2015-13128. Approval and Promulgation of Air Quality Implementation Plans; Missouri; 2013 Missouri State Implementation Plan for the 2008 Lead Standard

AGENCY:

Environmental Protection Agency.

ACTION:

Proposed rule.

SUMMARY:

The Environmental Protection Agency (EPA) proposes to grant full approval of Missouri's attainment demonstration State Implementation Plan (SIP) for the 2008 lead National Ambient Air Quality Standard (NAAQS) nonattainment of the Viburnum Trend area in portions of Iron, Dent and Reynolds Counties, Missouri, submitted on April 18, 2013. EPA believes that the SIP submitted by the State satisfies the applicable requirements of the Clean Air Act (CAA) identified in EPA's Final Rule published on October 15, 2008, and will bring the area into attainment of the 0.15 microgram per cubic meter (ug/m³) lead NAAQS in the Viburnum Trend, Missouri area.

In this action, EPA also proposes approval of a revision to the Missouri SIP to incorporate an amendment to an existing Missouri statute to restrict lead emissions from specific sources. The amendment revises certain throughput and emissions limits applicable to the Doe Run Buick Resource Recycling Facility (BRRF) in the Viburnum Trend lead nonattainment area. Approval of this rule will ensure consistency between the state and Federally-approved rules, and ensure Federal enforceability of the revised state rule. This revision was submitted to EPA on October 30, 2009.

DATES:

Comments must be received on or before July 1, 2015

ADDRESSES:

Submit your comments, identified by Docket ID No. EPA-R07-OAR-2015-0223, by one of the following methods:

1. www.regulations.gov: Follow the on-line instructions for submitting comments.

2. Email: [e-mail].

3. Mail, Hand Delivery or Courier: Stephanie Doolan, Environmental Protection Agency, Air Planning and Development Branch, 11201 Renner Boulevard, Lenexa, Kansas 66219.

Instructions: Direct your comments to Docket ID No. EPA-R07-OAR-2015-0223. EPA's policy is that all comments received will be included in the public docket without change and may be made available online at www.regulations.gov,, including any personal information provided, unless the comment includes information claimed to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Do not submit information that you consider to be CBI or otherwise protected through www.regulations.gov or email. The www.regulations.gov Web site is an “anonymous access” system, which means EPA will not know your identity or contact information unless you provide it in the body of your comment. If you send an email comment directly to EPA without going through www.regulations.gov,, your email address will be automatically captured and included as part of the comment that is placed in the public docket and made available on the Internet. If you submit an electronic comment, EPA recommends that you include your name and other contact information in the body of your comment and with any disk or CD-ROM you submit. If EPA cannot read your comment due to technical difficulties and cannot contact you for clarification, EPA may not be able to consider your comment. Electronic files should avoid the use of special characters, any form of encryption, and be free of any defects or viruses.

Docket. All documents in the electronic docket are listed in the www.regulations.gov index. Although listed in the index, some information is not publicly available, e.g., CBI or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, will be publicly available only in hard copy. Publicly available docket materials are available either electronically in www.regulations.gov or in hard copy at the EPA, Air Planning and Development Branch, 11201 Renner Boulevard, Lenexa, Kansas. EPA requests that you contact the person listed in the FOR FURTHER INFORMATION CONTACT section to schedule your inspection. The interested persons wanting to examine these documents should make an appointment with the office at least 24 hours in advance.

FOR FURTHER INFORMATION CONTACT:

Stephanie Doolan at [phone], or by email at [e-mail].

SUPPLEMENTARY INFORMATION:

Throughout this document “we,” “us,” or “our” refer to EPA.

Table of Contents

I. What is being addressed in this document?

II. Have the requirements for the approval of a SIP revision been met?

III. What action is EPA taking?

IV. Background

V. Technical Review of the Attainment Demonstration SIP Related to the 2008 Lead NAAQS

A. Facility Description

1. BRRF Process Description

2. Mines/Mills Process Description

B. Model Selection, Meteorological and Emissions Inventory Input Data

C. Modeling Results

1. Base Case Analysis

2. Future Case Analysis

D. Control Strategy

E. Reasonably Available Control Measures (RACM) Including Reasonably Available Control Technology (RACT) and Reasonable Further Progress (RFP)

F. Attainment Demonstration

G. New Source Review (NSR)

H. Contingency Measures

I. Enforceability

VI. Review of Revision to Missouri Rule Restricting Lead Emissions From Specific Lead Smelter-Refinery Installations

A. Background

B. Analysis of Production and Emissions Limits

C. Work Practice Manual (WPM)

D. Reporting and Record Keeping

E. Test Methods

VII. Proposed Action

I. What is being addressed in this document?

In this document, EPA is addressing Missouri's attainment demonstration SIP for the 2008 lead NAAQS nonattainment in the Viburnum Trend Missouri area. The applicable standard addressed in this action is the lead NAAQS promulgated by EPA in 2008. EPA believes that the SIP submitted by the state satisfies the applicable requirements of the CAA identified in EPA's Final Rule (73 FR 66964, October 15, 2008), and will bring the area into attainment of the 0.15 microgram per cubic meter (ug/m³) lead NAAQS in the Viburnum Trend lead nonattainment area.

In this action, EPA is also addressing a revision to the Missouri SIP to approve portions of a revision to the State of Missouri Code of State Regulations (CSR) 10-6.120, “Restriction of Emissions of Lead from Specific Lead Smelter-Refinery Installations”. This revision pertains to throughput limits applicable to the BRRF, which is the primary source of lead emissions in the Viburnum Trend nonattainment area. Pursuant to a withdrawal request from Missouri,^[1] EPA is taking action on specific portions Missouri rule 10 CSR 6.120. Missouri rule 10 CSR 6.120, as it pertains to the Buick Resources Recycling Facility, was previously approved in the Missouri SIP. See 69 FR 51953. The Viburnum Trend SIP addressed in this proposed action relies upon portions of the revision to 10 CSR 6.120.

II. Have the requirements for the approval of a SIP revision been met?

The state submission has met the public notice requirements for SIP submissions in accordance with 40 CFR 51.102. The submission also satisfied the completeness criteria of 40 CFR part 51, appendix V. In addition, the revision meets the substantive SIP requirements of the CAA, including section 110 and implementing regulations.

