GEOL/ENVS Graduate Student Seminars - HSH 336 @ 4pm
4:00 pm – 4:25 pm Ben Gooley: Environmental Implications of Ore Processing and Mercury Amalgamation at Legacy Nova Scotia Gold Districts.
Historical artisanal and small-scale gold mining (ASGM) in Nova Scotia has resulted in widespread legacy contamination by mercury (Hg) and arsenic (As). Between 1860 and 1950, a total of 64 gold districts were established across the province. During this period, mine tailings—the primary waste product of ASGM—were commonly deposited directly into wetlands, lakes, rivers, and coastal environments. These tailings contain elevated concentrations of toxic metal(loid)s, As and Hg. Arsenic is naturally hosted within sulfide minerals, such as arsenopyrite, which are associated with high-grade auriferous quartz veins, whereas elemental Hg was intentionally introduced during the amalgamation process used to recover gold. Examining the speciation of As and Hg in the environment is particularly important when assessing the inherent risk of these contaminants; inorganic forms of As (As(III) and As(V)) and organomercury compounds such as methylmercury (MeHg) are the most toxic and bioavailable to aquatic organisms, making them the most environmentally relevant species: a distinction critical for risk assessment. Weathering and erosion of mine tailings can mobilize Hg and As into surrounding environments, facilitating their entry into aquatic food webs where they may bioaccumulate and, in the case of MeHg, biomagnify, posing potential risks to ecosystems, wildlife, and humans. This seminar will critically examine the current methodologies for determining environmental risk across Nova Scotia’s legacy goldmining districts and identify knowledge gaps in peer-reviewed research, with a focus on the interconnectivity between environmental impact and human health.
4:30 pm – 4:55 pm Bella MacQuarrie: A critical evaluation of managed retreat as a climate change adaptation technique in Nova Scotia provincial parks
Climate change is intensifying coastal hazards through processes such as relative sea-level rise, loss of protective sea ice, and increased storm intensity. Together, these changes are accelerating coastal erosion, increasing the frequency of flooding, and heightening risks to coastal infrastructure. Traditional coastal adaptation strategies have focused on hard engineering and structural modifications such as seawalls, revetments, and flood-resistant construction. However, these methods often require ongoing maintenance and
may lead to long-term adverse environmental impacts. Managed retreat has emerged as an alternative climate adaptation strategy that reduces risk by relocating infrastructure away from hazard-prone coastal areas, allowing natural coastal processes to continue.
This presentation is a critical evaluation of the application of managed retreat techniques in Nova Scotia Provincial Parks, drawing on case studies from Lawrencetown Beach Provincial Park and Rissers Beach Provincial Park. The application of managed retreat at these sites demonstrates how infrastructure realignment and relocation can reduce exposure to coastal hazards. The longer-term opportunities and challenges involved in implementing managed retreat in coastal environments will also be discussed.