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Notice of Intent To Prepare an Environmental Impact Statement for the Proposed Caldwell Canyon Mine and Reclamation Plan, Caribou County, Idaho

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Bureau of Land Management, Interior.


Notice of intent.


In compliance with the National Environmental Policy Act of 1969, as amended (NEPA), and the Federal Land Policy and Management Act of 1976, as amended, the Bureau of Land Management (BLM) Pocatello Field Office, Pocatello, Idaho, intends to prepare an Environmental Impact Statement (EIS) to analyze the potential impacts of approving the proposed Caldwell Canyon mine and reclamation plan (MRP). The EIS will also consider Start Printed Page 14743the effects of lease modifications that are part of the proposed project. This notice announces the beginning of the scoping process to solicit public comments and identify issues to be addressed in the EIS.


This notice initiates the public scoping process for the EIS. Comments on issues may be submitted in writing until April 21, 2017. The date(s) and location(s) of any scoping meetings will be announced at least 15 days in advance through local media, newspapers, and the BLM Web site at:​2eoKYV8. In order to be addressed in the Draft EIS, all comments must be received prior to the close of the 30-day scoping period or 15 days after the last public meeting, whichever is later. We will provide additional opportunities for public participation upon publication of the Draft EIS.


You may submit comments related to the Caldwell Canyon Mine Project by any of the following methods:

Documents pertinent to this proposal may be examined at the Pocatello Field Office.

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David Alderman, BLM Pocatello Field Office, telephone (208) 478-6369; address 4350 Cliffs Drive, Pocatello, Idaho 83204; Information is also available at the BLM's Web site at​2eoKYV8. Persons who use a telecommunications device for the deaf (TDD) may call the Federal Relay Service (FRS) at 1-800-877-8339 to contact the above individual during normal business hours. The FRS is available 24 hours a day, 7 days a week, to leave a message or question with the above individual. You will receive a reply during normal business hours.

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P4 Production, LLC (P4), a subsidiary of Monsanto Company, has developed and submitted a mine and reclamation plan (MRP) for the Caldwell Canyon Phosphate Mine. The proposed mine is located along Schmid Ridge, approximately 13 air miles northeast of Soda Springs, Idaho. The BLM will serve as the lead agency for conducting the necessary environmental analysis. The Idaho Department of Environmental Quality, Idaho Department of Lands, and the U.S. Army Corps of Engineers will be cooperating agencies. Although a small amount of U.S. Forest Service (USFS) surface land is within the proposed project area, the USFS will not participate as a cooperating agency. The affected USFS lands are located on BLM-administered phosphate leases owned by Agrium, Inc. (Agrium) and managed as part of the Dry Valley Mine. Dry Valley Mine has been mined and fully reclaimed per the existing MRP for that project.

The proposed action includes a haul road across the reclaimed surface of the Dry Valley Mine and the partial filling in of the open Panel D pit with waste rock from Caldwell Canyon. A modification of the Dry Valley MRP to allow construction of the haul road and backfilling of the Dry Valley D Pit is necessary and will be evaluated as part of this EIS. No USFS special use permits or other decisions are needed to permit the project. The USFS will be routinely apprised regarding the progress of the environmental analysis and will be consulted regarding project aspects affecting USFS lands.

Operations at Caldwell Canyon would consist of open pit mining on the Federal Phosphate Leases IDI-02, IDI-014080, and IDI-13738. The mine would also include State of Idaho Mineral Lease E07959. P4 is requesting modifications to phosphate lease boundaries for each of these leases. All of the proposed lease modifications contain part of the proposed mine pit and are necessary to maximize ore recovery. Issuing these lease modifications is a discretionary decision that will be analyzed in the EIS. New mining operations at the Caldwell Canyon Mine would occur on Federal phosphate leases and public lands administered by the BLM, on National Forest System lands administered by the USFS, on a State of Idaho phosphate lease and state lands administered by Idaho Department of Lands (IDL), and on private lands. The public lands lie in the BLM Pocatello Field Office. The leases grant exclusive rights to the leaseholder to mine and otherwise dispose of the phosphate resource at the sites. Through development of this EIS, the BLM will analyze environmental impacts of the proposed mining and reclamation operations and reasonable alternatives to the proposed action. Appropriate mitigation measures will also be formulated by the BLM in conjunction with the proponent.

