South32 Hermosa Inc motion to intervene_packet.pdf

24A-A01-DEQ · Department of Environmental Quality · 2024-10-30

Eric L. Hiser (013023) Trevor J.L. Burggraff (027495) HISER JOY, P.L.C. 5080 N. 40th Street, Unit 245 Phoenix, AZ 85018 Telephone: (480) 505-3900 Facsimile: (480) 505-3901 [email redacted] [email redacted] Attorneys for Proposed Respondent-Intervenor South32 Hermosa Inc.

IN THE OFFICE OF ADMINISTRATIVE HEARINGS In The Matter Of: ADEQ Docket No. 24A-A01-DEQ CLASS I PERMIT NO. 96653 MOTION TO INTERVENE THE HERMOSA PROJECT BY SOUTH32 HERMOSA INC. (Assigned to the Honorable [Judges Sam Fox) Pursuant to Arizona Administrative Code Section R2-19-102(C) and Arizona Rule of Civil Procedure 24, South32 Hermosa Inc. (“South32”) timely moves to intervene in this challenge by petitioner Chris Werkhoven to an air permitting decision by the Arizona Department of Environmental Quality (“ADEQ”). South32 is the holder of the challenged permit, which authorizes the company to construct and operate the Hermosa project (“Project”). South32 is authorized to state that ADEQ does not oppose the motion. Mr. Werkhoven thus far has declined to state his position. BACKGROUND AND PROCEDURAL HISTORy The Project is the only advanced U.S. mineral development project capable of producing two federally-designated critical minerals, manganese and zinc. The Project has the potential to strengthen America’s domestic supply chain, contribute to U.S. national security, and reduce U.S. reliance on foreign sources of the resources America needs to power the nation’s clean energy transition. It is the only mineral development project approved for inclusion in the federal government's FAST-41 permitting process,

created to reduce delays in federal environmental review of nationally important

infrastructure projects.

ARGUMENT

South32 is entitled to intervention as of right or, alternatively, permissive

intervention. The Arzona Rules of Civil Procedure provide guidance here, where the Office of Administrative Hearings has no separate procedure. See ARIZ. ADMIN. CODE § R2-19-102(C) (“[i]f a procedure is not provided by statute or these rules, an administrative law judge may issue an order using the Arizona Rules of Civil Procedure and related local rules for guidance.”) Rule 24(a)(2) provides for intervention as of right to a party that “claims an interest relating to the subject of the action, and is so situated that disposing of the action in the person’s absence may as a practical matter impair or impede the person’s ability to protect that interest, unless existing parties adequately represent that interest.” In making this determination, Arizona courts have held that this rule is to be interpreted expansively, so as to assure that a party’s due process rights are preserved. Rule 24 “is remedial and should be liberally construed with the view of assisting parties in obtaining justice and protecting their rights.” Bechtel v. Rose, 722 P.2d 236, 240 (Ariz. 1986) (quoting Mitchell v. City of Nogales, 320 P.2d 955, 958 (Ariz. 1958)). South32’s interests may be substantially affected in this case. South32 was granted the permit being challenged by the appellant; holds the rights to the property where the Project will be constructed and operated; and has invested substantial amounts of capital and resources in the Project. South32 will be significantly harmed without opportunity to support its own interests if it is not allowed to be a party to these proceedings. South32 clearly has a protectable interest in these proceedings sufficient to satisfy Rule 24. South32 has already been granted the permit at issue. Any objections or changes to the permit, assuredly resulting in delay or further revisions, would directly impact South32. South32 has commenced construction of the Project and has invested significant resources and financial commitment. A judgment against South32’s permit would have a direct and harmful, if not irreparable, economic harm on South32 (including significant economic injury to the regional and local community). Without intervention, South32 cannot practically protect its interests since any decision in this case will directly affect South32. Moreover, the OAH has allowed intervention in similar cases. See Save the Scenic Santa Ritas v. Cabrera, No. 1 CA-CV 15-0226, 2016 WL 3773516 (Ariz. Ct. App. July 12, 2016); see also Rosemont Copper Co. Mot. to Intervene, Mar. 29, 2013. South32’s interests may, as a practical matter, be impaired if intervention is denied. Further, South32’s interests may not be adequately represented by the existing parties. ARIZ. R. CIV. PRO. 24(a)(2). Mr. Werkhoven, of course, challenges the permit. The only other party, ADEQ, serves a different role than South32. As a regulatory agency, ADEQ’s interests in the management of its regulatory permit program do not necessarily align with the interests of South32 as to this single permit. Additionally, South32 and

ADEQ may also have differing views as to legal strategy.

Finally, South32’s motion to intervene is timely, and the company’s intervention

will not unduly delay or prejudice the adjudication of the original parties’ rights. A

written motion need only be filed with the OAH at least fifteen days before the scheduled

hearing. ARIZ. ADMIN. CODE § R2-19-106(C). No merits hearing has been scheduled and nothing of substance has occurred. ADEQ filed its response to Mr. Werkhoven’s appeal on October 21, 2024. South32 also qualifies for permissive intervention under Rule 24 (b), as it shares an interest in the common question of the legality of its permit, for the reasons discussed above. For the foregoing reasons, South32 respectfully requests that it be granted leave to intervene. South32’s proposed responsive pleading is attached. RESPECTFULLY SUBMITTED this 30th day of October, 2024. By: s/ Eric L. Hiser HISER JOY Eric L. Hiser #013023 Trevor J.L. Burggraff # 5080 N. 40th Street, Unit 245 Phoenix, AZ 85018 [email redacted] [email redacted] 480-505-3900 PERKINS COIE LLP Christopher D. Thomas #010482 2525 E. Camelback Rd., Suite 500 Phoenix, Arizona 85016-4227 [email redacted]

SOUTH32 HERMOSA INC. Todd Gwillim #036439 1860 East River Road, Suite 200 Tucson, Arizona 85718 [email redacted] Attorneys for South32 Hermosa Inc. CERTIFICATE OF SERVICE I hereby certify that on October 30, 2024, I filed the foregoing Motion to Intervene via the Office of Administrative Hearing’s electronic submission system. /s Eric L. Hiser Copies were served personally and by electronic mail on: Kristin K. Mayes #14000 Paul A. Phelps #037355 Assistant Attorney General Environmental Enforcement Section Office of the Attorney General 2005 N Central Ave Phoenix, AZ 85004 [email redacted] Attorneys for the Arizona Department of Environmental Quality Chris Werkhoven PO Box 0590 Sonoita, AZ 85637 [email redacted] Eric L. Hiser (013023) Trevor J.L. Burggraff (027495) HISER JOY, P.L.C. 5080 N. 40th Street, Unit 245 Phoenix, AZ 85018 Telephone: (480) 505-3900 Facsimile: (480) 505-3901 [email redacted] [email redacted] Attorneys for Respondent-Intervenor South32 Hermosa Inc. IN THE OFFICE OF ADMINISTRATIVE HEARINGS In The Matter Of: Docket No. 24A-A01-DEQ

ADEQ SOUTH32 HERMOSA INC.’S

CLASS I PERMIT NO. 96653 RESPONSE TO NOTICE OF APPEAL

THE HERMOSA PROJECT (Assigned to the Honorable Sam Fox)

IN THE OFFICE OF ADMINISTRATION HEARINGS Respondent-Intervenor South32 Hermosa Inc. (South32) presents the following defenses to Chris Werkhoven’s Notice of Appeal in support of its Motion to Intervene and admits, denies and alleges as follows: INTRODUCTORY STATEMENTS 1. South32 is a Nevada corporation authorized to do business in Arizona.

