Compiled EOI and Appendices_09182026.docx

DEPARTMENT OF ENERGY Expression of Interest—DOE’s Office of Environmental Management (DOE-EM) Critical Minerals and Materials Inventory.

AGENCY: Office of Environmental Management, Department of Energy.

ACTION: Expression of Interest (EOI).

SUMMARY: The U.S. Department of Energy (DOE) Office of Environmental Management (EM) publishes the following questions regarding potential collaboration with interested parties for the reuse of its critical and rare earth minerals and materials. The goal is to ensure surplus critical minerals and materials within the DOE inventory are repurposed to bolster and diversify the U.S. supply chain. This will support domestic scientific, manufacturing, and energy needs.

A list of materials and minerals in DOE’s inventory is supplied as an attachment. Respondents should note that industry partners would be responsible for the subsequent extraction or reprocessing of the material.

THIS IS AN EXPRESSION OF INTEREST ONLY. THIS NOTICE DOES NOT CONSTITUTE A NOTICE OF FUNDING OPPORTUNITY (NOFO). A NOFO DOES NOT EXIST AT THIS TIME. DOE will not provide funding or compensation for any information submitted in response to this EOI. This EOI is not seeking or accepting applications, and a response to this EOI will not be viewed as a binding commitment to develop or pursue the ideas discussed. No material submitted for review will be returned.

DATES: Responses to the EOI must be received no later than November 2, 2026. A virtual Industry Day will be held on September 30, 2026. For questions and a link to attend, please email Rob Seifert, robert.seifert@em.doe.gov.

ADDRESSES: Interested parties are to submit comments electronically to robert.seifert@em.doe.gov with the subject line “EM Critical Minerals Inventory” no later than November 2, 2026. All responses must be submitted as a Microsoft Word document (.doc/.docx) of no more than five (5) pages in length, with black, Times New Roman, 12-point font, and 1-inch margins as an attachment to an email. The document cannot exceed 2MB in size. Only electronic responses to the above email address will be accepted. DOE will not consider responses submitted by any other means. Note: If clicking on the above link gives you an error message, you must CUT AND PASTE the URL into your browser to reach the web page.

FOR FURTHER INFORMATION CONTACT: Rob Seifert, (301)-250-5239, robert.seifert@em.doe.gov.

Questions seeking input on potential collaboration with DOE-EM on Critical Minerals and Materials Inventory Specific Questions:

Note: The terms recovery, reuse, repurposing, and reprocessing are viewed as interchangeable in this context but DOE will use the term reuse throughout for consistency.

1. What specific needs or demands does your organization have for rare earth metals, critical minerals, or materials that could be met by the DOE inventory?

2. Describe your organization's technical capabilities and experience in handling, processing, mining, or extracting rare earth metals, critical minerals, or materials.

3. Please detail your proposed plan's material requirements, specifying the minimum viable quantity, the optimal quantity for maximizing impact, and how the plan's scalability accommodates varying amounts from the available inventory.

4. What potential applications, domestic sectors, or market demand does your organization foresee for your proposed reuse?

5. Describe how your proposed reuse of inventory material(s) and any resulting products will primarily benefit U.S. domestic needs and contribute to the resilience of the U.S. energy and manufacturing supply chain.

6. How would your organization propose collaborating with DOE-EM to facilitate the reuse of the inventory materials?

7. Outline any significant technical, logistical or regulatory challenges anticipated in the reuse of material(s) from the DOE inventory and how these would be addressed or contingency plans.

8. What are your proposed plans for the management and disposal of any waste streams or byproducts generated from your processing or repurposing activities involving the inventory materials?

9. Would your organization be interested in exploring the possibility of leasing land or developing a facility on a site for material processing, repurposing, or related activities? If so, please provide details on your potential interest and any requirements or considerations for such an undertaking.

Proprietary Business Information: To the extent possible, DOE recommends that responders to this EOI do NOT provide confidential information. However, if this cannot be avoided, pursuant to 10 CFR 1004.11, any person submitting information that he or she believes to be proprietary business information and exempt by law from public disclosure should submit via email two well-marked copies: one copy of the document marked as Controlled Unclassified Information – Proprietary Business Information or “CUI//PROPIN” per 18 U.S.C. § 1905 with clear delineations therein as to which information is believed to be proprietary business information, and one copy of the document marked unclassified, uncontrolled information or “UUI” with the information believed to be CUI//PROPIN deleted. Submit these documents via email. Failure to comply with these marking requirements may result in the disclosure of the unmarked information under the Freedom of Information Act or otherwise. DOE will make its own determination about the confidential status of the information and treat it according to its determination. The federal government is not liable for the disclosure or use of unmarked information and may use or disclose such information for any purpose as authorized by law.

