Date: December 4, 2009 

Subject: Site Visit – Doe Run Company 

Nonferrous Metals Sector Project 

 EPA Contract No. EP-D-06-118; EPA Work Assignment No. 3-21 

 RTI Project No. 0210426.003.021 

From: Michael N. Laney 

 

To: Chuck French 

 EPA/SPPD/OAQPS 

U.S. Environmental Protection Agency 

 Research Triangle Park, NC 27711 

1. Purpose 

The purpose of the site visit was to gather information on The Doe Run Company’s primary lead 

smelting facility and operation in Herculaneum as well as their secondary lead recycling facility 

and operation. In addition, information on their mining and milling operations and a new 

hydromettalurgical process was to be gathered. 

2. Pre-Site Visit Meeting 

Prior to the site visit to the Doe Run Co. mining, milling, primary and secondary lead facilities, a 

pre-site visit meeting was held in St. Louis. The following individuals attended this meeting and 

were present at each of the site visit locations: 

Gwen Yoshimura, EPA Region 7 (Host agency) 

Mike Jay, EPA Region 7 

Andy Chang, EPA Region 5 

Gilberto Alvarez, EPA Region 5 

Joe Winklemann, Missouri Department of Natural Resources 

Chuck French, U.S. EPA 

Sharon Nizich, U.S. EPA 

Rhonda Right, U.S. EPA 

Tom Rossendahl, U.S. EPA 

Mike Laney, RTI International 

A representative of the host agency presented background information on past and current state 

implementation plan (SIP) activities related to the Doe Run Company’s primary lead smelter in 

Herculaneum. A brief overview of the planned hydrometallurgical primary lead process and 

Buick Recycling Center was given. 
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3. Doe Run Company, Herculaneum Smelting Division, Herculaneum, MO, 

October 19, 2009 

At the Doe Run Herculaneum facility, representatives of Doe Run provided an informational 

presentation as well as safety information. Following the presentation, EPA and Doe Run 

representatives walked through the smelting operation. Persons from the Doe Run Company in 

attendance included the following individuals: 

Aaron Miller, Environmental Management Coordinator 

Rusty Keller, Environmental Manager 

Gary Hughes, Plant Manager 

Also present, was Rob Kaleel of the Illinois EPA. 

Background 

The Doe Run Company at Herculaneum operates a primary lead smelter. Operation at the current 

location began in the 1890’s as the St. Joe Company. It is the only currently operating primary 

lead smelter in the U.S. although there are two facilities in Canada and one in Mexico. Ore 

concentrate from Doe Run’s 6 lead mines is processed at the Herculaneum primary lead facility. 

Until about 2003, Doe Run operated a second primary lead smelter at Glover, MO. In 2003, the 

Glover primary lead smelting operations were suspended. The mineral galena (Missouri’s State 

mineral) is mined from the Virburnum Trend, which is valued for the relatively small amounts of 

impurities, mostly trace amounts of copper, silver and zinc. The facility produces little or no pure 

lead as a final product; instead they produce lead alloys based on customer specifications. The 

alloyed lead is used in making lead-acid batteries for automobiles, backup power supplies, cell 

towers components, machine counterweights, computer linings, and crystal. 

The Herculaneum facility is the only operating primary lead smelter in the U.S. and has a 

nameplate capacity of 250,000 ton/yr, although the State Implementation Plan (SIP) limits 

production to 113,000 tons/yr in 2009. This is to be increased to 130,000 tons/yr in 2010. Due to 

the new NAAQS for lead, which was lowered from 1.5 ug/m3 to 0.15 ug/m3, and SO2, the plant 

will cease lead metal production by about 2015. The plan is to replace the current 

pyrometallurgical process at Herculaneum with a hydrometallurgical process (Flubor process) at 

its facility in Glover, MO. They also sell lead ore concentrate to China and will consider 

continuing this practice even after the Herculaneum facility ceases lead production. 

Process Description 

The facility is a primary lead smelter. Lead concentrate, which contains approximately 75% lead 

by weight and a moisture content of 6-10% is carried by trucks from Doe Run’s mine/mills and 

delivered to the storage area at the Herculaneum facility. The ore concentrate storage area is 

contained by a block wall several feet high to minimize wind disturbance of the pile, although 

the size of the ore concentrate is like beach sand and the concentrate is heavy enough that it is 

not easily entrained. Fluxing materials (silica, limestone, mill scale) are stored in the same 

general area. The concentrate is transferred to a car that moves by rail to the sinter building. The 

rail car is moved inside the building and tipped into a hopper, and removed from the building. 
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Fluxing materials are similarly transferred to the sinter building. The concentrate and fluxing 

material are crushed and mixed before entering the sinter machine. 

