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On the morning of June 24^th, part of the Eagle Mine heap leach facility failed suddenly and slid downwards. The company later reported that about 4 million tonnes of crushed ore slid that morning, which is about 10 percent of the heap. The rest of the ore in the heap stayed in place and is still there. We do not know how stable the rest of the ore is.

The crushed ore that slid on June 24 contained cyanide solution used to extract gold from the ore. In addition to cyanide, the solution contained other contaminants, such as copper and arsenic. Cyanide is a toxic chemical that can harm fish, other aquatic life, people, and animals at high enough concentrations.

The company also reported that about half of the 4 million tonnes of ore that slid on June 24 moved over the top of the dam that was at the base of the heap and flowed down the Dublin Gulch valley.

To give an idea of how big the ore-slide is, a bulldozer on the slopes in the photo above would only appear as a tiny white dot. The pathway from the top of the failure to where the ore-slide stopped is more than 1.5 kilometers.

The failure damaged some of the waterproof liner under the ore, as well as the dam at the bottom of the heap. The failure also damaged the pumping system that circulated cyanide solution from the bottom of the heap to the gold recovery plant and back to the top of the heap. This means that the cyanide solution in the ore remaining on the heap began to drain out of the heap into the Dublin Gulch valley.

The heap leach facility failure has negatively impacted the environment and unacceptable risks still exist at the site. Urgent action is needed to protect fish, other aquatic life, animals, and people

FNNND has been actively engaged and advocating for robust emergency response since day one. FNNND immediately took water samples and formed a technical team of staff and consultants. FNNND played a strong leadership role in developing monitoring programs and emergency response plans with the Government of Yukon. FNNND has been regularly taking water samples and monitoring downstream of the failure since June 25. See the for information about FNNND’s involvement and advocacy.

August 12, 2024, Updated August 23 to reflect YG’s unacceptable ToR for the independent review and to emphasize the importance of a public inquiry.

The cause of the failure is not yet known. FNNND is calling for a full and independent inquiry, under the Public Inquiries Act, to examine ALL causes of the failure, including technical, legislative and regulatory oversight failures that caused this catastrophe.

In general, from a technical and engineering perspective, the cause of a heap leach facility failure can be in the design, construction, operation, or maintenance of the facility, or some combination of these. Only an independent investigation by experts can reliably tell us the technical causes of the heap leach facility failure on June 24, 2024.

It is, however, not enough to know only the technical causes. A public inquiry is essential to get to the root of ALL possible causes of the failure. This includes a close look at how mines in the Yukon are approved, regulated, inspected, and enforced. The Government of Yukon has not yet agreed to a public inquiry.

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The heap leach facility at the Eagle Mine is a huge heap of crushed ore on a lined pad. Ore is rock that has enough gold to be economically valuable. Victoria Gold said that on the day of the failure, there were about 39 million tonnes of ore on the heap.  This image shows what the mine looked like before the failure.

During operations, Victoria Gold dripped cyanide solution (cyanide dissolved in water) to leach gold from the ore. Cyanide is a chemical favoured by the mining industry to extract gold. Cyanide is a toxic chemical, although some forms of cyanide are more harmful than others.

During operations, the cyanide solution picked up gold as it moved down through the ore and collected on the lined pad under the ore. The gold-rich cyanide solution flowed down the liner, and eventually pooled at the bottom of a dam at the base of the heap. Victoria Gold pumped the gold-rich cyanide solution to the gold recovery plant. There, the gold was turned into gold bars. Victoria Gold continuously reused the cyanide solution by pumping it back to the top of the heap. This method of removing gold from ore is called heap leaching.

Cyanide at high-enough levels is very toxic to people and animals, and especially to fish and other aquatic life. Other contaminants in the solution, such as metals, can build up in the ecosystem and cause damage over the long-term.

When working as intended, the heap leach facility is designed to keep the cyanide solution contained and none should escape into the environment.

A heap leach facility must be designed and built by experienced professionals so that it is stable and safe for workers and the environment. It must be operated responsibly to make sure it does not leak or fail.

