Coalition Joins Conservation Groups in Urging Rejection of Arctic Mine Permit

Alaska Community Action on Toxics * Alaska Wilderness League* All About Adventure * Brooks Range Council * Center for Biological Diversity * Coalition to Protect America’s National Parks * Earthworks * Great Old Broads for Wilderness * National Parks Conservation Association * Northern Alaska Environmental Center * Protect the Kobuk * Sierra Club * The Wilderness Society Wilderness Watch¹

Nov. 2, 2026

Col. Victor Trujillo, Commander
U.S. Army Corps of Engineers, Regulatory Division
Alaska District
1046 Marks Road
Fort Wainwright, Alaska 99703

Re: Arctic Mine Project Environmental Impact Statement, POA-2019-00081

Dear Col. Trujillo:

On behalf of the above-listed organizations and our members, we provide the attached comments on Ambler Metals’ Clean Water Act 404(b) permit application for the Arctic Mine project.

The proposed mine, which would be located at the end of the proposed Ambler Road, would have significant, long-lasting, and far-reaching environmental consequences, with potentially disastrous results for local communities, water quality, fisheries, wildlife (including the Western Arctic Caribou Herd), recreation, and traditional ways of life.

Pristine waterways will be impounded, filled, and polluted. Toxic tailings and acid-producing mine waste will be permanently deposited at the headwaters of Subarctic Creek. Mining operations and access roads will produce large amounts of fugitive dust. Native fish habitat will disappear from some streams, and wildlife habitat will be fragmented by roads and other mining infrastructure, likely disrupting millennia-old migration patterns.

The Western Arctic Caribou Herd is essential to the subsistence, food security and lifeways of the people of the region. Industrial development and road construction would cut through caribou migration routes, threatening habitat connectivity and access to traditional hunting grounds, placing already vulnerable food systems at further risk.

The mine is closely connected to, and would be accessed by, the proposed Ambler road. If the mine and the road are built, trucks filled with ore would travel through Gates of the Arctic National Preserve daily, threatening the park’s wild nature. Mining traffic along the proposed Ambler road is also a matter of grave concern for local communities, several of whom have passed resolutions opposing the proposed road.

Against the certainty of environmental harm, the mine’s public benefits are speculative, at best. As the project’s statement of need shows, much of the value generated by mining will flow to the international mining conglomerates that own Ambler Metals, and their shareholders.² Mine products will be exported to Asia for additional processing.³ There may be some indirect economic benefits for the affected communities in the form of jobs and royalty payments, but these will, in all likelihood, be thinly spread over a large geographic area and limited by lack of access—there are no plans to connect the Ambler road to communities along the proposed route.

In light of the proposed mine’s substantial impacts and speculative benefits, we urge the Corps to deny the permit, as it would be contrary to the public interest, cause significant degradation of aquatic resources, and have unmitigable impacts at both the local and regional scales.

At the very least, the Corps must prepare a detailed EIS that fully evaluates all of the proposed mine’s direct, indirect, and cumulative impacts, including impacts associated with the proposed use of the Ambler road. This includes impacts from processing facilities (particularly tailings disposal facilities), power generation facilities, ore transport and export facilities (including the impacts of spills and fugitive dust), airstrips, and more. There will be a direct loss of habitat from the mine footprint, access road, power lines, and all associated mine activities that must be considered, as well as impacts beyond the mine footprint due to noise, blasting, lights, worker housing, and transportation.

The environmental review must also include a detailed and site-specific evaluation of the impacts on caribou populations, subsistence practices and Indigenous self-determination. Meaningful consultation with affected communities and the incorporation of Indigenous knowledge must be central to this process. In addition, we expect the Corps to provide, consistent with its statutory obligations, meaningful opportunities for public participation, including the ability to review and comment on a draft EIS and related documents, and public hearings.

If you have any questions or wish to clarify anything in our comments, please do not hesitate to contact Scott Lake at sl***@******es.org. Thank you for your prompt attention to our comments.

Pamela Miller
Executive Director
Alaska Community Action on Toxics

Sally Sharp
Grassroots Leadership Program Manager
Great Old Broads for Wilderness

Maddie Halloran
Alaska State Director
Alaska Wilderness League

Ronald Yarnell
Owner
All About Adventure

John Gaedeke
Chairman
Brooks Range Council

Cooper Freeman
Alaska Director
Center for Biological Diversity

Cheryl Schreier
Executive Board Chair
Coalition to Protect America’s National Parks

