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Contaminated Sites
in the Northwest Territories, 2006
April 2, 2006
Information initially (October 28, 2005) produced by the
Northern Contaminated Sites Program,
Indian and Northern Affairs Canada. Updates by ExploreNorth.
Mining in the Northwest Territories
Mine Site Reclamation Policy for the Northwest Territories
Giant Mine
Yellowknife’s Giant Mine began operations in 1948 and quickly became one of Canada’s most prolific gold mines. Over its lifespan, Giant Mine
produced more than 7 million ounces of gold. This is one of three mines
that reverted back to the Crown in 1999 when the mines’ owner at the time,
Royal Oak Mines Inc., went into receivership.
Why is it a contaminated site?
The main issue at Giant Mine is the 237,000 tonnes of arsenic trioxide dust stored underground at the
site. The dust was created during the gold production process. When the mined ore was roasted to release the gold, the arsenic was also released
as arsenic trioxide dust. This highly toxic dust continues to be safely stored in the 15 stopes and chambers underground at the site. The amount is
equivalent to seven and a half 11-storey office buildings. On site, there are also tailings ponds, old mine structures and other surface features
that require remediation.
What’s going on at the site?
Giant Mine is currently under care and maintenance. This means the site is secure and is being
monitored. Also, all water pumped from the mine is being collected and treated on site before being released into Baker Creek. Numerous on-site
studies are also being carried out to gather more information about the environmental conditions of the site.
Future plans
DIAND’s Giant Mine Remediation Project Team is creating a Remediation Plan for the site. This will include a plan to
freeze the underground stopes and chambers containing the arsenic
trioxide, and the surrounding rock. For more detailed information see the
Giant Mine Remediations Project website.
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Colomac Mine
Newsletter (Summer 2005)
Colomac Mine was a gold mine in operation from 1989 to 1997, located 222 kilometres northwest of Yellowknife. This is one of three mines that
reverted back to the Crown in 1999 when the mines’ owner at the time, Royal Oak Mines Inc., went into receivership.
Why is it a contaminated site?
One of the main concerns at Colomac is “tailings water”- contaminated water produced by the processing
of the gold ore. The tailings water is contaminated with cyanide, a chemical that was used to get the gold out of the ore, among other
substances. Currently, the contaminated water is safely contained in two areas, the Tailings Containment Area (TCA) and a mined-out pit known as
Zone 2 Pit. At present, both areas contain approximately 10 million cubic metres of water. However, rainfall and snowmelt will eventually fill both
the TCA and Zone 2 Pit.
What’s going on at the site?
After extensive community consultation, DIAND filed a Remediation Plan with the Mackenzie Valley
Land and Water Board on March 31, 2004. This plan recommends Enhanced Natural Removal as the best remediation option for tailings water. This
involves adding phosphorus to the contaminated water, which promotes the growth of algae. The algae breaks down cyanide and ammonia into non-toxic
substances. Measurements over the past three years have shown that this process successfully reduces contaminants, including cyanide and
ammonia.
A lot of other remediation work continues to be done at the site, including an eight-kilometre fence installed to prevent caribou and other
wildlife from entering the tailings containment area. DIAND is working in partnership on the Colomac project with the Tlicho people, who live in
the area. The site operator is Tli Cho Logistics, a Dogrib company, and the majority of the workforce are Tlicho people.
Future Plans
Once the new water licence and land-use permit are issued, implementation of the large remediation tasks can begin.
Remediation of the entire site is expected to be completed by 2010. This will be followed by monitoring for about five years to confirm that the
remediation measures are effective.
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Tundra MineTundra Mine
is a former gold mine, located 240 kilometres northeast of Yellowknife.
Operations began in 1964. This is one of three mines that reverted back to
the Crown in 1999 when the mines’ owner at the time, Royal Oak Mines Inc.,
went into receivership.
Why is this a contaminated site?
During the operation of Tundra and nearby Salmita Mines, processed tailings were deposited in Russell Lake (tailings pond).
The water in the tailings pond has elevated levels of aluminium, arsenic, chromium, manganese, copper, iron and lead and is
believed to be the source of contamination downstream. Contamination at the site is associated with the tailings pond, metals leaching from the
waste rock piles and hydrocarbons (fuels and oils) released during operations at the mine.
The Tundra site includes milling and crushing facilities, a tank farm, assay laboratory, powerhouse, head frame and many other support
buildings.
