Parts of a Uranium Mine - CNSC Online

Parts of a Uranium Mine

Types of mines and mills

Table of contents

Types of mines and mills

Types of mines and mills:
Open Pit

Open pit mines are used when uranium ore is located close to the earth's surface. Open pit mining for uranium is similar to mining for other metals.

An illustration of an open pit mine.

Types of mines and mills

Types of mines and mills:
Underground

Underground uranium mines are entered through a portal that you drive into or through a shaft similar to an elevator.

An illustration of an underground mine.

Types of mines and mills

Types of mines and mills:
Mills

Uranium milling removes uranium from the mined ore (rocks) and transforms the uranium to yellowcake. Yellowcake has the feel of fine sand and can be bright yellow or black in color.

An illustration of a mill.
Parts of a Uranium Mine - 5

Types of mines and mills

Open Pit Mine

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An open pit mine with 8 clickable hotspots.

Open Pit Mine

A mine that is typically developed when the uranium ore is located close to the surface. In most cases, when the uranium ore is located deeper below the surface, underground mining is used.

The open pit mine at the McClean Lake facility.

Open pit mine at the McClean Lake facility

Open Pit Mine

A mine that is typically developed when the uranium ore is located close to the surface. In most cases, when the uranium ore is located deeper below the surface, underground mining is used.

The open pit mine at the McClean Lake facility.

Open pit mine at the McClean Lake facility

Mineralized Rock

Typically, mineralized waste rock is found closer to the uranium ore and contains hazardous or nuclear substances that could negatively affect the public of the environment. It is placed on a liner that collects water that has contacted the rock and sends it to the water treatment plant.

Leachate on a holding pad.

Leachate monitoring on waste and ore rock piles

Ore Storage

The uranium ore is temporarily stored here until it is taken to a mill for processing. It is placed on a liner that collects water that has contacted the ore and sends it to the water treatment plant.

Leachate on a holding pad.

Leachate monitoring on waste and ore rock piles

Mine Headquarters

This is where the staff for the mine change into their personal protective equipment (coveralls, hard hats, radiation monitoring equipment, etc) before going underground.

A mining headquarters interior.

Workers are housed in camps at the mine sites, equipped with kitchen, recreation and social areas.

Water Treatment Plant

Any mine water from the mine site must be treated before it can be discharged into the environment. The water treatment plant removes the impurities from the contaminated water to purify it before it is released to the environment.

The reverse osmosis water treatment plant at Key Lake.

Reverse osmosis water treatment plant at Key Lake.

Treated Effluent Monitoring Pond

Receives water from the water treatment plant where it is temporarily stored until it is tested prior to being released to the environment. If it does not meet the regulatory requirements, it is recycled back through the water treatment plant again and retested.

The McClean Lake mill including the treated effluent monitoring ponds.

Overview of the McClean Lake mill including the treated effluent monitoring ponds.

Treated Effluent Discharge

After being processed treated water from the water treatment plant is discharged back to the environment.

A uranium mine worker collecting a water sample in a lake downstream of a uranium mine or mill

Uranium mine worker collects a water sample in a lake downstream of a uranium mine or mill facility.

Clean Waste Rock

Rock that needs to be removed to access the uranium ore that does not contain hazardous or nuclear substances that could negatively affect the public or the environment.

Large equipment placing clean waste rock in piles.

Large equipment is used to place clean waste rock in piles.

Parts of a Uranium Mine - 6

Types of mines and mills

Underground Mine

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An underground mine with 14 clickable hotspots.

Underground Mine

A mine that is typically developed when the uranium ore is located deeper below the surface. Workers are transported to the underground through a portal or they use a shaft, which is similar to an elevator.

The headframe at the Cigar Lake facility.

The headframe at the Cigar Lake facility

Shaft Headframe 2

The head frame is the building we see on surface. The head frame and shaft are what workers use to enter the mine. Inside, a mine shaft elevator transports workers from the surface to underground.

Two separate head frames at Cigar Lake.

Two separate head frames have been built at Cigar Lake to provide access to the underground workings

Shaft Headframe 1

More than one shaft is needed to provide an additional way for workers to enter and exit the mine. The shafts also provide air, or ventilation, to the work areas underground.

The main McArthur River head frame.

The main McArthur River head frame houses the hoist over the main shaft which deliver miners and equipment as deep as 680 metres below surface

Clean Waste Rock

Rock that needs to be removed to access the uranium ore that does not contain hazardous or nuclear substances that could negatively affect the public or the environment.

An aerial photo of the Cigar Lake facility.

Overview of the Cigar Lake facility, including a clean waste rock pile and a mineralized waste pile

Treated Effluent Monitoring Pond

Receives water from the water treatment plant where it is temporarily stored until it is tested prior to being released to the environment. If it does not meet the regulatory requirements, it is recycled back through the water treatment plant again and retested.

Ponds lined to keep the water collected and treated at the mine site.

Ponds are lined to keep the water collected and treated at the mine site from seeping into the ground

Water Treatment Plant

Any contaminated water from the mine site must be treated before it can be discharged into the environment. The water treatment plant removes the impurities from the contaminated water to purify it before it is released to the environment.

The reverse osmosis water treatment plant at Key Lake.

Reverse osmosis water treatment plant at Key Lake.

