On August 30, 2013, Ohio EPA released revised guidance concerning applying Best Available Technology (BAT) for sources that emit greater than 10 tons per year (tpy). This guidance is applicable when BAT must be determined for new or modified sources included in permits issued on or after October 1, 2013. The revised memo supersedes the BAT Requirements for Permit Applications Filed on or After August 3, 2009 memo dated December 10, 2009. While the memo revises/clarifies the four (4) step process from the 2009 memo it primarily addresses case-by-case BAT determinations. Case-by-case BAT consists of the following four (4) options:

  1. Work Practices
  2. Source Design Characteristic or Design Efficiency of Control Device
    • Low-NOX burner achieving 0.1 lb NOX/MMBtu heat input
    • Incinerator meeting 95% control of VOC
    • No ongoing limits!
  3. Raw Material Throughput Limitations
    • e.g., 45.6 tons steel produced per rolling, 12-month period
    • No short term limits
  4. Monthly Allowable Emissions
    • e.g., 3.21 tons VOC per month averaged over a twelve-month rolling period

The 2009 guidance provided that Work Practice BAT would typically be represented in an opacity limit. The revised guidance allows for BAT that sets periodic control frequency instead of opacity requirements (e.g., particulate from roadways controlled by water spray at specified frequency). The permittee can still choose to include an opacity limit if it is preferred.

Under the 2009 guidance, sources that fell under the Source Design Characteristic or Design Efficiency of Control Device option, the BAT limit was represented in short term emission limits with specified units (e.g., lb/hr, lb/ton, ppm, etc.) based on source type. The revised guidance limits the use of short term emission limits to only those cases where the air pollution source or control device was specifically designed to meet a certain emission rate for a specific pollutant. For equipment not designed to meet certain short-term limits, annual type limits will be established.

The revised memo provides that since sources that use the Source Design Characteristic or Design Efficiency of Control Device approach for BAT have no ongoing compliance obligations, this BAT cannot be used to limit PTE. Therefore, these sources may need to voluntarily take a federally enforceable limit in order to avoid PSD and Title V permitting requirements. However, ongoing conversations with Ohio EPA have indicated that this may not be the case for PSD avoidance, and the agency intends to provide further guidance on the topic.

Click here to view the revised memo. Please contact Ms. Ellen Hewitt at 614-433-0733 if you have any questions about this article.