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The Traditional Territory of the First Nation of Na-Cho Nyäk Dun is vast, with sacredness and important cultural touchstones found wherever you may walk. When a part of our lands and waters is harmed, we all feel that pain. To better understand the seriousness of our lands and waters being harmed by the failure at Eagle Gold, we wish to share a small part of our connection to the areas that have been damaged.

Et’o Nyäk Tagé (McQuesten River)
Et’o Nyäk Tagé, or the McQuesten River, roughly translates from Northern Tutchone as “river with lots of nests.” Here, there is an abundance of wetlands up the valley, and it provides important spring nesting and staging habitat for many birds. The Et’o Nyäk Tagé is an incredibly vibrant watershed that hosts a plethora of habitats and ranges which have supported First Nation connection with the land for countless generations. The headwaters around Et’o Nyäk Män (McQuesten Lake) originate from a massive wetland complex that bridges the Tsé Tagé and Et’o Nyäk Tagé Watersheds. Traditional, seasonal travel routes involved travel up the Et’o Nyäk Tagé valley, into the Tsé Tagé Watershed which connects back with the Upper Stewart River Watershed—a route that would often be accomplished in part by moose skin boat.

The spring grayling fishery on Et’o Nyäk Tagé has been a core community fishery that has sustained our People through the generations and occurs at the mouth of Haggart Creek. The grayling which support this culturally vital fishery spend their summers in Haggart Creek, and particularly in the Lynx Creek tributary (adjacent to Dublin Gulch).
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Et’o Nyäk Tagé is also host to Chinook and Chum salmon who spawn on the river proper and in the tributaries. Et’o Nyäk Tagé may be considered the most important salmon tributary of the whole Stewart River. Juvenile and adult salmon have been documented up Haggart Creek and tributaries. The watershed has already seen great impacts from mining development over the past century including toxicity due to previous silver mining malpractice. In the mid-1950s, local residents noted a huge kill of fish down the river, the result of toxins from Elsa mining tailings. Ancillary activities such as logging, road construction, market hunting and fishing to feed miners and even the intentional poisoning of Hanson Lakes to support stock of rainbow trout for sport fishing have all had a cumulative toll on the area. An extensive study of water quality in the South McQuesten River in 2023 showed evidence of continued negative cumulative effects in the watershed.

The Dublin Gulch‍
The Dublin Gulch is within the Haggart Creek drainage area of the watershed, and is a particularly important place close to Mayo, Elsa, and Keno, where traditional subsistence harvest, connection with land, and cultural continuity have continued to this day. Before Victoria Gold even began operation, cumulative effects within the area were already noted to have impacted use of the land by First Nations and locals. Over a century of placer mining, exploration, and adjacent mining activity have affected the area. The Potato Hills region (the hills stretching East from the Eagle Gold Mine) used to be a vital hunting and gathering place, including for the gathering of traditional medicines. These hills are noted for providing some of the most pivotal moose late wintering area in the entire Mayo Moose Management Unit which has experienced significant decline in moose population.

Et’o Nyäk Tagé is also host to Chinook and Chum salmon who spawn on the river proper and in the tributaries. Et’o Nyäk Tagé may be considered the most important salmon tributary of the whole Stewart River. Juvenile and adult salmon have been documented up Haggart Creek and tributaries. The watershed has already seen great impacts from mining development over the past century including toxicity due to previous silver mining malpractice. In the mid-1950s, local residents noted a huge kill of fish down the river, the result of toxins from Elsa mining tailings. Ancillary activities such as logging, road construction, market hunting and fishing to feed miners and even the intentional poisoning of Hanson Lakes to support stock of rainbow trout for sport fishing have all had a cumulative toll on the area. An extensive study of water quality in the South McQuesten River in 2023 showed evidence of continued negative cumulative effects in the watershed.

‍Ongoing Risk of a Disastrous Release of Cyanide Solution

As a result of the June 24 heap leach facility failure, there is an unacceptable risk that toxic wastewater containing cyanide and other contaminants could be released into Haggart Creek. Haggart Creek runs from the site into the McQuesten River, to the Stewart River, and into the Yukon River. Cyanide is very toxic  to people and the environment at high enough levels.  It is especially deadly to fish and other aquatic life.