Jared Naimark
Western Mining Senior Manager
Earthworks

Jim Adams
Alaska Regional Director
National Parks Conservation Association

Krystal Lapp
Interim Executive Director
Northern Alaska Environmental Center

China Kantner
Founder
Protect the Kobuk

Jackie Feinberg
National Lands Conservation Campaign
Manager
Sierra Club

Matt Jackson
Senior Manager, Alaska
The Wilderness Society

Dan Brister
Staff Attorney
Wilderness Watch

Footnotes

1. Comments prepared by Trustees for Alaska ↩
2. See U.S. Army Corps of Engineers, Notice of Intent to Prepare an Environmental Impact Statement (Sept. 18, 2026) [hereinafter “Public Notice”] at 4 (stating that “[t]he primary need for the Project is to bring domestic supplies of critical minerals to market and maximize value to Ambler Metals LLC.”) Ambler Metals is a joint venture partnership between Trilogy Metals Inc. a Canadian company, and South32 Limited, an Australian company. Ambler Metals, Fast-41 Initiation Notice, Arctic Project (April 30, 2026) [hereinafter “Fast-41 Initiation Notice”] at 1. ↩
3. Staples, Paul et al., Arctic Feasibility Study, Alaska, U.S.A., NI 43-101 Technical Report (Aug. 20, 2020) [hereinafter “Feasibility Study”] at 19-1. ↩
4. See generally Bureau of Land Management, Record of Decision, Ambler Road (June 2024). ↩
5. Id. at 2. ↩
6. Id. ↩
7. Id. ↩
8. Id. at 2-3, 8, 13. ↩
9. Fast-41 Initiation Notice, supra n.2 at 2; Public Notice, supra n.2, at 2. ↩
10. 33 U.S.C. § 1251(a). ↩
11. Id. § 1251(a)(2). ↩
12. Id. § 1311(a). ↩
13. Id. § 1362(6). ↩
14. See 33 C.F.R. § 323.2(e)(1); 40 C.F.R. § 232.2. ↩
15. 33 C.F.R. § 323.2(c); 40 C.F.R. § 232.2. ↩
16. 33 U.S.C. § 1344; 40 C.F.R. pt. 230. ↩
17. 33 C.F.R. § 320.4(b)(1); see also id. § 320.4(b)(2) (identifying eight types of wetland functions important to the public interest). ↩
18. Id. § 230.10. ↩
19. Id. § 230.12(a)(3)(iv); see also 33 C.F.R. §§ 320.2(f) and 320.4(a)(1). ↩
20. 42 U.S.C. § 4331. ↩
21. See generally 42 U.S.C. §§ 4331, 4332(1). ↩
22. 42 U.S.C. §§ 4332(2)(C), 4336(b)(1). ↩
23. 42 U.S.C. § 4332(2)(C). ↩
24. Robertson v. Methow Valley Citizens Council, 490 U.S. at 349; see also Vermont Yankee Nuclear Power Corp. v. Natural Resources Defense Council, 435 U.S. 519, 553 (1978) (“NEPA places upon an agency the obligation to consider every significant aspect of the environmental impact of a proposed action”). ↩
25. Pit River Tribe v. U.S. Forest Serv., 469 F.3d 768, 787 (9th Cir. 2006). ↩
26. 54 U.S.C. § 306108. ↩
27. Id. § 302706(b). ↩
28. 36 C.F.R. § 800.1(a). ↩
29. Muckleshoot Indian Tribe v. U.S. Forest Serv., 177 F.3d 800, 805 (9th Cir. 1999) (citation omitted). ↩
30. 36 C.F.R. § 800.3(f)(2). ↩
31. Id. §§ 800.1(c); 800.6(a); 800.8(a)(2). ↩
32. Id. § 800.4(a)(1), (b). ↩
33. Id. § 800.16(d). ↩
34. 36 C.F.R. § 800.16(l)(1); 54 U.S.C. § 300308. ↩
35. Id. § 800.16(l)(1); 54 U.S.C. § 302706(a). ↩
36. Patricia L. Parker & Thomas F. King, National Register Bulletin: Guidelines for Evaluating and Documenting Traditional Cultural Properties 1 (rev. ed. 1998). ↩
37. Charles A. Birnbaum, Preservation Briefs: Protecting Cultural Landscapes: Planning, Treatment and Management of Historic Landscapes 1 (1994). ↩
38. See Muckleshoot, 177 F.3d at 807; ACHP, Information Paper on Cultural Landscapes: Understanding and Interpreting Indigenous Places and Landscapes 1 (Oct. 11, 2016). ↩
39. 36 C.F.R. § 800.16(l)(2); see id. § 60.4 (National Register criteria). ↩
40. Id. § 800.4(b)(1). ↩
41. Id. ↩
42. Id. § 800.4(c)(1). ↩
43. Id. ↩
44. Id. § 800.5(a). ↩
45. Mont. Wilderness Ass’n v. Connell, 725 F.3d 988, 1005 (9th Cir. 2013). ↩
46. 36 C.F.R. § 800.5(a)(1). ↩
47. Memo from ACHP Office Gen. Counsel to ACHP Staff, Recent Court Decision Regarding the Meaning of “Direct” in Sections 106 and 110(f) of the National Historic Preservation Act, at 2 (June 7, 2019). ↩
48. Id. at 2. See Nat’l Parks Conservation Ass’n v. Semonite, 916 F.3d 1075, 1088 (D.C. Cir. 2019). ↩
49. 36 C.F.R. § 800.5(a)(1). ↩
50. Id. § 800.5(a)(2)(i), (iv), (v), (vii). ↩
51. Id. § 800.6(a). ↩
52. 36 C.F.R. § 800.16(f). ↩
53. Id. § 800.2(c)(2)(ii); 54 U.S.C. § 302706(b). ↩
54. See id. §§ 800.4(a)(4), (b), (c)(1), 800.5(a), 800.6(a). ↩
55. Id. § 800.2(c)(2)(ii)(A). ↩
56. Quechan Tribe v. U.S. Dept. Interior, 755 F. Supp. 2d 1104, 1109 (S.D. Cal. 2010). ↩
57. Id. at 1108. ↩
58. Id. at 1118. ↩
59. 36 C.F.R. § 800.2(c)(2)(ii)(B)-(C). ↩
60. See Feasibility Study, supra n.3, at 1-14 – 1-15. ↩
61. Id. at 18-0. ↩
62. Id. at 1-12, 1-21. ↩
63. Id. at 1-21. ↩
64. Ambler Minng District Industrial Access Project, U.S. Army Corps of Engineers 404 Revised Permit Application Narrative, POA-2013-396, February 2020, at 6. ↩
65. Id. at 1. ↩
66. Yereth Rosen, The Environmental Review Process Is Beginning for a Controversial New Road in Alaska’s Arctic, Arctic Today, Dec. 6, 2017. ↩
67. Nathaniel Herz, As Alaska fuel costs spike, this state agency chose three tiny villages for $25,000 relief checks, Alaska Beacon, Oct. 19, 2026. ↩
68. 598 U.S. 651 (2023). ↩
69. 40 C.F.R. § 230.10(a). ↩
70. Id. § 230.10(c). ↩
71. Id. § 230.1(d). ↩
72. Id. § 230.10(c). ↩
73. Id. ↩
74. Id. § 230.11. ↩
75. Id. § 230.12(a)(3)(iv); see also 33 C.F.R. §§ 320.2(f), 320.4(a)(1). ↩
76. 40 C.F.R. § 230.10(a)(3); Friends of the Santa Clara River v. U.S. Army Corps of Eng’rs, 887 F.3d 906, 912, 916 (9th Cir. 2018). ↩
77. 40 C.F.R. § 230.10(a)(2). ↩
78. Id. § 230.10(a)(1). ↩
79. See Butte Env’t Council v. U.S. Army Corps of Eng’rs, 620 F.3d 936, 945 (9th Cir. 2010); Friends of the Earth v. Hintz, 800 F.2d 822, 835 (9th Cir. 1986). ↩
80. Friends of the Earth, 800 F.2d at 835–36. ↩
81. Louisiana Wildlife Fed’n, Inc. v. York, 761 F.2d 1044, 1048 (5th Cir. 1985) (noting that the Corps had properly chosen “alternatives that reduced both the applicants’ profit and the economic efficiency of their proposed operations in order to preserve other environmental values”). ↩
82. See 40 C.F.R. § 230.12(a)(3)(i), (iv). ↩
83. Id. § 230.10(d). ↩
84. 33 C.F.R. § 332.1(c)(3). ↩
85. Id. § 332.1(c)(3). ↩
86. Id. § 332.3(b). ↩
87. Id. § 332.3(a)(1). ↩
88. Id. § 332.3(f). ↩
89. See Lindsey N. Bowker & David Chambers, In the Dark Shadow of the Supercycle Tailings Failure Risk & Public Liability Reach All Time Highs, Bowker Associates Science & Research in the Public Interest & Center for Science in Public Participation (Oct. 21, 2017). ↩
90. See Earthworks, Safety First: Guidelines for Responsible Mine Tailings Management (May 31, 2022). ↩
91. Lindsay Newland Bowker & David M. Chambers, The Risk, Public Liability, & Economics of Tailings Storage Facility Failures (July 21, 2015). ↩
92. Id. at 2. ↩
93. David Chambers & Brettwood Higman, Long Term Risks of Tailings Dam Failure (Oct. 2011); see also David Chambers, Long Term Risk of Releasing Potentially Acid Producing Waste Due to Tailings Dam Failure. ↩
94. A UNEP Rapid Response Assessment, United Nations Environment Programme and GRID- Arendal, Nairobi and Arendal, Charles Roche, Kristina Thygesen, & Elaine Baker eds. (2017). ↩
95. Id. at 6. ↩
96. Id. at 16. ↩
97. See Bowker & Chambers, supra n.89 at 3. ↩
98. Id. at 9. ↩
99. Id. at 17–18. ↩
100. Michael Davies, Tailings Impoundment Failures: Are Geotechnical Engineers Listening? Waste Geotechnics (2002). ↩
101. Id. at 5. ↩
102. Id. ↩
103. Id. ↩
104. Id. ↩
105. See Bowker and Chambers, supra n.89 at 5. ↩
106. Id. at 6; see also Province of British Columbia, Independent Expert Engineering Investigation and Review Panel, Report on Mount Polley Tailings Storage Facility Breach (Jan. 30, 2015). ↩
107. Province of British Columbia, supra n.104, at 119. ↩
108. See Bowker & Chambers, supra n.89 at 6; see also Flavio Fonseca do Carmo, et al., Fundao Tailings Dam Failures: The Environmental Tragedy of the Largest Technical Disaster of Brazilian Mining in Global Context, Associação Brasileira de Cienca Ecologica e Conservacao (July 2017); Fatal Brazilian Mine Waste Disaster Shows Modern Mining Is Increasingly Dangerous, Earthworks (Nov. 6, 2015). ↩
109. Court-Ordered Study for the Donlin Gold Mine in Alaska Shows Devastation from a Tailings Spill but Agencies Have More to Do, Earthjustice (Sept. 23, 2026). ↩
110. Id. ↩
111. See Federal Emergency Management Agency, Federal Guidelines for Dam Safety, Earthquake Analyses and Design of Dams (2005); Strength of Materials for Embankment Dams, United States Society on Dams (2007). ↩
112. Kendra Zamzow, CSP2, Ambler Road and Mining District Information Brief (Feb. 22, 2017). ↩
113. Feasibility Study, supra n.3, at 9-16. ↩
114. Id. at 18-19. ↩
115. U.S. Environmental Protection Agency, National Hardrock Mining Framework at B-6 (Sept. 1997) ↩
116. Id. ↩
117. Id. ↩
118. Id. at B-7 ↩
119. Id. ↩
120. Id. ↩
121. See Fairbanks Fold Mining Inc. Cyanide Water Spill, Alaska Business (Aug. 25, 2012) ↩
122. See EPA, supra n.113, at B-6 – B-7. ↩
123. See Earthworks, Alaska Mining Spills (April 6, 2022). ↩
124. Earthworks, The Track Record of Environmental Impacts Resulting from Pipeline Spills, Accidental Releases and Failure to Capture and Treat Mine Impacted Water, U.S. Gold Mines Spills & Failures Report (July 20, 2017). ↩
125. Id. at 8. ↩
126. Id. ↩
127. Id. ↩
128. Earthworks, U.S. Copper Porphyry Mines (Aug. 6, 2012). ↩
129. Id. at 5. ↩
130. Feasibility Study, supra n.3, at 1-16. ↩
131. Feasibility Study, supra n.3, at 16-18. ↩
132. Feasibility Study, supra n.3, at 9-11. ↩
133. Id. at 18-15. ↩
134. Id. at 18-4. ↩
135. Id. at 20-4. ↩
136. Id. ↩
137. See Alt, K. T. 1969. Taxonomy and ecology of the inconnu, Stenodus leucichthys nelma, in Alaska. Biological Papers of the University of Alaska, No. 12, pp. 1–63; Brown, R. J., K. G. Shink, and J. B. Olsen. 2025. Yukon River Inconnu: Biology, distribution, and migration. Transactions of the American Fisheries Society 154(5):505–522; Fraley, K. M., J. C. Leppi, M. B. Courtney, A. Whiting, W. K. Carter III, B. Scanlon, A. C. Seitz, and M. D. Robards. In press. Changing coastal distribution and life-history patterns of Inconnu in northwest Alaska. Arctic Science; Georgette, S., and H. Loon. 1990. Subsistence and sport fishing of sheefish on the upper Kobuk River, Alaska. Alaska Department of Fish and Game, Division of Subsistence, Technical Paper No. 175, Kotzebue, Alaska; Georgette, S., and H. Loon. 1993. Subsistence use of fish and wildlife in Kotzebue, a northwest Alaska regional center. Alaska Department of Fish and Game, Division of Subsistence, Technical Paper No. 167; Savereide, J. W. 2001. Under-ice gillnet harvest of sheefish in Hotham Inlet in 2000–2001. Final report for Fisheries Resource Monitoring Program Study No. 00-020. Alaska Department of Fish and Game, Division of Sport Fish, Fairbanks, Alaska, for the U.S. Fish and Wildlife Service, Office of Subsistence Management; Savereide, J. W., and J. Huang. 2016. Spawning location, run timing, and spawning frequency of Kobuk River sheefish 2008–2014. Alaska Department of Fish and Game, Fishery Data Series No. 16-31, Anchorage, Alaska. ↩
138. See also 50 C.F.R. § 600.805-815 and 50 C.F.R. § 600.905-930. ↩
139. 50 C.F.R. § 600.815(a)(1). ↩
140. 16 U.S.C. § 1802(10). ↩
141. 50 C.F.R. § 600.915. ↩
142. Id. at § 600.920. ↩
143. Id. at § 600.920(d), (e)(3). ↩
144. 16 U.S.C. § 1855(b)(4)(a). ↩
145. See 50 C.F.R. § 600.920(f). ↩
146. For example, a survey on the Kenai Peninsula found that out of 270 culverts, 34% provided only “marginal” fish passage and another 48% provided “inadequate” passage. Kenai Watershed Program, Science in Action: Culvert Assessment (visited Oct. 26, 2026). Similarly, a 2022 survey of 586 culverts in the Matanuska-Susitna Valley found that 62% of culverts or more may be barriers to salmon passage. Matanuska-Susitna Borough, Fish Passage Program (2022). ↩
147. Fullman, T. 2024. Sensitive species and habitats in the NPR-A: Caribou. In The Wilderness Society. Assessment of ecological and cultural values within the National Petroleum Reserve- Alaska. pp. 15-53, at 15-16. DOI: 10.5281/zenodo.15177945; Chen, W.J., et. al., 2017, Does Dust from Arctic Mines Affect Caribou Forage? Journal of Environmental Protection, 8, 258-276, at 259; Russell DE, Gunn A, Kutz S. 2018: Migratory Tundra Caribou and Wild Reindeer. In: Arctic Report Card 2018, p.67-73. ↩
148. Fullman 2024, supra n.147, at 16. ↩
149. Id. ↩
150. Id. ↩
151. Id.; Dau J. 2015. Units 21D, 22A, 22B, 22C, 22D, 22E, 23, 24 and 26A. Chapter 14, pages 14- 1 through 14-89 In Harper P, McCarthy LA, editors. Caribou management report of survey and inventory activities 1 July 2012–30 June 2014. Alaska Department of Fish and Game, Species Management Report ADF&G/DWC/SMR-2015-4, Juneau; Lenart E. 2021. Central Arctic caribou management report and plan, Game Management Unit 26B: Report period 1 July 2012 – 30 June 2017, and plan period 1 July 2017 – 30 June 2022. Alaska Department of Fish and Game, Species Management Report and Plan ADF&G/DWC/SMR&P-2021-2, Juneau, AK, USA; Caikoski JR. 2020. Porcupine caribou herd management report and plan, Game Management Unit 25A, 25B, 25D, and 26C: Report period 1 July 2012 – 30 June 2017, and plan period 1 July 2017 – 30 June 2022. Alaska Department of Fish and Game, Species Management Report and Plan ADF&G/DWC/SMR&P-2020-22, Juneau, AK, USA. ↩
152. Fullman 2024, supra n.147, at 17. ↩
153. Herd declines to critical level, Caribou Trails No. 26 (Summer 2026). ↩
154. Fullman 2024, supra n,147, at 15. ↩
155. Fullman TJ, Joly K, Gustine DD, Cameron MD. 2025. Behavioral responses of migratory caribou to semi-permeable roads in Arctic Alaska. Scientific Reports 15, 24712. ↩
156. Id. ↩
157. Id. ↩
158. Fullman 2024, supra n.147, at 19, 21. ↩
159. Fullman 2024, supra n.144, at 21-22; Boulanger J, Kite R, Campbell M, Shaw J, Lee D, Atkinson S. 2024. Estimating the effects of roads on migration: a barren‑ground caribou case study. Canadian Journal of Zoology 102, 476-493. ↩
160. See Seidler, Renee G., Long, Ryan A., Berger, Joel, Bergen, Scott, and Beckmann, Jon P., Identifying Impediments to Long-Distance Mammal Migrations, Conservation Biology, (2015) Volume 29, No. 1, 99-109, at 8-9. ↩
161. Fullman 2024, supra n.147, at 21; Parker KL, Barboza PS, Gillingham MP. 2009. Nutrition integrates environmental responses of ungulates. Functional Ecology 23, 57-69. ↩
162. Fullman 2024, supra n.147, at 21; Northrup JM, Anderson Jr. CR, Wittemyer G. 2015. Quantifying spatial habitat loss from hydrocarbon development through assessing habitat selection patterns of mule deer. Global Change Biology 21(11), 3961-3970. ↩
163. Fullman 2024, supra n.147, at 21; Parker et al 2009, supra n.161. ↩
164. Fullman 2024, supra n.147, at 21. ↩
165. Vistnes, Ingunn, Nellemann, Christian, The matter of spatial and temporal scales: a review of reindeer and caribou response to human activity, Polar Biology (2008) 31:399–407, at 404. ↩
166. Id.; Fullman 2024, supra n.147, at 15; Johnson HE, Golden TS, Adams LG, Gustine DD, Lenart EA. 2020. Caribou use of habitat near energy development in Arctic Alaska. The Journal of Wildlife Management 84(3), 401-412. ↩
167. Vistnes and Nellemann 2008, supra n.165, at 403. ↩
168. Chen et al. 2017, supra n.147, at 273; Fullman 2024, supra n.147, at 22; Neitlich PN, Berryman S, Geiser LH, Mines A, Shiel AE. 2022. Impacts on tundra vegetation from heavy metal-enriched fugitive dust on National Park Service lands along the Red Dog Mine haul road, Alaska. PLoS ONE 17(6), e0269801. ↩
169. Chen et al. 2017, supra n.147, at 273. ↩
170. Fullman 2024, supra n.147, at 22. ↩
171. Id. at 22. ↩
172. Id.; Walker DA, Everett KR. 1987. Road dust and its environmental impact on Alaskan taiga and tundra. Arctic and Alpine Research 19(4), 479-489. ↩
173. Fullman 2024, supra n.147, at 22; Kostial K, Kello D, Jugo S, Rabar I, Maljković T. 1978. Influence of age on metal metabolism and toxicity. Environmental Health Perspectives 25, 81-86. ↩
174. Fullman 2024, supra n.147, at 15. ↩
175. Id. at 23; Chen et al. 2017, supra n.144, at 259. ↩
176. Fullman 2024, supra n.147, at 23-24; Hansen BB, Aanes R, Herfindal I, Kohler J, Sæther B-E. 2011. Climate, icing, and wild arctic reindeer: past relationships and future prospects. Ecology 92, 1917-1923; Hansen BB, Isaksen K, Benestad RE, Kohler J, Pedersen AO, Loe LE, Coulson SJ, Larsen JO, Varpe O. 2014. Warmer and wetter winters: characteristics and implications of an extreme weather event in the High Arctic. Environmental Research Letters 9, 114021; Forbes BC, Kumpula T, Meschtyb N, Laptander R, Macias-Fauria M, Zetterberg P, Verdonen M, Skarin A, Kim K-Y, Boisvert LN, Stroeve JC, Bartsch A. 2016. Sea ice, rain-on-snow and tundra reindeer nomadism in Arctic Russia. Biology Letters 12, 20160466; Albon SD, Irvine RJ, Halvorsen O, Langvatn R, Loe LE, Ropstad E, Veiberg V, Van der Wal R, Bjorkvoll EM, Duff EI, Hansen BB, Lee AM, Tveraa T, Stein A. 2017. Contrasting effects of summer and winter warming on body mass explain population dynamics in a food-limited Arctic herbivore. Global Change Biology 23, 1374-1389. ↩
177. Fullman 2024, supra n.147, at 23-24; Leblond M, St-Laurent M-H, Cote SD. 2016. Caribou, water, and ice – fine-scale movements of a migratory arctic ungulate in the context of climate change. Movement Ecology 4, 14. ↩
178. Fullman 2024, supra n.147, at 24; Kafle P, Peacock SJ, Grond S, Orsel K, Kutz S. 2018. Temperature-dependent development and freezing survival of protostrongylid nematodes of Arctic ungulates: implications for transmission. Parasites & Vectors 11, 400. ↩
179. John Boulanger & Gordon B. Stenhouse, The Impacts of Roads on the Demography of Grizzly Bears in Alberta, PloS ONE (Dec. 22, 2014). ↩
180. See State of Alaska, Dep’t of Health & Social Servs., Assessment of the Potential Health Impacts of Climate Change in Alaska VI-VII (2018). ↩
181. See Bureau of Land Management, supra note 4. ↩
182. See Feasibility Study, supra n.3, at 19-1. ↩

Detailed Comments

CONTENTS INTRODUCTION ………………………………………………………………………………………………………….. 6

LEGAL FRAMEWORK ………………………………………………………………………………………………….. 8

I. Clean Water Act Section 404 …………………………………………………………………………………. 8

II. The National Environmental Policy Act (NEPA) ……………………………………………………… 9

III. National Historic Preservation Act Section 106. …………………………………………………. 10

DISCUSSION ………………………………………………………………………………………………………………. 14

I. The EIS Must Consider Impacts from the Construction and Operation of the Ambler Road ………………………………………………………………………………………………………………………… 14

II. The Corps Must Identify and Protect All Jurisdictional Waters ………………………………… 16

III. The EIS Must Address Compliance with the 404(b)(1) Guidelines …………………………… 16

A. The Corps Cannot Approve the Permit if it Would Cause Significant Degradation ….. 16

B. The Corps Must Select the Least Environmentally Damaging Practicable Alternative 18

C. The Corps Should Require Compensatory Mitigation for any Unavoidable Impacts .. 19

IV. Impacts of Hardrock Mining. ……………………………………………………………………………. 20

A. Tailings Dam Failure ……………………………………………………………………………………….. 21

B. Tailings Leaks ………………………………………………………………………………………………… 25

C. Acid Mine Drainage ………………………………………………………………………………………… 26

D. Toxic Materials and Waste ……………………………………………………………………………….. 27

V. Transportation Impacts ……………………………………………………………………………………….. 31

VI. Reclamation, Long-Term Management, and Financial Assurances ………………………… 31

VII. Wetlands and Aquatic Ecosystems …………………………………………………………………….. 33

A. Water Quality …………………………………………………………………………………………………. 34

B. Water Quantity/Water Balance ………………………………………………………………………….. 34

C. Water Treatment ……………………………………………………………………………………………… 36

VIII. Fish ……………………………………………………………………………………………………………….. 37

A. Copper Impacts on Fisheries …………………………………………………………………………….. 38

B. Essential Fish Habitat ……………………………………………………………………………………… 39

IX. Road Corridors & Culverts ………………………………………………………………………………. 39

X. Wildlife Impacts …………………………………………………………………………………………………. 40

A. Caribou ………………………………………………………………………………………………………….. 41

B. Birds ……………………………………………………………………………………………………………… 45

C. Brown Bears…………………………………………………………………………………………………… 46

XI. Air Quality and Emissions ……………………………………………………………………………….. 47

XII. Geophysical Impacts ……………………………………………………………………………………….. 49

XIII. Climate Change ………………………………………………………………………………………………. 50

XIV. Subsistence Impacts ………………………………………………………………………………………… 51

XV. Public Health ………………………………………………………………………………………………….. 52

XVI. Invasive Species ……………………………………………………………………………………………… 53

XVII. Environmental Justice ……………………………………………………………………………………… 53

XVIII. Federal Conflicts of Interest ………………………………………………………………………….. 54

INTRODUCTION

The Arctic Project is located along the south slope of the Brooks Range, which separates the Arctic region from the interior of Alaska. Nearby surface water includes Subarctic Creek, the Shungnak and Kogoluktuk Rivers, the Kobuk River, and numerous small lakes. The Arctic Project is located at the eastern end headwaters of Subarctic Creek, a tributary of the Shungnak River to the west, along a ridge between Subarctic Creek and the Kogoluktuk River Valley. Both the Shungnak and Kogoluktuk rivers flow into the Kobuk River. The area is characterized by steep and rugged terrain with high topographic relief.

The Kobuk Valley is within the transition zone between boreal forest and Arctic tundra. Spruce, birch, and poplar are found in portions of the valley, with a ground cover of lichens (caribou moss). Willow and alder thickets and isolated cottonwoods follow drainages, and alpine tundra is found at higher elevations. Tussock tundra and low, heath-type vegetation covers most of the valley floor. Intermittent permafrost is found at the mine site and throughout the region.

