SAMMS: The Subarctic Metal Mobility StudyTuesday, November 20, 2018 - 09:00 to 09:19 Theatre 2
AUTHOR Jasiak needs to move to before Leathers
SAMMS, supported by the Global Water Futures program, is a new research initiative. SAMMS aims to identify, quantify, and predict mobility of natural source and legacy mine-source metals in soil, wetlands, and lake sediments that extend from former, present, and planned mine sites currently and as climate change alters the quantity and quality of dissolved organic matter (DOM) produced and exported from vast organic stores in subarctic NWT watersheds. Special focus is to quantify the current and future mobility of legacy atmospheric-source contaminants, above naturally occurring levels, from the Giant Mine. Six work plans have been developed. These are designed to comprehensively trace the transport and behaviour of DOM and metals through terrestrial and aquatic ecosystems in headwater catchments between Giant Mine and Whati. Work plans include: 1) terrestrial stores of historical metal deposition and transport to aquatic ecosystems, 2) DOM quantity and quality, metal binding, and toxicology, 3) modelling of DOM quantity and quality in cold regions, 4) metal depositional history, pathways, and processes in lake sediments, 5) paleo-ecotoxicology and ecosystem structure, and 6) climate change effects including permafrost thaw. Findings will inform improved decision-making by multiple stakeholders in the NWT, including Indigenous peoples, about the both legacy of mining activities and implications of new mining developments on water quality in a changing environment.
This presentation will provide an introduction to SAMMS and highlight summer 2018 fieldwork activities, early results and describe our planned research direction over the next 12 to 24 months. Current research includes: 1) sediment cores collected in June within the annual regional prevailing airshed from Giant Mine from lakes each 10km along an 80km transect extending northwest. Analysis of these lake sediment cores will aid in systematic identification of the extent of far-field atmospheric emissions of arsenic from Giant Mine. Paleohydrological analyses will be used to explore the role of climate on metal deposition in the lakes. 2) Fieldwork was also conducted at lakes northwest of Yellowknife along Highway 3, and included collection of lake sediment cores as well as soil, snow and lake water samples. Metal concentration and radiometric dating results from a sediment core retrieved from ‘Lake 10’, located 57 km northwest of Yellowknife, displays down-core enrichment in arsenic (and antimony) concentration, consistent with some of our prior lake sediment core results adding further evidence for far-field emissions from Giant Mine. ‘Lake 10’ is readily accessible from Highway 3 and will serve as a key intensive site to launch additional SAMMS terrestrial and aquatic ecosystem research.