Contract analysis

I. Summary of HEA Comments Before addressing each comment in detail, we provide a brief catalog of the three principal assertions contained in HEA's July 11, 2023, comment letter: Comment 1 — NOx BACT. HEA asserts that the BACT analysis for NOx emissions from the MEF is "inadequate" and that "more stringent controls should be required" for the Facility's natural gas-fired combustion units. HEA contends, in general te

II. Response to HEA Comment on NOx BACT Analysis

II.A. Overview of NOx Emissions and Proposed BACT The MEF's aggregate potential to emit ("PTE") for NOx, calculated across all emission units at maximum design capacity and assuming year-round operation (8,760 hours per year) without voluntary limits, is 312 tons per year ("tpy"). This PTE exceeds the 250 tpy major-source threshold applicable to unnamed source categories under 40 C.F.R. § 52.21(b)(1)(i)(b), thereby t

II.B. RACT/BACT/LAER Clearinghouse Review GAP's BACT analysis for NOx was prepared by Pinnacle in accordance with the EPA's well-established top-down BACT methodology, as described in the New Source Review Workshop Manual (Draft, October 1990) and as required under 40 C.F.R. § 52.21(b)(12). The top-down approach requires the applicant to proceed through five sequential analytical steps: Step 1 — Identify All Availabl

II.C. Comparable Recent PSD Permits In addition to the RBLC review, GAP and Pinnacle identified the following three recent PSD permit determinations by Midwest state agencies for soybean processing and agricultural drying facilities that are directly comparable to the MEF and that established BACT for NOx at emission rates consistent with or less stringent than the 0.036 lb/MMBtu limit proposed by GAP:

1. Illinois EPA, PSD Permit No. 178230096, Decatur Soy Products LLC, Macon County, Illinois (issued March 14, 2022). This permit authorized construction of a 3,500 tpd soybean crush facility with a 100 MMBtu/hr natural gas-fired process heater and a 75 MMBtu/hr natural gas-fired dryer. BACT for NOx was established at 0.04 lb/MMBtu using low-NOx burners with flue gas recirculation. SCR was evaluated and eliminated bas

2. Minnesota Pollution Control Agency, Air Emission Permit No. 04900475-101, Prairie Grain Processors Inc., Blue Earth County, Minnesota (issued August 3, 2021). This permit authorized a 2,800 tpd soybean processing and biodiesel feedstock facility. The primary combustion source was an 85 MMBtu/hr natural gas-fired process heater. BACT for NOx was established at 0.036 lb/MMBtu using low-NOx burners with FGR. The MPCA

3. Indiana Department of Environmental Management, PSD Permit No. T159-42177-00060, Hoosier Agri-Processing LLC, Vigo County, Indiana (issued January 19, 2023). This permit authorized a soybean extraction and meal drying facility with two natural gas-fired dryers rated at 90 MMBtu/hr and 60 MMBtu/hr, respectively. BACT for NOx was established at 0.05 lb/MMBtu using low-NOx burners without FGR. The IDEM permit record

II.D. Conclusion on NOx BACT For the reasons set forth above, the proposed NOx emission limit of 0.036 lb/MMBtu, achieved through the installation and operation of low-NOx burners with flue gas recirculation on EU-01 and EU-02, represents BACT under the top-down methodology prescribed by 40 C.F.R. § 52.21(b)(12). The analysis is thoroughly documented in Section 5.2 of Pinnacle's BACT Analysis Report (Appendix D to th

III. Response to HEA Comment on PM2.5 BACT Analysis

III.A. Overview of PM2.5 Emissions and Proposed BACT The MEF's aggregate potential to emit for PM2.5 (filterable plus condensable) is 87 tpy, and the aggregate PTE for PM10 is 196 tpy. Both values include contributions from combustion sources, material handling and storage operations, and cooling tower drift. The primary sources of particulate emissions at the Facility, as identified in the PSD application, are as fo