The function of the sinter machine is to roast the ore concentrate in order to drive off the sulfur. 

In the sintering machine, a thin layer of sinter is layered over a slotted belt that is several feet 

wide. The sinter is ignited using a gas flame from above while air is drawn down through the 

belt. As the belt advances, ore concentrate is placed on top of the burning sinter to a depth of 

approximately 9 inches. Air is blown from below to help ignite the ore concentrates. 

Temperatures in the sinter machine are approximately 1300 F. This roasting process is necessary 

to remove the sulfur from the concentrate before it can be processed further. The nameplate 

capacity of the sinter machine is 100 tons/hr. 

The sulfur is exhausted from the sinter machine as SO2. The SO2 exhaust is first treated by an 

ESP before entering the acid plant where most of the SO2 is converted to sulfuric acid. 

Sinter and coke are charged at the top of one of two blast furnaces while air is blown in at the 

bottom of the blast furnace. Molten lead exits from the bottom of the blast furnace and is 

transferred to the drossing plant in pots using overhead cranes. Slag is also tapped from the blast 

furnace and is fed back to the sinter machine or placed in storage. 

From the blast furnace, the lead bullion goes through drossing to remove copper. In drossing, the 

lead bullion is cooled gradually to allow the copper to separate from the lead which can then be 

skimmed off. The lead is approximately 97% pure at this point. The lead bullion is transferred to 

refining kettles for the removal of silver and zinc. Zinc is added for the removal of silver. 

Finally, the zinc is removed. The lead is refined until it attains a lead concentration of 99.99%. 

At this stage, the lead is alloyed based on customer specifications and cast into ingots. Some lead 

ingots go to the strip rolling mill and are rolled out into thin sheets per customer specifications. 

Environmental Controls 

To control emissions of lead from the smelting operation, various enclosures, work practices, 

baghouses, electrostatic precipitators and scrubbers are used. They have installed over 60 

engineering controls in response to the states’ SIP for lead and in an effort to reduce their 

emissions down to 0.5 ug/m3. As a result of their efforts, they were able to meet the NAAQS 

lead standard of 1.5 ug/m3 most of the time. 

Plant wide. Sprinklers are located throughout much of the plant facility and operate 

intermittently to keep roadways and other areas subject to vehicle traffic wet in order to suppress 

dust. Wetting operations are suspended when the outdoor temperature drops to 39 oF. A 

regenerative sweep, which uses a vacuum and HEPA system, is driven around the facility 

roadways to remove surface dust and debris. 

Concentrate Storage. A moisture content of at least 6% is maintained in the lead ore 

concentrate. The concentrate is stored in a walled area to minimize wind effects. Delivery truck 

loads are covered with tarps and, before leaving, are washed to remove materials from the truck 

and tires. Materials are transferred from the hopper to the rail car through a sleeve that extends 

down to the railcar that helps slow down the material and reduce dust emissions. Limits are also 
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placed on the number of times each day that certain activities in the storage area can occur as 

well as restricting the hours of their occurrence. 

Enclosures. The area in which the railcar is tipped and unloaded has been enclosed so that the 

tipping process takes place in an enclosed building. Doors have been placed on other buildings 

and required to be kept closed. Buildings enclosing the sinter machine, blast furnace and refining 

section are kept under negative pressure to keep the flow of air into the building. 

Air Pollution Control Devices. Baghouses are used to control lead emissions from buildings 

and process equipment. The sinter machine is controlled by baghouse no. 3. The blast furnace 

top is controlled by baghouse no. 6; the front of the blast furnace is controlled by a separate 

baghouse (no. 5). In addition, the blast furnace is enclosed in a building and ventilated to a 

300,000 acfm baghouse (no. 9), although the baghouse is designed to operate up to 500,000 

acfm. The refinery process is enclosed in a building and ventilated to a 250,000 acfm baghouse 

(no.7). The kettle area is ventilated to a separate baghouse (no. 8). Exhaust gases from sintering 

are treated by an ESP before entering the acid plant where SO2 is removed and recovered as 

sulfuric acid. 

Water Quality. All water runoff from the plant is sent to a thickener settling tank, filter press 

and PH adjustment before discharge. 