During the operation of nearby Salmita Mine, ore was trucked from the mine along a 10–kilometre road to be processed at the Tundra Mill. Salmita
Mine ceased operations and was remediated by Royal Oak in the 1980s.
What’s going on at the site?
Since 1999, the site has been in care and maintenance mode. This has included dam repairs, geotechnical
inspections, securing buildings and posting signs. Additional work is being done to repair the dams around Russell Lake and more research is
being conducted to develop remediation strategies for the site.
Future Plans
When all the environmental studies are completed, a Remediation Plan will be developed and submitted to the
Mackenzie Valley Land and Water Board for approval. Once the required licences are received, remediation on the site can proceed.
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Rayrock MineRayrock Mine
was an underground uranium mine that operated for two years, from 1957 to
1959. It was operated by Rayrock Mines Ltd., which left the site in 1959.
It is located 145 kilometres northwest of Yellowknife and 74 kilometres
northwest of Rae.
Why is this a contaminated site?
During the operations at
Rayrock Mine, an on-site mill facility processed approximately 70,000
tonnes of ore yielding 207 tonnes of uranium concentrate. The site became
contaminated with radioactive tailings that were deposited on land and
partly flowed into three small lakes. In 1959, two tailings basins
contained 70,903 tonnes of radioactive tailings that had the potential to
leach metals. Construction of the mine also created a source of potential
radioactive contamination through radon gas emissions from the mine
openings (adit, vent shafts).
What’s going on at the site?
In the early 1980s, buildings
were demolished and/or removed from the site. Tailings remediation began
in 1996, with the objective being to contain contaminants at the site and
limit exposure to persons who visit the area. Remediation activities
included sealing mine openings, removing radioactive material from the
dump, disposing of this contaminated material on the tailings, and capping
the tailings piles with a layer of silty clay, followed by
revegetation.
Future plans
Long-term monitoring is ongoing at this site. It
is to be conducted annually for 10 years (2000 to 2009), followed by once
every 10 years for a further 100 years. This may change if results warrant
adjustment, such as some minor care and maintenance work completed in
summer 2004. Monitoring assesses the integrity of sealed mine openings,
water quality and potential risks to humans.
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Discovery MineDiscovery
Mine is a former gold mine, located on the west shore of Giauque Lake,
approximately 80 kilometres northeast of Yellowknife. It was owned by
Discovery Mines Ltd. and was in operation from 1949 to 1969.
Why is this a contaminated site?
At the time of closure,
approximately 1.1 million tonnes of mercury-contaminated tailings were
spread over 32 hectares of land and 3.7 hectares of lake sediment above
the low water level. A tailings beach was created in Giauque Lake. The
majority of the tailings were covered in 1999/2000, although there remains
some residual exposed tailings on site. There also remains old buildings,
mine structures and unsealed mine openings on site that pose contamination
and/or safety risks.
What’s going on at the site?
After extensive assessment,
remediation started in 1998. The work involved the general clean-up of the
site, off-site disposal of some hazardous wastes, and the capping of the
tailings using a low permeability clay cover and waste rock. This work was
completed in 2000.
In the fall of 2001, the silty clay borrow pit, which was used as the
clay source for capping the tailings, became full due to precipitation and
runoff. This borrow pit overflowed into Giauque Lake, creating a sediment
plume. This water is not contaminated from tailings, but contains
suspended clay from the pit itself. To fix this situation, vegetation was
planted on the sides of the pit to stabilize the banks and stop erosion.
The water in the pit is also being treated, and once the clay is settled
out, the clean water is pumped out into the environment.
Future plans
A long-term Environment Monitoring Program (EMP)
was developed and implemented to monitor the effectiveness of the initial
remediation work. This includes monitoring the tailings cap, lake water
quality, sediments, fish and vegetation. A long-term Remediation Plan is
also being developed to address the borrow pit and remaining issues on the
site, such as the buildings and structures.
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Silver Bear Properties
The Silver Bear Properties consist of four former mines; Terra,
Northrim, Smallwood and Norex. They produced silver, copper and bismuth.
Mining began in the area in the 1960s. Terra, Smallwood and Norex mines
were owned by Terra Mining Ltd. and Northrim Mine was owned by Northrim
Mines Ltd. All mining operations ceased by 1985. The sites are located
approximately 300 kilometres northwest of Yellowknife, near the southeast
corner of Great Bear Lake.
Why is this a contaminated site?