Wildlife in the Project area is typical of Arctic and subarctic fauna. Larger animals include caribou, moose, Dall sheep, bears (grizzly and black), wolves, wolverines, coyotes, lynx and foxes. Although there are no anadromous fish species in the upper reaches of the Shungnak and Kogoluktuk Rivers due to natural fish barriers, anadromous fisheries exist downstream of these reaches and may be affected by changes in water quality and quantity from the proposed mine. Other fish species such as trout, sculpin, and grayling are common throughout the Shungnak and Kogoluktuk watersheds. The Western Arctic Caribou Herd migrates through the project area once a year, heading south in late August through October from their summer range north of the Brooks Range. The mine site is northeast of the communities of Kobuk and Shungnak

According to the Corps’ public notice and other publicly available permitting documents, the proposed open-pit Arctic mine project (project or mine) would process approximately 11,000 tons of ore per day, primarily producing copper, zinc, and lead concentrates, with gold and silver also expected to be recovered. According to the public notice, mining is expected to last approximately 13 years, but the mine may require long-term or perpetual management following closure. The project includes the following major components:

• An open mine pit;
• A tailings impoundment in the Subarctic Creek watershed that will hold approximately 40 million tons of tailings;
• A waste-rock dump that will hold approximately 300 million tons of waste rock;
• A mill/processing facility that will process approximately 11,000 tons of ore per day;
• Power generation and fuel storage facilities;
• A 27-mile transportation corridor connecting the mine to the Ambler road, the Bornite camp, and the Dahl creek airstrip;

The proposed mine and related facilities would have a total footprint of approximately 1,727 acres.

The mine is closely tied to the proposed Ambler road, and as such the impact of the mine and the road should be considered together. The Ambler road corridor would cross 2,900 streams, 1,794 acres of wetlands, and 11 major rivers, including the Kobuk Wild River. This will impact countless acres of wetlands that provide habitat for salmon, whitefish, sheefish and other species of extreme importance to the ecosystem and communities throughout the region. The road would also cross Gates of the Arctic National Preserve and would run near several communities, including Bettles, Evansville, Shungnak, Kobuk, and Ambler.⁴

The proponent of the Ambler Road, the Alaska Industrial Development and Export Authority (AIDEA) has proposed a road construction schedule that would occur in phases. A Phase I pioneer road would be built first, but would only be usable from August through April, with use in the spring/summer months restricted due to the shallow embankment construction and spring break up conditions.⁵ Phase II would construct a single-lane, gravel-surfaced roadway with year-round access.⁶ At its final stage, the road would be a two-lane, gravel-surfaced roadway.⁷ The road would require gravel mines roughly every 5 miles to provide the material needed to build the road—some of which may contain asbestos, a carcinogen—as well as maintenance stations, airstrips, and camps.⁸

Several communities and groups directly impacted by the project have passed resolutions opposing the proposed road: Native Villages of Huslia and Koyukuk, and the Kobuk Traditional Council, Allakaket, Ruby and Evansville Tribal Councils, Galena, Evansville Inc., Bettles City Council, and Tanana Chiefs Conference. Other local groups and communities have spoken out in opposition to the road: Native Villages of Nulato, Kaltag, Alatna, and the Western Interior and Northwest Arctic Subsistence Regional Advisory Councils.

The direct, indirect, and cumulative effects of the proposed road are likely to be far-reaching and dramatic. The construction, maintenance, and use of the road and its river crossings will negatively impact subsistence, wildlife, vegetation, permafrost, and water resources in an area already under stress from climate change.

The mine would produce ore concentrates, which require further processing. The concentrates would be transported by truck via the Ambler road to the Dalton Highway. From there, the trucks would proceed to Fairbanks, where the concentrates would be offloaded onto rail cars and transported to Anchorage for shipping to final processing in Asia.⁹

Although the Ambler road likely meets the technical definition of a “connected action,” as it would have no purpose but for the proposed mines in the Ambler District and vice versa, see Section I, below, this is ultimately irrelevant, as an accurate and informative examination of the proposed mine’s impacts on this remote region of Alaska must necessarily include its means of access. An analysis that omits impacts from the Ambler road, or transportation of ore concentrate along existing routes to Anchorage, would provide only a piece of the picture, and thus obscure the full scope of the mine’s impacts.

LEGAL FRAMEWORK

I. Clean Water Act Section 404

Congress enacted the Clean Water Act (CWA) in 1972 to “restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.”¹⁰ The Act sets several goals, including attainment and preservation of “water quality which provides for the protection and propagation of fish, shellfish, and wildlife …”¹¹ To further its goals, the Act prohibits “discharge of any pollutant” into navigable waters except in accordance with the Act’s terms.¹² The term “pollutant” encompasses not only chemical and biological materials but also, “dredged and fill material,” e.g., rock and sand.¹³ Pollutants are known as “fill material” when their discharge either replaces any portion of a water of the United States with dry land or changes the bottom elevation of a water body.¹⁴ The term “dredged material” means “material that is excavated or dredged from waters of the United States.”¹⁵

The Corps issues permits for the discharge of dredged or fill material pursuant to section 404 and subject to the Corps’ and EPA’s 404(b)(1) Guidelines (Guidelines).¹⁶ Corps regulations governing the issuance of 404 permits declare that “[m]ost wetlands constitute a productive and valuable public resource, the unnecessary alteration or destruction of which should be discouraged as contrary to the public interest.”¹⁷

The Guidelines impose important limitations on when a section 404 permit may be issued. 40 C.F.R. pt. 230. The Guidelines prohibit the permitting of any discharge of dredged or fill material:

(1) if a practicable alternative to the proposed discharge would have less adverse impact on the aquatic ecosystem; (2) if the discharge will cause or contribute to significant degradation of the environment; and (3) unless all appropriate steps have been taken to minimize potential adverse impacts.¹⁸ The Corps cannot authorize a discharge without “sufficient information to make a reasonable judgment as to whether the proposed discharge will comply with [the section 404(b)(1)] Guidelines.”¹⁹

II. The National Environmental Policy Act (NEPA)

Congress enacted NEPA to ensure that the federal government protects and enhances the natural environment, and engages with the public in doing so.²⁰ NEPA’s twin aims are to ensure that federal agencies take a hard look at the environmental impacts of their proposed actions before taking an action and to ensure that agencies provide relevant information to the public so the public can play a role in both the decision-making process and the implementation of the decision.²¹ NEPA requires federal agencies to prepare a detailed EIS for every major federal action that will have a significant impact on the quality of the human environment.²² An EIS must consider (1) “reasonably foreseeable environmental effects of the proposed agency action,” (2) “any reasonably foreseeable adverse environmental effects which cannot be avoided,” (3) “a reasonable range of alternatives to the proposed action,” (4) “the relationship between local short-term uses . . . and the maintenance and enhancement of long-term productivity,” and (5) “any irreversible and irretrievable commitments of Federal resources.”²³ Collectively, the provisions of NEPA require an agency take a “hard look” at a project’s environmental impacts. This entails a robust examination of indirect and cumulative impacts, in addition to direct and site-specific impacts.²⁴

The Corps’ EIS must identify and fully consider all potential cumulative and/or indirect effects of the proposed mine as part of the NEPA process. The cumulative/indirect impacts analysis for each resource must:

• Evaluate the proposed project impacts along with all other past, present and reasonably foreseeable future projects and actions;
• Provide a quantified and detailed analysis of impacts from past, present and reasonably foreseeable future projects and actions;
• Describe the cumulative impacts assessment methodology and explain any assumptions and models used in the analysis;
• Identify the current condition of the resource as a baseline for determining cumulative impacts;
• Identify the trend in the condition of the resource as a measure of present impacts. (e.g., the health of the resource is improving, declining, or in stasis);
• Identify the future condition of the resource based on an analysis of the cumulative impacts of reasonably foreseeable projects or actions added to existing conditions and current trends (e.g., what will the future condition of the watershed be? Will the streams, wetlands, waterbodies, etc. provide similar habitat functions at similar levels to what is defined in the baseline? How will the aquatic ecosystem function?, etc.);
• Assess the cumulative impacts contribution of the proposed alternatives to the long-term health of the resource, and provide a specific measure for the projected impact from the proposed alternatives;
• Identify and evaluate the effectiveness of opportunities to avoid and minimize impacts, including working with other federal and State agencies, Tribal governments, local communities, Alaska Native organizations and entities, and regional and health non-profit organizations;
• Assess full build-out scenarios and associated impacts, including: where tailings from expansion can likely be placed, types of tailings dams (and increases in size to existing tailings dams) necessary to store future potentially acid-generating and non-acid generating tailings waste, tailings dam designs that address maximum credible earthquake and precipitation events, abilities for lining of increased tailings storage facilities, abilities to cap future tailings facilities, expansion of the pit, location and type of future mining, and associated infrastructure growth to accommodate mine expansion.

The EIS must also address the reasonably foreseeable increase in mining activity that could take advantage of the newly created infrastructure (e.g. Arctic Mine access road, Arctic Mine haul road, Ambler road). There are numerous other mining claims within the Ambler claim block, and additional mining claims at other locations along the proposed Ambler road route. The EIS must take a hard look at the cumulative impacts (including reasonably foreseeable future impacts) associated with these existing mining claims.

III. National Historic Preservation Act Section 106

The NHPA includes a “series of measures designed to encourage preservation of sites and structures of historic, architectural, or cultural significance.”²⁵ Section 106 of the NHPA requires that the “head of any federal agency” with authority over a proposed “undertaking” must, before approving it, “take into account the effect of the undertaking on any historic property,” give the Advisory Council on Historic Preservation (“ACHP”) a “reasonable opportunity to comment” on the proposed undertaking,²⁶ and “consult with any Indian tribe … that attaches religious and cultural significance” to potentially affected historic properties.²⁷ The goal of the NHPA Section 106 process is to “identify historic properties potentially affected by the undertaking, assess its effects and seek ways to avoid, minimize or mitigate any adverse effects on historic properties.”²⁸ NHPA Section 106 is a “‘stop, look, and listen’ provision that requires each federal agency to consider the effects of its programs” on historic properties.²⁹

The ACHP’s implementing regulations are set forth at 36 C.F.R. Part 800, and they are binding on all federal agencies. The ACHP regulations establish a four-step process through which federal agencies must fulfill their NHPA Section 106 obligations: (1) initiate the process where an undertaking has the potential to affect historic properties; (2) identify historic properties; (3) assess adverse effects on historic properties; and (4) resolve adverse effects.

During the first step, federal agencies must identify “consulting parties,” including the Alaska State Historic Preservation Officer (SHPO) and “any Indian tribes … that may attach religious and cultural significance to historic properties” potentially affected by the undertaking and initiate the consultation process.³⁰ The NHPA Section 106 process must be initiated early enough in the undertaking’s planning process that it can inform the development, evaluation, and selection of alternatives that avoid, minimize, or mitigate adverse effects on historic properties.³¹

Step two requires federal agencies to determine the undertaking’s APE and “take the steps necessary to identify historic properties” within the APE.³² APE refers to the “geographic area or areas within which an undertaking may directly or indirectly cause alterations in the character or use of historic properties,” and it is “influenced by the scale and nature of an undertaking and may be different for different kinds of effects caused by the undertaking.”³³ An “historic property” is “any prehistoric or historic district, site, building, structure, or object included in, or eligible for inclusion in the National Register.”³⁴ Historic properties “include[] properties of traditional religious and cultural importance to an Indian tribe … that meet the National Register criteria.”³⁵ Properties of traditional religious and cultural importance are often referred to as TCPs or cultural landscapes. A TCP is a property “eligible for inclusion in the National Register because of its association with cultural practices and beliefs of a living community that (a) are rooted in that community’s history, and (b) are important in maintaining the continued cultural identity of the community.”³⁶ A cultural landscape is a property encompassing a “geographic area including both cultural and natural resources and wildlife or domestic animals therein, associated with an historic event, activity, or person exhibiting other cultural or aesthetic values.”³⁷ Both TCPs and cultural landscapes are among the historic properties that must be considered by federal agencies during the NHPA Section 106 process.³⁸ “Eligible for inclusion” includes “both properties formally determined as such in accordance with [36 C.F.R. Part 63] and all other properties that meet the National Register criteria.”³⁹ Agencies must “make a reasonable and good faith effort to carry out appropriate identification efforts.”⁴⁰ Such efforts “may include background research, consultation, oral history interviews, sample field investigation, and field survey.”⁴¹ In addition to identifying historic properties previously listed on, or determined eligible for inclusion on, the National Register, agencies must “apply the National Register criteria … to properties identified within the [APE] that have not been previously evaluated for National Register eligibility.”⁴² In applying the National Register criteria, agencies must “acknowledge that Indian tribes … possess special expertise in assessing the eligibility of historic properties that may possess religious and cultural significance to them.”⁴³

Step three requires federal agencies to “apply the criteria of adverse effect to historic properties within the [APE].”⁴⁴ This means agencies must “assess the effects of the undertaking” on historic properties within the APE and “determine whether the effect will be adverse.”⁴⁵ An undertaking causes adverse effects if it “may alter, directly or indirectly, any of the characteristics of the historic property that qualify the property for inclusion in the National Register in any manner that would diminish the integrity of the property’s location, setting, materials, workmanship, feeling, or association.”⁴⁶ Adverse effects do not need to physically alter an historic property to be direct. Direct “refers to the causality, and not the physicality, of the effect.”⁴⁷ Accordingly, “if the effect comes from the undertaking at the same time and place with no intervening cause, it is ‘direct’ regardless of its specific type (e.g., whether it is visual, physical, auditory, etc.).”⁴⁸ Additionally, adverse effects include “reasonably foreseeable effects caused by the undertaking that may occur later in time, be farther removed in distance or be cumulative.”⁴⁹ Examples of adverse effects include without limitation: (a) “[p]hysical destruction of or damage to all or part of the property;” (b) “[c]hange of the character of the property’s use or of physical features within the property’s setting that contribute to its historic significance;” (c) “[i]ntroduction of visual, atmospheric or audible elements that diminish the integrity of the property’s significant historic features;” and (d) “[t]ransfer, lease, or sale of property out of Federal ownership or control without adequate and legally enforceable restrictions or conditions to ensure long-term preservation of the property’s historic significance.”⁵⁰

Step four requires federal agencies to “develop and evaluate modifications to the undertaking that could avoid, minimize, or mitigate adverse effects on historic properties.”⁵¹

Consultation is the most important aspect of the NHPA Section 106 process and must occur at every step. Consultation is the “process of seeking, discussing, and considering the views of other participants, and, where feasible, seeking agreement with them regarding matters arising in the section 106 process.”⁵² As noted above, federal agencies must “consult with any Indian tribe … that attaches religious and cultural significance to historic properties that may be affected by the undertaking.”⁵³ They must consult with Tribes at specific points about specific determinations during each step of the NHPA Section 106 process.⁵⁴ Consultation “should commence early in the planning process,” and Tribes must have a “reasonable opportunity to identify [their] concerns about historic properties, advise on the identification and evaluation of historic properties, including those of traditional religious and cultural importance, articulate [their] views on such properties, and participate in the resolution of adverse effects.”⁵⁵ Throughout consultation, federal agencies must grant Tribes “special consideration.”⁵⁶ Consultation with Tribes is “not an empty formality,”⁵⁷ and cannot be satisfied by “mere pro forma recitals,” “professions of good intent,” and “solicitations to consult.”⁵⁸ Instead, consultation “must recognize the government-to-government relationship” between the federal government and Tribes, and it should be conducted in a manner “respectful of tribal sovereignty” and “sensitive to the concerns and needs” of the Tribes.⁵⁹

The proposed mine and associated infrastructure have the potential to affect historic properties and cultural resources. This may result from a wide range of activities, including ground disturbance associated with mining, road construction, and construction of permanent facilities. The Corps must consult as part of this process and fully comply with the requirements in the NHPA to determine how proposed activities could impact historic properties listed on, or eligible for inclusion in, the National Register of Historic Places. Before completing the draft EIS, the Corps must ensure that an APE broad enough to encompass all potential direct and indirect effects has been established, which should be at least two miles in all directions from the proposed mine site to account for visual, noise, pollution, and other far-reaching impacts. The Corps must also ensure that all lands within the APE have been subject to a reasonable and good faith inquiry to identify historic properties, including adequate archaeological surveys to identify artifacts and other discrete resources as well as adequate ethnological investigations (including interviews of Tribal experts) to identify TCPs and cultural landscapes in the region, including traditional harvesting areas, traditional travel routes, sacred sites, and other elements. The Corps must also ensure that the criteria of adverse effect is properly applied and that adverse effects are appropriately mitigated and resolved, all in consultation with affected Tribes, the Alaska SHPO, and other consulting parties.