III.B. Adequacy of Control Technology Evaluation Pinnacle's top-down BACT analysis for PM2.5 and PM10 evaluated all available particulate matter control technologies for each emission unit category, consistent with the five-step methodology described in Section II.B above. The technologies identified and evaluated for EU-04 (material handling and storage) included: (a) Baghouse/fabric filters (pulse-jet type), achiev

III.C. Air Dispersion Modeling Demonstrates NAAQS Compliance In addition to the BACT analysis, the PSD application includes a comprehensive air quality impact assessment prepared by Pinnacle using the EPA-approved AERMOD dispersion modeling system (Version 23.1, regulatory default mode). The purpose of the modeling analysis is to demonstrate that emissions from the MEF, at the proposed BACT-controlled emission rates,

III.D. Conclusion on PM2.5 BACT For the reasons set forth above, GAP's BACT analysis for PM2.5 and PM10 is thorough, methodologically sound, and consistent with the EPA's top-down BACT methodology. The analysis is supported by a comprehensive RBLC review confirming that the proposed emission limits represent the most stringent control levels achievable for the source categories at the MEF. The ambient air quality imp

IV. Response to HEA Request for a Public Hearing

IV.A. Legal Standard for Public Hearings HEA's third comment requests that IDNR convene a public hearing on the draft PSD Construction Permit. The legal standard governing public hearings on PSD permit applications in Iowa is set forth in Iowa Administrative Code 567—33.3(455B), which provides that the IDNR "may hold a public hearing" on a PSD construction permit application if there is "significant public interest"

IV.B. Public Comment Record Does Not Warrant a Hearing During the thirty-day public notice period (June 12 through July 12, 2023), IDNR received a total of four written comments on the draft PSD Construction Permit. The substance of these comments is summarized as follows:

1. Neighboring Landowner No. 1 (name and address on file with IDNR): This commenter expressed general concerns about the potential for increased dust and particulate matter in the vicinity of the Facility, and asked whether the Facility would generate noticeable odor. The commenter did not raise any specific technical objections to the BACT analysis or permit conditions.

2. Neighboring Landowner No. 2 (name and address on file with IDNR): This commenter similarly expressed concerns about particulate matter and inquired about the hours of operation for truck traffic at the Facility. The commenter did not challenge the adequacy of the permit analysis or request a hearing.

3. Muscatine County Soil & Water Conservation District: This commenter requested clarification regarding stormwater management and erosion control measures at the MEF site during construction. These issues relate primarily to GAP's forthcoming NPDES General Permit No. 2 coverage for stormwater discharges associated with construction activity, and to the Muscatine County grading permit, rather than to the PSD air qual

4. Heartland Environmental Alliance: HEA's comment letter raised the three substantive issues addressed in Sections II, III, and IV of this letter. The total of four comments received during the public notice period does not demonstrate the degree of public interest that would warrant a formal public hearing. Two of the four comments relate to general neighborhood concerns that are addressed through the BACT analysis

IV.C. GAP's Position GAP respectfully submits that the existing public comment record is complete and that the substantive issues raised by HEA and all other commenters can be — and are being — fully resolved through written responses and the IDNR responsiveness summary, without the need for a formal public hearing. A hearing would not meaningfully contribute to the development of the permit record beyond what is alr

V. Additional Contextual Information GAP wishes to provide the following additional contextual information for the benefit of the IDNR's evaluation of the permit record and the comments received: Local Land-Use Approval. GAP has obtained all required local land-use approvals for the construction and operation of the MEF. On November 15, 2022, the Muscatine County Board of Supervisors approved Conditional Use Permit N

VI. Conclusion and Request In summary, GAP believes that the PSD application and supporting technical analyses — including the comprehensive emissions inventory, the top-down BACT analyses for all regulated pollutants, and the AERMOD air dispersion modeling performed by Pinnacle Environmental Consultants Inc. — demonstrate full compliance with all applicable PSD requirements under the Clean Air Act, 40 C.F.R. § 52.21