Signing Authority: This document of the Department of Energy was signed on XXXXX, by XXXXXX, Office of Environmental Management, pursuant to delegated authority from the Secretary of Energy. That document with the original signature and date is maintained by DOE. For administrative purposes only, and in compliance with requirements of the Office of the Federal Register, the undersigned DOE Federal Register Liaison Officer has been authorized to sign and submit the document in electronic format for publication, as an official document of the Department of Energy. This administrative process in no way alters the legal effect of this document upon publication in the Federal Register.

Critical Mineral Resource Potential at Paducah Site Bounding Analysis U.S. Department of Energy, Office of Environmental Management

Executive Summary Approximately 8,000 tons (56 million pounds) of aluminum and 2,000 tons (4 million pounds) of copper have been identified in legacy inventories at the U.S. Department of Energy (DOE) Paducah Gaseous Diffusion Plant site in Kentucky. These large inventories, along with 0.75 tons (1,500 pounds) of tungsten, two silver inventories (500 pounds of silver-tungsten alloy contacts and 0.3 pound of machine turnings), 76 pounds of platinum, and 1,000 pounds of selenium, represent a substantial domestic resource of critical materials derived from historical site operations. Comment by Akers, Holly: Let’s be consistent Based on initial characterization, the materials are present in consolidated forms, including solid process-gas equipment, electrical windings, breaker alloys and contacts, machine turnings, resistors, and clean platinum wire. Aluminum, and copper are primarily surficially contaminated with uranium. Aluminum and copper are rated “Feasible”; tungsten, selenium, and the 500-pound silver-tungsten inventory are rated “Good”; the 0.3 pound silver inventory is rated “Excellent”; and a process exists to extract the platinum.

These estimates are based on site inventory data and should be considered bounding figures. The materials are already mined, processed, and consolidated at a single, secure industrial site with direct access to major infrastructure. The Paducah portfolio remains a near-term opportunity to convert legacy material into a domestic resource, subject to characterization, decontamination, and project-specific economic evaluation.

1. The Material

1.1 What Is There

The critical mineral inventories at the Paducah site are byproducts of the site's long-standing historical mission as a uranium enrichment facility. The materials are not raw ores but processed metals, components, and alloys recovered from decommissioned infrastructure. They include aluminum process-gas equipment from compressor/cooler systems; copper from large electrical motors; tungsten and silver in high-voltage breaker components; additional silver machine turnings; platinum clean wire; and selenium-bearing resistors.

1.2 Location

All identified inventories are located within the controlled-access boundaries of the Paducah Gaseous Diffusion Plant site in Paducah, Kentucky. Specific locations referenced in the inventory data include compressor/cooler process-gas equipment, plant electrical switchyards, Power Operations (PG) buildings, and the C-720 building. This consolidation at a single industrial complex is a significant logistical advantage.

1.3 Material Distribution and Form

The materials exist in solid, recoverable forms that are conducive to industrial-scale handling and processing:

· Aluminum: Present as approximately 8,000 tons of solid process-gas equipment in PAD compressor/cooler systems.

· Copper: Exists as electrical windings from large motors in the Power Operations facilities.

· Tungsten and Silver: Co-located in silver-tungsten alloy high-voltage breaker contacts in the PAD switchyards.

· Silver: A separate 0.3 pound inventory of machine turnings is located at PAD C-720.

· Platinum: Present as 76 pounds of clean wire at PAD C-720.

· Selenium: Contained in resistors within electrical cabinets in the PAD PG buildings; the material is identified as RBA.

2. Bounding Inventory and Grade Data

2.1 Summary by Material Type

The data summarized here are derived from internal DOE inventory collection forms. The information highlights a portfolio of materials with high recovery potential.

Table 1. Bounding In-Place Inventory and Extractability Estimate for the Paducah Site

3. Key Considerations

3.1 Material Characteristics

· Contamination: The primary contaminant for the aluminum and copper inventories is surficial uranium. The selenium-bearing resistors are identified as RBA. The silver-tungsten alloy has no listed contaminants, the 0.3 pound silver inventory has no listed contaminant, and the platinum is described as clean wire. Comment by Akers, Holly: Spell out acronyms

· Extractability and Recovery: The recovery profile is positive but varies by stream. Aluminum and copper are rated “Feasible.” Tungsten, selenium, and the 500-pound silver-tungsten inventory are rated “Good.” The 0.3 pound silver inventory is rated “Excellent,” and a process exists to extract platinum.

3.2 Infrastructure and Access

· The Paducah site is a major, secure industrial complex with direct access to road, rail, and river transportation corridors.

· Decades of DOE operations have established robust infrastructure, including heavy utilities, support facilities, and a workforce skilled in handling industrial and radiological materials. This existing framework eliminates major capital hurdles for a potential recovery operation.

