Comment letter on USACE on Kensington Mine POA-1990-00592-M9

December 9, 2020

Mr. Randy Vigil, Project Manager
U.S. Army Corps of Engineers
Alaska District – Juneau Field Office
P.O. Box 22270
Juneau, AK 99802-2270
Submitted electronically to: [email protected]


Subject: POA-1990-00592-M9, Public Notice of Application for Permit – Coeur Alaska, Inc. Kensington Mine Plan of Operations Amendment 1 (POA 1)

Dear Mr. Vigil:

The Resource Development Council for Alaska, Inc. (RDC) is writing to comment on Coeur Alaska, Inc.’s (Coeur) permit application your office is processing for a Department of the Army permit. Coeur’s permit application describes the additional discharge fill material into waters of the U.S. for a life of mine extension for the Kensington Mine. The U.S. Forest Service (USFS) is conducting a Supplemental Environmental Impact Statement (SEIS) for the Kensington Mine Plan of Operations Amendment 1 (POA 1) to which the U.S. Army Corps of Engineers is participating in the development of the SEIS as a cooperating agency. 

RDC is a statewide trade association comprised of individuals and companies from Alaska’s fishing, forestry, mining, oil and gas, and tourism industries. RDC’s membership includes Alaska Native corporations, local communities, organized labor, and industry support firms. RDC’s purpose is to encourage a strong, diversified private sector in Alaska and expand the state’s economic base through the responsible development of our natural resources.

Our comments pertain to the U.S. Army Corps of Engineers (USACE) permit process in the areas of a commenter’s expertise, the National Environmental Policy Act (NEPA; 33 CFR 325 Appendix B), the U.S. Army Corps of Engineers permit processing procedures and your decision-making criteria stemming from the public interest review (33 CFR 320.4(a)) and the Environmental Protection Agency’s Section 404(b)(1) Guidelines (40 CFR 230).

Permit Processing Procedures

Consideration of Comments

RDC respectfully requests USACE take into account RDC’s long history of experience in matters contained in this letter in accordance to 33 CFR 320.4(a)(3). RDC’s expertise is based upon our membership’s experience in business, engineering, mining, construction, environmental services, and Federal regulatory laws and policy.

Deference to State Dam Safety Programs

The proposed POA 1 Stage 4 Dam raise at the Tailings Treatment Facility (TTF) is classified as a Hazard Class II dam under the Alaska Department of Natural Resources (DNR) Dam Safety Program’s hazard potential classification system. The Stage 4 Dam design complies with, and exceeds, the state dam safety criteria by using the more stringent criteria required for Hazard Class I dams. Per USACE’s regulations (33 CFR 320.4(k)) which state that non-Federal applicants may be required to demonstrate that impoundment structures “comply with established state dam safety criteria…” we believe the Stage 4 Dam will therefore also comply with USACE permit review regulations and an independent review by USACE will not be necessary.  

National Environmental Policy Act

Advance to Final SEIS and Record of Decision (ROD)
USACE’s work supporting the USFS’s completion and publication of the FSEIS should be undertaken with urgency given the fact that the USFS has not found POA 1 to contain any significant impacts on the human environment. In following, the USACE’s Record of Decision should select the POA 1, the Proposed Action, without delay.

Limited NEPA Scope of Analysis
RDC supports USACE in limiting the scope of analysis for its NEPA evaluation to the specific activities requiring a DA permit per the criteria 33 CFR 325 Appendix B (7)(b). Specifically, USACE should focus its review on those impacts that may occur from the placement of fill material into waters of the U.S. (WOTUS) This is appropriate as the regulated activity does not comprise “merely a link” in a corridor type project, there are not aspects of the upland facility in the immediate vicinity of the regulated activity which affect the location and configuration of fill placement, and a small percentage of the overall activity is within USACE jurisdiction (27.2 acres of fill in WOTUS relative to a total disturbance footprint of approximately 150 acres). Finally, the extent of cumulative federal control and responsibility over the project (approximately 66% on USFS lands), does not warrant expansion of the USACE’s scope of analysis to encompass non-regulated activities. Overall, USACE should refrain from ‘federalizing’ the project and expanding its NEPA scope of analysis outside of the activities subject to its authority.

USFS DSEIS Chapter 2.5 Alternatives Considered by Eliminated from Detailed Study
We believe the analysis conducted by the USFS and the Cooperative Agencies on this set of alternatives is reasonable, represents a logical thought process and reaches justifiable conclusions. We are particularity supportive of the USFS and Cooperating Agencies eliminating the No TTF Lake at Closure ( and the Mill Processing Rate Partially Based on Volume of Tailings Backfilled the Prior Month ( Alternative.  

TTF with Reduced Water Closure Alternative

The TTF Closure with Reduced Water Alternative does not include POA 1’s fish habitat improvements and would greatly reduce the amount of aquatic habitat after closure. Following mine closure, the resulting waterbody would be small, shallow, and is unlikely to function as a healthy lake (DSEIS pg. 3-65). It would not provide Dolly Varden spawning habitat. The existing graphitic phyllite (GP), which can lead to acid drainage, near the dam may not be sufficiently contained and additional GP may be exposed to obtain additional growth media at the nearby borrow site. During closure and reclamation there are also major concerns regarding the ability to safely operate heavy machinery on deposited tailings. Due to the lack of environmental benefits, risks surrounding managing a current source of GP as well as a new source of GP, and for safety reasons, this alternative should not be selected.

