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.


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.


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.


Types of mines and mills
Open Pit Mine
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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.

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.

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 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 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.

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.

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.

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.

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 is used to place clean waste rock in piles.

Types of mines and mills
Underground Mine
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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
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 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 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.

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 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.

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 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 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.

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.

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.

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.

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.

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 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.

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

Types of mines and mills
Mills
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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.

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 transport material at McClean Lake
Slurry Truck
Trucks with specially designed containers used for transportation of slurry.

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 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 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
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.

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.

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.

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 are ready for transport
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