III. What action is EPA taking?

EPA is proposing to grant full approval of Missouri's attainment demonstration SIP for the 2008 lead NAAQS. We are also proposing to approve portions of a revision to Missouri rule 10 CSR 6.120, “Restriction of Emissions of Lead from Specific Lead Smelter-Refinery Installations”. EPA is proposing this action in order to solicit comments. Final rulemaking will occur after consideration of any comments received.

IV. Background

EPA established the NAAQS for lead on October 5, 1978 (43 FR 46246). The 1978 NAAQS for lead is set at a level of 1.5 micrograms per cubic meter (ug/m³) of air, averaged over a calendar quarter. The Viburnum Trend area is designated as attainment for the 1978 lead NAAQS.

On October 15, 2008, EPA established a new lead NAAQS of 0.15 ug/m^[3] in air, measured as a rolling three-month average. (73 FR 66964). On November 22, 2010, the Buick/Viburnum Trend area was designated as nonattainment for the 2008 lead NAAQS. (75 FR 71033).^[2] Under sections 191(a) and 192(a) of the CAA, Missouri is required to submit to EPA an attainment demonstration SIP revision for lead and to demonstrate the nonattainment area will reach attainment of the 2008 lead NAAQS no later than five years from the date of the nonattainment area designation.

Missouri rule 10 CSR 10-6.120 ”Restriction of Emissions of Lead from Specific Lead Smelter—Refinery Installations” establishes lead stack emissions limits and testing and recordkeeping requirements at specific lead smelters including the Herculaneum facility ^[3] in Herculaneum, Missouri, and BRRF in Boss, Missouri. The Buick/Viburnum Trend lead NAAQS attainment SIP relies upon the requirements imposed by Missouri rule 10 CSR 10-6.120, with the exception of those requirements withdrawn by Missouri. In addition, the approval of the production limits for BRRF relies upon the modeling demonstration proposed in the Viburnum Trend area lead NAAQS attainment SIP, therefore, approval of the two SIP revisions are proposed concurrently herein.

V. Technical Review of the Attainment Demonstration SIP Related to the 2008 Lead NAAQS

A. Facility Description

1. BRRF Process Description

There are four lead-emitting sources contributing to the Buick/Viburnum Trend lead nonattainment area: BRRF; the Buick Mine and Mill; the Casteel Mine; and K & D Crushing. BRRF operates as a secondary smelter of lead, lead-containing materials including spent lead acid batteries, lead bullets and shot, lead-containing glass from cathode ray tubes, and lead-based paint chips from lead abatement projects. The Buick Mine and Mill, located to the south of BRRF, conducts subsurface mining and ore processing. The Casteel Mine, located to the north of BRRF, also conducts subsurface mining. K & D Crushing, also located to the north of BRRF, conducts ore crushing at the surface of the Casteel Mine. Crushed and concentrated lead-containing ore was formerly processed at the Herculaneum primary lead smelter, but since that facility ceased primary lead smelting in December 2013, the ore gets shipped out of the U.S. for overseas processing.

As stated above, BRRF is located in the Buick/Viburnum Trend nonattainment area. BRRF's production limit is limited to 175,000 tons of total lead production each year pursuant to Missouri Rule 10 CSR 6.120(3)(B)2. The majority of the lead recycled by BRRF is from spent automotive and industrial batteries.

Lead-bearing items, primarily post-consumer lead-acid batteries, arrive at the facility by truck. Spent batteries are stored in a battery bunker until processed in a shredder. Battery acid (weak sulfuric acid) is drained during shredding, collected in storage tanks and neutralized using calcium hydroxide. The shredded batteries are placed in a vibrating feeder in route to a conveyor belt to the hammer mill. The hammer mill pounds the material into smaller pieces.

Batteries contain metal grids, lead posts, plastic casing and other components, separators and lead sulfate paste. The paste is removed by washing through a set of screens for further processing. The batteries further undergo a separation process under which lead and metal parts are separated from the plastic and other debris. The lead and metal parts are primarily fed to the reverberatory furnace, but also may be fed to the blast furnace. The plastic and other debris are skimmed off and sent to recycling facilities.

The lead sulfate paste is passed through a filter press and neutralized with hydrated lime to form calcium sulfate, then heated at extremely high temperatures in the reverberatory furnace to produce soft antimonial lead bullion and reverberatory slag. Sulfur emissions from the reverberatory furnace are controlled by a dry, flue gas desulfurization scrubber that introduces lime and water to the reverberatory flue gas in a reaction and forms gypsum, which is removed from the gas stream by a polishing baghouse. The reverberatory slag is fed to the blast furnace to recover the antimonial lead. The Missouri SIP submittal contains a process flow diagram that details the emission point sources throughout the process that were included in the modeling.

2. Mines/Mills Process Description

Modeling analysis conducted by Missouri determined that the Buick Mine and Mill, the Casteel Mine, and the K & D Crushing operations contribute significantly to the monitored violation of the 2008 Lead NAAQS at the air monitor. There are other mining and milling operations in the Viburnum Trend area, but these operations were not found to contribute significantly to the Lead NAAQS violation. Emissions from the Doe Run mining and milling operations are primarily in the form of fugitives from the processing of lead containing rock until it becomes a wet concentrate that is shipped to other customers. The process is described in greater detail as follows.

Mining begins with the subsurface drilling and blasting of dolomite rock which contains varying amounts of lead sulfide, zinc sulfide, and copper-iron sulfide minerals. At the Casteel mine, the ore is hauled to the skip pocket “as blasted,” with no underground crushing. At the surface, the coarse ore is crushed by K & D Crushing, a contractor to Doe Run, into smaller pieces. The crushed ore is hauled to other Doe Run facilities, most frequently to the Buick Mine and Mill.

At the Buick Mine and Mill, ore is hauled from the active mining faces to a central crusher where it is crushed down to approximately eight inch pieces. The ore is hoisted to the surface then conveyed to further on-site crushing and screening operations. After being crushed aboveground to less than 5/8-inch in size, the ore subjected to wet milling, and grinding with rods and ball mills until a coarse powder in a wet slurry is produced. The wet slurry further undergoes wet cyclone and floatation separation into lead sulfide, zinc sulfide and copper sulfide components.

The concentrated sulfides further undergo dewatering to produce a concentrate that formerly was shipped to the Herculaneum primary lead smelter. As stated above, the Herculaneum facility ceased operations smelting operations in December 2013; thus, the concentrate is shipped overseas to primary lead smelting operations or to other customers.