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Groundwater Contamination

A second major concern at the site is groundwater contamination. As a result of the failure, cyanide solution can flow over areas of the site that are not designed to contain this high-risk wastewater. For example, a significant  volume of cyanide solution is in direct contact with the ground in Dublin Gulch. Dublin Gulch is not lined and the ground contains coarse geologic material, meaning there is little to prevent or slow the infiltration of cyanide solution  into the ground and reaching groundwater. Cyanide solution may also enter groundwater where the heap leach facility liner was damaged.

The extent of groundwater contamination, including severity and location is uncertain. Immediate action is needed to prevent more groundwater contamination and to stop groundwater that is already contaminated from entering creeks and rivers.

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Surface Water Contamination

At this time, we are unable to determine how much cyanide solution may have been released directly into surface waters as a result of the heap leach facility failure. The ore that slid on June 24 blocked surface flow of cyanide solution from flowing freely into Haggart Creek. Also, Victoria Gold built dams to block cyanide solution from entering the creek. However, the failure resulted in an unstable situation that has resulted in some of the cyanide entering surface water.  

Most notably, fish were killed in Haggart Creek in early August following the discharge of toxic water from Victoria Gold’s water treatment plant. Water analyses later revealed high levels of cyanide in the treatment plant discharge. This was an unacceptable and avoidable incident.  The fishkill happened while Victoria Gold was still in charge of managing the site. The company reported that it collected 68 dead fish on August 2.

In addition to the fishkill, monitoring results reveal that cyanide has been at unsafe levels for fish on several occasions.  [insert drone photo of Haggart Creek with a view of the mine, with caption]

Immediate and robust action is necessary to prevent further harm to surface water from the heap leach facility failure. To better understand the extent of contamination, FNNND is monitoring Haggart Creek and the McQuesten River. FNNND will regularly post the results of such monitoring.

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The First Nation of Na-Cho Nyäk Dun, in collaboration with Yukon Government Department of Environment, are running a wildlife monitoring program in response to the June 24th failure at Eagle Mine. The program will look at monitoring frogs, birds, and mammals, with special attention paid to moose and aquatic mammals like muskrats, beavers, and otters.

The specific samples the program is looking for will come from caribou and moose harvested anywhere in the McQuesten River watershed. Samples requested from each animal harvested are 1 kidney (with surrounding fat), 1 chunk of liver (about the size of a 500g butter cube), 1 chunk of hindquarter meat (500g), and the front of the lower jaw (with incisor teeth).

FNNND and YG are asking for participation from the public in this program. Hunters can pick up a testing kit from:

First Nation of Na-Cho Nyäk Dun Lands office in Mayo Land Guardians Yukon Government's Department of Environment office in Mayo & Whitehorse. Participants will receive a gift as gratitude for their participation. For more information, please contact Mark O'Donoghue at markodonoghue@nndfn.com

The First Nation of Na-Cho Nyäk Dun has developed an emergency plan to protect fish in case contamination in Haggart Creek rises to levels that would seriously harm or kill fish. This emergency plan includes placement of weirs to keep salmon and grayling from moving into Haggart Creek. It also includes fish salvage operations to move fish out of Haggart Creek to avoid contaminated water, if it becomes necessary.

In early August, the federal Department of Fisheries and Oceans (DFO) issued a Corrective Measures Order that required Victoria Gold, who was still in charge of the site at the time, to place weirs at 7 sites along the Creek to limit fish movement. DFO issued the order as a result of Victoria Gold's water release from their treatment plant that resulted in the deaths of at least 68 fish. DFO also required Victoria Gold to move fish out of a portion of Haggart Creek, immediately below the mine where cyanide had been detected.

DFO did not consult with FNNND before issuing the initial order. As a result, the DFO Order interfered with the fish monitoring program that FNNND had been conducting with Yukon’s Department of Environment. Over 1,300 fish were moved from Haggart Creek to the South McQuesten River and there was no recording of whether or not these fish were tagged from the FNNND-YG program. As a result, it will be difficult to distinguish effects of the mine heap leach failure from those of the fish salvage. DFO has since been communicating better regarding management of fish weirs on Haggart Creek and consulting FNNND before issuing subsequent Corrective Measures Orders.