2. South32 is the owner and operator of the Hermosa Project, a zinc-manganese mine to be developed south of Patagonia in Santa Cruz County, Arizona. Because of the economic and national security significance of the Hermosa Project, in May 2023, the Federal Permitting Improvement Steering Council added the Project to the FAST-41 “critical infrastructure projects” list. 3. On October 21, 2022, South32 applied to the Arizona Department of Environmental Quality (ADEQ) for a Class I air quality permit for the Hermosa Project. The October 21, 2022, application was supplemented at various times, and a final consolidated application including all updates and revisions requested by ADEQ was submitted in December 2023. 4. Based on South32’s final consolidated application, on June 10, 2024, ADEQ issued a proposed final permit to South32 authorizing construction of the Hermosa Project. As the permittee and owner/operator of the Hermosa Project, South32 is a real party in interest in this proceeding. 5. On August 26, 2024, after addressing and resolving comments on the proposed final permit by the U.S. Environmental Protection Agency (EPA), ADEQ issued a final permit to South32 authorizing construction of the Hermosa Project. ANSWERS TO PETITIONER’S STATEMENTS1 6. In response to the allegations in paragraph A.1, South32 admits that appellant submitted comments on February 26, 2024, on the draft Air Quality Control Permit No. 96653 issued on or around January 25, 2024, but denies that such comments provide any basis for relief herein 7. In response to the allegations in paragraph A.2, South32 admits that ADEQ’s Responsiveness Summary to Public Comments (RSPC) and the proposed final permit (PFP) were issued on June 10, 2024, but denies for want of knowledge 1 Petitioner Werkhoven’s Notice of Appeal is not numbered. South32 has added numbers to the Notice of Appeal to assist in reference. A copy of the numbered Notice of Appeal is attached. whether appellant’s comments were implemented, ignored or dismissed by ADEQ. 8. South32 denies for want of knowledge the allegations in paragraph A.3. 9. South32 denies for want of knowledge the allegations in paragraph A.4. 10. In response to the allegations in paragraph A.5, South32 admits that appellant filed a Notice of Appeal (NoA) on or about July 8, 2024, the terms of which speak for themselves. South32 denies that the NoA provides any basis for relief herein. 11. South32 denies for want of knowledge the allegations in paragraph A.6.

12. South32 denies for want of knowledge the allegations in paragraph A.7. 13. In response to the allegations in paragraph A.8, South32 admits that ADEQ issued the final permit authorizing construction and operation of the South32 Hermosa Mine on August 26, 2024. 14. South32 denies for want of knowledge the allegations in A.9. 15. South32 denies for want of knowledge the allegations in paragraph A.10.

16. South32 denies for want of knowledge the allegations paragraph A.11. 17. In response to the allegations in paragraph A.12, South32 admits that appellant is filing an appeal. South32 denies that relief is warranted. 18. In response to the allegations in paragraph B.1, South32 admits that EPA- approved dispersion modeling programs may be used to demonstrate compliance with national ambient air quality standards (NAAQS). South32 denies for want of knowledge the remaining allegations in this paragraph. 19. In response to the allegations in paragraph B.2, South32 admits that “site- specific” emission rate determinations are not required for air quality models and denies that the emission factors used herein were not protective. South32 denies the remaining allegations in this paragraph. 20. In response to the allegations in paragraph B.3, South32 states that appellant’s beliefs are irrelevant to the appeal of ADEQ’s issuance of South32’s final permit. South32 further denies for want of knowledge the allegations in this paragraph. 21. In response to the allegations in paragraph B.4, South32 admits that lead is regulated by primary and secondary NAAQS. South32 denies that lead is the only metal regulated under the NAAQS because metals in particulate form are regulated as part of particulate by the particulate NAAQS. South32 denies for want of knowledge the other allegations in this paragraph. 22. Paragraph B.5 is a statement of opinion that requires no response. To the extent a response is required, South32 denies the allegations in this paragraph. 23. In response to the allegations in paragraph B.6, South32 admits that EPA has authorized AP-42 and that it is frequently used in air permitting. South32 denies that it would necessarily improve protection of public health to abandon use of AP-42 to supply emissions factors used for air permitting purposes. South32 denies the implication that the data used from AP-42 is of lower reliability. South32 asserts that it used site-specific data in its permit application as available and appropriate. South32 denies the remaining allegations in this paragraph. 24. Paragraph B.7 is a statement of opinion that requires no response. To the extent a response is required, South32 denies the allegations in this paragraph. 25. In response to the allegations in paragraph B.8, South32 admits that the U.S.

Geological Survey (USGS) conducted a study on the Patagonia mountains, the

terms of which speak for themselves. South32 denies for want of knowledge

the remaining allegations in this paragraph.