3.3 Economic Context

The economic case for the Paducah inventories is promising but should not be characterized as demonstrated by a Paducah third-party recovery agreement. The elimination of mining, crushing, and milling costs provides a potential advantage, but each stream remains subject to characterization, decontamination, processing, and project-specific economic assessment.

4. Historical Precedent: DOE Asset Management and Metals Recycling Programs

4.1 Background

The DOE and its predecessor agencies have a multi-decade history of managing, recycling, and recovering valuable materials from legacy infrastructure. These initiatives, particularly those under the Office of Environmental Management, provide a direct historical precedent for the recovery actions contemplated for the Paducah inventories. Past programs focused on reducing long-term liabilities and, where possible, returning assets to productive use.

4.2 Historical Precedent: Gaseous Diffusion Plant (GDP) Metals Decommissioning The most directly relevant historical precedent is the broader decommissioning program for the Paducah, Oak Ridge, and Portsmouth Gaseous Diffusion Plants. These massive efforts generated vast quantities of scrap metal, primarily steel, and copper.

· Grade Comparability and Process Applicability: The copper inventory at Paducah is the direct result of past operations. Historically, metals with manageable surficial contamination were often successfully decontaminated and free-released. The current Paducah inventories represent a continuation of this practice, now applied to materials whose value has increased dramatically. The processes for handling and decontaminating surficially contaminated scrap are well-established, forming a reasonable starting point for any recovery concept.

· Scale Advantage: The Paducah copper inventory is a large, consolidated resource. This scale is a substantial advantage, improving per-ton economics by distributing the fixed costs of mobilization, characterization, and processing across a multi-million-pound resource base.

· Commodity Price Context: An issued EOI for Paducah nickel is a direct indicator of current DOE interest in recovery concepts. It does not, by itself, establish commercial viability for the material offered in this EOI. Any recovery proposal remains subject to material characterization, decontamination performance, processing costs, and market conditions.

Critical Mineral Resource Potential at the Oak Ridge Reservation

U.S. Department of Energy, Office of Environmental Management

Executive Summary Approximately 10,000 pounds of lithium hydride, about 1.39 pounds of cesium-137 chloride, and approximately 1,000 grams of platinum have been identified in legacy inventories at the U.S. Department of Energy (DOE) Oak Ridge Reservation. These materials are the result of historical site operations at Oak Ridge National Laboratory (ORNL) and former gaseous diffusion plant facilities and represent a potential domestic source of critical materials.

Based on internal characterization data and historical reports, the materials exist in a variety of forms and conditions. Lithium hydride is contained within large shield assemblies, while cesium-137 chloride is present in sealed, highly radioactive sources. The ORNL platinum inventory consists of small bowls at Building 2026 and is rated “High” for extractability, although it is contaminated with cobalt, cesium, and strontium.

These estimates are based on a limited sample population relative to the total scale of the inventories and should be considered bounding figures only. The material is already consolidated at secure, highly developed DOE sites with direct access to critical infrastructure. While significant processing challenges related to contamination exist for some inventories, the potential to recover these materials aligns with national strategic goals for securing domestic supply chains for energy and technology manufacturing. Any party seeking to advance a recovery concept would be expected to conduct independent sampling, characterization, and metallurgical test work as a foundational step.

1. The Material

1.1 What Is There

The critical material inventories at Oak Ridge consist of processed materials and legacy assets remaining from historical missions in uranium enrichment, isotope production, and materials research. The lithium hydride, cesium-137 chloride, and platinum inventories are byproducts of research, development, and operational programs conducted at ORNL. These are not raw ores, but processed materials of varying form and purity.

1.2 Location

The inventories are located within the Oak Ridge Reservation in Tennessee:

· Oak Ridge National Laboratory (ORNL): ORNL houses the cesium-137 chloride sources, lithium hydride shields, and platinum inventory. Building 3517 contains hot cells and cesium sources, and the platinum inventory is located at Building 2026.

1.3 Material Distribution and Form

The materials exist in diverse physical forms and distributions across the sites:

· Lithium Hydride: Present as solid lithium hydride within large shield assemblies. One large shield is considered more readily recoverable because it can be disassembled; the remaining shields are sealed and more difficult to access.

· Cesium-137 Chloride: Stored as processed/purified cesium chloride (CsCl) in sealed sources within shielded casks and hot cells at ORNL Building 3517.

· Platinum: Approximately 1,000 grams are present as small bowls at ORNL Building 2026.

2. Bounding Inventory and Grade Data Table 1. Estimated Bounding Inventory of Other Oak Ridge Materials

Qualitative extractability categories: “Low” means that a recovery pathway has not been demonstrated for the inventory and substantial technology development, characterization, or decontamination is expected. “Medium” means that recovery appears technically plausible but would require significant disassembly, remote handling, shielding, hot-cell work, or other specialized processing. “High” means that the material is comparatively accessible and established handling or recovery steps are available, although radiological characterization, authorization, and applicable release requirements still apply. These ratings are relative screening categories for prioritization; they do not establish economic viability, regulatory readiness, or eligibility for unrestricted reuse or recycling.