Mineralized Waste Rock

Typically, mineralized waste rock is found closer to the uranium ore and contains hazardous or nuclear substances that could negatively affect the public of the environment. It is placed on a liner that collects water that has contacted the rock and sends it to the water treatment plant.

Leachate on a holding pad.

Leachate monitoring on waste and ore rock piles

Ore Storage

The uranium ore is temporarily stored here until it is taken to a mill for processing. It is placed on a liner that collects water that has contacted the ore and sends it to the water treatment plant.

Leachate on a holding pad.

Leachate monitoring on waste and ore rock piles

Mine Headquarters

This is where the staff for the mine change into their personal protective equipment (coveralls, hard hats, radiation monitoring equipment, etc) before going underground.

A uranium mine worker selecting a dosimeter.

McArthur River underground miners are provided individual dosimeters. These dosimeters record exposures to radiation.

Mine Air Exhaust

Fresh air enters the mine from surface, then passes through the mine workings and is exhausted using large fans. These fans exhaust the air away from the mine removing air that may have been in contact with underground equipment or the uranium ore.

The exhaust fans at Cigar Lake mine.

Exhaust fans at Cigar Lake mine

Treated Effluent Discharge

After being processed treated water from the water treatment plant is discharged back to the environment.

A uranium mine worker collecting a water sample downstream of a uranium mine or mill

Uranium mine worker collects a water sample in a lake downstream of a uranium mine or mill facility

Slurry Load Out Building

In high grade uranium mines the uranium ore is ground into slurry (similar to a sand water mixture) and pumped to surface to the slurry load out building. Here the ore is thickened and placed into specially designed containers that are used to transport the ore slurry to a mill for further processing.

A slurry truck.

Truck with containers that hold uranium ore slurry.  This slurry is produced at McArthur River, loaded into these approved containers and shipped

Fresh air shafts

Fresh air shafts also known as ventilation shafts, are vertical passages used in mines to move fresh air underground. Air, or ventilation, is supplied to the underground through these shafts.

The large intake fans at McArthur River mine.

Large intake fans at McArthur River pull air into the underground to provide the work areas with fresh air

Mine shaft

The mine shaft is a vertical tunnel that is used to access the mine. Workers and equipment are brought to the mine through the shaft.

Miners exiting the elevator after their shift at Cigar Lake.

Miners stream out of the elevator after spending their shift more than 400 metres below surface at Cigar Lake

Ore

Rock that contains minerals (in this case uranium) that can be mined.

A miner drilling holes to prepare for the next blast at Rabbit Lake.

Miner drills holes to prepare for the next blast at Rabbit Lake

Parts of a Uranium Mine - 7

Types of mines and mills

Mills

Click on a marker to learn more

A uranium mill with 9 clickable hotspots.

Mill

After mining uranium it is normally processed by grinding the ore materials to a uniform particle size and then treating the ore to extract the uranium by chemical leaching. This milling process produces a dry powder-form material consisting of natural uranium called yellowcake.

A ball mill at Key Lake.

Ball mill at Key Lake. Ore is ground into finer particles

Dump Truck

Dump trucks are used for transporting loose rock material at the mine site.

Large dump trucks transporting material at McClean Lake.

Large dump trucks transport material at McClean Lake

Slurry Truck

Trucks with specially designed containers used for transportation of slurry.

An ore slurry truck arriving for further processing.

McArthur River ore slurry truck arrives at Key Lake for further processing

Mineralized Waste Rock

Typically, mineralized waste rock is found closer to the uranium ore and contains hazardous or nuclear substances that could negatively affect the public of the environment. It is placed on a liner that collects water that has contacted the rock and sends it to the water treatment plant.

Leachate on a holding pad.

Leachate monitoring on waste and ore rock piles

Ore Storage

The uranium ore is temporarily stored here until it is taken to a mill for processing. It is placed on a liner that collects water that has contacted the ore and sends it to the water treatment plant.

Leachate on a holding pad.

Leachate monitoring on waste and ore rock piles

Mill

After mining uranium it is normally processed by grinding the ore materials to a uniform particle size and then treating the ore to extract the uranium by chemical leaching. This milling process produces a dry powder-form material consisting of natural uranium called yellowcake.

The inside of Key Lake uranium mill.

The inside of Key Lake Uranium Mill

Tailings Management Facility

A form of tailings management. Tailing are placed under water in mined out pits. This provides natural long term containment of tailings which can be easily managed.

The in-pit tailings management facility at Rabbit Lake.

In-pit tailings management facility at Rabbit Lake

Treated Effluent Monitoring Pond

Receives water from the water treatment plant where it is temporarily stored until it is tested prior to being released to the environment. If it does not meet the regulatory requirements, it is recycled back through the water treatment plant again and retested.

An aerial of the Key Lake facility.

Overview of Key Lake facility, including the treated effluent monitoring ponds

Water Treatment Plant

Any contaminated water from the mine site must be treated before it can be discharged into the environment. The water treatment plant removes the impurities from the contaminated water to purify it before it is released to the environment.

The reverse osmosis water treatment system.

This reverse osmosis water treatment technology removes heavy metals from the water at Key Lake.

Yellowcake Transport Truck

Standard transport trucks are used to transport the yellowcake packed in steel drums from the mills to the refineries. This transportation of uranium must conform to standards set for transportation of hazardous products.

Barrels filled with yellowcake.

Barrels filled with yellowcake are ready for transport