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This study aimed to synthesise and interpret stable isotopic data (δ2H and δ18O) from various sources to understand the isotope hydrology around coal mine operations in Elk Valley, B.C., Canada. The data, including precipitation, groundwaters, seeps, and mine rock drains, were used to construct a local meteoric water line (LMWL) for the Elk Valley, evaluate the spatiotemporal isotopic composition of its groundwater, and assess mine seepage and mine rock drain discharge. The study revealed a robust LMWL relation (δ2H = 7.4 ± 0.2 · δ18O – 4.3 ± 4.1). The groundwater and seep data indicated a winter season bias and a north–south latitudinal gradient, suggesting rapid near-surface groundwater flow without significant post-precipitation evaporation. Porewater isotope samples from unsaturated mine rock piles (MRPs) showed site-specific evaporation patterns, potentially due to convective air flows or exothermic sulphide oxidation. This research revealed the influence of groundwater and meltwater on rock drain discharge. Based on evaporative mass balance calculations, MRPs seasonally contributed ca. 5 %(December base flow) and 22 % (snowmelt) to drain discharge. The findings underscore the value of stable isotope data collections in the Elk Valley to help better define and quantify the hydrology–hydrogeology, including a better understanding of evaporative conditions in MRPs. [ABSTRACT FROM AUTHOR]

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This article analyzes how US nonproliferation policies that sought to curtail US exports of highly enriched uranium (HEU) affected Canada's medical-isotope industry and, particularly, the Canadian MAPLE (Multipurpose Applied Physics Lattice Experiment) reactors project. US HEU-export policies established between 1978 and 2012 highlight the "nuclear ambivalence" of the Canadian isotope industry's flagship product, molybdenum-99 (Mo-99)—a life-saving commodity widely used by US hospitals but also a material whose production process, based on HEU, came to be perceived as a potential threat to US and world security. The ambivalent status of Mo-99 production was reinforced by a state of mutual dependence between the two countries: On the one hand, Canada depended entirely on US HEU exports to maintain its dominant position in the Mo-99 world market and could not turn to other sources of HEU supply. On the other hand, US hospitals relied mainly on Mo-99 of Canadian origin, which limited the US government's ability to enforce its policy by suspending its HEU exports to Canada. As a result, US and Canadian efforts to convert the Canadian isotope facilities to low-enriched uranium were thwarted by tensions between global security, public health, and commercial stakes, which led ultimately to ending Canada's Mo-99 production. [ABSTRACT FROM AUTHOR]

A method based on isotope dilution headspace solid-phase microextraction and gas chromatography/mass spectrometry was used to assess levels of bisphenol A (BPA) in 56 samples of bottled water products sold in Canada. Levels of BPA in samples of all 51 non-polycarbonate (PC) bottled water products were lower than the method detection limit (0.50 µg l-1). Levels of BPA in most bottled water products in PC carboys were low, ranging from <0.50 to 1.4 µg l-1 with an average of 0.75 µg l-1. However, BPA was detected at levels of 8.8 and 6.5 µg l-1 in two bottles of the bottled water products in PC carboys from the same product analysed over a 5-week period, likely due to accidental or careless exposure of the products to heat (e.g. under the sun) during storage and/or transportation for extended periods of time. [ABSTRACT FROM AUTHOR]

Monitoring of stable water isotopes ( 18 O and 2 H) in precipitation and surface waters in the Mackenzie River basin of northern Canada has created new opportunities for researchers to study the complex hydrology and hydroclimatology of this remote region [1]. A number of prior studies have used stable isotope data to investigate aspects of the hydrological regime of the wetland-dominated terrain near Fort Simpson, Northwest Territories, Canada [2, 3]. The present paper compares estimates of groundwater contributions to streamflow derived using the WATFLOOD distributed hydrological model, equipped with a new water isotope tracer module, with the results of conventional isotope hydrograph separation [4] for five wetland-dominated catchments along the lower Liard River. The comparison reveals highly promising agreement, verifying that the hydrological model is simulating groundwater flow contributions to total streamflow with reasonable fidelity, especially during the crucial snowmelt period. Sensitivity analysis of the WATFLOOD simulations also reveals intriguing features about runoff generation from channelized fens, which may contribute less to streamflow than previously thought. [ABSTRACT FROM AUTHOR]

The article provides information on studies of elemental synthesis in exploding stars using the Detector of Recoils And Gammas Of Nuclear reactions (DRAGON) and the TRIUMF UK Detector Array (TUDA). The goal of the DRAGON experimental program, which is based at the ISAC Radioactive Beams facility in Canada, is to study the probability of reactions involving the capture of hydrogen or helium by a short lived exotic isotope, which results in the emission of electromagnetic radiation only.