DISCUSSION

I. The EIS Must Consider Impacts from the Construction and Operation of the Ambler Road.

As noted, the proposed mine is closely related to the Ambler road, and by all accounts the mine’s economic feasibility depends on the eventual completion of the road. As such, the EIS should consider the Ambler road and mining-related use of that road as a connected action. At the very least, the EIS must consider the cumulative impacts of the proposed mine in combination with the Ambler road.

According to the project’s feasibility study, the Ambler road will serve as the primary access route for the mine. The mine will therefore depend on the Ambler road for integral aspects of its operations, including worker transport, material delivery (including fuel for the diesel-powered electrical facility), equipment delivery, and transport of mine products to market.⁶⁰ Without the road, Ambler Metals would, in all likelihood, lack an economically feasible means of access. Indeed, According to the feasibility study, “the Project assumes that the [Ambler] road will be constructed,”⁶¹ and without the road, there is a substantial risk to the project’s viability.⁶² The feasibility study even suggests that the project could be imperiled if toll rates for the proposed road are too high.⁶³

In addition, AIDEA has repeatedly stated that the purpose of the Ambler road is to serve as a gateway for development to the District. The purpose and need for the Ambler road project only further reinforces the fact that the road needs to be considered as a connected action. The Revised Permit Application for the Ambler Road states that “[t]he purpose of this project is to provide transportation access to the Ambler Mining District to support and encourage mineral exploration and development in this highly mineralized area.”⁶⁴ The clear purpose of this industrial road is to facilitate mine development.

AIDEA’s revised permit application for the Ambler Road states that “[t]he road would provide year-round surface transportation access to the Ambler Mining District to allow for expanded exploration, mine development, and mine operations at mineral prospects throughout the area.”⁶⁵ AIDEA also acknowledges in its application that mining in the Ambler district cannot or will not proceed unless this road is built, making it abundantly clear that the mine and the road are connected actions. As Rick Van Nieuwenhuyse, chief executive of Trilogy Metals, succinctly stated, “You build a road, you’ve got a mine.”⁶⁶ More recently, AIDEA provided $25,000 in funds to the villages of Ambler, Shungnak, and Kobuk—the communities that would be most impacted by the proposed mine—from an agency account dedicated to development of the road.⁶⁷ The Corps must fully consider the impacts and infrastructure associated with development of the Ambler road as part of its EIS.

The Corps must also consider the direct impacts on the Dalton Highway, other Alaska roads and communities, and wildlife potentially affected by ore export. Because ore leaving the Arctic Mine will travel down the Dalton Highway and other roads via truck, there will be impacts on those roads and nearby residents and wildlife that must be assessed. These impacts include the cost to the State of road damage through additional use, particulate and gaseous emissions’ effects on surrounding vegetation, waters, habitats, and communities, the adverse effects of ore and mining-related chemical and fuel spills, and the impacts of additional road noise on nearby residents and wildlife.

II. The Corps Must Identify and Protect All Jurisdictional Waters.

The Corps must conduct a full jurisdictional determination to ensure that all impacts to waters of the United States (WOTUS) are accounted for. The Corps should not rely solely on Ambler Metals’ data, and it should independently verify any information it receives from the company. The Corps should also conduct site-specific field verification of surface-water connectivity. All surveys, maps, and other information used in the Corps’ jurisdictional determination should be made publicly available. The Corps must include all jurisdictional waters, and must not arbitrarily limit the scope of its determination. For example, the Corps may not categorically exclude seasonally flooded wetlands or seasonally variable streams, both of which may be jurisdictional under the U.S. Supreme Court’s decision in Sackett v. EPA.⁶⁸

III. The EIS Must Address Compliance with the 404(b)(1) Guidelines.

Pursuant to the Clean Water Act Section 404(b)(1) Guidelines, no discharge of dredged or fill material shall be permitted if, among other things, a practicable alternative to the proposed discharge would have less adverse impact on the aquatic ecosystem.⁶⁹ The Corps also cannot authorize any discharge of dredged or fill material that will cause or contribute to significant degradation of the waters of the United States.⁷⁰

A. The Corps Cannot Approve the Permit if it Would Cause Significant Degradation.

The “degradation or destruction of special aquatic sites, such as filling operations in wetlands, is considered to be among the most severe environmental impacts covered by the[] Guidelines.”⁷¹

Under the 404(b)(1) guidelines, the Corps is required to consider the following effects, individually and collectively, that contribute to significant degradation:

(1) Significantly adverse effects of the discharge of pollutants on human health or welfare, including but not limited to effects on municipal water supplies, plankton, fish, shellfish, wildlife, and special aquatic sites;

(2) Significantly adverse effects of the discharge of pollutants on life stages of aquatic life and other wildlife dependent on aquatic ecosystems, including the transfer, concentration, and spread of pollutants or their byproducts outside of the disposal site through biological, physical, and chemical processes;

(3) Significantly adverse effects of the discharge of pollutants on aquatic ecosystem diversity, productivity, and stability. Such effects may include, but are not limited to, loss of fish and wildlife habitat or loss of the capacity of a wetland to assimilate nutrients, purify water, or reduce wave energy; or

(4) Significantly adverse effects of discharge of pollutants on recreational, aesthetic, and economic values.⁷²

The Corps is required to base this determination on factual determinations, evaluations, and tests required under the Guidelines, and to focus in particular on the persistence and permanence of the effects.⁷³ The Guidelines require the Corps to make certain factual determinations addressing the potential short-term or long-term effects of a proposed discharge of dredged or fill material on the physical, chemical, and biological components of the aquatic environment.⁷⁴ This includes determinations on:

a) physical substrate; b) water circulation, fluctuation, and salinity; c) suspended particulate/turbidity; d) contaminants; e) aquatic ecosystems and organisms; f) proposed disposal sites; g) cumulative effects on the aquatic ecosystem; and h) secondary effects on the aquatic ecosystem.

The Corps cannot authorize a discharge without “sufficient information to make a reasonable judgment as to whether the proposed discharge will comply with [the Section 404(b)(1)] Guidelines.”⁷⁵ “Sufficient information” includes the site-specific data necessary to make all determinations listed above.

Significant degradation is likely here because stream and wetland habitats would be lost within and upstream of the mine footprint. Upstream and downstream habitat would be degraded by the loss of the headwater streams and wetlands. Streams under or upstream of the mine footprint would be inaccessible by fish from downstream reaches because of: (1) elimination of streams and wetlands within the mine footprint either due to removal or burial under tailings and waste-rock facilities; (2) mine-pit dewatering and resultant capture of stream flows; (3) blockages that prevent fish passage. Loss of headwater streams has been shown to have impacts on fishes and their habitats in downstream mainstream reaches. In addition, streamflow alteration can lead to the loss of ecosystem structure and function, which constitutes significant degradation of the aquatic environment.

The EIS must identify the unknowns and evaluate the direct, indirect, and cumulative effects of loss of streams and wetlands on the environment at both the regional and local (site-specific) scale. If the EIS is unable to answer these questions, the Corps cannot make a finding that the project will not cause or contribute to significant degradation of the aquatic environment.

B. The Corps Must Select the Least Environmentally Damaging Practicable Alternative

When a project is not “water dependent,” as in the case of the mine, and the project would fill “special aquatic sites,” including wetlands, the Corps’ regulations create a rebuttable presumption that there are practicable and environmentally preferable alternatives, and such alternatives are presumed to have less adverse impact unless “clearly demonstrated” otherwise.⁷⁶ This substantive requirement mandates the Corps to select the least environmentally damaging practicable alternative (LEDPA).

An alternative is practicable “if it is available and capable of being done after taking into consideration cost, existing technology, and logistics in light of overall project purposes.”⁷⁷ Practicable alternatives include “activities which do not involve a discharge of dredged or fill material,” as well as “discharges of dredged or fill material at other locations” where such discharges would result in fewer impacts to the aquatic environment.⁷⁸ The applicant has the burden of demonstrating that no feasible alternative exists, and the Corps must engage in a reasoned analysis of this issue.⁷⁹ The Corps cannot blindly and uncritically accept an applicant’s study of alternatives and its assertions that no practicable alternative exists.⁸⁰ Under the regulations, any “practicable” alternative to achieve the basic and overall project purposes must be determined to be cost-effective, when viewed from the perspective of the industry as a whole. But the least environmentally damaging practicable alternative need not be the least costly, nor the most profitable.⁸¹ The regulations presume that less environmentally damaging alternatives are available to the applicant and practicable, unless the applicant clearly demonstrates otherwise. In the absence of such a clear showing, the Corps is required to deny the permit application.⁸²

Pursuant to this mandate, as well as NEPA, the EIS must examine a range of reasonable alternatives, including a “no action” alternative. The range of alternatives should not be constrained by the applicant’s desire to maximize the profitability of the mine, but should instead explore all available means of minimizing the projects impacts to wetlands, fish, wildlife, subsistence, and human health and welfare. If no feasible alternative adequately avoids or minimizes adverse environmental impacts to this largely undeveloped and remote region of Alaska, the Corps should select the “no action” alternative and deny the permit.

C. The Corps Should Require Compensatory Mitigation for any Unavoidable Impacts

The 404(b)(1) Guidelines provide that “no discharge of dredged or fill material shall be permitted unless appropriate and practicable steps have been taken which will minimize potential adverse impacts of the discharge on the aquatic ecosystem.”⁸³ Pursuant to the Corps’ permitting regulations, compensatory mitigation may be required to ensure that a permit complies with the 404(b)(1) Guidelines.⁸⁴

The Corps’ 2008 Mitigation Rule sets out how mitigation requirements are determined and provides the Corps with the authority to deny a permit if there is a “lack of appropriate and practicable compensatory mitigation.”⁸⁵ The 2008 Mitigation Rule also contains substantive provisions regarding the size and location of compensatory mitigation projects that are directly pertinent to the Corps’ decision whether to permit this project.⁸⁶

The Corps should not blindly accept representations from Ambler Metals that no compensatory mitigation is required. A determination that compensatory mitigation is not appropriate must be adequately supported.Accordingly, the EIS should address how alternatives will (1) avoid, (2) minimize, and (3) mitigate, in that order. The EIS must evaluate the effectiveness of mitigation measures. Further, it must identify how mitigation will replace lost aquatic resource functions. The Corps should work closely with the local communities and cooperating agencies to determine other mitigation measures to minimize impacts. The Corps should not solely rely on proposed avoidance and design criteria offered by Ambler Metals. The Corps should independently consider what additional measures are needed to avoid, minimize and mitigate impacts to wetlands and restore any lost aquatic habitat function.

The EIS should also provide a robust and transparent analysis of any proposed compensatory mitigation plan, evaluating effectiveness and detailing how that mitigation will replace lost aquatic resource functions. The compensatory mitigation must be based on the functional assessment of wetlands and aquatic resources. The mitigation must replace the lost functions according to an ecologically appropriate mitigation ratio. As the 2008 Compensatory Mitigation Rule states:

The fundamental objective of compensatory mitigation is to offset environmental losses resulting from unavoidable impacts to waters of the United States authorized by [Corps] permits. The district engineer must determine the compensatory mitigation . . . based on what is practicable and capable of compensating for the aquatic resource functions that will be lost as a result of the permitted activity.⁸⁷

Further, when mitigation is required to offset unavoidable impacts, “the amount of required mitigation must be, to the extent practicable, sufficient to replace lost aquatic resource functions.”⁸⁸

The Corps should coordinate closely with EPA and cooperating agencies in determining the appropriate calculation for impacted aquatic resources and associated mitigation credits. All compensatory mitigation options (from mitigation banks to in-lieu fee programs to permittee responsible mitigation) should be fully evaluated in the EIS. In addition to the comments above, the EIS should address the following:

• Require mitigation plans for each stage of the project (e.g. mitigation plans for pre-construction, construction, operations, maintenance, rehabilitation and closure);
• Assess mitigation needs, identify mitigation measures/commitments, best management practices, etc., and evaluate their effectiveness;
• Involve the Tribes and the public in mitigation planning, and ensure any mitigation plan includes the public in all monitoring measures;
• Assess likelihood of implementation and effectiveness of all proposed mitigation measures;
• Evaluate proposed timeframes for each mitigation measure;
• Evaluate whether proposed mitigation measures would result in additional environmental impacts;
• Assess any proposed adaptive management/corrective actions that would remedy failed mitigation or ineffective mitigation measures;
• Evaluate monitoring strategy for the project – how will goals and objectives of monitoring be assessed? How will data/information on monitoring be collected and reported (including a lists of measurement parameters, methods, locations, and frequency, etc.)?;
• Evaluate terms of measurable performance standards or expected outcomes;
• Assess whether performance expectations are clearly identified;
• Evaluate funding to implement mitigation and monitoring measures;
• Assess the resultant environmental effects; and
• Identify who is responsible for mitigation implementation and monitoring – lead agency, cooperating agency, project proponent, and third party.

IV. Impacts of Hardrock Mining

Generally, hardrock mining is associated with significant adverse environmental impacts including: removal of streams and wetlands; filling of streams and wetlands; alteration of streamflows; changes in water temperature; leaching of copper, zinc, and other heavy metals into streams and wetlands; acid mine drainage and acidification of receiving waters; spills of processing chemicals, fuel and other hazardous materials; fugitive dust emissions; sedimentation impacts to streams and wetlands; inhibition of fish passage; downstream siltation; tailings facility leaks and failures; and air pollution.

The Corps must consider the probability of fuel, chemical, ore, mine process water, concentrate, and other toxic or hazardous material spills at the mines. Spills of these materials must also be considered along the Ambler road route as well, since they would need to be transported via truck. Spills of process water, fuel, and other hazardous materials can result in chronic exposure to fish, invertebrates, and other aquatic organisms.

Risks associated with tailings facilities include, but are not limited to, water quality issues, water treatment in perpetuity, catastrophic failure events, and releases of contaminated water. Tailings storage facility releases are known to occur and sufficiently frequent to cause toxicity to fish and other aquatic organisms.⁸⁹

A. Tailings Dam Failure

The Corps’ public notice provides very little information about the design of the tailings facility, and offers no detailed assurance that the tailings facility would adequately contain toxic materials during mine operations and following closure. This impedes detailed environmental analysis and meaningful public review.