B. Model Selection, Meteorological and Emissions Inventory Input Data

Missouri conducted air dispersion modeling to evaluate the effectiveness of the proposed control strategy. The model, AERMOD, was utilized and is EPA's preferred model for demonstrating attainment of the lead NAAQS. AERMOD estimates the combined ambient impact of sources by simulating Gaussian dispersion of emissions plumes. Emission rates, wind speed and direction, atmospheric mixing heights, terrain, plume rise from stack emissions, initial dispersion characteristics of fugitive sources, particle size and density are all factors considered by the model when estimating ambient impacts. Missouri performed two dispersion modeling analyses for the 2008 lead NAAQS for the Viburnum Trend nonattainment area. One was an analysis of current conditions to ensure the model is performing adequately (base case). The second analysis examined the effectiveness of proposed emission controls (future case). The results of these analyses will be discussed in more detail in section V.C. of this document.

Missouri used the meteorological data from the meteorological monitoring station approximately 0.8 miles south of BRRF, co-located with the Buick South non-ambient lead air quality monitor. EPA's preference is for the use of five years of meteorological data to input the model (40 CFR part 51, appendix W, section 8.3.1.2); however, a minimum of one year of representative meteorological data are required. A detailed analysis of the meteorological data collected on-site concluded that only one consecutive year, from August 2009 to July 2010, met the data quality requirements; thus, these surface level data were used to input the model. Wind speed and direction data from the on-site meteorological station were used to input the model, and surface temperature, humidity, and other information from the Farmington, Missouri, National Weather Service observation site were added to the BRRF wind observations. Finally, upper air data from the station at National Weather Service site in Springfield, Missouri, were used to input the model for the parameters including vertical temperature, moisture and wind characteristics of the atmosphere. This data set provided confidence that the controls selected for the attainment demonstration will be effective over a large variety of meteorological conditions. The meteorological data were run through AERMOD's pre-processors to make the data usable by the model.

As required by section 172(c)(3) of the CAA, a revised emission inventory was developed for this nonattainment area. Hourly emissions data from January 2009 to October 2010 from BRRF and the Buick Mine and Mill were used to model the base case. Beginning in late 2010, construction of emission control projects to control fugitive lead dust and sulfur dioxide (SO₂) impacted the base case emissions and ambient air monitoring data, making them no longer representative of pre-control conditions. Emissions represented in the model are from release points, stack emissions validated by stack test data, and fugitive emissions calculated using field measurements wherever possible or estimated based on EPA's AP-42 guidelines.^[4]

The 2011 lead emission totals for Viburnum Trend nonattainment area are listed in Table 1 below. As discussed above, the emissions from the other mine and mill operations in the Viburnum Trend area were not found to significantly impact the lead concentrations reported at the violating ambient air monitor and therefore are not listed.

Facility name	Site name	2011 Emissions a tons per year (tpy)
BRRF	Buick Smelter	16.87
Doe Run	Buick Mine and Mill	1.07
Doe Run	Casteel Mine	0.2
K & D Crushing	Casteel Mine	0.2
Total Emissions		18.34
a Emissions reported to the Missouri Emissions Inventory System (MoEIS) database which are reported to EPA's National Emissions Inventory (NEI) database, version 1, released September 30, 2013, found at http://www.epa.gov/​ttnchie1/​net/​2011inventory.html.

In accordance with 40 CFR part 51, appendix W, background concentrations must be considered when determining NAAQS compliance. Background concentrations are intended to include impacts attributable to natural sources, nearby sources (excluding the dominant source(s)), and unidentified sources. The calculated background concentration includes all sources of lead not already included in the model run script. The background concentration includes distant sources of lead, which may have originally derived from the mining and milling and smelting operations, or naturally occurring lead in soils that has become re-entrained in the atmosphere.

In general, the background value is calculated by averaging the monitored concentrations at monitor sites outside the area of immediate dominant source impact and on days when the predominant wind direction was not blowing from the dominant source to the monitors. Missouri began with all monitored days and identified days with no measured one-hour average wind direction from the smelter. Each monitor was examined in conjunction with an acceptable wind fan and the concentrations are averaged on days with no predominant winds from the dominant sources. The monitor site chosen for the background determination is the Oates monitor located 4.9 miles south of BRRF. The days selected for the calculation match the model study period.

EPA conducted an independent analysis of the data from the Oates monitor and corresponding wind direction to verify the background concentration calculated by Missouri. Based on its independent analysis, EPA agrees that the calculated value represents a conservative estimate of background during the study period. Additional information can be found in the Missouri SIP, Section 4.3.

C. Modeling Results

1. Base Case Analysis

As discussed above, Missouri used the AERMOD dispersion model to run two analyses, the base case and the future case. The base case evaluated a reasonable estimate of maximum potential emissions to account for contributing sources based on normal facility operations. The base case model analysis used monitoring, emissions and meteorological data from August 2009 through July 2010.

Results from the base case modeling were compared with actual monitoring data from the same time period to examine the reliability of the model. The statistical analysis was conducted using the coefficient of correlation, or R². The correlation between modeling outputs under the base case and monitoring data was 0.8551 or greater, with 1.0 indicating 1:1 correlation, confirms the accuracy and reliability of the model's inputs and results. EPA agrees with Missouri's determination that the model is sufficiently reliable to predict that the control measures modeled in the attainment demonstration (see paragraph 5.C.2 Future Case Analysis below) will result in monitored values below the 2008 Lead NAAQS.

2. Future Case Analysis

The future case analysis evaluated the control strategies of the 2013 SIP revision pursuant to the existing Federally enforceable requirements that are applicable to the facility as well as the enforceable 2013 Consent Judgment between Missouri, BRRF and Doe Run. See appendix M, Missouri SIP. The future case dispersion modeling is the attainment demonstration used to verify that the proposed control strategies will bring the Buick/Viburnum Trend lead nonattainment area into compliance with the 2008 lead NAAQS.

The differences between the base and future case emissions rates are based on the changes to the operations resulting from implementation of the control measures required by the 2013 Consent Judgment. The control measures are discussed in paragraph V.D, Control Strategy, below.

Many of the emissions reduction projects that are necessary to meet the 2008 Lead NAAQS were also required to be implemented by January 6, 2014, for compliance with the National Emissions Standard for Hazardous Air Pollutants (NESHAP) for Secondary Lead Smelting (77 FR 556, January 5, 2012). The Secondary Lead NESHAP, applicable to BRRF, requires, among other things, total enclosure and ventilation of lead processing and handling buildings to a negative pressure requirement of 0.02 millimeters of mercury (mm Hg) and housekeeping procedures to reduce fugitive lead-containing dust.