Johnson Creek Waste Rock Storage (WRS) Alternative

The Johnson Creek WRS is the only proposed WRS option that would not expand on an existing WRS, but instead would be a new stand-alone WRS located almost entirely on National Forest Service land, requiring construction of an additional access road. Use of this proposed WRS site would present new and serious safety concerns related to increased traffic and haul distance required to access the site. The fact that the access road and a portion of the Johnson Creek WRS would be located within an active avalanche area raises additional safety concerns and may result in restricted access to the WRS during the winter and spring.


Public Interest Review

The DSEIS documents potential impacts to wetlands and other waters of the U.S. that could result from POA 1 (Section 3.4). Most impacts would be to low or moderate functioning wetlands (pg. 3-37). Furthermore, as described in Coeur’s Department of the Army permit application, POA 1 would require long term placement of fill in just 27.2 acres of WOTUS and 26.4 acres of upland habitat would be converted to WOTUS at the TTF at closure. Thus, the project overall will have just a 0.8-acre net decrease in WOTUS. Based on this data, we support a conclusion that POA 1 would not result in significant impacts to aquatic resources or aquatic resource functions within the affected watersheds. 

Water Quality 

For over ten years Coeur has shown that they can operate the Kensington Mine in an environmentally responsible way. Their current plan to use existing infrastructure to expand the current tailings treatment facility and waste rock storage sites and only adding one more waste rock site will have the least impact on the environment. With these features come numerous best practices to protect the environmental qualities of the area, not the least of which is water quality. Coeur has incorporated the highest level of technology in terms of advanced water treatment and waste management and will continue to protect water quality, in partnership with the USFS and the Alaska Department of Environmental Conservation.

Consideration of Property Ownership

Use of private land for private purposes can benefit both the private landowner and the public. Coeur’s application to USACE for a permit to construct, operate, and close POA 1 is an exemplary example of such a project. Issuance of this permit will allow for a reasonable balance of the rights afforded a private property owner to realize economic opportunities while the mineral production and environmental protections Coeur has incorporated into POA 1’s design features, that exceed the standards of environmental responsibility, fittingly considers the needs of the public. 

As for POA 1’s use of public lands, the same is true. Coeur’s proposal is consistent with Tongass National Forest’s 2016 Forest Plan (Plan) which has as a stated goal to support mineral development. Coeur’s design, construction, operation and monitoring the State 3 dam at the Tailings Treatment Facility meets the highest standards of the State of Alaska even though the State’s regulatory requirement of this type of structure was less than Coeur chose to implement. Coeur is maintaining their same approach with POA 1’s State 4 dam raise.  

For these reasons, we urge USACE to give heavy weight to the consideration of property ownership and find POA 1 to be not contrary to the public interest.

Section 404(b)(1) Guidelines

Coeur’s proposed POA 1 complies with the EPA’s 404(b)(1) Guidelines found in 40 CFR 230. As previously noted, POA 1 represents the least environmentally damaging practicable alternative when effects to aquatic resources during both operations and following reclamation are considered. POA 1 proposes long-term placement of fill in just 27.2 acres of Waters of the U.S. Again, at closure, 26.4 acres of upland habitat would be converted to WOTUS at the TTF. Thus, the project overall would have a 0.8-acre net decrease in WOTUS. The Final SEIS should provide similar analyses for other action alternatives to allow side-by-side comparison. 

POA 1 would also minimize impacts to fish and fish habitat. POA 1, as proposed, would also provide long-term, reliable mitigation (avoidance) of impacts to fish from the accidental release of acid rock drainage, a benefit over other alternatives evaluated. Finally, POA 1 includes fish habitat enhancements in Upper Slate Creek and South Creek and, at closure, would restore downstream fish passage into and through Lower Slate Lake to East Fork Slate Creek.

Economic Impacts of Kensington Mine

The Kensington Mine is the second largest employer and property taxpayer in Juneau, spending over $55 million in wages in 2019. The mine also paid $2.3 million in local sales and property taxes in 2019, while making community donations of over $143,000. It is clearly an economic engine for Southeast Alaska with a strong commitment to protect the environment. 


The Draft SEIS’s analysis of the Proposed Action clearly and reasonably demonstrates Coeur’s Life of Mine Extension will not have significant adverse effects on the human environment. The lack of significant adverse effects lends itself to USACE concluding POA 1 is not contrary to the public interest and also compliant with the Section 404(b)(1) guidelines. These conclusions are also support by Coeur’s successful and environmentally responsible operational history at the mine, Juneau and Southeast Alaska’s need to continue receiving the substantial positive economic impacts Coeur brings to the region, and the mitigation measures, those that will be on-going as well as the new fish habitat enhancements and long term inundation of graphitic phyllite at the TTF. For all these reasons, we urge the USACE to support the USFS with promptly finalizing the SEIS and issuing your ROD in favor of POA 1. 

Thank you for the opportunity to comment on this important project.