DRAFT DOCUMENT FOR OMB REVIEW DATED 10/26/2011

MEMORANDUM

TO: Conrad Chin, U.S. Environmental Protection Agency, OAQPS

FROM: Brad Nelson, EC/R

DATE : September 19, 2011

SUBJECT: Surrogate for Metal HAP Emissions for the Ferroalloys Source Category

The purpose of this memorandum is to establish whether the emissions of particulate matter (PM) can be used as a surrogate for 

### non
- Hg metallic hazardous air pollutants (HAP) emissions from electric arc furn aces (EAF) for the ferroalloys production industry

. The metallic HAP emissions from this source include: arsenic, chromium, chromium VI, lead, manganese, mercury, and nickel. Since the majority of the HAP emissions from the EAF are particulate , establish ing individual emission limits for each of the metallic HAP species emitted from th is sources would be impractical. Measuring each individual metallic HAP would be costly and would pose unreasonable compliance and monitoring burden on the regulated commun ity. In addition, EPA and state compliance oversight and enforcement efforts would also be unreasonably costly without concurrent benefits. Of greater significance, as explained below, the use of PM as a surrogate for HAP metals meets the test establishe d in National Lime II

. Therefore , it is proposed to control 

### non
- Hg metallic HAP using limits on the flue gas concentration of PM as a 

### non
- Hg metallic HAP surrogate.

1.0 Background
The ferroalloys production source category is currently being reviewed as part of the “risk a nd technology” (RTR) review for maximum achievable control technology (MACT standards. Under the "technology review" provision of CAA section 112, EPA is required to review MACT standards and to revise them "as necessary (taking into ac count developments in practices, processes and control technologies)" no less frequently than every 8 years. Under the "residual risk" provision of the CAA section 112, EPA must evaluate the MACT standards within 8 years after promulgation and promulgate standards if required to provide an ample margin of safety to protect public health or prevent an adverseDRAFT DOCUMENT FOR OMB REVIEW DATED 10/26/2011

environmental effect. EPA has combined the two review activities into the RTR reviews for the Ferroalloys Production source category.

The ferroallo y process involves the reduction smelting of metallic ores (ferrous oxides, silicon oxides, manganese oxides) and a carbon

- source reducing agent, usually in the form of coke, charcoal, high

- and low

- volatility coal, or wood chips. These materials are fed into an electric arc furnace (EAF) a t high temperatures and the carbon source reacts with the metal oxides to form carbon monoxide ( CO ) and the ferromanganese (FeMn) or silicomanganese (SiMn) product

. This process also releases PM and metallic HAP from th e furnace that is either captured by the furnace hood and routed to a particulate control device or is emitted as fugitive emissions. The particulate control device (e.g., fabric filter baghouse, wet venturi scrubber) achieves both reductions in PM and metallic HAP from the exhaust stream . For the fabric filter baghouse, it was estimated that emissions of PM and non

- Hg metallic HAP are reduced by 99 percent. The venturi scrubber is estimated to achieve reductions of 9 5 percent for both PM and non

- Hg

me tallic HAP. The two particulate control devices are estimated to reduce mercury emissions by approximately 15 percent. This is because mercury is believed to be 80 percent elemental mercury, which is not captured by the particulate control device and 20 percent mercuric chloride, which can be captured by the particulate control device.

2.0 Metallic HAP Surrogate
The current NESHAP for ferroalloys production (40 CFR Part 63, subpart XXX) uses PM as a surrogate for metallic HAP by setting a PM standard for both new and existing EAFs. The recent 

### DC Circuit Court opinion in the National Lime II (233 F.3d 625) ha s revised the methodologies used to
determine if c riteria pollutants can be used as a surrogate for HAP. The 

### DC Circuit Court stated that EPA „„may use a surrogate to regulate hazardous pollutants if it is „reasonable‟ to do so‟‟ and laid out criteria establishing a three

- part analysis for determining wh ether the use of PM as a surrogate for non

- Hg metal HAP was reasonable. The DC Circuit Court found that PM is a reasonable surrogate for HAP if: (1) „„HAP metals are invariably present in * * * PM;‟‟ (2) „„PM control technology indiscriminately captures HAP metals along with other particulates;‟‟ and (3) „„PM control is the only means by which facilities „achieve‟ reductions in HAP metal emissions.‟‟ 233 F.3d at 639. If these criteria are satisfied and the PM emission standards reflect what the best sour ces achieve

— complying with CAA section 7412(d)(3)

— „„EPA is under no obligation to achieve a particular numerical reduction in HAP metal emissions.‟‟DRAFT DOCUMENT FOR OMB REVIEW DATED 10/26/2011



### Based on this opinion, the EPA justifies its decision to regulate PM as "a surrogate for nonvolatile HAP m etals" by noting first that PM generated by EAFs invariably contains HAP metals . This was confirmed from the baghouse dust data that was collected for the Information Collection Request (ICR) for ferroalloys production. Based on th ese results , it can be stated that preventing the emission of a unit of PM prevents the emission of some quantum of HAP metals. Using PM as a surrogate thus "achieves exactly the same level of HAP metal emissions limitation" as would be reached were the metals to be regulated di rectly. The EPA also believes that the MACT floor equipment and level of control for non
- Hg HAP metals is identical to that for PM. In addition, the use of a surrogate eliminates the cost of performance testing to comply with numerous standards for indiv idual metals , and also reduces the costs of EPA and state compliance oversight and enforcement efforts



### . Therefore, it was determined that PM would be used as a surrogate for non

- Hg metallic HAP ( arsenic, chromium, chromium VI, lead, manganese, and nickel) and a separate standard would be proposed for mercury emissions from EAFs.