The secondary lead NESHAP, as fully implemented, is expected to result in a building capture efficiency of approximately 95 percent. EPA has allowed facilities to assume, on a site-specific basis, a building fugitive capture efficiency of greater than 95 percent upon demonstration that control measures exceed the requirements of the secondary lead NESHAP. In the case of BRRF, upon careful consideration of site-specific control measures, including the use of local exhaust ventilation devices (LEVs) and a demonstrated negative pressure in buildings exceeding 0.02 mm Hg, EPA agreed with Missouri that a building fugitives capture efficiency of 98 percent was appropriate to use in the modeling. This assumed 98 percent building capture efficiency impacts the modeled emissions rates as well as the estimated emissions reductions described in paragraph V.D, Control Strategy, below. A more detailed discussion of the building fugitives capture efficiency discussion may be found in section 6.2 of Missouri's SIP revision.

The emissions rate reductions are expected to result in a monitored three-month rolling average of 0.128 µg/m³ lead or less at the nearest ambient monitoring location. When added to the background concentration of 0.20 µg/m³, the predicted maximum three-month rolling average lead concentration is 0.148 µg/m³. By comparison, the 2008 Lead NAAQS is 0.150 µg/m³. Therefore, Missouri's modeling demonstrates attainment of the standard.

EPA conducted an independent analysis to verify the predictions of Missouri's modeling. EPA agrees with the modeling conducted by Missouri for its future case analysis.

D. Control Strategy

In order to bring the Viburnum Trend Area into attainment of the 2008 Lead NAAQS, Missouri developed and modeled a control strategy for point source (e.g., stack) and fugitive emissions from the four significant sources of lead in the nonattainment area. Section 5.1 of the Missouri SIP revision details the control measures and the estimated emissions reductions.

Missouri, Doe Run and BRRF developed a Consent Judgment, found in the Missouri attainment demonstration SIP, appendix M, as a means to establish enforceable emission limits, controls, operating parameters, and contingency measures to reduce lead emissions from point, area, and fugitive lead dust sources in support of achieving attainment of the 2008 lead NAAQS as soon as practicable. The 2013 Consent Judgment was submitted as part of Missouri's SIP for the 2008 lead NAAQS.

A brief description of the BRRF control measures and anticipated emissions reductions is as follows.

a. By February 4, 2013, install a baghouse at the south refinery; this project is expected to reduce emissions by 98 percent.

b. By February 4, 2013, relocate a baghouse from the sweat furnace to the blast furnace storage feed building; this project is expected to reduce emissions by 80 percent by totally enclosing the blast furnace feed material storage and handling, while emissions from the main stack will experience a slight increase from the relocation.

c. By February 4, 2013, remove the rotary melter at the north refinery and connection of its baghouse to the north refinery process ducts; this represents an estimated 95 percent reduction in emissions from the previous process configuration.

d. By February 4, 2013, install a truck tire wash system for outbound traffic; washing trucks is anticipated to reduce fugitive emissions by 95 percent.

e. By February 4, 2013, install a pulse-jet baghouse to improve reverberatory furnace process ventilation; this project is expected to reduce reverberatory stack emissions by 45 percent and fugitives by 98 percent.

f. By February 4, 2013, install a dry lime SO₂ scrubber to further process gases as they exit the pulse-jet baghouse; this measure is intended to control SO₂, but will also reduce lead-containing particulates.

g. By January 6, 2014, enclose the refinery, blast furnace, reverberatory furnace and dross plant buildings and install a baghouse to achieve the negative pressure requirement of the Secondary Lead Smelting MACT (40 CFR 63, subpart X); the estimated reduction in overall emissions from these enclosures is expected to by 98 percent.

h. By December 31, 2013, install a 40-foot extension on the breaking separation and neutralization scrubber stack; the elevated stack height provides no net emissions decrease, but rather, greater dispersion of lead emissions that decreases the impact upon receptors within the nonattainment area.

i. By December 31, 2013, construct a 30,000 square foot building extension to the existing blast feed storage building enclosure; the estimated emissions reduction is included in item a. above.

j. By October 31, 2014, install “batwing” style ventilation covers to improve LEV capture efficiencies on refinery kettles; these covers contribute to the 98 percent emissions reduction in item g. above.

k. By December 31, 2013, install quick closing powered doors at the north refinery warehouse, south refinery warehouse, and the entrance to the reverberatory feed storage building; this measure also contributes to the 98 percent reduction in fugitives estimated for item g. above.

These projects have all been completed.

In addition to the control strategies required by the 2013 Consent Judgment, BRRF developed a baghouse Standard Operating Procedure (SOP) and a Work Practice Manual (WPM) to minimize lead emissions from operation and maintenance of all baghouses and to minimize fugitive dust emissions, respectively. The baghouse SOP is required by the Secondary Lead NESHAP and the WPM is required by both the Secondary Lead NESHAP and the Missouri rule 10 CSR 10-6.120. On December 18, 2012, (see appendix J of Missouri's SIP revision) Missouri approved these documents. Although the baghouse SOP and WPM were prepared for compliance with the Secondary Lead NESHAP, and Missouri rule 10 CSR 10-6.120, the activities required therein support the attainment of the 2008 Lead NAAQS as well.

The following is a list of the control measures required by Missouri's 2013 Consent Judgment for the Buick Mine and Mill, and the Casteel Mine. These control measures were implemented by Doe Run on or before June 1, 2013.

a. Modify Buick Mine updraft vents 1, 2, 3 and 6 to achieve a vertical release, defined as 45 degrees from horizontal or greater; this measure improves the dispersion of lead-containing particulates.

b. Preclude public access at the Casteel Mine at a minimum distance provided for in the 2013 Consent Judgment.

c. Preclude public access at Buick Mine updraft vents 1, 2, 3 and 6 at a minimum distance prescribed by the Consent Judgment.

d. Preclude access to the Buick Mine and Mill at a minimum distance prescribed by the 2013 Consent Judgment.

The 2011 Consent Decree between EPA, Missouri and Doe Run also requires enclosure of existing lead-containing material storage areas, interior lead concentrate conveyors, lead filtering system and associated equipment, lead concentrate storage stockpile, and the truck loading area and scale at the Buick Mine and Mill. This project was completed on or before September 1, 2013.