Agency Decisions

The BLM Idaho State Director, or delegated official, will make a decision regarding approval of the MRP and appropriate mitigation measures, the proposed Federal phosphate lease modifications and other appropriate land use authorizations for activities that take place off leased lands. Decisions will be based on BLM's authority, the EIS analysis, and any recommendations the cooperating agencies may have related to their jurisdiction, expertise, or permitting actions.

The proposed action has been reviewed for consistency with the 2012 Pocatello Field Office Resource Management Plan and, at this time, the project is generally consistent with the management direction in the Resource Management Plan. It is unlikely that any amendments to the Resource Management Plan will be needed.

The IDL will make an independent decision on approving a mine plan for state lease EO7959. IDL is a cooperating agency for the EIS and will consider the BLM's EIS in its decision making.

The Army Corps of Engineers may also make decisions related to permits under Section 404 of the Clean Water Act.


The MRP for Caldwell Canyon includes development of two open mine pits: North Pit and South Pit. Mining operations would be conducted over an estimated 40-year period using a pit panel mining method. Mining would be initiated in the mid-point of the South Pit and proceed southward. Approximately six million tons of initial overburden materials would be hauled to the inactive Dry Valley Mine Panel D and placed as backfill. All other overburden generated from each new panel would be used to backfill a previously mined panel. Once mining reaches the south end of the South Pit, mining would resume at the mid-point of the South Pit and proceed northward in the same fashion.

Ore would be transported via a two mile-long haul road linking the mine pit areas to an ore stockpile located off-lease at the East Caldwell Area. The haul road is mostly on lease or on private land but a small section is off lease on BLM land and will require a right of way. The ore stockpile would be located adjacent to an ore loadout facility, which would be used to load ore into a train for rail transport by existing rail line to P4's processing plant at Soda Springs. The proposed stockpile and ore loadout site was previously used by Agrium during active mining operations at the Dry Valley Mine. Selected materials generated from development of the initial pit panel would be used for the construction of haul roads. Once P4 has hauled the initial overburden to the Dry Valley Pit Start Printed Page 14744(estimated to occur during the third year of production at Caldwell Canyon), overburden generated from each subsequent pit panel would be used to backfill pit panels in sequence in the South and North pits of the Caldwell Canyon Mine.

Hauling overburden from the Caldwell Canyon South Pit to the open pit at Dry Valley Mine would require construction of an additional two-mile long haul road from the ore stockpile area to the Dry Valley Pit (Panel D Pit) across reclaimed areas of the Dry Valley Mine. Construction, operation, maintenance, grading, and reclamation of this haul road would be the responsibility of P4 and are addressed in the MRP for Caldwell Canyon. Agrium, as the Dry Valley mine owner, is ultimately responsible for the final reclamation at Dry Valley. Agrium would place the final cover/growth media on the partially backfilled Panel D pit and haul road and revegetate the reclaimed surface.

Mining below the water table would occur at the south and north ends of the Caldwell Canyon South Pit; mining in these areas is expected to occur during years 6-8 and 14-16 of production, respectively. In these locations, P4 would install ground water interception wells to draw down the water table to an elevation below the planned pit bottom. This would reduce the amount of ground water flowing into the pit. The water would be stored in water management ponds until water quality meets infiltration criteria at which point it would be infiltrated into the ground water. The sequestered water would not be allowed to leave the mine site other than by infiltration or evaporation. With the exception of one culverted haul road crossing, P4's MRP proposes to avoid Caldwell Creek, which is a small non-connected/non-fish bearing stream that runs between the north and south pits.