26. In response to the allegations in paragraph B.9, South32 denies that the referenced study is relevant to the Hermosa Project and denies the remaining allegations in said paragraph. 27. In response to the allegations in paragraph B.10, South32 admits deposition of airborne particles will occur, albeit only at levels protective of public health and the environment. South32 denies the implication that the emissions estimates for metals were not provided to ADEQ as part of South32’s complete permit application. South32 denies that ambient concentrations of such metals resulting from its operations create a public health or environmental threat. South32 denies the remaining allegations in this paragraph. 28. South32 denies the allegations in issue 1, paragraph 1 (Silt Percentage of On- site Haul Roads). South32 further denies that Mr. Werkhoven may appeal on this issue, since he failed to raise it during public comment, as required by A.R.S. 41-1092.03(B). South32 denies that the silt percent is “incorrect, non- conservative” value. South32 denies that a margin of safety is required given that the NAAQS are set at a level to provide an adequate margin of safety. 29. In response to the allegations in issue 1, paragraph 2 (Silt Percentage of On-site Haul Roads), South32 admits that haul road traffic on unpaved roads is the largest source of fugitive dust at the Hermosa Project. South32 denies for want of knowledge the allegation that ADEQ ignored this issue is the RSPC. South32 denies the remaining allegations in this paragraph. South32 further denies that Mr. Werkhoven may appeal on this issue, because he failed to raise it during public comment, as required by A.R.S. 41-1092.03(B). 30. In response to the allegations in issue 1, paragraph 3 (Silt Percentage of On-site Haul Roads), South32 admits that the company provided in its application one silt percentage value to calculate emission rates for roads listed as “Underground Taylor Roads” and “Underground Clark Roads,” which percentage was chosen based on best engineering judgement of South32. South32 denies the remaining allegations in this paragraph. 31. In response to the allegations in issue 1, paragraph 4 (Silt Percentage of On-site Haul Roads), South32 admits that the 5.1% value used in AP-42 for Western Surface Coal Mining was one of the sources of data for fugitive dust sources. South32 denies the implication that ADEQ abandoned being “conservative” in estimating emissions by allowing the use of the 5.1% silt factor from AP-42. South32 denies the remaining allegations in this paragraph. South32 further denies that Mr. Werkhoven may appeal on this issue, because he failed to raise it during public comment, as required by A.R.S. 41-1092.03(B). 32. In response to the allegations in issue 1, paragraph 5 (Silt Percentage of On-site Haul Roads), South32 admits that the company used the 5.1% value for the silt content calculations “Underground Taylor Roads” and “Underground Clark Roads.” South32 admits that the application emissions spreadsheets refer to a conversation on October 14, 2022, that ADEQ had with AMI (now known as South32 Hermosa Inc.) about the justification for the silt content number. South32 denies that the 5.1% is not justified. South32 denies the remaining allegations in this paragraph. South32 further denies that Mr. Werkhoven may appeal on this issue, since he failed to raise it during public comment, as required by A.R.S. 41-1092.03(B). 33. In response to the allegations in issue 1, paragraph 6 (Silt Percentage of On-site Haul Roads), South32 admits that the silt percentage is proportional to the silt content based on the equation used to determine the emission rate from road traffic. South32 asserts that silt is, however, not the only parameter that affects emission rate. South32 admits that the outcomes of the modeled concentration of particles in the NAAQS Impact Analysis did not change between the draft permit, proposed final permit and final permit. South32 denies the remaining allegations in this paragraph. South32 further denies that Mr. Werkhoven may appeal on this issue, since he failed to raise it during public comment, as required by A.R.S. 41-1092.03(B). 34. In response to the allegations in issue 1, paragraph 7 (Silt Percentage of On-site Haul Roads), South32 denies for want of knowledge whether the information in issue 1, paragraph 6 above was the reason that the ADEQ response on June 18, 2024, stated that “the application was not updated.” South32 denies the remaining allegations in this paragraph. South32 further denies that Mr. Werkhoven may appeal on this issue, since he failed to raise it during public comment, as required by A.R.S. 41-1092.03(B). 35. In response to the allegations in issue 1, paragraph 8 (Silt Percentage of On-site Haul Roads), South32 admits that ADEQ did state in the Response to Comments that as South32 is a new facility that has not been built yet, “obtaining site-specific data isn’t feasible, and thus, the cited data sources are considered the most representative of the proposed units and standard air quality engineering practices.” South32 admits it submitted Significant Amendment to APP No. P-512235 but denies there were 27 sampling points. South32 asserts there are 35 sampling locations. South32 denies that these sampling results are relevant to the air permit action. South32 denies the remaining allegations in this paragraph. South32 further denies that Mr. Werkhoven may appeal on this issue, since he failed to raise it during public comment, as required by A.R.S. 41-1092.03(B). 36. In response to the allegations in issue 1, paragraph 9 (Silt Percentage of On-site Haul Roads) denies that it did not use the most accurate available silt percentages as an input in the equation to calculate particle emissions for the referenced roads. South32 asserts that the silt percentages provided in the Significant Amendment to the APP permit were located near riverbeds and other areas where water is sometimes present and therefore the silt percentages are higher in these areas than the roads. South32 denies the remaining allegations in this paragraph. South32 further denies that Mr. Werkhoven may appeal on this issue, since he failed to raise it during public comment, as required by A.R.S. 41-1092.03(B). 37. In response to the allegations issue 1, paragraph 10 (Silt Percentage of On-site Haul Roads), South32 agrees that it has been performing preconstruction activities at the site (e.g. building access tunnels and shafts) but denies that these preconstruction activities would provide “best available” model input data for post-construction operations. South32 denies the remaining allegations in this paragraph. South32 further denies that Mr. Werkhoven may appeal on this issue, since he failed to raise it during public comment, as required by A.R.S. 41-1092.03(B). 38. In response to the allegations issue 1, paragraph 11 (Silt Percentage of On-site Haul Roads), South32 admits that the annual PM2.5 emissions using “potential to emit” values from the project are near the level of the current PM2.5 NAAQS. South32 denies the implication that the project will exceed the PM2.5 NAAQS, as actual emissions at the mine site will be much lower than the “potential to emit” estimates used for estimating emissions as required by permitting rules promulgated under the Clean Air Act. South32 denies the remaining allegations in this paragraph. South32 further denies that Mr. Werkhoven may appeal on this issue, since he failed to raise it during public comment, as required by A.R.S. 41-1092.03(B). 39. In response to the allegations in issue 2, paragraph 1 (Metal Fractions on Haul Road Soils), South32 denies that ADEQ failed to disclose the metal fractions used in the dispersion model for particles emissions by underground road traffic. This information appeared in both the application provided by South32 and any supplements to the application. South32 denies the remaining allegations in this paragraph. 40. In response to the allegations in issue 2, paragraph 2 (Metal Fractions on Haul Road Soils), South32 admits that the subject of metal fractions in road soils was discussed in ADEQ’s Response to Comments. South32 denies the remaining allegations in this paragraph. 41. In response to the allegations in issue 2, paragraph 3 (Metal Fractions on Haul Road Soils), South32 admits that road emissions are a source of particulate matter emissions. South32 denies the implication that the company and ADEQ did not use the “best available” information to estimate the emissions rates of particulate matter and the metal fraction for particulate matter sources. South32 denies the remaining allegations in this paragraph. 42. In response to the allegations in issue 2, paragraph 4 (Metal Fractions on Haul Road Soils), South32 admits that ADEQ initially used a 1991 ADEQ publication. As set forth below, South32 denies that the final permit relied upon the 1991 data for lead or manganese. South32 denies for want of knowledge the remaining allegations of this paragraph. 43. In response to the allegations in issue 2, paragraph 5 (Metal Fractions on Haul Road Soils), South32 admits that ADEQ states “[t]his report was not previously known to ADEQ during the review and processing of the South32 permit application.;” South32 denies the implication that best information was not used because South32 recalculated results after Petitioner’s comment was received to evaluate whether using the USGS data resulted in a meaningful change to the results presented, and it did not. South32 denies the remaining allegations in this paragraph. 44. In response to the allegations in issue 2, paragraph 6 (Metal Fractions on Haul Road Soils), South32 admits that the information from the USGS 2019/2020 report was used to recalculate potential to emit. South32 denies the implication that recalculating the emissions proves that the best information and data was not used to estimate emissions. South32 denies that the “most conservative” data is an appropriate metric given the data under consideration. South32 denies the remaining allegations in this paragraph. 45. In response to the allegations in issue 2, paragraph 7 (Metal Fractions on Haul Road Soils), South32 states that metal fractions were provided in the application. South32 updated the emissions estimates for the aboveground roads based on the USGS 2019/2020 report in a letter to ADEQ in May 2024 in response to public comments that showed the update did not affect the public health and environment conclusions. Based on this information, ADEQ revised its Technical Support Document (TSD) and proposed final permit, both of which were available to the public. South32 denies the remaining allegations in this paragraph. 46. In response to the allegations in issue 2, paragraph 8 (Metal Fractions on Haul Road Soils), South32 denies that underground metal emissions were underestimated. South32 used site-specific data to determine particulate/metals emissions from underground roads. South32 denies the remaining allegations in this paragraph. 47. South32 admits the allegation in issue 2, paragraph 9 (Metal Fractions on Haul Road Soils), but denies that it provides any basis for relief herein. 48. In response to the allegations in issue 2, paragraph 10 (Metal Fractions on Haul Road Soils), South32 admits that it used rock and its metal values for the underground roads and that these values are in its application and did not require change. South32 further admits that the spreadsheets in its application were not updated to re-estimate or re-evaluate metal fraction values for aboveground roads: this information was provided to ADEQ by letter and email. South32 affirmatively states that its handling of metals in underground roads is in its application. South32’s letter to ADEQ evaluating the 2020 USGS report is in the administrative record. South32 lacks sufficient knowledge to admit or deny what the difference between “re-estimation” and “re-evaluation” is in ADEQ’s Response to Comments document. South32 denies the remaining allegations in this paragraph. 49. In response to the allegations in issue 2, paragraph 11 (Metal Fractions on Haul Road Soils), South32 admits that ADEQ’s Response to Comments states that “these changes do not change any applicable requirements or adversely impact any modeling outcomes.” South32 denies any implication that ADEQ did not do its job properly because the revised information did not lead to a change in applicable requirements or modeling outcomes. South32 denies the remaining allegations in this paragraph. 50. South32 denies the allegations in issue 3, paragraph 1 (Deposition and Accumulation of Particles). To the extent any allegations are relevant to an air proceeding, the secondary particulate NAAQS covers welfare effects such as those alleged. 51. In response to the allegations in issue 3, paragraph 2 (Deposition and Accumulation of Particles), South32 denies that there are legally demonstrated and catalogued impairments from South32 or its predecessor. South32 denies the remaining allegations in this paragraph. 52. In response to the allegations in issue 3, paragraph 3 (Deposition and Accumulation of Particles), South32 admits that in the dispersion modeling for particulate matter, the particle size is an important parameter for estimating particle deposition or settling. South32 admits that the secondary NAAQS protect “public welfare” and the primary NAAQS protect “public health” and the Project complies with both sets of NAAQS. South32 denies the remaining allegations in this paragraph. 53. In response to the allegations in issue 3, paragraph 4 (Deposition and