Based on EPA's analysis of the attainment modeling and its outcomes, EPA believes that Missouri's control strategy implemented pursuant to the 2013 Consent Judgment will bring the Viburnum Trend area into attainment of the 2008 Lead NAAQS.

E. Reasonably Available Control Measures (RACM) Including Reasonably Available Control Technology (RACT) and Reasonable Further Progress (RFP)

Section 172(c)(1) of the CAA requires nonattainment areas to implement all RACM, including emissions reductions through the adoption of Reasonably Available Control Technologies (RACT), as expeditiously as practicable. EPA interprets this as requiring all nonattainment areas to consider all available controls and to implement all measures that are determined to be reasonably available, except that measures which will not assist the area to more expeditiously attain the standard are not required to be implemented.^[5] In March 2012, EPA issued guidance titled, “Implementation of Reasonably Available Control Measures (RACM) for Controlling Lead Emissions” (RACM Guidance).^[6]

Section 172(c)(2) of the CAA requires areas designated as nonattainment for criteria pollutants to include a demonstration of Reasonable Further Progress (RFP) in attainment demonstrations. Section 171(1) of the CAA defines RFP as annual incremental reductions in emissions of the relevant air pollutants as required by part D, or emission reductions that may reasonably be required by EPA to ensure attainment of the applicable NAAQS by the applicable date. Part D does not include specific RFP requirements for lead.

Missouri performed a RACM analysis in compliance with the RACM Guidance. As stated in the final lead NAAQS rule, RFP is satisfied by the strict adherence to a compliance schedule which is expected to periodically yield significant emission reductions. Missouri has determined that existing controls and practices, combined with additional controls and practices required by the 2013 Consent Judgment, constitute RACM. The control measures have been modeled and demonstrated to achieve the lead NAAQS and also comply with RACM and RFP.

In accordance with the Consent Judgment, all of the control measures for BRRF and the mines and mills have been installed to date. The secondary lead NESHAP requires BRRF to comply with control measures and work practices on or before January 6, 2014. Further, Missouri rule 10 CSR 10-6.120 requires BRRF to implement the WPM and places production limits on the facility. Collectively, these control measures and practices exceed the requirements of EPA's RACT Guidance.

RFP is addressed by the control strategy occurring in a timeframe consistent with the CAA and the 2013 Consent Judgment. Upon implementation of the control strategy and practices described above, ambient air quality concentrations are expected to drop at or below attainment levels immediately after implementation of the control strategy. Air monitoring data indicate that all of the nonattainment area's ambient air quality monitors reported lead (Pb) concentrations below the 2008 lead NAAQS for the three-month rolling average for February through May 2014. See http://www.dnr.mo.gov/​env/​apcp/​docs/​leadmonitordata.pdf. For the rolling calendar quarter of April through June 2014, and May through July, the Buick North monitor violated the NAAQS due to a power outage on June 22, 2014, that impacted air pollution control equipment. This violation did not trigger contingency measures because the 2013 Consent Judgment does not require the facility to begin monitoring attainment of the lead NAAQS until the rolling calendar quarter following installation of all control measures, which is November 2014 through January 2015. For the rolling calendar quarters starting in July through December 2014, the facility is attaining the lead NAAQS.

EPA proposes to approve Missouri's SIP as meeting sections 172(c)(1) and (c)(2) of the CAA.

F. Attainment Demonstration

CAA section 172 requires a state to submit a plan for each of its nonattainment areas that demonstrates attainment of the applicable ambient air quality standard as expeditiously as practicable, but no later than the specified attainment date. This demonstration should consist of four parts: (1) Technical analyses that locate, identify, and quantify sources of emissions that are contributing to violations of the lead NAAQS; (2) analyses of future year emissions reductions and air quality improvement resulting from already-adopted national, state, and local programs and from potential new state and local measures to meet the RACT, RACM, and RFP requirements in the area; (3) adopted emissions reduction measures with schedules for implementation and (4) contingency measures required under section 172(c)(9) of the CAA.

The requirements for the first two parts are described in the sections on emissions inventories and RACM/RACT, above and in the sections on air quality modeling and the attainment demonstration that follows immediately below. Requirements for the third and fourth parts are described in the sections on the control strategy and the contingency measures, respectively.

As stated in section V.C.2. above, the future case dispersion modeling is the attainment demonstration used to verify that the proposed control strategies will bring the area into attainment. In order to determine whether the planned emission reduction strategies will result in attainment of the NAAQS, the modeled maximum lead air concentration (based on a rolling three-month average) is added to the calculated background lead concentration of 0.020 µg/m³, the predicted maximum three-month rolling average lead concentration is 0.148 µg/m³. By comparison, the 2008 Lead NAAQS is 0.150 µg/m³. Therefore, Missouri's modeling demonstrates attainment of the standard.

G. New Source Review (NSR)

Within the CAA, part D of title I requires SIP submittals to include a permit program for the construction and operation of new and modified major stationary sources. The current definition of nonattainment areas in Missouri, which for lead includes the Viburnum Trend area, is provided in Missouri rule 10 CSR 10-6.020. For installations in a nonattainment area, Missouri rule 10 CSR 10-6.060 requires a permit for construction of, or major modification to, an installation with potential to annually emit one hundred (100) tons or more of a nonattainment pollutant, or a permit for a modification at a major source with potential to annually emit one thousand two hundred (1,200) pounds of lead. Both rules have previously been approved by EPA as part of the SIP, as meeting the requirements of section 173 of the CAA, and EPA implementing rules at 40 CFR 51.165. (78 FR 19602; 78 FR 37457).

H. Contingency Measures

As required by CAA section 172(c)(9), the SIP submittal includes contingency measures to be implemented if EPA determines that the area has failed to make RFP or if the area fails to attain the NAAQS by December 2015. If the air quality data for any three-month rolling period after the implementation of the control measures identified in the 2013 Consent Judgment exceeds the 0.15 ug/m³ three-month rolling average lead standard, BRRF shall implement the contingency measures set forth in the 2013 Consent Judgment. Missouri may also require implementation of contingency measures if Doe Run fails to implement the control strategy projects in accordance with the 2013 Consent Judgment.