There are two tailings ponds
at the Silver Bear Properties, including HoHum Lake at Terra Mine and
Hermandy Lake at Northrim. There is hazardous waste on site, including lab
chemicals, ore concentrates and waste fuels. The containers holding these
materials have degraded and pose a risk to the environment. More than 30
buildings on site have not been maintained and pose safety risks. The
first issue that needs to be addressed on site is sealing the more than 20
openings into the underground mines.
What’s going on at the site?
Studies have been conducted at
the sites since the early 1990s to prepare for remediation. A limited
amount of remediation work has been done so far. This includes placing
leaking barrels of fuel and antifreeze into new containers at Terra Mine
in 1999. In 2001, PCBs and lab chemicals were secured and removed from the
site for disposal.
Studies are continuing to develop a remediation plan and offer insight
into the condition of the water quality, tailings, waste rock and soils.
The contents of 900 barrels at Terra Mine were sampled this year to
prepare for incineration.
Future plans
Once studies have been completed, a Remediation
Plan will be developed and submitted to the Sahtu Land and Water Board for
approval. The Remediation Plan will outline how the tailings ponds will be
treated, how the mine openings will be closed and where waste from the
site will be placed. In the meantime, water quality monitoring will
continue, chemicals will be secured and waste oils will be
incinerated.
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Contact Lake Mine
The Contact Lake Mine is located on Contact Lake, approximately 265 km
east of Déline and 300 km northwest of Yellowknife. It was originally a
silver mine in the 1930s but was mined for uranium from 1949-1950. Mining
operations took place intermittently until 1980. The mine was owned by
Echo Bay/Ulster Peter Ltd.
Why is this a contaminated site?
During the mine's operation,
an estimated 29,100 cubic metres of waste rock and 1,450 cubic metres of
processed tailings were deposited downslope of the mine site towards
Contact Lake. The tailings are not contained. Surface water runs downslope
from the waste rock pile, through the tailings and collects in a settling
(tailings) pond. The tailings and surface mine water have elevated levels
of metals including arsenic and uranium. There is the possibility of
metals leaching from the waste rock piles and tailings to Contact Lake.
There are also old buildings, as well as mine structures and openings,
that pose safety hazards.
What's going on at the site?
In 1993, an environmental
assessment was conducted. Inventory was taken of the buildings, waste
deposits were surveyed, tailings, waste rock and surface water were
sampled and lake bottom sediments were collected.
In September 2002 and June 2003, more water and soil sampling was
conducted to further quantify and qualify the potential impacts of the
mine site drainage on the surrounding environment.
This year, baseline studies have continued, as well as posting warning
signs, installation of groundwater monitoring wells and additional water
quality sampling. The groundwater wells were installed to investigate
groundwater quality and determine if there is a flow path from the
tailings pond to Contact Lake.
Future Plans
Continued water quality monitoring is planned
for Contact Lake. The assessment will be used to create a Remediation Plan
for the site.
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Port Radium Mine Site
Port Radium mine site is located on a peninsula along the eastern shore
of Great Bear Lake in the Northwest Territories, 440 kilometres north of
Yellowknife and 265 kilometres east of the Dene community of Déline. The
site was discovered by Gilbert Labine in 1929 and mined for radium and
silver until 1940. In 1942, the Crown-owned Eldorado Mining and Refining
Company mined for uranium until 1960 before leaving the site. In 1964,
Echo Bay Mines took over operations and mined for silver. Echo Bay Mines
ceased mining operations at Port Radium in 1982 after covering most
tailings and garbage with waste rock, moving all valuable equipment to
nearby mining operations and destroying buildings on-site.
Why is this a contaminated site?
Historical and environmental
studies done to date determine the following concerns: status of closed
mine openings; remaining scrap materials; exposed tailings; elevated gamma
radiation levels at the former plant site and spilled tailings areas;
elevated metals levels in local surface seeps, some vegetation, lake
sediments and water quality; status and environmental issues associated
with exposed waste rock; suitability of on-land tailing covers; status of
uncapped tailings basin; and if any effects are due to the unknown
quantity of tailings deposited into Great Bear Lake.
What's going on at the site?
In 1999, the Canada-Déline
Uranium Table (CDUT) was formed. It is comprised of representatives from
DIAND and Déline residents. DIAND represents Canada on behalf of Health
Canada and Natural Resources Canada. The CDUT created an Action Plan, to
describe, scope and recommend studies and activities that, when completed,
will provide the information necessary to enable the CDUT to make informed
decisions about the long-term management of the Port Radium site and any
ongoing community health requirements relating to the mine site.
