gold mine tailings
Chinese mystery snails
legacy of arsenic and mercury contamination.
Note: We are
continuing this research in 2021-2022. If you are interested in
potential applications of our research, joining our research group
or would like to contribute to our data analyses, please email Dr. Linda Campbell.
Waste materials ("tailings") from mining activities which took
place in the 1800's can remain contaminated and toxic even over
100 years later. This is a national and international issue.
The DEEHR group is developing biomonitoring and remediation
approaches for impacts of those tailings on freshwater ecosystems
and organisms which rely on those freshwater resources. Our focus is
on Nova Scotia legacy gold mine tailings, and our goals are to
develop methodology which can be used to remediate not only those
sites but can also be applied to similar impacted sites around the
Scotia has a long history of gold mining going back to the
mid-1800's. There are over 360 gold mines in 64 historic
gold mining districts in the Cambro-Ordovician Meguma Supergroup,
stretching over a 300-km length of NS. Between 1862 and the
mid-1940's, 1.2 million troy ounces of gold were extracted,
typically using mercury amalgamation techniques. Due to a lack of
environmental regulations in the 1800's, there is a modern legacy of
three million tonnes of finely-ground contaminated waste tailings.
arsenic remain elevated and of concern even 100 years later. Mercury-recovery
were practiced, but frequently 10 to 25% of mercury was lost to the
environment through various means at each ore processing site. It
has been conservatively estimated that a total of 3.7 to 9.1 tonnes
of mercury may have been released to the NS environment from the
1850's to the 1940's. Since the original ore also included
arsenopyrite and other arsenic-bearing pyrites, the gold-mine
tailings also contain elevated arsenic. After processing, untreated
tailings were frequently slurried into nearby freshwater systems
without regard for the consequences. The legacy of localized tailing
wastes near freshwater sites in 64 gold-mine regions has resulted in
multi-generational chronic exposure to mercury, arsenic and other
toxic elements for wildlife and humans. Many sites across Nova
Scotia still bear the visible scars of this extensive mining and
processing a century later.
We are doing
something about this major environmental issue. There has
been many excellent studies of arsenic and mercury exposure and
impact in terrestrial ecosystems and geology. However, there is a
significant knowledge gap for aquatic ecosystems of Nova Scotia,
with only a few publications and reports on this topic.
The DEEHR team is carrying out several investigations looking at
this significant environmental and industrial issue for Nova Scotia,
in collaboration with Natural Resources Canada, Nova Scotia Energy
& Mines Geosciences Branch, and many others. Projects include:
- Studying the bioaccumulation and distribution of arsenic and
mercury in living organisms across the province to assess the
potential risk of gold mine tailing wastes to aquatic
- Assessing dust, air and rain samples for mercury and arsenic
from legacy gold mine tailings, including lichen collections.
- The potential of conifer
dendrochronology and dendrochemistry analyses to assess
mercury and arsenic fluxes.
- Paleoecology analyses of sediment cores for impacts of tailing
- Establishing ecotoxicology testing of key species in the
laboratory to examine the rate of bioaccumulation, speciation,
reduced functionality and lethality of the toxic tailings.
- Developing a low-cost additive and capping methods to
potentially significantly reduce the risk and toxicity of toxic
gold mine tailings to terrestrial and aquatic biota as well as
- Using remote sensing, LiDAR and other tools to create spatial
databases of the extent and distribution of legacy gold mine
tailings in Nova Scotia.
- Rephotography project using historical photographs to assess
changes through time since 1860's.
- Brochure about contaminated historical gold mine tailing
issues in Nova Scotia created by Peter Opra. Link to PDF
file. (Created as a part of Clean Youth Internship
- Dr. Emily Chapman's seminar on low-dose selenium additives for
reducing toxicity of gold mine tailing waste to earthworms. Link
- Molly LeBlanc's Three Minute Thesis talk "Not All That
Glitters: Assessing Environmental Effects of Abandoned Gold
You-tube video. PDF
- EEV Chapman, C Moore & LM Campbell. 2020. Evaluation of a
nanoscale zero-valent iron amendment as a potential tool to
reduce mobility, toxicity, and bioaccumulation of arsenic and
mercury from wetland sediments. Environmental Science and
Pollution Research. Published online. https://doi.org/10.1007/s11356-020-08347-6.
Read online: https://rdcu.be/b3cNZ.
- ME LeBlanc, MB Parsons, EEV Chapman & LM Campbell. 2020.
Review of Ecological Mercury and Arsenic Bioaccumulation within
Historical Gold Mining Districts of Nova Scotia. Environmental
Uncorrected proofs (PDF).
CBC article about the review paper. Link.