Accumulation of Particles), South32 admits that ADEQ’s Response to Comment states that the secondary NAAQS standard for lead is the same as the primary standard. South32 further admits the final permit will be protective of the public welfare, including preservation of soil and water. South32 denies the remaining allegations in this paragraph. 54. In response to the allegations in issue 3, paragraph 5 (Deposition and Accumulation of Particles), South32 admits that ADEQ’s statement is properly quoted. South32 denies for want of knowledge the remaining allegations in this paragraph. 55. In response to the allegations in issue 3, paragraph 6 (Deposition and Accumulation of Particles), South32 denies the implication that emissions were underestimated from sources of fugitive dust and further denies the remaining allegations in this paragraph. 56. In response to the allegations in issue 3, paragraph 7 (Deposition and Accumulation of Particles), South32 denies that the Hermosa Project will cause or contribute to an exceedance of any air quality standard. South32 asserts that the dispersion modeling provided to ADEQ as part of the required permitting process shows that it will not cause or contribute to an exceedance of an air quality standard. South32 denies the remaining allegations in this paragraph. 57. In response to the allegations in issue 3, paragraph 8 (Deposition and Accumulation of Particles), South32 denies that sites outside the Ambient Air Boundary of the Hermosa Project have or will have water and/or soil impairments as a result of Hermosa project operations. South32 further denies that the Hermosa Project will cause or contribute to an exceedance of any applicable standard, which is shown by the modeling analysis provided to ADEQ as part of the permitting process. South32 denies the remaining allegations in this paragraph. 58. In response to the allegations in issue 4, paragraph 1 (Emissions from Transported Ore and Concentrate Cargo), South32 denies that on-site cargo emissions from ore and concentrate haul trucks were excluded from the dispersion modeling analysis. South32 further denies that off-site ore-transport is required (or allowed) to be considered. South32 denies the remaining allegations in this paragraph. 59. In response to the allegations in issue 4, paragraph 2 (Emissions from Transported Ore and Concentrate Cargo), South32 admits that ADEQ’s Response to Comments states that for off-site hauling, sealed containers will be used and states that those containers are “closed to the atmosphere” and “maintain integrity in the event of a transportation incident” and that “Utilizing sealed containers will eliminate dust emissions from transported materials.” South32 denies that the issue of how important cargo emissions from transportation trucks has been unanswered and denies the implication that its use of sealed containers is not a best practice. South32 denies the remaining allegations in this paragraph. 60. In response to the allegations in issue 5, paragraph 1 (Traversing Roads), South32 denies that dispersion modeling has not shown compliance with the NAAQS in relation to where Harshaw Road traverses the Hermosa Mine site. South32 asserts that it included Harshaw Road as ambient air as required by the current edition of the Air Quality Modeling Guidelines for Arizona (ADEQ, Nov. 1, 2019). South32 denies the remaining allegations in this paragraph. 61. In response to the allegations in issue 5, paragraph 2 (Traversing Roads), South32 admits that it modeled Harshaw Road as “ambient air” consistent with ADEQ’s 2019 “Air Quality Modeling Guidelines for Arizona Air Quality Permits” (hereinafter “Guidelines”). South32 further states that segments of Harshaw Road located off-site were also classified as "ambient air," and their concentrations were modeled accordingly to ensure compliance with NAAQS.” South32 denies the remaining allegations in this paragraph. 62. In response to the allegations in issue 5, paragraph 3 (Traversing Roads), South32 admits that ADEQ’s 2019 “Air Quality Modeling Guidelines for Arizona Air Quality Permits” (hereinafter “Guidelines”) states that “the ambient air boundary must fully and continuous preclude public access.” South32 further states that, consistent with the Guidelines, South32 modeled Harshaw Road where it passes through the Hermosa Critical Minerals Project as “ambient air.” South32 denies that Harshaw Road requires the Hermosa

Critical Minerals Project to be treated as two nearby sources. South32 denies

the remaining allegations in this paragraph.

