quality is to measure parameters and compare the results with tables of values established in the regulations. The quality of drinking water is characterized and controlled. However, this traditional comparison method may be subjective and insufficient to classify water quality as safe. Therefore, it is necessary to develop and complement the conventional monitoring, linking physicochemical analysis with remote perception. The different variables analyzed can be integrated and result in much more complete water quality indices, achieving the evolution of the monitoring programs of the water quality of the surface bodies. This research combines remote sensing with traditional monitoring to obtain a more robust and affordable indicator, resulting in a study of the central water bodies of Milluni. The main finding—the alarming contamination in the Milluni Chico and Milluni Grande lagoons—provides more accurate information to decision-makers to improve water management in Bolivia.

An effective alternative for water purification is reverse osmosis (RO). Laboratory-scale RO modeling is widely applied worldwide, and allows the evaluation of the behavior of the system to find the most convenient operating variables to be applied in future industrial scale-ups. Statistical models provide a wide range of information that allows a statistical prediction of the operation of the plant, and allows us to obtain efficiency indices in its development; these are useful in the planning, operation and monitoring process in RO plants. The mathematical models describe the physical behavior of the membrane and allow the identification of optimal operating conditions, taking into account economic aspects, guaranteeing a greater implementation of RO technology in developing countries which have problems with water contaminated with toxic heavy metals. The present work shows a review of different statistical and mathematical models, and the suitability of these in the analysis of RO in the separation of heavy metals in drinking water that can be applied in countries with serious environmental problems. Bolivia and several river basins, such as the Guadalquivir and Milluni, present this type of problem. A comparative method is proposed to establish the advantages and selection criteria to apply the different models in RO.