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 Introduction

The First Nation of Na-Cho Nyäk Dun (FNNND) has taken a lead role in planning and initiating environmental monitoring. FNNND began monitoring on the day of the failure and has been monitoring regularly ever since. FNNND has collaborated with Yukon Government's Department of Environment’s Water Resources and Fish & Wildlife branches to develop the monitoring plans that are in action now.

This collaboration resulted in three programs for ongoing monitoring effects in Haggart Creek, downstream of the heap leach facility failure. These programs monitor water quality, fish and fish habitat, and living organisms other than fish. Though the monitoring programs are separated into three groups, they are all linked, as nothing in nature exists in a vacuum. If part of the ecosystem is unhealthy it affects all other parts. NND created these groups to reflect the holistic goals of monitoring the entire aquatic ecosystem.

To date, most  of the water sampling has been of surface waters. There is a significant need to conduct more groundwater sampling. However, it is not yet known where the groundwater is moving, how fast it is moving, where it will come to the surface, or at what rate it will be released into surface waters. Therefore, there remain a lot of questions about the effects this contamination will have in the environment. Monitoring is essential to help us track contamination from cyanide, heavy metals and other pollutants, now and in the future.

These are short-term triage plans to keep close track of water quality and fish in the Haggart Creek watershed. NND chose to focus on fish because they are especially sensitive to cyanide. Effects on fish are therefore an early warning that cyanide may be entering the watershed.

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 More Detail About NND’s Monitoring Programs

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Fish and Fish Habitat

FNNND is working collaboratively with YG to monitor fish and fish habitat in the Haggart watershed. Canada’s Department of Fisheries and Oceans has recently become involved with salmon-related monitoring. 

What is the purpose of the fish monitoring program?

Cyanide in fairly low concentrations (above 5 parts per billion) can negatively affect fish health (behaviour, movements, growth, reproduction) and at higher concentration will kill fish.  Haggart Creek is a habitat for several fish species, including a well-known population of grayling. Importantly, it is also used by Chinook salmon for rearing and spawning. Fish monitoring has three main goals. First, because of their sensitivity to cyanide, FNNND can look in Haggart Creek for dead or unhealthy fish to provide an early warning about cyanide released into the environment. Second, by surveying fish all through the Haggart Creek watershed, information may be provided on what type of fish are present, how many there are, habitat quality, and where fish are distributed. This will support stock management and planning for emergency measures, such as a fish salvage. Third, the fish monitoring provides data on the fish populations in the creek that are unimpacted from cyanide contamination, allowing the team to  monitor short- and long-term effects of contamination. It is expected that this program will run for decades.

How are fish being monitored?

The initial fish survey was conducted in July 2024. FNNND and YG crews captured fish at 47 sites, using a combination of methods such as electrofishing, minnow traps, and nets. About half of the sites were located on Haggart Creek, downstream of the mine site. These sites may have been impacted by the heap leach facility failure. The other half of the sites were at locations upstream of the mine site and in streams and creeks that feed into Haggart Creek. These fish surveys will allow NND to compare fish population health in areas where contamination is most likely, with fish from areas without contamination. Many of the same sites were surveyed in 2010 by Victoria Golds’ consultants for the original mine application.

During the surveys, about 200 grayling were tagged in order to track their movements. This will provide data on where fish spend their time, what habitat is preferred, overall survival, and the number of fish that grow from juvenile to adult stage.

Tissue samples were taken from 68 grayling and 37 sculpin to analyze for contaminants present in their bodies, such as heavy metals. Cyanide degrades in fish tissue once the fish has died, and can no longer be measured. This is good news for the safety of eating fish, but it makes it hard to know if cyanide is the cause of fish deaths.

FNNND will compare the fish tissue results with fish tissue samples collected in the future. The goal is to see if there is a measurable increase in contaminants in fish in the Haggart Creek watershed. This will help understand health concerns related to eating fish. It will also help to make decisions about fisheries management.