Tailings dam failures for large mines are common and occur frequently.⁹⁰ The concern over the rise in tailings failures is supported by a number of reports and studies.

In 2015, a report titled The Risk, Public Liability & Economics of Tailings Storage Facility Failure, found that the rate of serious tailings dams failures is increasing; that the rate of failures is propelled by, not in spite of, modern mining practices; and that the cost of cleanup exceeds what mining companies can afford.⁹¹ The report concluded that regulators must “look beyond ‘mechanisms of failure’ to the fundamental financials of the miner, the mine, and mega trends that shape decisions and realities at the level of miner and individual mine.”⁹²

Tailings dams have a high rate of failure, occurring at a worldwide rate of roughly one failure every 8 months.⁹³ Alarmed over the frequency and size of tailings failures across the world, the United Nations Environmental Programme (UNEP) prepared a report titled Mine Tailings Storage: Safety is No Accident.⁹⁴ The report concluded that “the number of serious failures has increased, despite advances in the engineering knowledge that can prevent them.”⁹⁵ The report also noted that:

The challenge of safely storing mine waste is growing in scale and complexity. Over the last few decades, the tailings-to-ore ratio has been increasing, as mineral deposits with increasingly lower ore grades are mined (Mudd 2007). The fate of this increasing volume of waste is a major focus of the debate on the general sustainability of mining and the practicalities of storing ever-increasing quantities of tailings. This is a challenge that could be further complicated by the increased severity and occurrence of extreme weather events expected under climate change predictions (Franks et al. 2011).⁹⁶

In another 2017 report, In the Dark Shadow of the Supercycle Tailings Failure Risk & Public Liability Reach All Time Highs, the authors confirmed that the frequency of significant tailings failures is on the rise, as well as the severity of those failures. The report found:

It is irrefutable that the frequency and consequence of Very Serious Failures and of Serious Failures is continuing to increase at alarming rates, that the trend emerged and grew post 1990 and that it is in large part a consequence of conscious decisions made at the mine‐level to make up for fundamental mine and miner specific economic disadvantages viz. global economics.⁹⁷

The report draws a direct correlation between the economics of mining and tailings failure. It notes that ore production volume and the mining cost per metric ton of ore are key economic variables in high failure frequency and severity.⁹⁸ The report concludes that regulators are not adequately accounting for the economic viability of mines and that the current market pressures will lead to “higher than previously expected Serious and Very Serious Failures.”⁹⁹

A 2002 report, titled Tailings Impoundment Failures: Are Geotechnical Engineers Listening?, found:

Tailings impoundments are some of the largest man-made structures. The largest dam ever constructed is a tailings dam. Tailings impoundments are also one of the most technically challenging elements in geotechnical practice. … Mine tailings impoundment failures are occurring at relatively high rates. Worldwide, the mining industry has experienced several significant impoundment failures per year over the past 30 years. … Many of these failure events have resulted in massive damage, severe economic impact and, in several cases, loss of life. The rate of failure is approximately ten times that for water retention dams. … Tailings impoundments can have environmental “failure” while maintaining sufficient structural integrity (e.g. impacts to surface and ground waters). … Within the full spectrum of failure modes that have occurred at large tailings impoundments, static liquefaction is likely the most common, and at the same time likely the least understood. … Static liquefaction, and the resulting flowslide of liquefied tailings materials, is indeed a relatively common phenomenon among the more dramatic tailings impoundment failure case histories. Static liquefaction can be a result of slope instability issues alone, or can be triggered as a result of other mechanisms.¹⁰⁰

The report reviewed tailing failure cases across the world and found several trends. The trends include:

• Active impoundments are more susceptible to failure;
• Upstream construction method dams are more susceptible to liquefaction flow events; and
• For active impoundments, overtopping is cited as the primary failure mode in nearly half of the reviewed incidents.¹⁰¹

Notably, the report concludes that each and every failure was predictable.¹⁰² For all the cases in the past 30 years reviewed by the report, “[t]here was lack of design ability, poor stewardship (construction, operating or closure) or a combination of the two, in each and every case history.”¹⁰³ The failures have involved “elementary engineering issues and/or basic operating issues.”¹⁰⁴

This opinion is confirmed by the 2017 Supercycle Tailings Failure Risk report discussed above. That report found that “[v]irtually all Very Serious Failures in recorded history were preventable, either by better design or by better operational management.”¹⁰⁵ Citing Mt. Polley as an example, the report identifies that the company deviated from construction design.¹⁰⁶ One of the experts convened to an independent review panel of the Mt. Polley tailings failure noted:

Tailings dams are complex systems that have evolved over the years. They are also unforgiving systems, in terms of the number of things that have to go right. Their reliability is contingent on consistently flawless execution in planning, in subsurface investigation, in analysis and design, in construction quality, in operational diligence, in monitoring, in regulatory actions, and in risk management at every level. All of these activities are subject to human error.¹⁰⁷

The 2017 Supercycle Tailings Failure Risk report also notes that the Fundão dam failure in Brazil was due to both construction flaws and operational deviations.¹⁰⁸

The U.S. District Court for the District of Alaska recently ordered the Corps and the Bureau of Land Management to prepare a supplemental EIS (SEIS) analyzing the impacts or tailings dam failure in connection with the proposed Donlin gold project.¹⁰⁹ The SEIS, released in September of this year, found that a spill of even 27% of proposed Donlin facility’s total capacity would have catastrophic consequences, burying the nearby village of Crooked Creek in tailings, contaminating area with heavy metals for “over a century,” causing “generationally lower abundance” of fish in the Kuskokwim River, and adversely affecting land-based subsistence resources including blueberries and low-bush cranberries.¹¹⁰

The EIS must take a hard look at the direct, indirect and cumulative impacts associated with potential tailings dam failure. The EIS must assess:

• Tailings failure impacts to subsistence food and water resources;
• Worst-case scenario—catastrophic tailings dam failure analysis must assess failures that result in release of at least one-third of impounded tailings;
• Dynamic (rather than pseudostatic) analysis for potential dam failure under earthquake loading;¹¹¹
• The feasibility and effectiveness of all possible mitigation measures;
• Past tailings failures across the globe and evaluate the potential for a serious failure due to design or operational error;
• Whether the Arctic Mine’s undeclared and unsupported economic viability, in light of the findings in the Supercycle Tailings Failure Risk report, may lead to increased likelihood of tailings failures;
• The risk of tailings failure due to earthquakes and seismic instability;
• External erosion of the dam face;
• How the design will address slope instability and static failure;
• Foundational structure to support the dam;
• Draining designs and potential for failed decants;
• Potential for overtopping;
• Seepage problems that can lead to tailings failures;
• Ambler Metals’ operational plans and their ability to recognize and react to emerging problems;
• Whether the designs account for climate change, climate variability and extreme weather events, including, but not limited to: o increases in the frequency and extent of heavy rain and snow events o increased levels of acid mine drainage due to increased rates of oxidation of metal sulfides as a result of increased precipitation and/or temperatures; o increased risk of large-scale pollution incidents due to more extreme weather events; and o increased flooding events or spring melt; and
• The best available practices currently implemented at other mine sites, and whether such practices are adequate given the documented frequency of tailings dam failure.

B. Tailings Leaks

The EIS must assess the potential for tailings leaks from the potentially acid-generating tailings facility. For post-closure tailings storage, the EIS must assess:

• How Ambler Metals will prevent seepage and outflows from the tailings storage facility;
• How Ambler Metals can store tailings in perpetuity without any management (e.g. pumping, treatment, and/or discharge);
• Evaluate impacts of evapotranspiration on water level compared to tailings;
• Assess uncertainties with storage of tailings without management; and
• Assess the leaching potential for non-acid generating waste rock that is used to build embankments and leaches metals through natural weathering.

The EIS must also assess whether tailings leaks are more or less likely based on location of the tailings facility.

C. Acid Mine Drainage

The rocks within the Arctic Deposit have among the highest risk of Acid Mine Drainage, or AMD, of any type of ore. The targeted deposit is a “volcanogenic massive sulfide deposit.” Mining massive sulfide deposits such as this one creates a risk of acid rock drainage and mobilization of metals, particularly copper which has numerous negative impacts on fish.¹¹² Open-pit mining would expose the Shungnak River and downstream waters to AMD and other potentially serious contamination issues.

According to the project’s feasibility study, “[a]bout 75% of samples were classified as potentially acid generating (PAG),” and “[a]ll of the kinetic samples … have the potential to generate acid.”¹¹³ Moreover, the feasibility study anticipates that “there will be no separation of waste based on acid generation potential.”¹¹⁴

The EIS must take a hard look at the likelihood of acid-rock drainage (ARD) problems. Any mitigation efforts must be carefully evaluated to determine the potential effectiveness and risks if those measures prove ineffective. Further, the EIS must consider other mines’ track records when it comes to controlling ARD.

1. Conduct Site Analogs

The geology and geochemistry of the project area may be unique or may exhibit similar features and characteristics as other copper, zinc, and lead mines in the State of Alaska, Canada and elsewhere in the United States. Site analogs allow for comparison and evaluation of acid mine drainage and metal leaching potential, and can be used to predict future site conditions. The EIS should include information regarding other historic and/or present copper/zinc/lead mining projects and claims as a basis of comparing the environmental effects of the proposed project.

The EIS should

• Discuss the regional mineralization and existing copper, zinc, and lead deposits and mine projects in Alaska, Canada and the lower-48 as site analogs for evaluating the proposed project geology and geochemistry; and
• Compare the ore, waste rock, and tailings characterization (e.g., chemical/physical composition, metals leachability and acid-generating potential) of the proposed project mine site to other existing mines in Alaska, Canada and the lower-48.

2. Mine Site Characterization

To evaluate the effects of acid rock drainage/metal leaching, the geology and geochemistry of the mine site should be fully characterized. There is a potential for acid rock drainage/metal leaching to occur from surface runoff and from the ore, waste rock facility, and infiltration/seepage from the tailings storage facility. The EIS should include a characterization of the ore, waste rock, and mine tailings for potential acid rock drainage/metal leaching. The EIS should:

• Characterize the ore and waste rock, and tailings, including the chemical/physical composition, metals leachability, and acid-generating potential;
• Evaluate Ambler Metals’ acid rock drainage and metal leaching testing plan;
• Asses alternative measures and options to minimize the release of acid rock drainage/metal leaching;
• Evaluate and model potential rates and volumes of infiltration/seepage from mining facilities into groundwater and surface waters;
• Identify the constituents and pollutants in the infiltration/seepage stream;
• Evaluate how unintended and/or unmitigated releases of seepage from facilities would affect surface/groundwater quality;
• Assess the effectiveness of any proposed measures to prevent or mitigate ARD;
• Evaluate Ambler Metals’ proposed monitoring plans to test for acid rock drainage/metal leaching in the adjacent groundwater and surface waters; and
• Assess Ambler’s plans to treat water impacted by acid rock drainage/metal leaching.

D. Toxic Materials and Waste

The hardrock mining industry is the single largest source of toxic waste and one of the most destructive industries in the country. Today’s industrial-strength mining involves the blasting, excavating, and crushing of many thousands of acres of land and the use of huge quantities of toxic chemicals such as cyanide and sulfuric acid. The mines that produce our copper, zinc, lead, gold, and silver are notorious for polluting adjacent streams, lakes, and groundwater with toxic by-products. The Environmental Protection Agency estimates that 40 percent of the watersheds in the western United States are contaminated by pollution from hardrock mines.

The EIS should:

• Describe and evaluate Ambler Metals’ chemical management plans to ensure safe usage, storage, and transport of all toxic chemicals;
• Assess potential ammonia and nitrate contamination from blasting activities;
• Analyze potential effects of contaminants and toxins in the airshed on the ecosystem, drinking water supply, and subsistence resources;
• Analyze the potential for aerial contaminants, either allowed or accidental for aquatic and terrestrial habitats, including many other resources, such as berry harvest areas, lichen and upland tundra, and inland forest resources;
• Analyze potential impacts to aquatic organisms important to the food chain and ecosystem functioning; and
• Analyze impacts to wildlife, including birds. Contaminants may impact birds indirectly through their food sources or directly through contact with toxic pit or tailings facility water or spills, or could affect egg laying and nesting success.

1. Flotation

Ambler Metals fails to provide descriptions of the specific chemicals it plans to use as processing reagents, but flotation methods are commonly employed in the processing of copper, lead, and zinc ores. It is likely different reagents would be necessary for each target mineral or flotation cycle. Ambler Metals must provide a complete list of process chemicals (by manufacturer), as well as the amount used for each cycle. The EIS must assess the direct, indirect and cumulative impacts associated with all potential processing reagents for each processing method. The EIS also need to provide details regarding the volume and weight of processing reagents and how they will be transported (e.g. how many truck, barge, and rail trips are required to move reagents) and stored at transfer points.

2. Cyanide

The mining industry has a long history of cyanide use.¹¹⁵ For decades, cyanide has been used as a pyrite depressant in base metal flotation.¹¹⁶ It has also been used for over a century for gold extraction.¹¹⁷ Cyanide-contaminated solution in tailing ponds and solution retention basins has proven to be attractive to unsuspecting waterfowl and wildlife.¹¹⁸ These organisms have suffered both acute and chronic poisoning as a result of direct contact with and ingestion of cyanide-contaminated solution.¹¹⁹ Leakage from processing facilities can allow the release of cyanide and other toxic constituents directly into the environment.¹²⁰ Residual cyanide in mine tailings can cause persistent release of toxic metals (e.g., mercury) into groundwater and surface waters.

Accidental spills of cyanide at mine processing facilities do occur. For example, the Fort Knox Gold Mine north of Fairbanks had spill releases of 300,000 gallons of cyanide containing water (May 2010) and 45,000 gallons as a result of a bulldozer breaching the supply line (August 2012).¹²¹

The transportation, storage, and disposal of cyanide present potential risks and many opportunities for accidental spills and releases of cyanide. Cyanide released into the environment can adversely impact water, soil, aquatic organisms, wildlife, waterfowl, and humans.¹²² Potential spills of transported and stored cyanide should be evaluated.

The EIS should assess the environmental and human health impacts associated with cyanide exposure and strategies aimed at reducing exposure to humans and wildlife.

3. Mercury

The EIS should evaluate the geochemistry to determine whether there are any potential mercury issues. If there is mercury in the ore and tailings waste, the EIS should take a hard look at the direct, indirect and cumulative impacts. The EIS should:

• Quantify the potential amount of fugitive mercury emissions;
• Quantify cumulative levels of mercury in biota;
• Address climate change impacts and potentially for greater methylation;
• Assess potential impacts on fish, wildlife and people; and
• Assess human exposure from fish consumption.

4. Fuel Spills

The EIS should analyze the direct, indirect and cumulative impacts of fuel spills. Fuel spills can take place throughout the project area, from the mine site to the port. The fuel spill analysis should assess impacts on subsistence resources and users throughout the Shungnak and Kogoluktuk watersheds, including downstream from the mine and along the proposed Ambler Access Road route.

The EIS must address the likelihood and impacts of fuel spills on all resources at all locations. The EIS should evaluate Ambler Metals’ spill prevention and emergency response plans at all site locations. The EIS should analyze possible spill scenarios and responses based on the location of the spill.

