Copper In Groundwater Research Articles

Influence of Rainfall Seasonality in Groundwater Chemistry at Western Region of São Paulo State—Brazil

The present study evaluated the spatiotemporal variation in concentration of cadmium, lead and copper ions in groundwater wells in the stratigraphic subdivision “Santo Anastácio” that belongs to the Bauru aquifer system in the western region of São Paulo State. Exploratory statistics methods were employed to investigate the response of the concentration of these metals in the aquifer through the pluviometric index of the region. The results show a direct dependence of the mean monthly flow of the metals in the groundwaters to the monthly rainfall flow. The observed behavior was cyclic with a gradual increase and decrease in the flow throughout time. Two groups of cyclic variation were identified. The seasonality of the mean monthly flow of Cd2+ and Pb2+ was inversely proportional to the magnitude of the pluviometric index of the region studied. Meanwhile, the seasonality of Cu2+ was directly correlated to the seasonable rainfall variability. These behaviors lead us to point out that cadmium and lead come from minerals present in the aquifer itself and the presence of copper in groundwater is associated with an anthropogenic action due to the region’s agricultural activity. The study helps us better comprehend the behavior of the whole groundwater system through a comparison with temporal hydrogeochemistry.

Laboratory study of interactions between copper and microorganisms in oxic groundwater

The interactions between copper, the canister material in the nuclear waste disposal concept in Finland and Sweden, and micro-organisms in groundwater in their expected near-field environment are the core interest of this paper. Copper specimens were incubated with ammonia-oxidising bacteria for different time periods and then subjected to electrochemical measurements and surface characterisation to provide data on biofilm formation and its effects on copper corrosion. The biofilms on the surface of copper specimens were heterogeneous, due to the morphology of corrosion products that developed during the biofilm growth phase, but they also contributed to the nature and amount of corrosion product layers on the copper surfaces. Nitrogen was systematically detected in the biofilm specimens, due to the presence of ammonia-oxidising bacteria. The electrochemical response of the specimens was so heavily linked with the detected corrosion products, often rich in chlorine from the groundwater, that the influence of ammonia-oxidising bacteria was masked. The results demonstrate that the role that biofilm formation plays in the corrosion of copper in groundwater environment is very difficult to predict even under controlled laboratory conditions.

Assessing the efficiency of a coastal Managed Aquifer Recharge (MAR) system in Cyprus

Managed Aquifer Recharge (MAR) is becoming an attractive water management option, with more than 223 sites operating in European countries. The quality of the produced water, available for drinking or irrigation processes is strongly depended on the aquifer's hydrogeochemical characteristics and on the MAR system design and operation. The objective of this project is the assessment of the operation efficiency of a MAR system in Cyprus. The coupling of alternative methodologies is used such as water quality monitoring, micro-scale sediment sorption experiments, simulation of groundwater flow and phosphate and copper transport in the subsurface using the FEFLOW model and evaluation of the observed change in the chemical composition of water due to mixing using the geochemical model PHREEQC. The above methodology is tested in the Ezousa MAR project in Cyprus, where treated effluent from the Paphos Waste Water Treatment Plant, is recharged into the aquifer through five sets of artificial ponds along the riverbed. Additionally, groundwater is pumped for irrigation purposes from wells located nearby. A slight attenuation of nutrients is observed, whereas copper in groundwater is overcoming the EPA standards. The FEFLOW simulations reveal no effective mixing in some intermediate infiltration ponds, which is validated by the inverse modeling simulation of the PHREEQC model. Based on the results, better control of the infiltration capacity of some of the ponds and increased travel times are some suggestions that could improve the efficiency of the system.

EIS study on aerobic corrosion of copper in ground water: influence of micro-organisms

The nuclear waste disposal concept in Finland and Sweden is based on a multi-barrier system, where the solid spent fuel is placed in a cast iron container that is further enclosed in a copper canister. The copper canisters will be placed vertically in holes drilled in a deep bedrock which are then filled with a bentonite clay. The near-field environment of bentonite clay and groundwater is then expected to maintain integrity of the copper canisters for at least 100 000 years. The ground water at the final disposal depth contains micro-organisms with a vast metabolic potential, and it is known that micro-organisms may induce or accelerate the corrosion of metals. Therefore, it is of vital importance to understand the surface interactions of copper and the expected near-field environment. In this study, the results from two types of experiments that investigate the corrosion of copper in oxic ground water environment with and without micro-organisms and electrochemical impedance spectroscopy (EIS) as one of the key research methods are reported. First, long-term immersion experiments with a range of in-situ electrochemical measurements were designed to simulate the initial oxic stage of the deep geological nuclear waste repository in the presence of bentonite. Second, electrochemical laboratory tests were planned to improve understanding on the interactions between copper and the micro-organisms in ground water environment: copper specimens were incubated with micro-organisms for different time periods and then subjected to electrochemical measurements to provide data. The results collected from these two test series are reported and discussed here by focusing on the EIS data and its role in interpreting the surface processes. It is evident that EIS helps in understanding the influence of micro-organisms on the copper degradation process.