AFFIRMATIVE DEFENSES 63. Petitioner’s claims are barred by A.R.S. 41-1092.03(B) to the extent they are based on issues he failed to raise during public comment 64. Petitioner’s Notice of Appeal fails to state a claim upon which relief may be granted. 65. Respondent-intervenor reserves the right to amend this Response at a later time to assert any matter constituting an avoidance or affirmative defense including, without limitation, those affirmative defenses set forth in Rule 8(d), Arizona Rules of Civil Procedure, as shown to be applicable. REQUESTS TO THE OFFICE OF ADMINISTRATIVE HEARINGS WHEREFORE, having fully responded, Respondent-Intervenor requests that Petitioner’s Petition be dismissed, that Petitioner take nothing, and that Respondent’s permit be affirmed. … RESPECTFULLY SUBMITTED this 30th day of October, 2024. By: s/ Eric L. Hiser HISER JOY Eric L. Hiser #013023 Trevor J.L. Burggraff #027495 5080 N. 40th Street, Unit 245 Phoenix, AZ 85018 [email redacted] 480-505-3900

PERKINS COIE LLP Christopher D. Thomas #010482 2525 E. Camelback Rd., Suite 500 Phoenix, Arizona 85016-4227 [email redacted] SOUTH32 HERMOSA INC. Todd Gwillim #036439 1860 East River Road, Suite 200 Tucson, Arizona 85718 [email redacted] Attorneys for South32 Hermosa Inc. CERTIFICATE OF SERVICE I hereby certify that on October 30, 2024, I filed the foregoing Motion to Intervene via the Office of Administrative Hearing’s electronic submission system. /s Eric L. Hiser Copies were served personally and by electronic mail on: Kristin K. Mayes #14000 Paul A. Phelps #037355 Assistant Attorney General Environmental Enforcement Section Office of the Attorney General 2005 N Central Ave Phoenix, AZ 85004 [email redacted] Attorneys for the Arizona Department of Environmental Quality Chris Werkhoven PO Box 0590 Sonoita, AZ 85637 [email redacted] Petitioner (pro se) NOTICE OF APPEAL

By Email Only

To: Hearing Administrator Office of Administrative Counsel Arizona Department of Environmental Quality 1110 W. Washington Street Phoenix, AZ 85007 Email: [email redacted] Ph: 602-771-2212

From: Chris Werkhoven PO Box 0590 Sonoita, AZ 85637 Email: [email redacted] Ph: 602-684-7975

Dated: September 24, 2024

Re: Notice of Appeal on the Arizona Department of Environmental Quality Final Air Quality Control Permit No.96635 for the South32 Hermosa Mine in Santa Cruz County, Arizona

Dear Ms. Murrieta,

1-Thank you for processing this Notice of Appeal (NOA) concerning the Final Air Quality Control Permit No. 96635 (FP) of the Arizona Department of Environmental Quality (ADEQ) that authorizes South32 (S32) to construct and operate its Hermosa Mine for the extraction of metals from the Patagonia Mountains located near the town of Patagonia, Santa Cruz County, Arizona.

2-Chapter A reviews the events preceding this appeal.

3-Chapter B appellant reviews the issues concerning ADEQ responses received pertaining appellant’s comments (Comments) on the issuing of a draft permit (DP) by ADEQ.

4-In Chapter C the requested relief is presented.

A. CHRONOLOGY

1- On February 26, 2024, appellant submitted comments on ADEQ’s Draft Air Quality Control Permit No. 96653 issued on or around January 5, 2024.

2- On June 10, 2024, ADEQ issued its Responsiveness Summary to Public Comments (RSPC) showing that one of appellant’s comments was implemented, all other comments were either ignored or dismissed. A Proposed Final Permit (PFP) was issued on the same day, authorizing “construction” of the Hermosa Mine.

3- On June 18, 2024, upon requesting missing clarifications on how the draft application spreadsheets (DAS) were changed to support the compliance claims in the PFP, ADEQ responded by email that the DAS were not “updated”.

- On July 5, 2024, ADEQ added by email that no further informal exchanges pursued by appellant would be appropriate because appellant confirmed the intention to file an appeal on the PFP. By this response insight in how the PFP claims were underpinned, never surfaced.

5- On July 8, 2024, appellant filed a Notice of Appeal on the PFP, hereinafter called NOA/PFP, arguing some of the Comments were implemented in a non-transparent - and inconsistent manner, dismissed on erroneous grounds or ignored altogether.

6- On July 26, 2024, appellant was notified by ADEQ via email that “no statutory grounds exist” to process the July 8, 2024, appeal and that “ADEQ will not be submitting a request for hearing”. ADEQ stated that none of these arguments concern issues about the legality or reasonableness of ADEQ’s decision to authorize new construction at the Hermosa Project”. By concluding that appellant’s issues apply to operations only, ADEQ decided that “Appeals concerning the operation of a source are not ripe and cannot be submitted until ADEQ issues the Final Permit”.

7- On August 26, 2024, appellant submitted an appeal for a hearing on the July 26 letter to have ADEQ clarify the decisions made in the July 26 letter as appellant concluded that the distinction between “construction” and “operation” appears ambiguous when it comes to the common objective of meeting NAAQS standards.

8- On August 26, 2024, ADEQ issued the FP authorizing construction and operation of the S32 Hermosa Mine.

9- In an accompanying Letter to Commenters (LTC), ADEQ lists the changes made to the PFP. Clearly, none of the issues submitted by appellant in the NOA/PFP were included.

-On August 29, 2024, in a phone call with ADEQ’s Hearing Administrator, appellant agreed with a proposed withdrawal of appellants’ August 26 request for a hearing on the NOA/PFP with an added and agreed upon condition that none of the issues raised in the NOA/PFP, are abandoned or waived and can serve in any future appeal.