5. Other Leaks, Spills and Use of Chemicals

Spills are a common occurrence at mine sites in Alaska and across the world.¹²³ A report by Earthworks, The Track Record of Environmental Impacts Resulting from Pipeline Spills, Accidental Releases and Failure to Capture and Treat Mine Impacted Water, U.S. Gold Mines Spills & Failures Report, evaluated gold mine toxic releases in the U.S.¹²⁴ The report found that 27 of 27 mining operations have experienced at least one pipeline spill or other accidental release.¹²⁵ 20 of the 27 mining operations have failed to capture or control contaminated seepage.¹²⁶ The report concluded that “mines with high acid generating potential and in close proximity to surface and groundwater are at highest risk for water quality impacts.¹²⁷ In a 2012 report, Earthworks compiled the record of pipeline, seepage control and tailings impoundment failures at operating copper porphyry mines in the U.S.¹²⁸ The report concluded that:

[W]ater quality impacts to surface and/or groundwater are common at currently operating copper porphyry mines in U.S., resulting from three failure modes (pipeline spills or other accidental releases, failure to capture and treat mine seepage, and tailings spills or impoundment failures).

These failures resulted in a variety of environmental impacts, such as contamination of drinking water aquifers, contamination and loss of fish and wildlife and their habitat, and risks to public health. In some cases, water quality impacts are so severe that acid mine drainage will generate water pollution in perpetuity.¹²⁹

Water quality impacts from pipeline spills, accidental releases, failure to capture and treat mine seepage, and tailings spills or impoundment failures should all be anticipated and fully evaluated in the EIS. The EIS must analyze the direct, indirect and cumulative impacts of toxic spills, leaks and accidental releases. The EIS should analyze the direct, indirect and cumulative impacts of pesticides, herbicides and de-icing compounds used for maintaining infrastructure. The EIS should also assess potential spill risk and impacts for reagents and concentrate spills.

V. Transportation Impacts

The EIS should address effects of haul roads, access roads, and transportation corridors—including use of the proposed Ambler Road—on fish, wildlife, and subsistence resources. The analysis should address:

• Changes in wildlife movement or migration patterns, including bisected wildlife migratory routes, displacement and habitat avoidance;
• Habitat fragmentation;
• Stream crossing impacts (e.g. culverts, bridges);
• Increased hunting pressure on wildlife from increased road access;
• Alternative alignments;
• Seasonal restrictions on construction;
• Location of material sources and analysis of gravel quarry impacts;
• Erosion, sedimentation and turbidity impacts from the road corridor;
• Toxic and contaminant impacts from vehicles on the road corridor (oil residue, oil spills, hydraulic fluids, heavy metals, salts, and organic molecules);
• Introduction of contaminants from bridges (lead, rust, chemicals from paints, solvents, abrasives and cleaners);
• Dust control measures and impacts from dust suppressants;
• Surface and groundwater hydrology, including alterations to stream flow and movement of water through wetlands;
• Hydrologic changes, including floodplain alterations;
• Backwater flooding;
• Roadbed liquefaction from hill-slope wetland fill; and
• Siting of proposed bridge crossings in locations with higher flow variability through alluvial materials.

In addition to those issues identified above, the EIS must address the indirect, cumulative and reasonably foreseeable impacts associated with road development.

VI. Reclamation, Long-Term Management, and Financial Assurances

A key component in determining the environmental impacts of a proposed mine is the effectiveness of closure and reclamation planning activities including long-term water management. The EIS must assess the financial assurances offered by Ambler Metals for post-closure reclamation and long-term water management. This is especially critical as the project Feasibility Study admits that “water treatment … will be required in perpetuity.”¹³⁰

The EIS should provide a detailed level of information to ensure that there will be adequate financial assurance to cover the costs of implementing closure and reclamation plans, monitoring, contingency measures, and long-term water management to avoid unacceptable adverse environmental impacts. Mine closure and post-closure water treatment costs can typically range from $10s to $100s of millions. The EIS should disclose the costs associated with implementing the closure and reclamation plan, as well as the contingency measures to address the reasonably foreseeable but not specifically predictable project outcomes. The financial assurances should be in a form that protects the public interest in the event that Ambler Metals, or any future companies involved in the operations at the mine, is unable to implement contingency measures or perform long-term operation and maintenance. Details regarding the financial assurances must be provided for public review and comment.

The EIS should:

• Assess and independently verify the cost (+/- percent) to reclaim and close the site in a manner that achieves reclamation goals and post-mining land use objectives;
• Discuss effectiveness for each criteria identified for determining success of reclamation activities for bond release;
• Assess and independently verify the direct costs for site reclamation, monitoring, long term management (including water treatment), maintenance, and contingencies, including removal of structures and facilities, and revegetation;
• Assess and independently verify the costs associated with implementing contingency measures to address reasonably foreseeable, but not specifically predicted, outcomes;
• Assess and independently verify the cost estimates (including reasonable contingencies) and appropriate economic variables to calculate the net present value of future expenses, including the time period needed to complete long term treatment, monitoring and maintenance;
• Address how financial assurance cost estimates will be re-evaluated periodically (e.g. every three to five years or whenever a major change to the mine operations has occurred);
• Identify all potentially responsible parties for any post-closure clean up actions, and evaluate their potential for meeting post-closure obligations — the financial assurance should not depend on the continued financial health of the mine operator or its parent companies;
• Disclose detailed information about the process used to develop and secure financial assurance, including, but not limited to, costs, calculations, models, assumptions, inflation adjustments and rates, rates of return, contingencies, labor rates, and net present value to consider costs many years into the future;
• Evaluate the benefits and costs of removal of the tailings material and potentially acid generating material off-site;
• Base the financial assurance estimates on the reasonable spill or failure scenarios, such as the largest disturbances and material volume, water treatment, soil amendments, and hazardous materials;
• Assess the costs of a worst-case post-closure water treatment scenario;
• Estimate the indirect costs, such as mobilization and demobilization, contingencies, engineering design, etc.;
• Evaluate the indirect and cumulative costs associated with the long-term impacts to subsistence and water resources; and
• Evaluate Ambler Metals, Trilogy, and South 32’s fiscal solvency in assessing all financial assurances.

VII. Wetlands and Aquatic Ecosystems

The proposed project will contribute to the direct loss or degradation of wetlands, aquatic resources, and riparian areas for the construction of permanent and temporary facilities. According to the Project Application, 120.71 acres of wetlands would be filled. The project will also fill headwater streams, and pit dewatering will have yet unquantified impacts. The EIS should quantify and disclose the direct, indirect, and cumulative wetland impacts associated with construction of the mine site, support facilities, and transportation corridor.

The EIS should:

• Describe the appropriate and practicable steps taken to avoid, minimize, and compensate for unavoidable impacts to wetlands, aquatic resources, and riparian areas. Alternatives should consider options for avoiding and minimizing wetland impacts;
• Characterize acreages, habitat types and quantify areas of wetlands and aquatic resources within the project area – include their location and information on aerial photograph maps;
• Describe and evaluate the effectiveness of mitigation measures/commitments to minimize the unavoidable impacts to wetlands;
• Develop a monitoring plan for wetlands, aquatic resources, and riparian areas to ensure implementation of mitigation measures and their effectiveness. The monitoring plan should also specify corrective measures and thresholds for action;
• Assess food web ecology and potential for interruption of trophic processes as a result of the Project;
• Evaluate aquatic species diversity and assemblages (e.g., potential effects of the Project on species diversity, shifts in competition, and change in species assemblages);
• Evaluate loss and degradation of total miles of stream channel habitat used by resident and anadromous fish;
• Assess impacts to aquatic macroinvertebrates in both stream and lake environments and evaluate indirect impacts of potential loss of macroinvertebrates to fish population sustainability;
• Include delineation of all wetlands potentially affected by the project and an assessment of wetland functional values;
• Assess existing natural streamflow variability, including the magnitude, frequency, timing, duration, rate of change, and predictability of streamflow events and the sequence of streamflow conditions, and how the project will direct and indirectly impact streamflow variability. The natural flow paradigm is crucial to maintaining healthy aquatic ecosystems;
• Evaluate loss of headwater streams from the mine footprint fill and associated impacts to the groundwater–surface water hydrology, nutrient processing, and export rates of resources and materials to downstream aquatic ecosystems; and
• Quantify the area of riparian floodplain wetland habitat that would either be lost or suffer substantial changes in hydrologic connectivity with streams because of reduced streamflow from the mine footprint and assess the direct, indirect and cumulative impacts to the aquatic ecosystem.

A. Water Quality

There will be both short- and long-term impacts to water quality resulting from the mine-site water impoundments and open-pit mining activities. The use of multiple petroleum products, large quantities of chemicals for milling processes, tailings impoundment, and erosion from heavy equipment operations will affect water chemistry, quality, and possibly quantity. There is a potential for metal release and acid generation from waste rock, tailings, and pit walls. A large open pit and dewatering will have impacts on nearby streams. Ambler Metals must provide the Corps with a Mine Waste Management Plan (included in its Water Management Plan) so the EIS can adequately assess and address potential impacts to water quality, including changes in groundwater chemistry from dewatering and mining related causes. This Mine Waste Management Plan should also include detailed hydrogeochemical models for managing water quality. The EIS should assess the post-closure water quality of the pit and associated direct, indirect and cumulative impacts. The EIS should also assess the risks of water flowing out of the pit into ground water and surface water and evaluate the potential impacts to ground and surface water quality.

B. Water Quantity/Water Balance

The mine site water balance should be estimated for each phase of the mine development (e.g., construction, operations, closure, reclamation periods, and post-closure), and cover a range of hydrological conditions (extreme and average) and potential variations or disruptions in process flow (e.g., temporary suspension of operations as well as closure). The mine site water balance should be described in detail in the EIS. The project’s Feasibility Study notes that “[a] trend of increasing hydraulic conductivity with depth appears to occur at this site. As the pit advances into later years and gets deeper, in-pit dewatering wells may be beneficial.”¹³¹ The EIS must:

• Characterize all potential water source(s) (e.g., surface water, ground water, snow, precipitation, run off, etc.) and estimate the amount of water from each source (including by basin);
• Specify the volume of water needed for construction and operation of the mine facility;
• Estimate peak flood flows, precipitation, and duration and intensity of storm events on a seasonal basis;
• Estimate changes in water flow patterns for surface drainage modifications, groundwater aquifer dewatering, surface water dewatering, water use, water storage and discharge, and for different seasons;
• Identify the location of meteorological stations and water monitoring stations, length of monitoring and data collection;
• Provide a detailed water balance evaluation at the mine facilities during the full lifecycle– water flow patterns for surface water, water use, land application and discharge systems, pond storage and discharge, seasonal changes, etc. during steady state and peak flow conditions;
• Evaluate tailings facility capacity to account for extreme precipitation during the rainy season, spring breakup/snow melt, and during high precipitation years;
• Evaluate the effectiveness of any proposed mitigation/emergency measures to address water management concerns;
• Evaluate extent (three-dimensional spatial extent) and impact of cone of depression, including assessing impact to groundwater flow pathways;
• Evaluate whether the cone of depression will accelerate flow toward the artificial gradient;
• Evaluate whether the cone of depression will create artificial bypass reaches;
• Assess level of connectivity between the proposed pit and nearby groundwater aquifers;
• Evaluate the potential for the project to restructure the head gradient of continuous aquifer networks;
• Evaluate the potential of dewatering to prolong drought in intermittent reaches;
• Assess how Ambler Metals plans to mimic spatial and temporal heterogeneity of water quantity and quality;
• Assess whether seeps, springs, and primary order streams will be bypassed (essentially eliminating the mosaic of headwater sources);
• Analyze impacts to surface seasonal water flow, including quality and quantity from construction and operation of the mine and transportation corridor, potential changes to hydrology of rivers and streams at crossings, scouring, erosion, and other impacts to geomorphology in the project area;
• Provide a detailed schematic diagram depicting the water balance changes throughout the mine life cycle—construction, start up, operations, closure, reclamation, and post-closure and monitoring;
• Include a water-resource analysis that evaluates all disturbances (e.g. surface hardening and soil compaction from roads, overall facility footprint, overburden removal, permafrost disturbance, etc.) that may influence water storage capacity and infiltration rates related to groundwater;
• Consider impacts from project water management on fish, wildlife, habitat, and subsistence resources;
• Assess extent of impacts from groundwater pumping and dewatering of streams and wetlands in the vicinity of the mine, which may affect fish spawning, rearing, and overwintering habitat, migratory birds and other animals;
• Identify and explicitly address shortcomings in precipitation and streamflow monitoring data, and evaluate how these uncertainties in the site water balance propagate through their mine water management plans; and
• Explicitly consider and discuss uncertainties in the site water balance related to incomplete data or short periods of record.

Groundwater recharge, discharge, and storage are complex, highly non-linear processes which require rigorous simulation of all processes from the ground surface to the water table, including flows within the unsaturated zone. To accurately capture such dynamics, the EIS needs to clearly show how the unsaturated zone will be simulated. However, to adequately characterize the impacts of mining, the EIS must treat groundwater and surface water as a coupled system using an integrated hydrologic model, rather than developing separate models that feed inputs/outputs to one another. The project’s Feasibility Study reveals heterogenous aquifer conditions, with the majority of groundwater flow in the mine area ultimately discharging to Subarctic Creek.¹³² It also acknowledges that “the planned facilities will be located in groundwater recharge zones.”¹³³

The EIS must consider groundwater-surface water interactions in detail. The EIS must assess the fully coupled flow and water quality within the system. The EIS must detail how extraction of groundwater, treatment of mine water, and discharge to surface water will affect critical habitat variables including stream discharge, stream temperature, pH, metals concentrations, and suspended sediment.

C. Water Treatment

The EIS should provide detailed information regarding the proposed water treatment and long-term treatment and monitoring for the proposed mine facility. This is critical because contact water from mining operations will be treated and discharged into the Shungnak River.¹³⁴ An effective water treatment system would ensure that impacts to the water quality of Subarctic Creek, the Shungnak River and other surface and groundwaters are minimized. The EIS should:

• Describe in detail the water treatment systems, type of filtration and removal system – active or passive, type of pollutants to be removed, and provide estimates of the mine effluent water quality (e.g., the type of pollutants and volume of water, etc.);
• Evaluate the effectiveness of the wastewater treatment measures (all water treatment options need to have proven efficacy on mine sites, and should have proven efficacy at the scale that has been proposed at the Arctic Mine);
• Provide a detailed schematic diagram depicting treatment schemes through mine construction, start up, operations, closure, reclamation, and post-closure and monitoring;
• Evaluate the effectiveness of the water treatment systems during seasonal and high flow events, and during pit dewatering;
• Identify back up options, as needed to address water management concerns throughout the mine lifecycle. For example: o During high water periods, can the excess water be managed or stored beyond the capacity of the proposed treatment system? o In predicting the water treatment capacity needs, does this account for climate change effects?
• Provide estimates of the quantities and composition of process solutions, tailings water, runoff waters, mine drainage, and treated effluent at the proposed operation;
• Assess the worst-case post-closure water treatment scenario;
• Assess the risks of leaching from the tailings and waste-rock facilities;
• Identify and evaluate specific protocols in a gray water disposal plan;
• Assess maximum treatment capacity on a daily basis; and
• Evaluate stormwater pollution prevention plans.