Quality of Groundwater in an Area with Intensive Agricultural Activity

The main objectives of this study were the application of principal component analysis (PCA) for variable selection of an aquifer with a large amount of data record and assessment of the overall quality and the extent of groundwater contamination in Andimeshk, Iran. For this purpose, 17 groundwater quality variables in 46 sampling wells and springs during an eight-year time period (2006–2013) were considered. A PCA was conducted for dry and wet seasons to find out associations between variables, thus reducing the dimensionality of the data. PCA resulted in the reduction of original data to nine variables in wet season encompassing 94.35 % of the total variance and eight variables in dry season accounting for 92.03 % of the total variance. A Procrustes Analysis on the reduced data set showed a high similarity between the original and reduced variables. Groundwater quality index indicated that the most polluted parts of the study area are located in areas of intensive agricultural activities. The results of water quality proved that the effect of geological formations on groundwater quality is mainly due to the influence of EC in terms of TDS, Mg, Ca, Sulfate, and Cu rather than other parameters. The application of animal manure at excessively high rates or the combined application of high rates of manure and nitrogen fertilizer has increased nitrate levels in recent years. Fertilizers may also have an impact on the levels of copper in ground water as it is one of the impurities in these inorganic fertilizers.

Corrosion inhibition by benzotriazole derivatives and sodium dodecyl sulphate as corrosion inhibitors for copper in ground water at different temperatures

1‐(2‐Pyrrole carbonyl) benzotriazole (PBTA) and 1‐(2‐thienyl carbonyl)‐benzotriazole (TBTA) were synthesized. Different concentrations of PBTA, TBTA, sodium dodecyl sulphate (SDS), and molybdate (Mo) were evaluated as corrosion inhibitors for copper in ground water medium at different temperatures. The obtained results were compared with the effect of benzotriazole (BTA) on the inhibition of copper corrosion at the same condition. The study was performed using potentiodynamic polarization, electrochemical impedance spectroscopy, cyclic voltammetry, and scanning electron microscopy investigations. A good inhibition is ensured at elevated temperatures. All measurements indicated that PBTA, TBTA, and BTA act as good corrosion inhibitors and their inhibition efficiency (IE%) increased with combining them with optimum concentration of SDS and Mo. Furthermore, the best performance was recorded for the compound PBTA + SDS + Mo, which was found to offer increased IE% in a synergistic manner, thereby acting as a good corrosion inhibitor for copper in ground water medium. Copyright © 2015 John Wiley & Sons, Ltd.

Source, transport, and fate of rhenium, selenium, molybdenum, arsenic, and copper in groundwater associated with porphyry–Cu deposits, Atacama Desert, Chile

We collected groundwaters in and around a large (313 Mt at 1.08% Cu and 0.3% cutoff) undisturbed porphyry copper deposit (Spence) in the hyperarid Atacama Desert of northern Chile, which is buried beneath 30–180 m of Miocene piedmont gravels. Groundwaters within and down-flow of the Spence deposit have elevated Se (up to 800 μg/l), Re (up to 31 μg/l), Mo (up to 475 μg/l) and As (up to 278 μg/l) concentrations compared to up-flow waters (interpreted to represent regional groundwater flow). In contrast, Cu is only elevated (up to 2036 μg/l) in groundwaters recovered from within the deposit; Cu concentrations are low down gradient of the deposit. The differential behavior of the metals/metalloids occurs because the former group dissolves as anions, enhancing their mobility, whereas the base metals dissolve as cations and are lost from solution most likely through adsorption to clay surface exchange sites and through formation of secondary copper chlorides, carbonates, and oxides. Most groundwaters within and down-flow of the deposit have Eh–pH values around the Fe II/Fe III phase boundary, limiting the impact of Fe-oxyhydroxides on oxyanions mobility. Se, Re, Mo, and As are all mobile (with filtered/unfiltered samples ∼ 1) to the limit of sampling 2 km down gradient from the deposit. The increase in ore-related metals, metalloids, and sulfate and decrease in sulfate–S isotope ratios (from values similar to regional salars, + 4 to + 8‰ δ 34S CDT to lower values closer to hypogene sulfides, + 1 to + 4‰ δ 34S CDT) is consistent with active water–rock reactions between saline groundwaters and the Spence deposit. It is likely that hypogene and/or supergene sulfides are being oxidized under the present groundwater conditions and mineral saturation calculations suggest that secondary copper minerals (antlerite, atacamite, malachite) may also be actively forming, suggesting that supergene and exotic copper mineralization is possible even under the present hyperarid climate of the Atacama Desert.