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Missouri is a State of Mines
Lead Mining

by Susan Ward Aber

The group was taken on a great field trip to see the Doe Run operations in mining, milling, and recycling of lead. The following brief history was compiled using information from our hosts and a 1997 Doe Run Company publication. The group toured the Buick Mine and some statistics are given, followed by some images taken on our adventure in mining! Uses of lead are also provided.

A Brief History

The St. Joseph Lead Company was organized in 1864, with the first company mine at Bonne Terre, southeast Missouri. By the end of 1866, the company had produced and sold 260,126 pounds of lead (today, Doe Run mines produce this amount in 4.5 hours!). By 1869, a diamond drill was acquired and underground mining replaced the open trench mining. The St. Joe company bought more mining options and by 1890 was one of the largest lead producers in the world. They constructed a lead smelter at Herculaneum, Missouri, that has been in continuous operation since 1892 (of course with substantial reconstruction over the years!). In the early 1900s electric locomotives and air-powered drills replaced mule and man power. A mechanical loader on treads went underground in 1922 for extraction and loading, and one year later a 250 mile underground railway system was completed. Subsequently, St. Joe introduced a method for securing overhead rock, the roof bolt, which is still industry standard today.

By the 1950s, the mineral content in the original lead mines was diminishing and favorable deposits were located 50 miles southwest of Bonne Terre, which became known as the New Lead Belt, along the Vibrunum Trend. There are some 35 mines today located along this New Lead Belt and all owned by Doe Run. Although the Doe Run Lead Company was officially formed by St. Joe trustees in 1886 on Doe Run Creek, it was given a new life in 1986 with a joint venture of Homestake and St. Joe Minerals Corporation. In 1994, Doe Run was acquired by a New York firm, the Renco Group, which expanded the company operations to include a lead operation in Peru, a lead recycling facility, and lead fabricated products division.

The Doe Run mines extract polymetallic ores, that is primarily lead, zinc, and copper bearing ore, which involves minerals such as galena, sphalerite, chalcopyrite, bornite, and covellite. The mining is in a room-and-pillar style, which is just as it sounds, the excavation of large square rooms supported by regularly spaced pillars. The rock is blasted, and ore moved by front-end loaders to truck or rail car. The ore rock is then sent through an underground crusher and/or hoisted to the surface through shafts for crushing and milling. It is moved on to the smelter and is refined into 99.99% pure lead cast into precision strips, 5 pound calking lead links, 60 and 100 pound pigs, and 1 ton ingots. The lead is sold in this form or taken to the company's fabricating plants producing custom products for specialized purposes.

Buick Mine Statistics

The Buick Mine was discovered in 1960 and production began in 1969. This mine is nine miles long with a depth of up to 1,240 feet on some five levels. The overall height of the deposit is 60-80 feet in places and 500-700 feet wide. Some 3,400 tons of ore are mined each day and the average grade of the ore: 7.5% lead, 2% zinc, and .14% copper. The ore is relatively free from arsenic, antimony, and bismuth. Without these contaminants, the milling and refining processes are easier and ore "cleaner."

Over 8,500,000 gallons of water is pumped to the surface each day. This amount of water is very low in comparison to other mines, which is in part due to the impermeable Davis Shale layer that is the "roof" of the mine. The aquifer is above this shale layer and therefore the mine is relatively dry.

There are hydraulic drills, 50-ton lo-profile trucks (tractor/trailer), loaders, charging rigs, and scalers, representing almost $2 million in underground inventory and nearly $3 million invested in the support equipment above ground. The trucks are driven some 20,000 miles each month! The ventilation is important to miners and 600,000 cfm of fresh air is moved through the mine, which translates to a monthly energy cost of some $30,000. A concrete operation is also underground, creating new "pillars" so the original ones with high grade ore may be mined.

The mines employ mechanical, chemical, and civil engineers, as well as geologists and miners. Buick has some 90 people working underground per day. This mine has at least a 10 to 20 year life span remaining, which is dependent upon the price of lead and processing costs. Although lights are not abundant underground, some images were successfully taken, which are shown below.

Images in the Buick Mine


The mining geologist orients
the group to the Viburnum
Trend and Doe Run's Buick Mine.

The participants are outfitted with
safety hats, belts, and boots.


We are lowered down a
dark, relatively quiet,
smooth riding lift. This
vertical shaft was over
1200 feet deep.
                                                           

Maintenance on equipment
is all done underground.
                                                           

Almost everything down
in the mine had to be taken
apart to fit the elevator shaft,
and reassembled underground.


Here are some participants
picking up galena.
                                            

We may have been in the dark
but the group listens intently as
the mining process was
clearly detailed!
                                            

The webpage author
and photographer
(hey, who took this one?!).

Uses of Lead

Lead is primarily extracted from the mineral galena, a lead sulfide (PbS) and was among the first minerals discovered and exploited in the New World. Lead mines in Virginia date back to 1621 and mines in what is now Missouri go back to 1690. Today, Missouri produces 90% of the new lead mined in the U.S. and lead consumption has increased by some 50% between 1980 and 1995. Each American now uses some 11 pounds of lead per year.

Lead has been an important resource throughout history, with the earliest known worked lead figurine some 5000 years old! The Roman aquaduct system used lead and the success of the printing press was due to lead fabricated type. Suits of armor from the 16th century were lead. Glass and windows, blown glass, stained glass and leaded designs, have depended upon lead for centuries and still today. Lead was used for ammunition from the Civil War era to present and as a pigment in paint, from 1880s until WWII. It was an additive to gasoline from the 1920s until the 1970s and lead solder sealed canned goods (from 1900s until 1980s). Lead is still used as a solder in the base of lightbulbs and for electronic circuit boards.

Small lead counterweights are added to vehicle wheels for tire balancing and leaded glass screens are used on televisions and computer monitors to protect the user from radiation and serves to enhance the clarity of the picture. Lead has a wide variety of use, from roofing to medicine. Dentists and doctors are aided in diagnosis and treatment with the use of x-rays and radiation therapy (lead-lined treatment rooms and lead "aprons" or shields). Lead also creates a sound wave barrier and is used in the music industry to soundproof recording studios. Lead is resistant to corrosion and can withstand mechanical stress, which makes it useful in the copper refining process. Although it has a wide variety of uses,

the primary use of lead today is for lead acid vehicle batteries

(84% of the U.S. lead mined goes for batteries).

Lead is being recycled at a 90 to 95% rate, one of the highest metal recycling rates. Pollution prevention is a byproduct of recycling and the leader in lead battery recycling is Doe Run! The Buick Recycling plant has received international recognition for a quality facility and produces some 100,000 tons of finished lead annually. We toured this plant also but no pictures were allowed.

Return home or visit the lead mill and stone quarry sites.

Created July 10, 2000; last update, June 9, 2005. © 2000-2005 Susan Ward Aber. All rights reserved.