- EEV Chapman, J Robinson, J Berry & LM Campbell. 2016. Can
a low-dose selenium (Se) additive reduce environmental risks of
mercury (Hg) and arsenic (As) in old gold mine tailings? Water,
Air, & Soil Pollution. https://doi.org/10.1007/s11270-016-2909-9
Read online for free: http://rdcu.be/mFfT.
- EEV Chapman, C Moore & LM Campbell. 2019. Native plants
for revegetation of mercury and arsenic-contaminated historical
mining waste - Can a low-dose selenium additive improve seedling
growth and decrease contaminant bioaccumulation? Water,
Air, & Soil Pollution.
online for free: https://rdcu.be/bP9M7.
- Molly LeBlanc. 2019. MSc Thesis. "Bioaccumulation and transfer
of mercury and arsenic in aquatic invertebrates and emergent
insects at historical gold mine tailing sites of Nova Scotia" Link
to download page.
- Michael Smith, Linda Campbell & Carrie Rickwood. 2020.
Lichens as biomonitors of dust and air quality biomonitors at a
contaminated site. Research Proposal Poster. Saint Mary's
University. Figshare. https://doi.org/10.6084/m9.figshare.12086661.v1.
- Michael Smith et al. 2020. Maps of sampling grids. Lichens as
dust and air-quality biomonitors at a gold mine tailings site in
Nova Scotia, Canada. Figshare. https://doi.org/10.6084/m9.figshare.12086205.v1.
- Gold: A Nova Scotia Treasure. Comprehensive website resource.
- Nova Scotia Archives "Men in the Mines: A History of Mining
Activity in Nova Scotia, 1720-1992". Link.
- Nova Scotia DNR Geoscience & Mine Branch Maps, Reports
& Data. Link.
- NovaScan Portal. Link.
- Dr. Michael Parsons et al. 2012. Environmental geochemistry of
tailings, sediments and surface waters collected from 14
historical gold mining districts in Nova Scotia. Geological
Survey of Canada. Link
PDF of Open File 7150 (note: large document, 326 pages).
- John Drage. 2015. NS DNR Open File. Review of Environmental
Impacts of Historic Gold Mine Tailings in Nova Scotia. ME
2015-004. PDF Link.
- Dr. Michael Parsons's Atlantic Geoscience Society presentation
on Youtube: "Gold
Mining in Nova Scotia: Learning from the Past to Improve
Future Environmental Performance". June 2020. (no
captions, auto-captions are reasonable with several errors.)
- NS DNR Gold District GIS Data from E.R. Faribault (1898 -
1919) maps. Eastern
- What do gold mine tailings look like? (PDF file from NS
Environment). Link to PDF.
- HRM Advisory for Barry's Run, Dartmouth NS & legacy gold
mine tailings from Montague. Halifax
Regional Municipality informational website.
- Dillon Consultants. 2019. Halifax Regional Municipality Phase
I/II Environmental Site Assessment Port Wallace, Dartmouth, Nova
PDF file (large document over 600 pages).
- NS Government NS Lands Inc - Request for Proposals Tender
MINE SITES MONTAGUE AND GOLDENVILLE - For Closure Concepts and
Costs". Tender ID NSLAND97 (September 2018. Large
document! 873 pages.)
- Intrinsik Corp et al. 2019. Conceptual
Closure Plan for the Historic Goldenville Tailings Area.
July 24, 2019. Large document (762 pages).
- Intrinsik Corp et al. 2019. Conceptual
Closure Study for the Historic Montague Mine Tailings Areas.
July 24, 2019. Large document (745 pages).
- NS Lands & Forests and NS Lands Inc. NS mining site
clean-up priority list (as of March 11, 2020). PDF.
- Historical documents associated with keywords "nova scotia
gold" via the Internet
- CBC news article about Genome
Atlantic-funded project investigating microbial
metagenomics and sediment trends. Link.
- Port Wallace development & Montague legacy gold mine
tailings. Halifax Examiner article by Joan Baxter. Link.
- CBC news article about Molly LeBlanc's review paper on As
& Hg bioaccumulation in biological organisms in NS. Link.
- CBC News article about the Conceptual Closure plans for
Goldenville and Montague. Link.
- 95.7 interview by Katie Hartai with Dr.
Chapman about developing an approach for remediation with local
- CBC News article about the NS Lands Inc RFP for Montague and
Goldenville and Dr. Campbell's input: Link.
- Halifax Examiner article by Joan Baxter about legacy gold mine
tailings in Nova Scotia: Link.
- CBC News article about the Public Service Announcement re:
Barry's Run, Dartmouth and legacy gold mine tailings from