4. Southeast Missouri Mining and Milling (SEMO) Division, West Fork, Missouri, 

October 20, 2009 

At the Doe Run SEMO Division facility, representatives presented information on the mining 

and milling operations of the Doe Run Company. Following the presentation, EPA and Doe Run 

representatives visited the mine and mill site in West Fork. Persons from the Doe Run Company 

in attendance included the following individuals: 

Bill Lane, VP Research and Technology Development 

Clifford Asbury, Environmental Manager 

Bob Roscoe, VP of Mining and General Manager 

Dennis Murphy, SEMO Safety and Environmental Manager 

Dave Ocun, Manager Technology Development 

Vanessa Eckhoff (?), Title? 

John _______, Engitec Technologies, Italy 

Background 

Current mining operations are conducted in the Viburnum Trend and have been mined for about 

50 years, with over 300 million tons total mined. The Viburnum Trend is 40 miles in length. Doe 

Run mining operations employ about 750 workers. 

Ore from the mines are transferred to the milling operations where the ore is concentrated and 

readied for smelting. Recent production figures for the mines are as follows: 
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 Ore mined – 5 million tons/yr 

 Lead concentrate produced – 280,000 tons/yr 

 Zinc from concentration – 65,000 tons/yr 

 Copper from concentrate – 20,000 tons/yr 

Ores from SEMO are considered “clean” in that they only contain lead, zinc, and copper unlike 

ores from other locations that can contain contaminants such as arsenic, bismuth, and antimony. 

Because they do not contain these other metals, Doe Run ore concentrate are in demand 

worldwide. Approximately 70% of the ore concentrate goes to Doe Run’s primary smelter at 

Herculaneum. The rest goes to the SEMO port, which is a state-of-the-art facility for handling 

concentrate, especially lead concentrate. The copper concentrate goes to a copper smelter in 

Canada. 

Doe Run is carrying out remediation operations at their former mining and milling operations 

that were located in the old lead belt. Chat and tailings piles at those locations contain less than 

0.1% lead. 

Doe Run supplies about 70% of the lead ore concentrate consumed in the United States. The Red 

Dog zinc mine in Alaska produces lead as a byproduct of their zinc process. A silver mine in 

Idaho also produces a lead ore concentrate. 

Process Description 

All of the mining operations are underground. The ore bodies range in thickness from a few 

inches to 120 feet. The host rock is a dolomitic limestone and is very stable for their underground 

mining room and pillar operations. Useful ore is about 4 -10% of the rock mined; the rest is 

dolomite. Mine depths range from 500 to 1,200 feet below grade with the total length of tunnels 

in current mines of 20 – 30 miles. In the mining operations, rock is broken by blasting. Initial 

primary crushing operations are typically underground and reduce the rock size from about 24 

inches down to 6 inches. At some mines, primary crushing is done after the rock is hauled to the 

surface. 

In milling, the rock is subjected to secondary and tertiary grinding to reduce the size of the 

material to allow the physical separation of the lead (galena), zinc (spharite) and copper ores. 

The fine ores are then transferred to the flotation circuit. 

In the flotation circuit, concentrates of lead, zinc and copper are produced. The flotation circuit 

recovers about 95% of the lead, 75% of the zinc, and 50% of the copper. Additional grinding 

(secondary grinding) takes place in a Rod Mill then a Ball Mill before the ore is subjected to 

flotation. In flotation, chemical additives cause the lead and copper to adhere to bubbles 

generated in the slurry tanks, which then rise to the surface; zinc and dolomite sink and are 

moved to another process. The zinc and dolomite go through another flotation process to 

separate out the zinc; the tailings go to tailings storage. Each product goes to thickening tanks 

where the metals sinks and is then vacuumed filtered to reduce the moisture content down to 

6 – 10%. The ores are loaded into trucks for transport. 
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A brief stop was made at the Brushy Creek Mine and Mill. The mine head and mill building was 

visible. Due to the time required to coordinate a trip down into the mine and to visit the mill, no 

mine or mill tour was conducted. 

5. Flubor Demonstration Project, West Fork, Missouri, October 20, 2009 

Background 

The Doe Run Company sees lead as continuing to be a vital material for the U.S. and the world. 

Besides the current lead-acid batteries used in automobiles, Doe Run sees energy storage systems 

in hybrid vehicles and renewable energy sources (e.g., wind power) as well as emergency backup 

storage systems, to continue to be vital to national interest and security. Seeking a cleaner 

method of producing lead, the Doe Run Company built a demonstration project to test the 

feasibility of a hydrometallurgical process for producing lead metal. The process, called the 

Flubor, process, was developed by Engitec Technology in Italy. Fluboric acid is used to dissolve 

the lead sulfide ore concentrate that allows the separation and concentration of lead. The process 

is patented and proprietary and has yet to be used in the full scale production of lead. Doe Run 

representatives see this hydro-process as the future of lead production where the process 

operation is wet, low temperature and characterized by low volatility in contrast to current pyrotechniques which use high temperatures and result in the volatilization of lead. The Flubor 

process would virtually eliminate lead emissions, would have a smaller carbon footprint and 

would be a sustainable technology. There are currently no Flubor processes being used in metals 

production. According to the Doe Run representatives, the process would be fully contained, 

emit no sulfur, reduce lead emissions by 99.67%, require no heat, and produce no process waste. 