-On September 23, 2024, appellant was notified by an email from ADEQ’s Office of Administrative Counsel that the ADEQ’s decisions as mentioned in its letter to appellant of July 26, 2024, are rescinded and appellant’s issues as filed in the NOA/PFP do challenge the authorization of new construction and can be used in a NOA for the FP, should appellant choose to do so.

12- On this date, appellant is filing a NOA for the FP that raises the central issue of pollutant emission assessment with a subsequent NAAQS compliance determination, and requests corresponding relief actions.

B. EMISSION ASSESSMENT ISSUES

Preface on Site-Specific Factors

1- In ADEQ air permit applications, only EPA approved dispersion modeling programs are allowed to “demonstrate” that dispersed pollutant concentrations, do comply with the regulated NAAQS air concentrations. Such models have shown remarkable predictability in the past but are, of course, only as reliable as their input parameters are and the judgment about those inputs and corresponding model outcomes on compliance is in the hands of the technical staff of ADEQ and ultimately by state appointed decisionmakers. Appeals like this fortunately offer the possibility that the public can provide a second opinion that may ultimately be tested in court.

2- As inputs to the model, “site-specific” emission rate determinations are recommended by EPA, but are not required. In other words, field testing or field assessments, clearly required in other industries where public health is at risk, is not mandatory, which is a remarkable exception considering that air pollution unavoidably exposes everybody in a short period of time.

3- Corrective actions that follow mistakes due to inaccurate assessment, is costing taxpayers billions of dollars in morbidity expenses and is causing unacceptable levels of premature deaths. A well-known example is the addition of lead (Pb) to gasoline more than 50 years ago that till today is leading to “cradle-to-grave” health monitoring and regularly updated safe standards for Pb in our eco-system.

4- Metal mining and smelting continues to add about the largest amount of waste to air and land justifying pro-active regulations and serious public reviews of any permit applied for and calls for funding of health studies that can update standards. So far, however, Pb is the only metal regulated in the Clean Air Act that has primary - and secondary standards under NAAQS but in 2019 investigations on manganese (Mn) were suspended by Congress.

5- Considering the suite of metal ores S32 is planning to extract next to what is regulated and can be enforced, it is worth focusing the emission assessment issues on particles, in particular Pb-containing particles.

6- Among actions that can be undertaken to improve protection of public health is not to recommend the use of “site-specific” particle emission information, but to require it and abandon the usual data picking from EPA’s AP-42 emission factor handbook or from data provided by suppliers of mining equipment that may or may not be reliable. The only “penalty” of not obtaining and using on-site input data is a lower reliability rating as described in the AP-42 handbook. This rating is not reported in any permit application and thus also not reviewed anywhere in a final judgment on the trustworthiness and margin of safety a claimed compliance has been approved on.

7- Next to a mandatory use of site-specific data, there needs to be a review on whether the technology used to obtain such information is “the best available” and can provide an “adequate margin of safety”. Both aspects are highlighted for the issues raised in this chapter

8- Important to realize at this point is that already in 2007, the US Geological Survey (USGS) determined that the Patagonia Mountains represent a mineralized ecosystem where “understanding the metal pathways in the human food chain” allows “to better plan the impacts of chemical toxicity in sediment, water and biota in areas affected by mining or mineralization”.

9- In the past and recently, high concentrations of metal compounds, dissolved or suspended as particles in water and accumulated in soils, have been identified and quantitatively analyzed by USGS and the University of Arizona (UoA). The study convincingly shows the presence of metal mobilization throughout the Patagonia Mountains leading to bio- accumulation in vegetation. Since mobilization by erosion does concentrate metals in soil and sediment of local streambeds, it is not surprising that the mentioned study observed toxicity levels along Sonoita Creek exceeding known standards and increasing at each next confluence with a tributary originating from the Patagonia Mountains that is known to be metal impaired. A unique finding by itself.

10-Since the deposition of airborne particles will add more metals of the same origin and compositional fingerprint, the need to estimate by how much more metal is being accumulated in soils and water during the life of the Hermosa Mine and after closure, is mandatory in order to pro- actively protect public health and environment, a subject addressed in Comments and re-iterated below in this appeal..

Silt Percentage of On-Site Haul Roads

-Issue 1: The Hermosa Mine NAAQS compliance claim for PM2.5 particles is based on incorrect, non-conservative silt percentages in the estimation of particle emission rate values for haul roads while no margin of safety is provided despite a modeling outcome that is unreasonably close to the NAAQS safe limit value. 2- This topic is part of the Comments but markedly ignored in the RSPC notwithstanding that, according to the DAS, particles suspended by haul road traffic on unpaved roads is Hermosa Mine’s largest source of fugitive particles, followed by wind erosion of tailing storage piles.

3- In this category of fugitive particles two sources are distinguished in the DAS, ie aboveground roads, listed as “Road Emissions”, and underground roads, listed as “Underground Taylor Roads” and Underground Clark Roads”.

ADEQ allowed the use of only one, non-site-specific silt percentage value to calculate emission rates for all road types.

4- This value is published by EPA in its AP-42 handbook on emission factors and was assessed more than 20 years ago for “Western Surface Coal Mines and, as recognized in the DAS, valid for (aboveground) “plant roads”. Haul roads, however, show much higher values in the same EPA assessment study while no value for underground haul roads is presented.

ADEQ clearly abandoned the touted adherence to the principle of being always “conservative” in its estimations.

5- Throughout the DAS calculations, only this value, 5.1%, has been used no matter the nature or location of the haul road. As a justification the DAS refers in a footnote to a “conversation” ADEQ had on October 14, 2022, with AMI, the previous owner of the Hermosa Mine. Since S32 acquired the Hermosa Mine years before that date and since no details about the nature of the conversation have been released, it is not clear why the use of a low, general number was justified.

6- The silt percentage parameter is nearly linearly proportional to the emission rate for PM2.5 particles and thus a sensitive input when it comes to the trustworthiness of particle concentration modeling outcomes for all on-site road traffic. A comparison between the reported numbers for the DP, PFP and FP indeed does not show any difference for the modeled concentration of particles in the NAAQS Impact Analysis tables of the corresponding TSDs.

7- This is consistent with the ADEQ response mentioned in Chapter A for June 18, 2024, that “the application was not updated” despite the Comments submitted by appellant.

8- In the RSPC, ADEQ attempted to justify its decision by accepting the argument that on-site assessments are not “feasible” because the Hermosa Mine “has not been built yet”. However, in the recently submitted Significant Amendment to APP No. P-512235, S32 summarizes in Table D.5.1 and D.4, the results of a 2022 geotechnical test of the top few feet from 27 “test pits”. Out of these tests only one showed a silt percentage below 5%, while the average was 16.4%, more than three times the value used throughout the DAS.