FNNND is prepared to  expand monitoring if there is any sign of contamination in surface waters moving downstream from Haggart Creek.

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How long will the fish monitoring program last?

The short-term fish monitoring program is meant to be adaptable. It is likely to be modified as the situation evolves. The long-term program will likely last decades. Cyanide does not accumulate in fish tissue but there is a desire to monitor levels of other contaminants that do accumulate such as heavy metals..

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 Who else is monitoring fish?

The Department of Fisheries and Oceans Canada (DFO) has acknowledged that the heap leach facility failure could impact Canada’s already declining Chinook stock. The failure could impact the importance of the South McQuesten River as a key spawning habitat for Chinook. In response to the heap leach facility failure, DFO is creating a Salmon Monitoring Plan that will include monitoring for spawning adults and which species are present. DFO’s monitoring will help understand where juvenile Chinook reside. DFO will monitor in the McQuesten River from the mouth of the Stewart to where Haggart creek runs into the South McQuesten River.

DFO conducted salmon spawning surveys in late July and early August to monitor potential effects further downstream in the South McQuesten River. DFO is also making plans to assess fish winter habitat in the Haggart Creek watershed that will help FNNND with planning the need for further fish salvages.

Tr’ondek Hwech’in has also conducted some downriver sampling of water quality in the McQuesten River. 

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What is aquatic effects monitoring?

The Aquatic Effects Monitoring Program is designed to determine the effects of the heap leach facility failure on organisms other than fish that live in the creeks and rivers downstream of the mine. Under this program, NND and YG will monitor bugs at the bottom of the stream (benthic invertebrates), and algae (periphyton). There will also be samples taken of stream sediment (rocks and mud that cover the bottom of streams). The aquatic effects monitoring programs are designed to be long term programs with sampling conducted at least once every year, to create a database that can demonstrate how things are changing and whether there are long-term impacts on life in the watershed.

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 Why monitor bugs in the water?

Bugs that live at the bottom of water bodies (also called benthic invertebrates) are an important food source for fish and contribute to healthy habitat by recycling stream debris. These bugs can tell us about the health of streams, because certain bugs seem to tolerate ‘polluted’ water and others do not. This community structure can be measured (the number and type of bugs) when a sample of the bugs are taken. Over time the community structure change may also be observed in response to an impact. This is why it is critical to have quality reference sites that are unimpacted (reference data), or a good knowledge of what the community was like before (baseline data).

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 How are bugs in the water being monitored?

Bottom-dwelling bugs will be analyzed to measure contaminant levels. Samples will be taken from near the heap leach facility failure, and further away, down into the South McQuesten River. This will help FNNND understand the longer-term effects of the heap leach facility failure on the aquatic ecosystem. This monitoring began in August 2024 and will continue for likely decades. Why monitor algae?

Algae is a primary producer in the food chain, meaning it gets its energy from sunlight. Algae is food for bottom-dwelling bugs. All life in the streams are connected. By monitoring algae, FNNND can better understand if there are changes in the environment from the heap leach facility failure. FNNND is developing the algae sampling program now.

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 How and why is NND monitoring sediments?

NND will be taking samples of sediment and analyzing them for cyanide and metals. The sediment monitoring program is being planned by FNNND and the Yukon Government , with sampling beginning in  August 2024. The purpose of this program is to monitor any adverse impacts to sediment quality in Haggart Creek over time, as a result of the heap leach facility failure.

It is possible that coarse (gravel-sized) and fine (extremely small clay and silt) material from the crushed ore heap eroded  the creek bed during the ore-slide. Creek bed materials and other materials disturbed during the failure may have entered Haggart Creek and could be transported downstream. Depending on the stream size and flow, sediment can deposit in riverbeds far downstream of the mine.

Fine sediments from the failure could fill in tiny spaces in the materials in the stream bottom, thereby reducing habitat for bottom-dwelling bugs. Sediment can also cover and suffocate fish eggs. Stream sediment can act like a sink for contaminants like heavy metals that are transported from upstream. Bugs that live within the sediment would have a higher exposure to these contaminants, which could affect community structure and abundance. Fish eggs that are in the sediment may also be exposed to contaminants.    

