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Acid mine drainage (AMD), which is primarily caused by the exposure of sulfidic minerals to oxygen and water during mining operations, remains a significant contributor to environmental pollution. Numerous technologies have been developed to prevent/control and treat AMD, including the isolation of waste from the atmosphere and treatment systems for AMD-impacted water. Many field studies on mine site reclamation have involved an individual AMD source and/or technology, with a limited number of studies looking at reclamation programs integrating multiple approaches to manage AMD stemming from both surface and underground sources. The former Franklin mine site in Nova Scotia, Canada, was impacted by the deposition of waste rock across the site and the discharge of mine water from underground workings, with the adjacent Sullivan’s Pond serving as the main environmental receptor. Site reclamation was completed in 2010 and involved the following: (1) excavation of the dispersed waste rock (117,000 m²) and backfilling with clean soil; (2) consolidation of the excavated waste rock into a covered, compact waste rock pile (WRP) (25,000 m²); and (3) construction of a passive treatment system for the discharging underground mine water. An extensive field sampling program was conducted between 2011 and 2018 to monitor a range of meteorological, cover material, waste rock, groundwater, and surface water quality parameters. The results confirm that the multi-layer, geomembrane-lined WRP cover system is an extremely effective barrier to air and water influx, thereby minimizing the rate of AMD generation and seepage into groundwater and eliminating all contaminated surface water runoff. A small AMD groundwater plume emanates from the base of the WRP, with 50% captured by the underground mine workings over the long term and 50% slowly migrating towards Sullivan’s Pond. Excavation of the former waste disposal area eliminated the AMD source from the previously dispersed waste, with only clean surface water runoff and a diminishing legacy groundwater plume remaining. Finally, the passive treatment system, which contains a series of treatment technologies such as a limestone leach bed and settling pond, successfully treats all mine water loading (~50 kg/day) discharging from the underground workings and surface runoff. Its additional treatment capacity (up to ~150 kg/day) ensures it will be able to manage any potential drop in treatment efficiency and/or increased AMD loading from long-term WRP seepage. This comprehensive study of mine site reclamation and AMD management at an abandoned mining site can be of great reference value for environmental management and policymakers in the mining sector. Full article

While many sources of contamination in chemical and biological laboratories are well understood and known, some are less so. To quantify the magnitude of the potential contamination of solutions by zinc in common laboratory syringes, a study was conducted on solutions stored in rubber-containing syringes in which the rubber was catalyzed by zinc. This study identified specific factors contributing to contamination from laboratory syringes, including the syringe brand, time, solution type, and pH. Two common syringe brands, Covidien and BD, were tested, and three time durations, 0 days, 1 day, and 14 days, were examined. The solutions tested included sucrose and tartaric acid, representing both covalent and ionic species. Additionally, this study employed a pH range of 2 to 13 to further explore zinc contamination across a wide range of conditions and factors. The zinc concentration from the syringes was measured using inductively coupled plasma mass spectrometry (ICP-MS). The results, which ranged from less than 20 to over 600 μg L⁻¹, revealed increased zinc concentration at both extreme pH values, while remaining lower but measurable at neutral pH levels. Zinc contamination is important to study because its contamination in laboratory syringes could interfere with the detection of other elements, further skew laboratory data, unexpectedly catalyze reactions, and lead to inconsistencies in experimental conditions. This study further emphasizes the broader significance of understanding pollutants within laboratory settings. The findings highlight the intricate dynamics of zinc contamination, stressing the need for the control of environmental factors and the broad dissemination of lesser-known sources. Recognizing the potential impact of contaminants like zinc is crucial, as it not only influences analytical accuracy, but also mirrors the wider concern of pollutants compromising scientific integrity in diverse experimental conditions. Full article

Anthropogenic chemicals are fundamental for maintaining our standard of living in modern society. Unfortunately, some chemicals are persistent and can enter waste streams and, ultimately, the environment. Commonly used household products, including pharmaceuticals and personal care products, are notable sources of contaminants. The aim of this study was to develop an ‘Up-the-Pipe Solutions’ framework to raise awareness within the wider community about the presence and potential risks of the chemicals found in household products. There is potential to reduce the levels of contaminants in waste streams or substitute them with less harmful alternatives by raising awareness. This framework is based on ‘The Natural Step’ and the concept of essentiality; it recognises the importance of engaging with communities to raise awareness of each individual’s contribution to the problem. Our daily activities and behavioural patterns can have adverse consequences, including the release of persistent contaminants in main waste streams from our kitchens, bathrooms, and green wastes. The ‘Up-the-Pipe Solutions’ framework was successfully used in a small community to engage with school children, local authorities, and Māori leaders to raise awareness of chemical pollution. Full article