The 2013 Consent Judgment contains the following contingency measures which apply to BRRF:

a. Ventilate the reverberatory feed storage building with a minimum design to achieve a negative pressure of 0.02 inches Hg within nine months' notice from Missouri.

b. Within a time frame to be determined by Missouri and BRRF, BRRF shall submit a work plan for a study to determine the best practices and best available control technology to achieve compliance with the 2008 Lead NAAQS. The study shall be completed and submitted to Missouri within 180 days from Missouri's approval of the work plan. Within 60 days from receipt of the study, Missouri shall advise BRRF of whether the projects and timelines for implementation proposed by the study are acceptable. Upon Missouri's approval or 60 days with no comment, the projects identified by the study shall be implemented in accordance with the timeline therein and shall become a fully enforceable part of the 2013 Consent Judgment.

c. Pave inbound truck parking lot within 18 months of notice from Missouri of a 2008 Lead NAAQS violation.

d. Within a timeframe to be developed by Missouri and BRRF, BRRF shall submit and evaluation of the main baghouse capacity and will identify any projects that are deemed technically feasible and cost-effective to redistribute any excess capacity identified in the evaluation and for inclusion as contingency measures and provide an implementation timeframe. Within 60 days of receipt of the evaluation, Missouri will advise BRRF whether the projects and timelines are acceptable. Upon approval or after 60 days, the projects identified in the baghouse capacity study shall become an enforceable part of the 2013 Consent Judgment.

The contingency measures listed above shall be implemented upon notice from Missouri of a Lead NAAQS violation and shall be implemented in the order listed above for each subsequent Lead NAAQS violation should additional violations occur.

BRRF must notify Missouri within ten (10) days of completion of any contingency measure. Sixty days (60) after completion, BRRF will propose an additional qualified contingency measure to be added to the 2013 Consent Judgment, which will become part of the 2013 Consent Judgment and fully enforceable upon approval by Missouri. These additional contingency measures will also be subject to EPA approval as part of the SIP.

Doe Run or BRRF may also substitute new control(s) for the identified contingency measure(s) if Doe Run or BRRF identifies and demonstrates to Missouri and EPA's satisfaction that the alternative control measure(s) would achieve attainment with the 2008 lead NAAQS. The 2013 Consent Judgment also allows Doe Run or BRRF to change the order of implementation for contingency measures and time frames for completion upon approval by Missouri.

Changes to contingency measures would require a public hearing at the state level and EPA approval as a formal SIP revision. Until such time as EPA approves any substitute measure, the measures included in the approved SIP will be the enforceable measure. EPA does not intend to approve any substitutions that cannot be implemented in the same timeframe as the original measure. These measures will help ensure compliance with the 2008 lead NAAQS as well as meet the requirements of section 172(c)(9) of the CAA. EPA proposes to approve Missouri's SIP as meeting section 172(c)(9) of the CAA.

I. Enforceability

As specified in section 172(c)(6) and section 110(a)(2)(A) of the CAA, and 57 FR 13556, all measures and other elements in the SIP must be enforceable by the state and EPA. The enforceable document included in Missouri's SIP submittal is the 2013 Consent Judgment. The 2013 Consent Judgment contains all control and contingency measures with enforceable dates for implementation. The only exception relates to the Federally enforceable dates found in the 2011 Consent Decree. The 2013 Consent Judgment also includes monitoring, recordkeeping, and reporting requirements to ensure that the control and contingency measures are met. The state adopted the 2013 Consent Judgment into Missouri's state regulations on June 19, 2013, making it state-enforceable. Upon EPA approval of the SIP submission, the 2013 Consent Judgment will become state and Federally enforceable, and enforceable by citizens under section 304 of the CAA.

We note that the 2013 Consent Judgment also contains provisions for stipulated penalties should Doe Run or BRRF fail to comply with provisions of the 2013 Consent Judgment. The 2011 Consent Decree also contains stipulated penalty provisions. EPA is not bound by the state's 2013 Consent Judgment penalties. With regard to matters that are addressed by the 2011 Consent Decree, EPA may enforce against violations of this document under section 113 of the CAA or other Federal authorities, rather than the 2013 Consent Judgment, if EPA approves the 2013 Consent Judgment, as proposed in this action, into the SIP.

EPA proposes to approve Missouri's SIP as meeting sections 172(c)(6) and 110(a)(2)(A) of the CAA, and 57 FR 13556.

VI. Review of Revision to Missouri Rule Restricting Lead Emissions From Specific Lead Smelter-Refinery Installations

A. Background

Section 110 of the CAA requires states to develop air pollution regulations and control strategies to ensure that state air quality meets the NAAQS established by EPA. In order for the state regulations to be incorporated into the Federally-enforceable SIP, states must formally adopt the regulations and control strategies consistent with state and Federal requirements. States submit adopted rules and revisions to EPA for inclusion in the SIP. State rules and revisions approved by EPA under section 110 authority are incorporated into the Federally-approved and enforceable SIP.

As discussed above in paragraph I, Background, Missouri rule 10 CSR 10-6.120 “Restriction of Emissions of Lead from Specific Lead Smelter—Refinery Installations”, establishes lead emissions limits from stacks at specific lead smelters including the Herculaneum facility in Herculaneum, Missouri, and BRRF in Boss, Missouri.

For enforceability, the Viburnum Trend area lead NAAQS attainment SIP relies upon the production limit imposed by Missouri rule 10 CSR 10-6.120, recordkeeping requirements, and test methods. The approval of the revision to the rule relies upon the modeling demonstration proposed in the lead NAAQS attainment SIP to demonstrate that the production limits will result in emissions limits that meet the standard. A technical analysis of the production limits proposed, reporting and recordkeeping requirements, and the test methods prescribed is conducted in the EPA Technical Support Document (TSD), which is included in the docket as materials relied upon for this proposed action. An abbreviated discussion of the information in the EPA TSD is discussed below.

B. Analysis of Production and Emissions Limits

As stated above, Missouri rule 10 CSR 10-6.120(B)(2) limits production at BRRF to 175,000 tons of Pb per year, and is consistent with the limit imposed by the Prevention of Significant Deterioration (PSD) permit issued to the facility. However, the Pb emissions from the present operations are significantly less than the previous operational configuration in the PSD permit. This is due to the elimination of the Rotary Melter, and the addition of control measures listed in Section 5.1 of the SIP document, including two new baghouses, enclosure of the facility's process and materials handling areas under negative pressure to achieve the Secondary Lead NESHAP, and additional work practice standards also to comply with the NESHAP.