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FNNND began taking water samples on June 25^th, 2024, one day after the heap leach facility failure. FNNND environmental monitors have been regularly taking samples since then to understand whether cyanide and other contaminants are entering creeks and rivers, and if so, in what amounts.

Water quality monitoring involves taking samples of water and sending them to a lab for chemical analysis of cyanide and other contaminants. Water quality monitoring helps to understand the risks to fish, other aquatic life, plants, animals, and people. The monitoring results can also determine if contaminant levels downstream of the mine are going up or down. Once emergency response and remediation is being conducted, the monitoring data will help inform if those actions are working. The water quality analyses also inform NND’s recommendations for actions at the Eagle Gold site.

FNNND took a leadership role in developing water quality monitoring plans. FNNND takes its own samples, so that results can be verified alongside other parties providing  FNNND with stronger confidence in the results.  

FNNND collaborated with YG to develop the monitoring program, and ongoing collaboration is intended as the program expands . FNNND and YG share results between governments to create a more robust and informative set of monitoring data.

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Where does FNNND sample?

FNNND takes samples in Haggart Creek between the Eagle Gold site and the South McQuesten River. FNNND also samples the South McQuesten River upstream and downstream of Haggart Creek. In total, FNNND samples from 10 sites. YG also takes samples and measures flow rates on Haggart Creek at the same sites. 

FNNND does not yet sample on the mine site near the heap leach facility. This is because the team is not yet satisfied that it is safe for FNNND environmental monitors to go that close to the heap leach facility.

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How often does FNNND sample?

FNNND samples Haggart Creek daily at the mine site and up to 5 km downstream of the site. FNNND samples locations further downstream on Haggart Creek and on the South McQuesten River every other day.

How long does it take to analyse the samples?

The samples that are sent to Vancouver for analysis take up to one week. FNNND has purchased equipment that allows same-day testing methods for cyanide. Metals and more detailed cyanide analyses happen at the lab in Vancouver. YG also has same-day testing equipment and uses it at high-risk locations on the mine site. YG shares these results with FNNND.

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How long will FNNND monitor water quality?

FNNND expects to continue monitoring for many years.

What do the monitoring results tell us about the safety of water downstream of the mine?

FNNND is working on tools to analyze the results and report these to FNNND citizens. FNNND will analyse the data to understand risks and to know if concentrations of cyanide and heavy metals are going up or down.

In the meantime, the Government of Yukon is publishing their data on their website:  https://yukon.ca/en/victoria-gold-updates/environmental-monitoring.

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Impacts of Winter and What to Expect in Spring

Prepared by Ewaschuk Consulting, with input from Bill Slater and Cord Hamilton.

Information current as of December 12, 2024.

What work needs to be done over the winter?