During the visit to the Flubor demonstration project, the process was not operating. 

The Doe Run Company is currently in the process of conducting feasibility and engineering 

studies in order to acquire funding to construct a full scale Flubor process. The plan is to build 

the operation in Glover, Missouri, at the site of a primary smelter that is currently not running. 

Plans are to construct the process in two phases with phase one to start operation in 2012. Each 

phase will be capable of processing about 78,000 tons/yr of ore, with a lead metal output of 

about 60,000 tons/yr. 

Process Description 

The general steps in the Flubor process are leaching, filtering or residue removal, and 

electrowinning. Lead concentrate is dissolved in a water fluboric acid solution. This dissolves the 

lead and oxidizes the sulfur. The solution is filtered to remove the sulfur and zinc components. 

After filtering, the solution goes to the electrowinning unit where an electric current is passed 

through the solution causing the lead to migrate to and coat the cathode. The solution is 

regenerated in the electrowinning process and returned to the leaching reactor to dissolve other 

lead concentrate. A thin lead sheet is used as the cathode material. Using lead as the cathode, the 

entire cathode with the accumulation of lead can then be remelted later. The current plan is to 

remelt the cathode at the Herculaneum smelter, add in the customer specific alloys and cast the 

finished ingots. 
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6. Resource Recycling Division (also known as the Buick Resource Recycling Division), 

Boss, Missouri, October 20, 2009 

At the Doe Run Resource Recycling Division, representatives of the facility provided an 

informational presentation on their recycling operations. Following the presentation, EPA and 

Doe Run representatives toured the recycling operation. Persons from the Resource Recycling 

Division in attendance included the following individuals and others: 

Steve Arnold, General Manager 

James Lanzafame, Environmental and Health Manager 

Barbara Sheppard, Human Resources and Community Relations 

Matt Wool, Doe Run, Council 

Background 

The facility currently has 290 employees. The facility was originally a primary smelter but was 

converted in 1991 to its current operation. They process 14 million batteries/yr, 80% of which 

are batteries used for startup, lighting, and ignition (SLI); 20% are large batteries used in 

missiles, locomotives, and backup supply. It also receives lead paint from abrasive blasting, 

dental x-ray plates, and used cathode ray tube glass. Approximately 160,000 tons of lead are 

recycled annually. This facility is a classified as a hazardous waste facility. A laboratory is onsite 

when it is necessary to analyze incoming shipments for safety reasons. 

Process Description 

Incoming SLI batteries are dumped into a bunker area where the batteries are broken up and 

shredded to liberate the weak sulfuric acid and remove any remaining charge. The acid is used 

later in the process. Some batteries are delivered to the facility in steel drums. These drums are 

shredded and added to the blast furnace. The shredded batteries are moved on a vibrating feeder 

that feeds a conveyor belt into a hammer mill, which reduces the batteries into small pieces. The 

lead and other metal pieces are fed to a reverberatory furnace producing lead and slag (which is 

lead-antimony). This is further treated in a blast furnace to produce lead and slag. The lead is 

transferred to the dross plant, then to refining, alloying and casting. Slag from drossing and 

refining goes to an onsite repository which is permitted as a hazardous waste landfill even 

though the slag is not a hazardous waste. 

Plastic from the process is collected and goes to a recycler. The lead sulfur battery paste is 

treated with a sodium carbonate to form a lead oxide and sodium sulfate. This is processed into a 

food grade sodium sulfate and used as filler in powdered soap. Other U.S. secondary lead 

smelters do not make the sodium sulfate. 

Environmental Controls 

Controls at the facility include a recently added baghouse on the refining building, which was 

added at a cost of $1.4 million. A sweat furnace and blast furnace are controlled by baghouses. 

The steel drum shredder is controlled using baghouses. A lead oxide pug mill used for antimony 

and tin removal are controlled by a baghouse and HEPA filter. They also operate a 425,000 acfm 
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main process baghouse. They have added enclosures, high speed automatic doors, and 

sweeper/vacuum trucks as part of their work practices to reduce fugitive emissions. In 2011 a 

new 160 acfm baghouse is planned for the blast furnace, dross crane building. They also have a 

startup, shutdown, and malfunction plan in place.