The Viburnum Trend area lead NAAQS attainment SIP and supporting Consent Judgment specify Stack Emission Limits required to attain the 2008 Pb NAAQS (see table 4, Stack Emission Limits). Although Missouri rule 10 CSR 10-6.120 establishes the maximum Pb production limit for BRRF rather than a specific emission limitation by stack, the Pb production limit, or throughput, correlates with the stack emission limits modeled in the SIP. The emissions limits by source are detailed in appendix H of the attainment demonstration SIP.

The modeled total emissions in the attainment demonstration SIP are 176,482 tons of Pb produced per year. Thus, the “Future” case modeling demonstrates that under conservative production rates (i.e., slightly higher than the maximum allowable by the revised Missouri rule), the facility still attains the 2008 Pb NAAQS.

As discussed in paragraph V.C. above, EPA has conducted an independent analysis of Missouri's attainment SIP modeling and has determined that the control measures will result in attainment of the 2008 lead NAAQS. The detailed analysis, contained in EPA's TSD, of the Pb production limits for BRRF imposed by Missouri rule 10 CSR 10-6.120 demonstrates that they correspond with the SIP control measures, expressed as stack emission limits, imposed by the Viburnum Trend area lead NAAQS attainment SIP and supporting Consent Judgment and will provide for attainment of the 2008 Pb NAAQS. As demonstrated above, the revision to the Missouri SIP does not interfere with attainment and reasonable further progress.

Pursuant to the March 4, 2015, withdrawal request from Missouri, EPA is not taking action on Missouri rule 10 CSR 10-6.120, General Provision (3)(B)1, which limits main stack, number 7 and 9 baghouse stack and number 8 baghouse stack lead emissions at the Doe Run primary lead smelter-refinery in Herculaneum, Missouri.^[7] In addition, EPA is not taking action on Missouri rule 10 CSR 10-6.120, General Provision (3)(B)2., which limits main stack lead emissions at BRRF to 0.00087 grains per dry standard cubic feet (gr/dscf) of air. Missouri has withdrawn its request for approval of these limits into the SIP because they no longer represent operating conditions at the facility and are higher than the secondary lead NESHAP, respectively.

C. Work Practice Manual (WPM)

Missouri rule 10 CSR 10-6.120(3)(C) contains the requirements for both the Herculaneum facility and BRRF to control fugitive emissions of lead from all process and area sources by work practices. The work practices are required to be submitted to the state in the form of a WPM for the state director's review and approval.

Any change to the WPM requires state director approval and the change shall not lessen the effectiveness of the fugitive emission reductions for the work practice involved. Written approval by the director is required before any change becomes effective.

If the director determines that a change in the WPM is warranted, the state director shall notify the facility in writing. The facility must make the required change(s) within 30 days of written notice from the state director.

The requirements for the WPM are consistent with the modeled controls of fugitive emissions in the Viburnum Trend area attainment SIP. The SIP relies on the Missouri rule for implementation of work practices contained in the approved manual. Therefore, EPA proposes to approve this portion of Missouri rule 10 CSR 10-6.120.

D. Reporting and Record Keeping

Missouri rule 10 CSR 10-6.120(4) contains the requirement for the Herculaneum facility and BRRF to keep records and files generated by the WPM's implementation. The required records include records of inspections conducted of fugitive emissions control equipment such as hoods, air ducts and exhaust fans, and records that demonstrate compliance with the sampling methods required for stack testing discussed below. These records are required to be maintained at the facility for a minimum of two (2) years and shall be made available to the state director upon request.

The requirements for the reporting and record keeping are necessary to determine that the facility is operating in accordance with the modeled controls of fugitive emissions in the Viburnum Trend area attainment SIP. The SIP relies on the Missouri rule for implementation of work practices contained in the approved manual which are documented by the reporting and record keeping requirements contained therein. Therefore, EPA proposes to approve this portion of Missouri rule 10 CSR 10-6.120.

E. Test Methods

Missouri rule 10 CSR 10-6.120(5) contains the required test methods for stack testing in accordance with the requirements for visible emissions contained in Missouri rule 10 CSR 10-6.030(9), for quantifying Pb in stack gases in accordance with Missouri rule 10 CSR 10-6.030(12), and for measuring Pb in ambient air in accordance with Missouri rule 10 CSR 10-030(12). These methods have all been determined to comply with the equivalent EPA Methods 12 and 29 promulgated by 40 CFR part 60 appendix A.

The Test Methods required by the revised Missouri rule are necessary to determine that the facility is complying with the stack emission limits imposed by the Viburnum Trend Area attainment SIP. The SIP relies on the Missouri rule for the Test Methods and reporting of the results of testing to determine compliance. Therefore, EPA proposes to approve this portion of Missouri rule 10 CSR 10-6.120.

VII. Proposed Action

EPA is proposing to grant full approval of Missouri's attainment demonstration SIP for the Viburnum Trend 2008 lead NAAQS nonattainment area. EPA believes that the SIP submitted by Missouri satisfies the applicable requirements of the CAA identified in EPA's Final Rule (73 FR 66964, October 15, 2008), and will result in attainment of the 0.15 ug/m³ standard in the Viburnum Trend, Missouri, area.

Pursuant to Missouri's March 4, 2015, withdrawal request, EPA is not taking action on the Doe Run primary lead smelter-refinery emissions limits in 10 CSR 10-6.120(3)(B)1. and table I, and the 0.00087 gr/dscf main stack emissions limit for BRRF in 10 CSR 10-6.120(3)(B)2. EPA proposes to approve the remaining portions of the revision to Missouri rule 10 CSR 10-6.120 as part of Missouri's SIP.

Statutory and Executive Order Reviews

In this action, EPA is proposing to include in a final EPA rule regulatory text that includes incorporation by reference. In accordance with the requirements of 1 CFR 51.5, EPA is proposing to incorporate by reference Missouri Rule 10 CSR 10-6.120 (with the exclusions of Paragraph 10-6.120 (3)(B)1. and Table 1, and the 0.00087 gr/dscf main stack emissions limit for BRRF) described in the proposed amendments to 40 CFR part 52 set forth below. EPA has made, and will continue to make, these documents generally available electronically through www.regulations.gov and/or in hard copy at the appropriate EPA office (see the ADDRESSES section of this preamble for more information).