• Months after the initial heap leach failure, effective water treatment is still not available at the site. Effective water treatment is the only way to safely discharge all the excess cyanide-contaminated water from the site. It is critical to get effective, reliable water treatment in place in the winter months to avoid uncontrolled discharges of cyanide and other contaminants.
• Ramping up groundwater collection will also be critical to protecting Haggart Creek as its flow drops over winter. Successful groundwater collection has been minimal so far. Contaminated groundwater has spread throughout the Dublin Gulch Valley from the conveyor road all the way down to Haggart Creek.
• Efforts to collect cyanide-contaminated water that is spilling from the Heap Leach Facility (“HLF”) must continue throughout the winter and until the sources of this toxic water have been contained and the valley cleaned up.
• While the volume of water that must be collected each day is expected to decrease over the winter as the site freezes, about 2,000 m³ of new contaminated water will have to be collected every day. Unfortunately, the amount of contaminated water that needs to be stored is likely to increase as the Receiver ramps up groundwater collection. (The Receiver is PricewaterhouseCoopers, the company that took control of the site from Victoria Gold.) On-site storage capacity for contaminated water will continue to be a challenge throughout the winter.
• Continually collecting the cyanide-contaminated water is not a complete solution because there is a limit to how much storage space can be built. Also, there must be storage space available to contain the large spring runoff that will also be contaminated. For these reasons, FNNND continues to press for more storage ponds.
• Further, because of the dire need to treat and release water and because effective water treatment is not yet available, the Receiver has applied to the Yukon Water Board (“YWB”) to relax the legal limits for cyanide, ammonia, copper, iron, and total suspended solids in Victoria Gold’s water licence on an emergency basis. The Receiver says that this is necessary so they can release partially treated water from the site and thereby make space for the additional contaminated water that continues to accumulate. They have asked to release this water beginning as soon as possible until the end of March. After that, they say they can meet the original licence limits. As of writing, the Receiver’s emergency application is still being considered by the YWB. 
• All of the above efforts are meant to manage the fallout from the June 2024 collapse of the HLF. However, they do not address the stabilization and restoration of that critical facility. Until the heap is stabilized and, most importantly, water control is re-established, the emergency will not be under control. The heap of crushed ore is ultimately the main source of cyanide that is being lost into Dublin Gulch and so it must be repaired to stop this from continuing.
• Over the winter, the Receiver’s engineering consultants will analyze the stability of the heap and make plans to stabilize it and to stop the overflow of cyanide-contaminated water. We will advocate for efforts to re-establish control of the water flowing off the heap. Construction of the more significant earthworks necessary to stabilize and fully repair the heap (if that is possible) will likely not begin until after the freshet in spring 2025.  
• Water quality monitoring will continue throughout the winter.
• During the summer and fall, baseline data on fish and other aquatic life was gathered to help us understand the effects of the disaster. Monitoring during the winter will be limited to locating the most likely habitats for overwintering fish.
• Over the winter, FNNND will continue to strongly advocate for a robust audit or inquiry into the disaster that considers the Government of Yukon’s role as regulator of the mining industry.

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How does winter affect emergency response efforts?

• During winter, pipes, equipment, sumps, and ponds can freeze. This makes the management of the Eagle Gold Mine site very difficult in frigid temperatures. Measures to prevent freezing can help but are not fail-proof, and complications due to freezing are expected.
• Some small spills of cyanide-contaminated water from frozen pipelines and pumps have already happened and are likely to occur again in the extreme cold.
• During winter, construction is difficult because materials are frozen, daylight hours are short, and extreme cold can make it hard to get much done. Large construction projects will generally need to wait until the summer to resume.
• The reduced winter flows in creeks and rivers means that there is less dilution of any discharges of contaminated water during the winter. This means that if there are winter discharges of contaminated water, concentrations of cyanide and other contaminants will be higher in the creeks and rivers than they would be in the wetter, summer months.
• Migratory fish like arctic grayling mostly leave creeks and rivers near the mine at this time of year. But fish species that live year-round in the area, such as sculpins, will remain and will be exposed to any cyanide and other contaminants that are released into Haggart Creek.
• Ice conditions limit our ability to monitor fish and other aquatic life during the winter, especially during ice formation. At that time, unstable ice makes access to the creek dangerous. During the ice-free seasons, effects of toxins on fish are readily observable, whereas in the winter, effects are largely hidden under ice.

What can we expect in spring freshet 2025?

• The spring freshet is the highwater event that occurs from the seasonal snow melt.
• This will pose a serious risk to water management, unless enough contaminated water storage and treatment capacity is created over the winter.
• If not properly controlled, more contaminated water will soak into the ground as it thaws and add to the contamination already in groundwater.
• Spring freshet can increase the risks of another HLF failure. The large amount of water that will soak into the heaped ore and flow downwards can reduce the stability of the heap.
• Shortly after peak creek flows in May, many thousands of grayling will try to move back up Haggart Creek for the summer after spawning in the South McQuesten River. If Haggart Creek is toxic to fish due to contaminated water from the mine, there are limited options for protecting them. Weirs are difficult to install and maintain when water flows are high and the impacts of depriving these fish of their summer habitat would have negative and possibly long-lasting effects on fish population health.
• FNNND will continue to advocate for measures to prevent harm to the Haggart Creek grayling population.
• FNNND will continue to update our Citizens regarding the safety of fish and wildlife populations in the area.

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