In
this article we will take you to some gigantic man-made holes: open pit
mines. We’ll show you the biggest, deepest and deadliest mines in the
world. All of them are located in the United States and can be visited.
The great thing about these mines is that visiting them is very cheap
in comparison to what they are offering. You’ll get some spectacular
views for sure and in the mines that are still active you can see rock
explosions and gigantic dump trucks. Some mines also have a visitor
center or a museum.
Open pit Mine (Photo by
wikipedia)
The biggest mine
The worlds biggest open pit mine can be found near Hibbing,
Minnesota. At its maximum, the area covered by the Hull Rust open pit
mine is five miles (8km) long, 2 miles (3,2km) wide and 535 feet (180m)
deep. It looks like a man-made Grand Canyon of over 2,000 acres
(8,1km²). The first iron ore extractions were made here in 1895.
Beginning as a small underground mine, the land eventually became one
vast open pit as other mines began to develop and emerge. The center of
the actual pit is located where the original town of Hibbing once stood.
As the mine grew bigger, the town had to be moved. The move started in
1919 and took two years to complete. 185 houses and 20 businesses were
moved a couple of miles to the south. Some of the larger buildings even
had to be cut in half before they could be moved. A few remnants of the
original town are left near a lookout point at the edge of the mine.
Hull Rust mine (Photo by
joukork)
Since the Hull Rust mining operations started 1895, over 530 million
tons of waste material and nearly 700 million tons of iron ore have been
extracted from the pit. It has been calculated that all the material
removed - approximately 1.2 billion gross tons - is equivalent to
digging a tunnel through the core of the earth and out the other side.
The mine is still operated today by the Hibbing Taconite Company, and
taconite pellets are extracted at the rate of 8.2 million tons annually
(not counting waste overburden).
Mining excavator (Photo by
not1word)
There is an observation building from where you can overlook the
mining activities. A slide presentation explains the history of the mine
and early miner's activities. A mine shovel bucket, a mining truck and a
walking trail make the trip complete. The mine can be visited from
mid-May through September.
The deepest mine
Bingham Canyon Mine, located near Salt Lake City, is the world's
deepest man-made open pit excavation. The mine is 2.75 miles (4,5km)
across and 0.75 mile (1,2km) deep. Since mining operations started in
1906, Bingham Canyon Mine has been the granddaddy of all copper mines.
When you're talking about the actual size of the mine, Bingham Canyon is
simply the largest copper mine in the USA. If the mine was a stadium,
it could seat nine million people.
Aerial view Bingham Canyon Mine(Photo by
Ren Shore)
Bingham Canyon is primarily a copper mine, but it has also yielded a
wide range of byproduct metals. These include 620 tons of gold, 5,000
tons of silver, 276 tons of molybdenum and large amounts of platinum and
palladium. The Kennecott mining company extracts daily approximately
450,000 tons of rock out of the mine. With these production statistics,
it's no wonder that the Bingham Canyon Mine has been nicknamed "the
Richest Hole on Earth." The value of metals produced yearly at Bingham
Canyon is US$1.8 billion dollars.
Bingham Canyon Mine (Photo by
Timjarrett)
Kennecott has built a visitor’s center dedicated to educating the
public about mining practices, sustainable development and the
importance of mining in modern life. Visitors get breathtaking views and
the opportunity to see giant electric shovels fill 320-ton capacity
haul trucks that deliver ore to the in-pit crusher. A video, historic
photographs and 3D models are also available inside the visitor's
center.
Dump truck getting loaded (Photo by
Caterpillar)
The mine is operating 24 hours per day, 365 days a year. Visitors may
come from April 1 through October 31, seven days a week. Entrance fees
are $5 for passenger vehicles, $25 for mini tour buses and $50 for tour
buses. All entrance fees are donated to charity.
The deadliest mine
Just outside Butte, Montana lies Berkeley Pit: a pit filled with
greenish poison a mile and a half wide and over a third of a mile deep.
It was once a thriving copper mine where millions of tons of copper ore,
silver, gold, and other metals were extracted from the soil.
When underground mining became too costly in the 1950’s, Berkeley Pit
became an open pit mine. As the mine grew bigger and deeper,
groundwater began to seep into the pit, and pumps had to be installed to
keep it from slowly flooding.
Berkeley Pit (Photo by
toddtrigsted)
Thirty years later, the mine was so exhausted that it was no longer
profitable. The pit was abandoned and the water pumps were shut down.
Without the pumps, rain and groundwater gradually began to rise in the
pit, leaching out the metals and minerals in the surrounding rock. The
water became as acidic as a lemon, creating a toxic mixture of heavy
metal poisons such as arsenic, lead, and zinc. No fish live there, and
no plants line the shores. There aren’t even any insects around, only
some rare kinds of microorganisms survive in the toxic water. The
Berkeley Pit had become one of the deadliest places on earth. The
iron-rich water near the surface is reddish, yielding to a vibrant
lime-green hue not far below the surface, where copper concentrations
are higher. If you were to drink large amounts of this water it would
kill you by corroding your body from inside.
Water in Berkeley Pit (Photo by
kolopres)
In 1995, a flock of snow geese stopped for a rest at the pond, and
342 of them died there. Authorities use gunshots and loudspeakers to
scare away migrating waterfowl, but there have been a few smaller
die-offs nonetheless. Sometimes a sinister mist creeps out of the Pit
and into the streets of Butte. Citizens are scared about this
potentially poisonous fog. The water level is still rising, and if
unchecked it will spill over into the area’s groundwater in twenty
years. That danger made the area one of the EPA’s largest Superfund
sites. Currently, the EPA’s plan is to focus on containment.
Berkeley Pit fog (Photo by
toddtrigsted)
The water in the pit is so saturated with metals that Montana
Resources Inc. is able to extract copper directly from the water. 13
million gallons (68 million liters) per day, is pumped from the deeper,
copper-rich part of the lake to nearby scrap iron holding ponds, causing
the copper and iron to swap places. The resulting copper sludge yields
up to 180 tons of copper a month. The now iron-rich water is pumped back
into the Berkeley Pit, creating the waterfall seen on the northeastern
rim. In the meantime, the Pit has become a tourist attraction.
There’s a small museum and gift shop located well above the water level.
The Berkeley Pit Viewing Stand, open from March until November has an
admission fee of $2.