Under Executive Order 12866 (58 FR 51735, October 4, 1993), this action is not a “significant regulatory action” and therefore is not subject to review under Executive Orders 12866 and 13563 (76 FR 3821, January 21, 2011). This action is also not subject to Executive Order 13211, “Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use” (66 FR 28355, May 22, 2001). This action merely approves state law as meeting Federal requirements and imposes no additional requirements beyond those imposed by state law. Accordingly, the Administrator certifies that this rulemaking will not have a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.). Because this rulemaking would approve pre-existing requirements under state law and does not impose any additional enforceable duty beyond that required by state law, it does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4).

The SIP is not approved to apply on any Indian reservation land or in any other area where EPA or an Indian tribe has demonstrated that a tribe has jurisdiction. In those areas of Indian country, the rule does not have tribal implications and will not impose substantial direct costs on tribal governments or preempt tribal law as specified by Executive Order 13175 (65 FR 67249, November 9, 2000).

This action also does not have Federalism implications because it does not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government, as specified in Executive Order 13132 (64 FR 43255, August 10, 1999). Thus Executive Order 13132 does not apply to this action. This action merely approves a state rule implementing a Federal standard, and does not alter the relationship or the distribution of power and responsibilities established in the CAA. This rulemaking also is not subject to Executive Order 13045, “Protection of Children from Environmental Health Risks and Safety Risks” (62 FR 19885, April 23, 1997) because it approves a state rule implementing a Federal standard.

In reviewing SIP submissions, EPA's role is to approve state choices, provided that they meet the criteria of the CAA. In this context, in the absence of a prior existing requirement for the State to use voluntary consensus standards (VCS), EPA has no authority to disapprove a state submission for failure to use VCS. It would thus be inconsistent with applicable law for EPA when it reviews a state submission, to use VCS in place of a state submission that otherwise satisfies the provisions of the CAA. Thus, the requirements of section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) do not apply. This action does not impose an information collection burden under the provisions of the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.). Burden is defined at 5 CFR 1320.3(b).

The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the Small Business Regulatory Enforcement Fairness Act of 1996, generally provides that before a rule may take effect, the agency promulgating the rule must submit a rule report, which includes a copy of the rule, to each House of the Congress and to the Comptroller General of the United States. EPA will submit a report containing this proposed rule and other required information to the U.S. Senate, the U.S. House of Representatives, and the Comptroller General of the United States prior to publication of the rule in the Federal Register.

A major rule cannot take effect until 60 days after it is published in the Federal Register. This action is not a “major rule” as defined by 5 U.S.C. 804(2).

Under section 307(b)(1) of the CAA, petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by July 31, 2015. Filing a petition for reconsideration by the Administrator of this proposed rule does not affect the finality of this rulemaking for the purposes of judicial review nor does it extend the time within which a petition for judicial review may be filed, and shall not postpone the effectiveness of such future rule or action.

List of Subjects in 40 CFR Part 52

• Environmental protection
• Air pollution control
• Carbon monoxide
• Incorporation by reference
• Intergovernmental relations
• Nitrogen dioxide
• Ozone
• Particulate matter
• Reporting and recordkeeping requirements
• Sulfur oxides
• Volatile organic compounds

Dated: May 19, 2015.

Mark Hague,

Acting Regional Administrator, Region 7.

For the reasons stated in the preamble, the EPA proposes to amend 40 CFR part 52 as set forth below:

PART 52—APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

1. The authority citation for part 52 continues to read as follows:

Authority: 42 U.S.C. 7401 et seq.

Subpart AA—Missouri

2. In § 52. 1320 amend the table in paragraph (c) by revising the entry for Missouri Rule 10 CSR 10-6.120 and the table in paragraph (d) by adding new entry (29) to read as follows:

§ 52.1320

Identification of plan.

* * * * *

(c) * * *

EPA-Approved Missouri Regulations

Missouri citation	Title	State effective date	EPA approval date	Explanation
Missouri Department of Natural Resources
*         *         *         *         *         *         *
Chapter 6—Air Quality Standards, Definitions, Sampling and Reference Methods, and Air Pollution Control Regulations for the State of Missouri
*         *         *         *         *         *         *
10-6.120	Restriction of Emissions of Lead from Specific Lead Smelter-Refinery Installations	3/30/09	6/1/15 and [Insert Federal Register citation]	Paragraph (3)(B)1 and Table, Provision Pertaining to Limitations of Lead Emissions from Specific Installations, is not approved as part of the SIP. The requirement to limit main stack lead emissions at BRRF to 0.00087 gr/dscf lead in Paragraph (3)(B)2 is not approved as part of the SIP.
*         *         *         *         *         *         *

* * * * *

(d) * * *

EPA-Approved Missouri Source-Specific Permits and Orders

Name of source	Order/permit number	State effective date	EPA approval date	Explanation
*         *         *         *         *         *         *
(29) Doe Run Buick Resource Recycling Facility	Consent Judgment 13IR-CC00016	7/29/13	6/1/15 and [Insert Federal Register citation]

* * * * *

Footnotes

1.  See email from Wendy Vit, Air Quality Planning Section Chief for the Missouri Department of Natural Resources, to Michael Jay, Chief of Atmospheric Programs Section, Air Planning and Development Branch of EPA Region 7, dated March 4, 2015, available in the Docket.

2.  EPA also designated city of Herculaneum, Missouri, as nonattainment for the 2008 lead NAAQS. 75 FR 71033. This nonattainment area has been addressed in a separate action. 79 FR 62574.

3.  The former Herculaneum primary lead smelter ceased lead smelting operations on December 31, 2013, pursuant to the terms of the Consent Decree applicable to the Herculaneum facility entered into by Doe Run, Missouri, and EPA in the United States District Court in the Eastern District of Missouri, Case No. 4:10-cv-01895-JCH (2011 Consent Decree) on December 21, 2011.

4.  AP-42, Compilation of Air Pollutant Emission Factors, Fifth Edition, http://www.epa.gov/​ttnchie1/​ap42/​.

5.  See 58 FR 67751, December 22 1993, for a discussion of this interpretation as it relates to lead.

6.  http://www.epa.gov/​oar/​lead/​pdfs/​2012ImplementationGuide.pdf.

7.  Missouri's State Implementation Plan for the Jefferson County Lead Nonattainment Area and associated lead emissions limits for ongoing refinery operations at the Doe Run Refinery in Herculaneum, Missouri were approved by EPA on October 20, 2014. 79 FR 62574.