Future Plans
In March 2005 the CDUT will complete the Action
Plan final report, which will include results of the CDUT studies and CDUT
recommendations to the Chief and Council and the Minister of Indian
Affairs and Northern Development.
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Axe Point Military Site
Axe Point was an airstrip, staging area and camp along the winter road
to Norman Wells for the American military during World War II. The site
supported the construction of the CANOL Project, an oil pipeline between
Norman Wells and Whitehorse. It is believed that the site was also used
for a couple of years in the early 1940s. Axe Point is 60 kilometres west
of Fort Providence, on the shores of the Mackenzie River.
Why is this a contaminated site?
There is very little
documented historical information about Axe Point. Most of the available
information is from elders in nearby Fort Providence. Remaining on site
are seven collapsed buildings, metal debris, a boiler, several old
vehicles and old batteries. The site is overgrown with willow, alder,
birch and poplar trees. Investigations have found elevated levels of
hydrocarbons and metals in soils and groundwater on site. Geophysical
surveys have identified buried materials on site.
What’s going on at the site?
In 2001, a general site
assessment was done, which included water testing, assessing old
buildings, and gathering information about contaminants on site. In 2003,
more water quality testing was done, including a detailed study of any
impacts on the nearby Mackenzie River. This work was done in cooperation
with the Fort Providence Resource Management Board. Preliminary results
indicate no water is moving from site and there is no impact on the
Mackenzie River.
Future Plans
Further investigations are required to determine
the extent of contamination on site and to determine options for
remediating the site. This information will be used to develop a
Remediation Plan which will be submitted to the Mackenzie Valley Land and
Water Board. Once approvals and licences are obtained remediation can
begin at Axe Point.
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Kittigazuit Military Site
Kittigazuit was used as a long-range navigation site (LORAN) by the
military. This was a significant LORAN site in the northern region, built
in 1947 and operated from 1948 to 1950. The station was code named “Yellow
Beetle”. The site is located near Kittigazuit Bay, located between Inuvik
and Tuktoyaktuk in the Inuvialuit Settlement Region.
Why is this a contaminated site?
After the LORAN project was
shut down, a lot of debris remained at the site, including decaying
buildings and equipment. It was then used as a waste metal depot by DIAND.
Through site assessment, it was determined that there was also DDT and
metal contaminated soils, asbestos waste associated with the buildings,
and hydrocarbon-contaminated soils.
What’s going on at the site?
The scope of remediation of this
site was developed by DIAND and the Inuvialuit Regional
Corporation/Inuvialuit Land Administration. The buildings and contaminated
soils have been removed and remediation should be complete by fall 2004.
March 23, 2006 update: CBC reports that the cleanup of contaminated soil and asbestos which began three years ago is now complete.
Northern Affairs official Emma Pike says the cleanup took longer than expected because there was more contamination than they thought:
"in the initial assessment the one information gap was the degree of contaminated soils in terms of hydrocarbons so when we were cleaning up some of the metal-contaminated soils we actually found some additional hydrocarbonated soils."
The department is now turning its attention to Atkinson Point.
Future Plans
As an Annex ‘R’ site under the Inuvialuit Final
Agreement, once the remediation is complete, the land will be transferred
to the Inuvialuit.
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Atkinson Point Military Site
Atkinson Point, otherwise known as BAR-D was an Intermediate Distant
Early Warning (DEW) Line site located approximately 80 kilometres east of
Tuktoyaktuk by McKinley Bay. This military radar site was constructed in
1957 and operated until 1963. The land reverted to DIAND in 1965. DIAND
made this site available for scientific use by government and university
groups until 1981. During the 1970s, DIAND leased the land to Imperial
Oil.
Why is this a contaminated site?
Most of the visible debris
at Atkinson Point was collected and stockpiled in 1993. However, there are
still several landfills, numerous barrels and several fuel tanks, as well
as buildings contaminated with PCB-amended paint and asbestos. Several
soil samples also showed levels of copper, lead, zinc and PCBs above
guidelines.
What’s going on at the site?
Assessment work is planned for this site after the Kittigazuit Bay military site has been remediated. The
area is still in use by reindeer herders, the oil and gas industry, as well as hunters and trappers.
March 23, 2006 update: CBC reports that the Kittigazuit cleanup is now complete, and a remediation plan for Atkinson Point is developed; that is expected to take about a year.
Future Plans
Preliminary assessment work at this site was completed in 2000. However, several new guidelines or standards are now in
place, and additional assessment work is required. Once this is completed, a Remediation Plan will be developed.
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