VIII. Fish

Subarctic Creek, the Shungnak River, and the Kogoluktuk River are pristine watersheds. Most of these streams provide habitat for resident fish species, and some provide habitat for anadromous fish as well. Despite being isolated from the Kobuk River by a large waterfall preventing migrations by anadromous fish, the Shungnak River drainage supports self-sustaining populations of Arctic grayling, Dolly Varden, round whitefish and slimy sculpin.¹³⁵ “According to Bradley (2017) it is likely the Dolly Varden move into the upper reaches of Subarctic Creek,” where the mine would be located, “to feed on the abundant aquatic insects.”¹³⁶ The EIS must also consider— in terms of both water quality and flow regime—the potential for impacts to downstream anadromous fisheries on which local subsistence-based communities depend, including salmon and Inconnu (sheefish).¹³⁷

Changes in water flow and water quality from the mine will impact fish habitat throughout the affected watersheds. The EIS must address several issues regarding fish habitat impacts. For instance, the EIS must identify which waterbodies will be filled, altered, or dewatered, and evaluate the impacts from the mine on all affected streams. The EIS must address, among other things, flow regimes, temperature regimes, sediment distribution, and habitat complexity and how these changes impact the shifting habitat mosaic which is essential to habitat quality and maintenance of the biocomplexity needed to sustain native fisheries and aquatic ecosystems. As discussed above, the EIS must address how and when surplus water from the mine will be discharged. And the EIS must evaluate how changes in flow, water quality, and other key ecosystem characteristics will affect the different life history stage of each affected fish species. The EIS should draw a clear distinction between impacts to fish production or populations, and impacts to fish habitat.

A. Copper Impacts on Fisheries

The Arctic deposit is primarily a copper ore body. Copper is a documented neurotoxin in fish, and impacts to resident and anadromous fisheries from increased copper concentrations are a significant risk from the project, with the potential to adversely affect productivity, biodiversity, and long-term sustainability. The EIS needs to take a hard look at the direct, indirect, and cumulative impacts of copper at both low and high concentrations, and address both acute and chronic toxicity. The EIS must also address whether the impacts from increased copper concentrations can be effectively mitigated.

This analysis does not end at determining whether water quality standards are met. The water quality standards are based on lethal doses and thus may not address sub-lethal effects. The EIS should incorporate site-specific testing using water sources and native fish species relevant to the project area to reduce uncertainty associated with estimating adverse effects levels of copper to fisheries. The EIS needs to ensure that all impacts to fish — including sub-lethal effects — are assessed and the mine is designed to ensure water that moves off site is high enough quality to have no sub-lethal or lethal impacts to aquatic life.

B. Essential Fish Habitat

The 1996 amendments to the Magnuson Fishery Conservation and Management Act added, among other provisions, 16 U.S.C. § 1855(b), which governs the conservation of essential fish habitat (EFH).¹³⁸ Under this provision, the Regional Fishery Management Councils established under 16 U.S.C. § 1852 must identify and describe EFH in their Fishery Management Plans.¹³⁹ EFH is defined as “those waters and substrate necessary to fish for spawning, breeding, feeding or growth to maturity.”¹⁴⁰ NOAA Fisheries is required to make information regarding EFH available in the form of maps, written descriptions, or both.¹⁴¹ Any federal agency whose actions, including permitting decisions, may adversely affect EFH must consult with NOAA Fisheries before acting.¹⁴² The EFH assessment must use the best scientific information available, and it must contain a description of the proposed action, an analysis of the potential adverse effects, the agency’s conclusion regarding the effects on EFH, and any proposed mitigation.¹⁴³ NOAA Fisheries will issue Conservation Recommendations based on the assessment prepared by the action agency.¹⁴⁴ The EFH consultation and resulting Conservation Recommendations should be combined with the NEPA review and included in the draft EIS.¹⁴⁵

The EIS must take a hard look at the direct, indirect and cumulative impacts to EFH, including degradation and contamination of EFH that would adversely impact fisheries at any of the various life stages.

IX. Road Corridors & Culverts

Roads constructed through streams significantly impede or may altogether block fish movements. If properly sized, installed, monitored, and maintained, culverts can potentially mitigate the impacts of roads on stream crossings. However, culverts do not address many of the other hydrologic impacts of road construction, and just one ineffective culvert can restrict access to key seasonal habitat and thus impact a whole fish population. Culvert failure is common, with significant percentages of culverts found to be inadequate for fish passage in Alaska.¹⁴⁶ Culvert failure negatively impacts waterways and fish habitat. Moreover, the physical barrier imposed can significantly alter hydrology and intercepts natural water flow, which is a driver of connectivity for fish.

The transportation corridor for the project as proposed includes numerous culverts. This raises significant concerns regarding impacts to fish passage. The EIS must take a hard look at the direct, indirect and cumulative impacts of culvert failure and associated impacts on fish passage.

In addition to concerns over culvert failure, the EIS must also assess culvert placement over time. The current proposed project has a 13-year life, although with expansion or the development of other deposits in the Ambler claims block this may be much longer. As with any stream crossing, this presents a challenge because streams move over time, depending upon their flow and sediment regimes and the compositions of their beds, floodplains, and banks. Those that are more alluvial in nature actively aggrade and denude their courses, meander about their floodplains, and erode their banks. Even when culverts appear adequately sized, alluvial streams can be laterally dynamic enough to cause significant erosion, making the culvert position obsolete and improperly placed to accommodate the patterns in flow resulting from natural changes that have occurred upstream. Removing and replacing culverts would have serious adverse effects on the affected waterbodies. The impacts of any changes to these or other structures during the various phases of the project must be fully analyzed in the EIS.

In addition to these concerns the EIS should address:

• Impacts to streams and wetlands from culvert failure during flood events;
• Icing and development of aufeis;
• Changes to stream flow (accelerated velocities) and associated erosion;
• Fill in floodplains that could impede passage of juveniles that utilize flooded habitats on a seasonal basis for feeding;

X. Wildlife Impacts

The Corps must take a hard look at the direct, indirect and cumulative impacts to wildlife and wildlife habitat. The proposed mine and its associated transportation infrastructure (including frequent use of the proposed Ambler Road) will have direct and indirect impacts on wildlife that need to be considered in the EIS. Direct impacts can be broadly classified as disturbance (behavioral change) or displacement (avoidance of a previously used area). Indirect impacts include habitat alteration or changes in food abundance. The mine and associated mine operations will also result in disturbance and displacement. The EIS should address noise impacts (from blasting, construction, vehicles, helicopters, airplanes, etc.) on wildlife, including displacement and avoidance.

A. Caribou

The Corps needs to consider the full range of potentially serious impacts that the project—on its own and in combination with the Ambler road—could have on the migratory behavior, habitat, health, and abundance of the Western Arctic Caribou Herd (WAH).

Caribou herds, and specifically barren-ground caribou herds, have been declining globally.¹⁴⁷ Global declines have exceeded 50% for migrating caribou with some herds declining more than 90%.¹⁴⁸ Several herds show no signs of recovery and remain at record low numbers.¹⁴⁹ Alaska is the only part of the United States that retains caribou herds.¹⁵⁰ The Alaska herds have also suffered similar declines.¹⁵¹

The WAH is the herd that will overlap with and be impacted by the proposed mine. The Western Arctic Herd migrates through and/or winters in the area of the proposed mine. The WAH was previously the largest caribou herd in Alaska, with a population high of 490,000 individuals in 2003.¹⁵² Over the last two decades, however, the WAH has severely declined to about 121,000 animals; a 75% decline in the population.¹⁵³

[IMAGE PLACEHOLDER: Population size over time for the four North Slope caribou herds in Alaska.]

Population size over time for the four North Slope caribou herds in Alaska. WAH = Western Arctic Herd, TCH = Teshekpuk Caribou Herd, CAH = Central Arctic Herd, PCH = Porcupine Caribou Herd.

Barren-ground caribou herds, like the WAH, “are renowned for their long-distance migrations, covering hundreds to thousands of kilometers each year in some of the longest overland movements in the world.”¹⁵⁴ Mining development and associated road networks can act as barriers to migration.¹⁵⁵ Even if animals are eventually able to cross these barriers, they may expend more energy because of these barriers then they otherwise would.¹⁵⁶ These higher energy expenditures also negatively affect caribou.

Anthropogenic development and associated roads cause behavior changes in caribou.¹⁵⁷ Pregnant females and those with young calves are far less likely to cross developed areas or roads, tending instead to avoid them completely.¹⁵⁸ Further, migrating caribou have been shown to avoid roads by remarkable distances: 16-17 km (over 10 miles) prior to crossing and 3 km (nearly 2 miles) after crossing.¹⁵⁹ Displacement from the habitats in these road corridors can cause the animals to select lower quality foraging areas, causing further declines in fitness.¹⁶⁰

Winter is a critical time for caribou. Foraging opportunities are limited and pregnant females as well as their offspring are particularly at risk during this period.¹⁶¹ Any displacement or habitat alteration that caribou experience during the winter season may carry a higher energy cost than other seasons.¹⁶² This is even more pronounced in especially severe winters, increasing the likelihood of death or reproductive failure, which negatively impact population growth.¹⁶³ Even if the animals survive, the additional burden placed on their movements and energy expenditures during the winter season can persist into later years.¹⁶⁴

Additionally, habitat loss resulting from mine development and associated roads is not limited to just the footprint of the project. Caribou overwhelmingly avoid developed areas, with 50-95% of the herd reducing their use of areas with 5 km (over 3 miles) of developed areas.¹⁶⁵ Further, caribou do not habituate (eventually grow accustomed to) anthropogenic development.¹⁶⁶ Rather, the animals perpetually avoid developed areas by distances of 4-10 km, particularly development where some level of human activity remains.¹⁶⁷ Thus, it is not just the footprint of the development that represents habitat loss but indeed a much larger zone around the development.

Mining development and associated roads also result in dust and toxic metal deposition on forage around roads, which can reduce the forage quality for caribou or even cause the animals to consume toxic heavy metals.¹⁶⁸ For example, dust deposition has been found to extend up to 1 km from active roads, which in turn lead to a reduction in lichen (a prominent forage species for caribou) in the same area.¹⁶⁹ This dust deposition can further alter soil pH, plant community composition, permafrost thaw depth, plant nutritional quality, and soil moisture and temperature.¹⁷⁰ Airborne heavy metals may spread much farther than 1 km from active roadways.¹⁷¹ Further, dust from roadways can cause early snow melt, which in turn causes the heavy metals in that dust to spread farther into the surrounding environment.¹⁷² “Young organisms, especially those that are still feeding on milk, experience greater absorption and lower excretion of toxic metals, making early age a critical period for metal toxicity.”¹⁷³

Climate change will likely compound the pressures on caribou.¹⁷⁴ Climate change has been affecting the Arctic at nearly twice the rate of the global average.¹⁷⁵ Climate change is leading to increased freeze/thaw events, and extensive ice cover can reduce forage availability causing mass starvation events.¹⁷⁶ Longer ice-free periods on rivers and lakes could also further hinder migration, resulting in even higher migration energy losses.¹⁷⁷ Climate change is also expected to both elongate the timeframe that caribou are exposed to parasites and pathogens and increase the number of parasites and pathogens they are exposed to.¹⁷⁸

Each of the above points must be considered in combination. In isolation, each of these effects takes a toll on caribou populations. But these effects do not happen in isolation. Rather, they happen in tandem and synergize in their impacts. Therefore, a full analysis must consider these impacts in combination. Lastly, a full analysis must consider the cumulative effects of the proposed mine, including the Ambler road, as well as the effects of the many other mines that are expected to be developed within the Ambler mining district as well as along the Ambler road corridor. The EIS must also consider cumulative impacts to the WAH from streamlined oil and gas permitting in the NPR-A, including in parts of the WAH calving grounds.

B. Birds

The EIS should address impacts on both bald and golden eagles, which are protected under the Bald and Golden Eagle Protection Act. Eagle take permits may be necessary for activities that result in removal of nests, loss of habitat, and disturbance of birds during construction, operation, and maintenance of the project. The EIS should identify the presence of eagles or their nests in the project area, and analyze potential impacts of the proposed project.

The EIS should address presence and potential impacts of the project on all migratory birds protected under the Migratory Bird Treaty Act with flyways in proximity to the project. The EIS should identify all birds of conservation concern and bird concentrations. There are a variety of potential impacts that the EIS should address:

• Blasting and explosive use. The magnitude and timing of explosive use could disturb birds using the area, particularly during the breeding season;
• Vegetation clearing;
• Water impoundments;
• Potential risk of bird strikes with towers, power transmission lines, or other above ground infrastructure;
• Collision potentials;
• Spills of fuel or other toxic substances (e.g., mine tailings, process water);
• Impacts to protected species.

The EIS should provide abundance, distribution, and trend information for all bird species in the project area. The EIS should also identify all potential habitat that is suitable for breeding, nesting, roosting, staging, foraging, and address loss of such habitat. The EIS should identify and evaluate the effectiveness of any proposed mitigation and minimization efforts including seasonal timing restrictions.

C. Brown Bears

The Arctic mine and associated infrastructure may adversely impact brown bears. The EIS must consider the direct, indirect and cumulative impacts of the project on brown bear populations in the Brooks Range.

Brown bears have large area requirements and home ranges in Alaska vary from 10 to 50 square miles on the northern islands of Southeast Alaska to over 1,000 square miles on Alaska’s North Slope. Males have much larger ranges than females. On the Alaska Peninsula, seasonal ranges average over 100 square miles.

Resource extraction has many negative effects on brown bears, but among the most common and severe impacts documented in the literature are those from road construction. A 2014 study of brown bears in Alberta found that:

One of the principal factors that have reduced grizzly bear populations has been the creation of human access into grizzly bear habitat by roads built for resource extraction. … Roads have also affected movements and distribution of bears, changes in behavior relative to roads, and changes in body condition and survival rates relative to roads, and have caused fragmentation of populations.¹⁷⁹

The study notes that “the [scientific] literature contains numerous publications looking at the negative consequences of roads for grizzly bear populations.” Roads increase the likelihood of legal hunting which can increase mortality pressures on the population. Roads may increase risks from illegal hunting or poaching. And roads increase bear-human interactions and associated defense of life or property (DLP) killings. This is always problematic as humans increase their activities in bear habitat. DLPs are particularly hard to control.

The EIS should assess the:

• Density of bears within 20-30+ miles of the mine site and associated road corridors (including the Ambler Road);
• Home range sizes of bears in the affected area;
• Daily and seasonal movements within the affected area;
• Risks of increased brown bear mortality within the affected area (including any nearby federal conservation units) as a result of road construction.

In addition to the direct impacts of the road corridor, the EIS must consider the potential impacts to caribou, salmon, and other prey species, and how such losses would in turn affect brown bears.

