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Region 7 Air Program

Serving Iowa, Kansas, Missouri, Nebraska and 9 Tribal Nations


Herculaneum, Missouri, Lead Attainment Plan

Background of the Plan: On June 3, 1986, EPA issued a call for a revision to the Missouri State Implementation Plan (SIP) in response to violations of the National Ambient Air Quality Standard (NAAQS) for lead in the vicinity of the Doe Run primary lead smelter in Herculaneum, Missouri. Doe Run-Herculaneum is the largest primary lead smelter in the United States with a production capacity of 250,000 tons of refined lead per year. The NAAQS for lead is 1.5 micrograms (µg) of lead per cubic meter (m3) of air averaged over a calendar quarter.

Summary of the Plan: The state submitted a SIP revision on September 6, 1990, as well as a revised SIP meeting the Clean Air Act Title I, part D requirements in 1994. The plan established June 30, 1995, as the date by which the Herculaneum area was to have attained the lead standard; a notice of final rulemaking was published on this action on May 5, 1995, (60 FR 2227). However, the plan did not result in attainment of the standard and observed lead concentrations in the Herculaneum area continued to show violations of the standard. Therefore, on August 15, 1997 (62 FR 43647), after taking and responding to public comments, EPA published a notice in the Federal Register finding that the Herculaneum nonattainment area had failed to attain the lead standard by the June 30, 1995, deadline.

On January 10, 2001, Missouri submitted a revised SIP to EPA for the Doe Run-Herculaneum area. The SIP revision was found complete on January 12, 2001. The SIP established August 14, 2002, as the attainment date for the area and satisfied the part D requirements of the Clean Air Act. The revised plan also contains a control strategy to address the violations of the NAAQS which occurred after implementation of the control measures in the 1995 SIP. EPA believes that the dispersion and receptor modeling demonstrate that the selected control measures will result in attainment of the NAAQS for lead.

On April 16, 2002, EPA published a final rule approving the SIP (See 67 FR 18497) submitted by the Missouri Department of Natural Resources (MDNR), establishing the new attainment date for the Herculaneum area to be August 14, 2002. Refer to MDNR's web-site Exit EPA Click for Disclaimer for monthly updated lead monitoring results for the Herculaneum area.

Emission Reductions: The Doe Run-Herculaneum SIP calls for full implementation of the control strategy by July 31, 2002. Implementation of the control strategy will result in approximately a 99 percent reduction in fugitive lead emissions from sources that were fingerprinted as contributing significantly to nonattainment in the Herculaneum area based upon modeling and monitoring activities.

Stationary Source Control Measures: Control measures employed by Doe Run involve engineering modifications to the facility which include: enclosure projects, improved ventilation systems being routed to stacks, improved material handling conveyors, and installation of air pollution control equipment (baghouses). Approximately $8,500,000 will be spent on these projects to control and reduce fugitive air emissions of lead being released from the Blast Furnace/Dross Plant and the Refinery. These sources were targeted through enhanced recepter and dispersion modeling conducted by EPA and MDNR. Approximately 350 lbs/hour of fugitive lead emissions are expected to be eliminated by this control strategy.

Stationary Source Regulations: One stationary source rule, one Consent Judgement, and one Work Practice Manual were approved as part of this plan. These include:

  • 10 CSR 10-6.120 Restriction of Emissions from Lead From Specific Lead Smelter-Refinery Installations
  • Consent Judgement - MDNR
  • Work Practice Manual

Contingency Measures: The state submission specifies an attainment date for the Herculaneum area of August 14, 2002, as set in the state SIP. If the area has a violation of the NAAQS, the contingency controls will be implemented after Doe Run-Herculaneum is notified by EPA and/or MDNR. The following contingency measures were adopted in the event the area violates the lead standard and will be implemented within 6 months following the calendar quarter in which the violation occurred.

  • Modify Cooler Baghouse dilution air intake
  • Modify roof monitor in the Sinter Plant Mixing room with passive filters
  • Enclose railcar fume loading station at No. 5 Baghouse
  • Enclose North End of railcar unloader
  • Enclose North End of No. 1 trestle
  • Modify sinter machine inlet to No. 3 Baghouse within 9 months following the calendar quarter in which the violation occurred

In the event there is a second violation of the quarterly lead standard of 1.5 g/m3 after implementation of the initial contingency measures, Doe Run-Herculaneum is required to curtail production utilizing one of three emission and/or production curtailing methods: Method (1), reduce stack and fugitive emissions by 20 percent, except from the main stack; Method (2), limit production to 50,000 short tons/quarter of refined lead produced; and, Method (3) limit production of refined lead production based upon a prescribed formula.

Doe Run-Herculaneum will also maintain current bids on the materials necessary to implement each contingency measure. Doe Run-Herculaneum also may substitute any such controls if Doe Run-Herculaneum can demonstrate to MDNR and EPA that the alternative control measures would equal or exceed controls in the current SIP.

Additional Information: In an action separate from the SIP in 2001, EPA and MDNR signed an Administrative Order on Consent (AOC) with Doe Run to control and cleanup a wide array of contamination. The AOC was the most comprehensive agreement to date with Doe Run and requires new controls on air emissions, remediation of lead contaminated residential yards, and investigation and stabilization of a contaminated slag pile located in the Mississippi River flood plain.

The Missouri Department of Natural Resources has a website to help citizens find more information on the lead contamination in Herculaneum. Exit EPA Click for Disclaimer

EPA Region 7 Contact: Josh Tapp (913) 551-7606, tapp.joshua@epa.gov

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