9- It is of concern that S32 did not provide recent site-specific information with which more accurate particle emission numbers for a dominant source at its mining site, could have been obtained.

- Moreover, for several years S32 is extracting and transporting large volumes of rock to build access tunnels and shafts thereby using trucks on unpaved haul roads creating the opportunity for a straightforward on-site assessment of actual rather than calculated emission - and emission control factors. Such an effort would represent not only the required “best available” model input data but could have been used to produce the adequate margin of safety to which the EPA is committed by law to adhere to.

11-In the Hermosa Mine case this margin is extremely relevant as the annual PM2.5 emission as listed in the TSD files of the PFP and FP, essentially is right at the current NAAQS safe limit of 9 microgram/m3.

Metal Fractions in Haul Road Soils

1- Issue 2: ADEQ does not disclose what metal fractions are used in the dispersion model for particles emitted by underground road traffic.

2- The subject of metal fractions in road soils was extensively reviewed by ADEQ in the RSPC in Chapter II, Section F, and summarized in the last Chapter III, Section B, under “Significant Changes To The Air Permit”. Below appellant reviews those responses.

3- As already mentioned in the previous paragraph, road emissions dominate as a source for particles and can thus be expected to be a major source for metal emissions as well. To obtain metal emission numbers, the metal fraction for each particle source needs to be known and multiplied with the particle emission rate and if not known, estimations need to use the “best available” information.

4- For non-stationary haul equipment road soils appear to be the main particle source. For this source, ADEQ used metal fractions reported in a 1991 ADEQ publication for samples that reportedly represent the average Arizona (aboveground) soil. Since the Hermosa Mine site is in a heavily mineralized mountain area, the mentioned publication does not qualify as providing the “best available” information. In appellant’s Comments the USGS report “Scientific Investigations Report 2019 – 5077” was suggested as the best available source for on-site and very recent (2020 publication year) information on metal fractions in local (aboveground) soil.

5- In the RSPC at ADEQ’s Response to Comment #77, ADEQ states: “This report was not previously known to ADEQ during the review and processing of the South32 permit application”, even though the final submission date of the DP to ADEQ was late 2023.

6- ADEQ then used the information of the report as a basis to “re- estimate” the potential-to-emit numbers for Pb and Mn and stated that it would be “more appropriate” in terms of soil location to use only part of the soil data and changed from using maximum values to average values to somehow account for road type. That, of course, led to much lower values for Pb (102.5 ppm) and Mn (702.0 ppm) than found in the USGS report as a maximum value. This action therefore undermines the widely touted claim of always using the most conservative data in the emission calculations.

7- Since further documentation was not made available on this re-estimate, it is not clear whether these values were used for only aboveground or also for underground roads.

8- If so, then underground metal emissions can be seriously underestimated as metal concentrations in underground mine stopes with highly mineralized deposits exceed those of aboveground soils by several orders of magnitude.

- The only reference to underground roads was found in the earlier mentioned summary Chapter III of the RSPC, quote

- The USGS “Scientific Investigations Report 2019–5077” report was used to re-estimate the metal HAPs emissions from the aboveground road traffic. The metal HAPs emissions from underground road traffic were also re-evaluated using the metal HAPs mass fraction of rock to be more conservative -,

end quote.

-Therefore, the following issues still need to be addressed:

(1) where can a “re-evaluation” of underground haul traffic emissions be found in in the RSPC, TSD or any other permit document, (2) what is the difference between “re-estimation” and “re-evaluation” in this context, (3) what is meant with “rock” and what is the assigned metal fraction, (4) why is the metal fraction of “ore”, which obviously is abundantly present underground with a much higher metal fraction than any other “rock”, seemingly not included in the estimation of the metal emission from underground roads, (5) how do the application spreadsheets address the re-estimated or re- evaluated metal fraction values for above - and underground roads

11- Nevertheless, in the same chapter of the RSPC, ADEA still claims that, quote,

- “these changes do not change any applicable requirements or adversely impact any modeling outcomes” -.

Clearly, further clarifications are needed before this conclusion can be accepted. Deposition and Accumulation of Particles

1- Issue 3: The deposition of metal containing particles emitted by the Hermosa Mine is not included as a factor that can cause or contribute to an exceedance of water and soil quality standards outside the Ambient Air Boundary of the Hermosa Mine.

2- This topic is acknowledged in the RSPC as an “issue”, but the response of ADEQ misses the reality of the Patagonia Mountains representing a mineralized eco-system prone to natural and anthropogenic metal mobilization processes. This phenomenon has led to demonstrated and catalogued impairments already many years before the S32 Hermosa Mine was purchased by its previous owner AMI, now a subsidiary of S32.

3- In the modeling of the dispersion of emitted pollutants, the particle size is an important parameter for estimating which fraction of the emitted volume is “lost” due to gravitational deposition or settling. These losses are very high and thus work in favor of meeting air concentration limits but work adversely when deposited on water and soil surfaces, especially when already impaired, or when deposits are accumulated over a long period of time. Such deposits become part of the food chain which is NAAQS regulated under “public welfare” using so-called “secondary” safe standards as compared to “primary” standards regulating long term inhalation-based exposure.

4- In the RSPC at ADEQ’s Response to Comment 81, ADEQ argues that since the secondary standard for Pb is the same as the primary one to which ADEQ claims it complies with, the FP is “expected to protect public welfare, including preservation of soil and water”.

5- When it comes to accumulation in soils and water over time, including after post closure, ADEQ’s Response to Comment #83 includes appreciation for the insights presented by appellant but also states that “there are neither tools nor guidelines in place to address the issue” and ADEQ thus “strongly relies on the implementation of the Dust Control Plan….”.

6- Such a plan is of little value when emission sources are underrated, and priorities misjudged but ADEQ at least is recognizing the problem and may decide to address it. 7- Here the possibly unique situation of having an emission source in an already impaired environment comes into play, as that is precisely what the Hermosa Mine in the Patagonia Mountains represents. This implies that a generally accepted and frequently enforced statute saying that a source “cannot cause or contribute to an exceedance of a quality standard”, may impose severe limits to the Hermosa Mine emissions.

8- There are no tools or guidelines needed to conclude that with many sites outside the Ambient Air Boundary of the Hermosa Mine having confirmed water and/or soil impairments, any additional anthropogenic source will violate this statute, and that includes the Hermosa Mine and any other new anthropogenic source that emits metal compounds with the potential to cause or contribute to an exceedance of applicable standards.