All overburden and waste material would be backfilled into mine pit panels and reclaimed using an earthen cap to reduce infiltration of precipitation, groundwater and surface water, and to support establishment of vegetation to meet post-closure land use goals. The proposed cap is a capillary break design consisting of 1.5 feet of topsoil and 2.5 feet of alluvium and colluvium over two feet of cherty material taken from overburden at the site.

Mining operations at Caldwell Canyon would disturb approximately 1,530 acres. Some mine facilities (ore stockpile, tipple, water management infrastructure, offices, shop and storage facilities) would be located in the East Caldwell Area in Dry Valley. Additional facilities located at the Caldwell Canyon mine site include service and haul roads, water pipelines, water management ponds, sediment control ponds, infiltration galleries, growth media stockpiles, and other facilities.

P4 and Agrium would obtain governmental agency approvals necessary to allow placement of overburden into the Dry Valley Pit in accordance with a proposed Dry Valley Mine Plan Modification. The mine plan modification would be analyzed as part of this EIS.

Alternatives and Schedule

The EIS will analyze the Proposed Action (approving the MRP and lease modifications) and the No Action Alternative. Other mining alternatives may be considered that could resolve important issues or provide mitigation of potential impacts.

The tentative EIS project schedule is as follows:

  • Begin public scoping period and meetings: Early 2017.
  • Estimated date for draft EIS and associated comment period: Fall 2017.
  • Final EIS publication: Spring 2018.
  • Record of Decision: Spring 2018.


The purpose of the public scoping process is to identify relevant issues that will influence the scope of the environmental analysis, including alternatives, and guide the process for developing the EIS. The BLM has identified some preliminary issues associated with the Caldwell Canyon Mine Project:

  • Potential impacts to groundwater and surface water quantity and quality;
  • Impacts to vegetation including rare species and species important to Native Americans;
  • Impacts to soil and mineral resources;
  • Impacts to air quality from vehicle emissions and fugitive dust;
  • Potential reductions of wildlife and their habitats, including the Greater Sage-Grouse;
  • Potential reductions in livestock grazing;
  • Impacts to wetlands and riparian habitat;
  • Impacts to recreation including hunting and camping;
  • Socio-economic effects such as increased employment and the continued operation of an elemental phosphorous plant and support businesses;
  • Impacts to Native American rights, treaties, and land uses;
  • Impacts to visual resources from the development of the mine; and
  • Impacts to resources from the cumulative effects of the multiple mines in southeast Idaho.

The BLM will continue to refine these issues during the scoping process.

The BLM will use and coordinate the NEPA scoping process to help fulfill the public involvement requirements under the National Historic Preservation Act (54 U.S.C. 306108) as provided in 36 CFR 800.2(d)(3). The information about historic and cultural resources within the area potentially affected by the proposed action will assist the BLM in identifying and evaluating impacts to such resources.

The BLM will consult with Indian tribes on a government-to-government basis in accordance with Executive Order 13175 and other policies. Tribal concerns, including impacts on Indian trust assets and treaty rights and potential impacts to cultural resources, will be given due consideration.

Federal, State, and local agencies, along with Tribes and other stakeholders that may be interested in or affected by the proposed Caldwell Canyon Mine are invited to participate in the scoping process. Agencies with regulatory authority or special expertise, if eligible, may request or be requested by the BLM to participate in the development of the environmental analysis as a cooperating agency.

Before including your address, phone number, email address, or other personal identifying information in your comment, you should be aware that your entire comment—including your personal identifying information—may be made publicly available at any time. While you can ask us in your comment to withhold your personal identifying information from public review, we cannot guarantee that we will be able to do so.

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Authority: 40 CFR 1501.7.

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Mary D'Aversa,

District Manager, BLM Idaho Falls District.

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[FR Doc. 2017-05679 Filed 3-21-17; 8:45 am]