XI. Air Quality and Emissions

The short-term and long-term air emissions from the proposed project may result in direct, indirect, and cumulative impacts on the environment and human health. The EIS must take a hard look at the direct, indirect, and cumulative impacts associated with air quality from project emissions. The EIS must:

• Identify the physical, climatological, meteorological, and visibility characteristics of the project area, which are important to understanding air pollution and transport. Include the representative climate data in the vicinity of the project, including mixing height information, a discussion on whether the data is representative enough to characterize movement of the air mass in the area of interest, and a discussion of variables that affect air pollution and the fate and transport of pollutants, including air dispersion patterns, complex terrain interactions, extreme temperature affects, seasonal variations, and presence of other atmospheric phenomena;
• Discuss surrounding topography, pollutant transport and dispersion, and potential secondary formation of air pollutants;
• Provide existing baseline air quality data, including on a map the locations and terrain elevation of all past and present air quality and meteorological data collections stations, methods and frequency of monitoring, criteria air pollutants (e.g. SO2, NO2, CO, O3, PM10, PM2.5. and Pb), measured maximum, minimum, and average concentrations, data quality assurance, and quality control;
• Describe the natural resources, ecosystems and human communities that may be adversely affected by any additional air emissions, including critical habitat areas or sensitive areas, wildlife refuges or sanctuaries, sensitive wetlands and waterbodies, threatened and/or endangered species or species of special concern, water resources, or archaeological or cultural resources;
• Discuss project area air quality designations (i.e., attainment, non-attainment or unclassified), if any and the need to conduct conformity analysis;
• Discuss and provide a map showing the project definition of ambient air;
• Summarize and discuss the representativeness of the measured air quality data used for background levels;
• Develop an air emissions inventory to provide a comprehensive accounting of the sources and the total quantities of air pollutant emissions from all aspects of the proposed project and alternatives. Emission sources considered should include support activities, such as site preparation, project construction and start-up, as well as operations, maintenance, reclamation and closure activities. An emissions inventory should cover all potential pollutant releases and cover a specific geographic area for a certain timeframe. Include scaled schematics and process flow diagrams that identify product flow and emission-generating activities and points. Fugitive emission points, emission leaks, and ancillary activities that have the potential to generate air emissions should also be included;
• Provide emission inventories of all project combustion and non-combustion, mobile and stationary sources. This would include sources of emissions during the construction and operation phases, and the total quantity of air pollutants emitted (e.g., diesel engines, turbines, mobile sources, aircraft, and fugitive road dust);
• Identify any nearby sensitive receptors and vulnerable populations. Consider various pathways of exposure, such as direct contact, inhalation of particles or gaseous pollutants, and potential impacts to receptors as a result of pathway exposure;
• Identify and discuss applicable air quality laws, regulations, standards, and guidance. Verify the data meets the National Ambient Air Quality Standards and/or State standards, increments, and thresholds. Provide date(s) for any monitoring data that indicates an air quality violation. Identify and discuss required air quality permits;
• Include a plot plan/facility layout showing the ambient air boundary, location of all emission sources, buildings, structures, north arrow, and scale;
• Provide tables summarizing the data and model results, and graphics/isopleths to display the locations of predicted concentration. Include both a project-only analysis and a cumulative analysis;
• Identify the type of modeling used to predict changes in ambient air quality associated with the proposed action and alternatives;
• Provide and discuss the calculation methodologies and assumptions of all emission rates, both short-term (g/sec, lbs/hour, lbs/day) and long-term (tons/yr). This would include operating hours, fuels, heat input, etc.;
• Provide stack parameters for point sources (height, temperature, exit velocity and diameter), and dimensions for area and volume sources;
• Conduct and provide a Good Engineering Practice stack height analysis (i.e., Building Profile Input Program for PRIME);
• Discuss and provide a map showing the project modeling domain. This would include ambient air boundary, near field, far field, sensitive receptor locations, map scale, and north arrow;
• Identify the representative meteorological data that will be used with the EPA guideline or nonguideline model(s) to predict project concentration impacts during construction, startup/shutdown, and operation phases;
• Identify the EPA guideline or non-guideline that will be used to predict project compliance with air standards, increments, and de minimis levels. In addition, identify any options selected that are not regulatory defaults. (Note: If a non-guideline model is proposed to predict concentrations in complex terrain, inform the EPA as soon as possible. This approach will require a Section 3.2.2.e demonstration pursuant to Appendix W in 40 C.F.R. Part 51);
• Address secondary formation of O3 (ozone) and PM2.5 (fine particulates) through emissions of precursors (i.e., sulfates, nitrates and VOCs) in evaluating compliance with air quality standards;
• Include a list of project specific Hazardous Air Pollutants (HAPS) emitted, estimated quantity, and the mobile (e.g., trucks, vehicles, heavy equipment, airplanes) and stationary (e.g., mine processing facility, power generator) sources;
• Compare the emissions to the National Emissions Standards for Hazardous Air Pollutants (HAPs). Discuss whether the standards are achieved or explain why the standards have been exceeded;
• Identify and discuss the effectiveness of mitigation measures and control technologies that would be implemented to minimize the emission of HAPs.
• For any pollutants not considered in the analysis there should be a discussion regarding their omission, and an explanation why omitted pollutants are not expected to contribute to reasonable significant impacts;
• In the emissions inventory, include estimates of PM2.5 and PM10 (particulate matter) emissions from project sources during construction, operation, and reclamation/closure, such as the mine site, gravel roads and pads, gravel source sites, etc.;
• Evaluate the magnitude and significance of fugitive dust emissions (e.g., ore processing operations, gravel roads and pads, construction activates, support facilities, etc.) and impacts on human health and sensitive populations (e.g., children and elderly);
• Assess vehicle emissions.

XII. Geophysical Impacts

The Corps needs to fully assess the potential impacts to permafrost, as well as the mitigation measures necessary to prevent permafrost degradation from the project. Surface vegetation insulates permafrost, and disturbance of this vegetation by laying gravel can speed permafrost melt and result in subsidence. Geophysical changes associated with the construction of roads, camps, staging areas, laydown yards, waste-rock facilities, and other mine components will extend far beyond gravel footprints. Long-term impacts resulting from fugitive dust from the mine may contribute to an increased rate of permafrost degradation. The decrease in albedo may cause higher temperatures and increase thaw rates near mine infrastructure, roads, and camps. This problem would be further exacerbated by climate change. The Corps should closely examine not only existing permafrost conditions and how to mitigate against degradation of those conditions, but should also take into consideration the potential impacts of climate change and any additional measures that are necessary to account for rapidly changing conditions in the region.

Dust-related issues and contaminants associated with dust palliatives are a serious concern that the Corps needs to fully analyze in the EIS. Dust palliatives can contain dangerous contaminants that have the potential to pollute surface and groundwater resources. Dust fallout can extend hundreds, or even thousands of feet from the source, affecting vegetation throughout the area. Without information on the measures Ambler Metals will adopt to control dust, the Corps will be unable to determine the extent of adverse effects to permafrost, water, fish, and wildlife resources in the region, as well as the need for and effectiveness of potential mitigation measures. The Corps should not allow Ambler Metals to rely on a future promise to identify these measures; such measures need to be part of its application and fully analyzed as part of the EIS.

The Corps must also evaluate the potential for sediment contribution and particulate matter pollution from trucks using the Ambler road to carry materials to and from the mine, as well as any necessary mitigation measures to prevent contamination and other issues from those and other vehicles using the road. In particular, the Corps should evaluate a full range of potential impacts from ore trucks and should examine the potential for fallout in light of a range of potential mitigation measures.

XIII. Climate Change

NEPA requires agencies to assess the climate effects of direct greenhouse gas emissions from a project, such as emissions from construction activities, the indirect environmental impacts, such as degraded air quality, and the long-term cumulative impacts caused by the project’s development and continued activity. The Corps must analyze and quantify the direct, indirect, and cumulative impacts of emissions produced from mine operations, including operation of power generators, as well as all other greenhouse gas sources, including vehicle, airplane, helicopter, and vessel emissions.

The affected environment sets the “baseline” for the impacts analysis and comparison of alternatives. Excluding climate change effects from the environmental baseline ignores the reality that the impacts of proposed actions must be evaluated based on the already deteriorating, climate-impacted state of the resources, ecosystems, human communities, and structures that will be affected. This EIS must include comprehensive baseline data to characterize the existing environment, including seasonal and climatic changes over multiple years. Effects from climate change are already occurring and are expected to increase, resulting in shrinking or altered water resources, increased precipitation, extreme flooding and other weather events, invasion of more combustible non-native plant species, soil erosion, changes in season length, loss of wildlife habitat, and changes to migratory and other biological patterns.

The Corps also needs to fully quantify the contribution of the mine and mining activities to climate change. Mine operations increase the loss of permafrost and rate of permafrost melting via greenhouse gas emissions and permafrost disturbance, similar to that described for gravel roads above. The risk of melting permafrost leads to a higher potential for mine instability and tailings dam failures. The impacts of stormwater releases, spills, and tailings failures are further increased due to increased frequency and rate of large storm events due to climate change. Designing such facilities for a 24-hour/100-year storm event is no longer sufficient.

Many resources which the Corps must consider in its analysis are already vulnerable to the effects of climate change and project infrastructure will exacerbate these problems. Climate change impacts are and will continue to be part of the new normal, and the Corps’ analysis for this project must account for this reality.

The EIS should assess potential climate change effects associated with the project including:

• Greenhouse gas emissions associated with the project;
• Changes in the carbon cycle due to manipulation of natural carbon sinks and sources;
• Effects of climate change on the project (i.e., water management, road maintenance, revegetation, reclamation, and water treatment in perpetuity);
• Feasibility and effectiveness of any proposed adaptive management measures in response to meteorological/weather changes;
• Climate-change-induced effects on precipitation, snow pack, stream flows, and culvert sizing and effects on the project;
• Climate-change-induced changes to the hydrologic regime;
• Climate-driven wildlife and habitat changes, and changes in biomes.

The EIS must also analyze the cumulative impacts of the project, along with other reasonably foreseeable development in the region.

XIV. Subsistence Impacts

Many of the communities near the proposed mine rely heavily on wild fish, animal, and plant consumption to meet their nutrition requirements. Many communities do not have grocery stores, and those that do face costs two to three times higher than residents in urban Alaskan communities do. Given the high cost of food in these remote communities and the already significant concerns about food scarcity, any impact to subsistence resources would have a disproportionate impact on the quality of life in affected rural communities, including Ambler, Shugnak, and Kobuk. The EIS must acknowledge and thoroughly analyze the ways that the Arctic mine could reduce the availability of subsistence resources and restrict subsistence access in the area surrounding it and the areas surrounding any roads leading to and from the mine.

The proposed mine may impact subsistence by impacting user access across the road and potential avoidance of traditional subsistence use areas. Noise, traffic, and infrastructure associated with the project could affect the availability of key resources such as caribou, waterfowl, and furbearers including wolf and wolverine. Spills to water resources or that reach water resources, such as fish-bearing streams, could spread and thus have a wider potential impact area, such as an entire watershed. Subsistence harvesters often avoid areas of development due to concerns about contamination and because of residents’ discomfort about hunting near human or industrial activity. In addition, increased access provided by the mine and its associated transportation corridors (including the Ambler road), could increase competition from sport hunters (both authorized and via trespass). As a result, impacts to subsistence will extend far beyond the immediate footprint of the mine, causing the loss of subsistence use areas across a broad area.

Subsistence hunting and harvesting activities are central to the cultural identity and social cohesion of the communities in the region. The Corps needs to do a full study in each of the impacted communities to fully assess the subsistence, socioeconomic, cultural, and other impacts to the region.

XV. Public Health

There are a number of issues related to public health that the Corps should consider in the EIS. Impacts to public health could result through changes in diet and nutrition, exposures to contaminants from construction and mining, safety, acculturative stress, and economic impacts. The Corps must closely analyze the impacts from mining and any mining activities on air quality in the local communities. Moreover, public health in much of Alaska is already under stress from climate change, with anticipated health implications such as a greater rate of chronic and infectious diseases; damaged water and sanitation infrastructure; an increase in anxiety and depression; and increasingly dangerous hunting and harvesting conditions limiting subsistence activity.¹⁸⁰ The Corps should consider the health impacts of this project in the context of the changing climate.

Importantly, there is naturally occurring asbestos in the bedrock along portions of the proposed route and near the Ambler Mining District.¹⁸¹ This means there is tremendous potential for adverse health impacts to anyone involved in construction, traveling along the proposed access road, or in nearby communities.

The Corps should require that a full Health Impact Assessment (HIA) be completed for this project. HIAs provide a systematic analysis of the potential positive or negative effects of a project on the health of a population and the distribution of those effects within the population. HIAs also identify appropriate actions to manage or mitigate negative effects.

The HIA should give special attention to vulnerable populations, such as elderly, young children, and pregnant women, who all may be more susceptible to exposure. The HIA should include:

• A complete screening analysis to determine which aspects of human health (including, but not limited to, public, environmental, social, mental, and cultural health, etc.) could be impacted;
• Consider historical impacts to health and overall cultural well-being;
• Identify potential contaminants that may persist and bioaccumulate in the environment and up the food chain (e.g., consumption of berries, fish, game, drinking water, etc.);
• Identify pollutants of concern and their sources that represent health risks to local and regional communities;
• Identify pollutants of concern exposures, pathways, and susceptibilities;
• Identify pathways to exposure related to environmental impacts and subsistence resources;
• Include a profile of existing health conditions of the region;
• Identify strategies to mitigate and manage identified adverse health impacts—local communities and tribal governments should be involved in developing health strategies and mitigation measures;
• Evaluate potential health impacts of individuals and communities in the region;
• Evaluate the risks to local communities and vulnerable individuals from moving majority white male workers into rural, predominately Indigenous areas;
• Include the HIA as an appendix to the EIS.

XVI. Invasive Species

The EIS should take a hard look at the direct, indirect and cumulative impacts associated with the introduction of invasive, non-native species. Construction activities which disturb the ground may potentially expose areas and facilitate propagation of non-native invasive species. Climate change resulting in warmer temperatures may encourage invasive species growth, which may not normally occur at this climate zone. Invasive plant species can have numerous harmful impacts on native ecosystems, and increase wildfire risk. An invasive species management plan should be developed and incorporated into the EIS. The EIS should assess the effectiveness of Ambler Metals’ invasive species management plan. That plan should include:

• An invasive non-indigenous plant study (pre- and post- project construction);
• Mitigation and control measures to minimize the establishment of noxious invasive plant species;
• A monitoring plan during and after project construction to ensure that nonnative invasive species are not establishing in the area; and
• Utilization of native plants and grasses for restoration and reclamation of disturbed areas after project construction and during mine closure activities.

XVII. Environmental Justice

The EIS should analyze the impacts to the primarily Alaska Native, rural communities near the proposed mine. Factors such as the arrival of outsiders and the strain that puts on small communities with limited resources, the proven dangers of moving majority white male workers into rural Indigenous communities, social impacts, employment opportunities and changes, and other development pressures must be studied in the EIS.

Disruption of subsistence activities may affect social and kinship ties, many of which are based on the harvesting, distribution, and consumption of subsistence resources. The Corps must also analyze adverse effects to cultural systems beyond those related directly to subsistence. This project and the related Ambler road have a long history in the region, and these affected communities have had to engage in many meetings and review a variety of documents during different permitting processes. In addition, the mine has the potential to increase social and political tensions between different population sectors and community institutions that either support or oppose aspects of development. The Corps should consider the stress the permitting process will have on local communities.

XVIII. Federal Conflicts of Interest

This permitting process presents a significant conflict of interest for the Corps, as the federal government recently invested $35.6 million taxpayer dollars in Trilogy Metals, one of the co-owners of Amber Metals, in exchange for a 10% ownership stake in the company. As a result of this transaction, the government has a vested interest in the same project it is currently evaluating. The EIS should fully acknowledge this virtually unprecedented arrangement, and the Corps needs to take precautions to ensure that its review of this project is not biased by the government’s proprietary interest in the project. More broadly, the Corps should consider the ethical and legal ramifications of evaluating this project in light of the government’s substantial investment. The investment effectively places a thumb on the scales, subtly (or not so subtly) signaling support for the project before the environmental review has even begun. This raises substantial concern that the ongoing permitting process will be a fait accompli, and may not be conducted consistent with the public interest. The Corps should also evaluate whether this project is truly in the national interest, as the profits from mining will largely flow to foreign-owned mining conglomerates and the products from the mine will be exported to foreign markets, including China.¹⁸² At the very least, the government’s substantial investment in the project raises serious doubts as to whether the Corps can fulfill its Congressionally mandated duty to evaluate this project in a neutral and objective manner.