Emissions from Transported Ore - and Concentrate Cargo

- Issue 4: On-site and off-site cargo emissions from ore - and concentrate haul trucks are not included in the dispersion modeling of particles and metals.

2- In the RSPC at Comment #84, ADEQ re-iterates that for off-site hauling sealed containers will be used and adds that those containers are “closed to the atmosphere” and “maintain integrity in the event of a transportation incident”. The only more specific information given is that “Utilizing sealed containers will eliminate dust emissions from transported materials.” EPA does not offer its own emission factor assessment results on this topic in AP-42 and requests for documentation from a truck supplier that offers the touted “rotainers”, remain unanswered till today. Therefore, the issue of how important cargo emissions from transportation trucks are remains unaddressed as well.

Traversing Roads

1- Issue 5: Dispersion modeling has not shown compliance with any NAAQS concerning the segment of Harshaw Road that traverses the Hermosa Mine site as a public road.

2- In the RSPC, at ADEQ’s Response to Comment #89, ADEQ responds to the issue of Harshaw Road intersecting the Ambient Air Boundary the fully encloses the Hermosa Mine property, stating that this segment of the road “was appropriately designated as ambient air” like “any public road should be considered ambient air”, as per ADEQ’s 2019 guideline for modeling dispersion of air pollutants from inside an Ambient Air Boundary.

3- However, the same guidelines also state that “the ambient air boundary must fully and continuously preclude public access”. Since that is not the case with a traversing public road, the two separated properties may now be considered as one being a nearby source of the other, of which a cumulative impact assessment under PSD is considered as “routine”. Note that the Clark Mine is located SE of Harshaw Road and the Taylor Mine NW. Obviously, such a cumulative impact will show that the traversing segment of Harshaw Road will have pollutant air concentrations that are much closer to what is calculated for air inside the Ambient Air Boundary than what is calculated for ambient air. Hence ADEQ must estimate the pollutant air concentrations in ambient air over the Harshaw Road segment that traverses the Hermosa Mine as a cumulative contribution from two sources.

C. REQUESTED RELIEF

The Context of Public Health

On Air vs Soil Pollution

In 2011, Bowers et al. of environmental consulting company Gradient, Cambridge/MA, published a comprehensive environmental study of a smelter near the town of Herculaneum/MO, today owned by the Doe Run company. That company also extracts Pb ores from nearby massive deposits known as the Viburnum Trend.

The study collected soil-depth and air concentrations of Pb during 2000- 2009 when the owner implemented some emission control measures after finding too high levels of Pb in soils, for the first time in 1982. Soil samples from nearby remediated and non-remediated private properties were compared in order to estimate the rate of re-contamination under changing air emission conditions, a unique approach. The numbers found exceeded standards that were 10 times less stringent than today and eventually the plant closed in 2013 after 120 years of operation, 30 years of activism on the public health front and after dramatic tightening of NAAQS Pb standards deemed necessary by EPA in 2008.

The mentioned case study learns that the Pb accumulation ranges between 10ppm to 100ppm Pb per year, the concentration representing the average in the top one inch of soil into which airborne Pb has “mixed”. Trends observed were fitted to soil penetration models developed by the Gradient company showing good fits with penetration profiles at different smelter locations revealing the expected slow “diffusion” rate for Pb.

The study confirms that significant impairments can result from the deposition of airborne pollutants in relatively short periods of time.

The modeled metal air concentrations of the Hermosa Mine are about 10x lower and Pb compounds will be physically and chemically different in nature and therefore may have different transportation properties, but health impacts can be expected to be similar. Unfortunately, no such studies have been done for mines in Arizona, despite abundant opportunities to do so.

Air Pollution and Adverse Health Symptoms

In 2023, Dr. Brittany Krzyzanowski of the Barrow Neurological Institute in Phoenix/AZ, co-published a nationwide analysis on the risk of Parkinson Disease vs lifetime exposure to variable PM2.5 concentrations in environmental air. A so-called “decelerated response” was observed, ie the risk increase with increasing concentration slows down, but starts at concentrations well below the current NAAQS standard or even the background level as, for instance, used in the Hermosa Mine emission compliance calculation.

According to Dr. Bruce Lanphear, MD at the Simon Fraser University, Burnaby/CN, decelerating responses have also been observed between Pb concentration in blood and cognitive abilities in children as well as Pb concentration in blood and Pb concentration in soils. Also for some other chemicals decelerated responses on adverse health symptoms have been found. This supports the conclusion that there is a zero tolerance for some chemicals in the environment and with Pb known to be a persistent pollutant in our ecosystem for more than a century, today’s actions will be limited in effectively curing related health problems. Dr Lanphear testified about “no known safe level of Pb exposure” before Congress in 2017 and again in 2023 before the EPA commission on the Integrated Science Assessment for Lead. This commission is preparing an update on primary - and secondary Pb standards for 2026.

To be realized is that PM2.5 as released by the Hermosa mine can have a Pb fraction of 5%, as found in ore material, or lower, depending on the on- site source. In that case, at the 9 microgram/m3 NAAQS safe standard for PM2.5, the corresponding Pb concentration is 0.450 microgram/m3, which is three times the NAAQS limit for Pb.

The above illustrates how important a trustworthy on-site assessment is for both PM2.5 emission and metal fractions in particles to properly protect public health and the environment. Appellant therefore has made that a priority in the requests for relief as summarized below.

Requested Relief Actions

On the basis that the emission estimation issues brought forward in this appeal may lead to an exceedance of NAAQS, the Director is requested to revoke the Final Permit and require that ADEQ revises a potential re- application acting upon the following:

1. Use credible, site-specific particle emission rate - and particle metal fraction assessments as model inputs to demonstrate, with an adequate margin of safety, compliance with primary NAAQS during life-of-mine for above - and underground haul road traffic

2. Demonstrate that even when Hermosa Mine emissions do comply with secondary NAAQS for Pb at the ambient air boundary, deposition of Pb containing particles outside the Ambient Air Boundary does not cause or contribute to an exceedance of water or soil quality standards for Pb during and after life-of-mine

3. Demonstrate that Hermosa Mine air pollutants dispersed on public roads that intersect the ambient air boundary and traverse the Hermosa Mine property, do not exceed primary NAAQS and do not lead to accumulated metal concentrations from airborne metal containing particles that cause or contribute to an exceedance of soil quality standards during the life- of-mine and after closure

4. Demonstrate that cargo emissions from ore - and concentrate transportation trucks do not lead to NAAQS exceedances and accumulated deposition concentrations from airborne metal containing particles that cause or contribute to an exceedance of soil quality standards, on-site or off-site the Hermosa Mine, during life-of-mine