3.1 Material Characteristics

· Contamination: Radiological contamination is the primary consideration for the largest inventories.. The cesium-137 chloride sources are highly radioactive and have cesium-137 and strontium-90 surface contamination. Lithium hydride is present in shield assemblies with reported activation products. In this context, “activation products” are radionuclides formed when shield materials are exposed to neutron flux. Available information identifies activation products in three shields and uranium in one shield, but it does not establish whether every shield was exposed to neutron flux or characterize every shield to the standard needed for a reuse or recycling release decision. The platinum is contaminated with cobalt, cesium, and strontium.

· Shield Characterization: Existing information is bounding. Radiological control (RadCon) smears from a limited number of shields characterize removable surface contamination at the sampled locations. MicroShield modeling was then used to develop a nuclide ratio for a disposal profile based on the available information and modeling assumptions. This approach supports bounding disposal planning, but it does not establish fixed or internal contamination, material composition, or release eligibility for each shield. Before recovery, shield-by-shield radiological and material characterization appropriate to the proposed handling, processing, reuse, or recycling pathway would be required.

· Extractability: The recovery potential varies by inventory. DOE has issued an expression of interest[footnoteRef:1] to develop decontamination and recovery technologies. Cesium-137 chloride and lithium hydride are rated “Medium” because they require remote handling, hot-cell work, shielding, and mechanical extraction. Platinum is rated “High” and is identified as readily available, subject to appropriate radiological controls. Comment by Akers, Holly: Double check [1: DOE Issues Expression of Interest for Surface Contaminated Nickel Technology | Department of Energy]

· Processing Requirements: Recovery of, cesium-137 chloride and lithium hydride will require significant purpose-built or modified processing systems capable of handling radiological materials and separating contaminants to reuse specifications. Platinum recovery will also require radiological controls because of its co-contaminants.

3.2 Infrastructure and Access

· The Oak Ridge Reservation is a secure, operational DOE complex with direct interstate highway and rail access.

· The lithium hydride shields are currently stored in RCRA-permitted Facility 7879 at ORNL and may remain there only until final transfer to a processing facility or facilities. Recovery planning therefore must coordinate characterization, authorization, and availability of the receiving processing facility before transfer.

· The sites possess extensive infrastructure, including robust utilities, support facilities, and a highly skilled workforce experienced in radiological and industrial operations.

· The presence of existing hot-cell facilities at ORNL (Building 3517) is a critical asset for the potential handling of highly radioactive materials like the cesium sources.

3.3 Economic Context

The more relevant economic comparator for these inventories is secondary recovery from complex, processed materials rather than primary ore grade. Consolidation at developed DOE facilities reduces mining and basic logistics requirements, but radiological processing and characterization remain significant cost drivers. Lithium hydride has strategic energy applications, while the smaller platinum inventory may offer a comparatively accessible precious-metal recovery opportunity. Any prospective offeror would need to conduct an independent economic assessment under current and projected market conditions.

Critical Mineral Resource Potential at the Portsmouth Site

U.S. Department of Energy, Office of Environmental Management

Executive Summary An estimated 1,100 tons (2.2 million pounds) of copper, 280 pounds of fluorine, and 3.1 grams of platinum have been identified in legacy inventories at the U.S. Department of Energy (DOE) Portsmouth Gaseous Diffusion Plant site in Ohio. These materials, byproducts of the site’s historical enrichment mission, represent a substantial opportunity to recover domestically sourced critical materials.

Based on initial characterization, the inventories are present in consolidated industrial forms, copper electrical windings. The bulk-metal contaminant profile is predominantly surficial uranium. Fluorine and copper are rated “Feasible,” and a process exists to extract the small platinum inventory.

These bounding estimates are based on site inventory data. The material is already mined, processed, and consolidated at a single, secure industrial site with access to critical infrastructure. The platinum inventory remains subject to the ownership and radiological constraints described below. The Portsmouth portfolio presents a near-term opportunity to transform a legacy environmental liability into a valuable national asset.

1. The Material

1.1 What Is There

The critical mineral inventories at the Portsmouth site are the material legacy of the facility’s decades of operation as a key part of the U.S. uranium enrichment complex. These are not raw ores but valuable processed materials recovered from decommissioned plant and support infrastructure. The inventories directly reflect their historical functions: copper was vital to electrical motor and distribution systems; fluorine was a key component in chemical and process operations; and a small platinum inventory is present at X-710.

1.2 Location

All identified inventories are consolidated within the controlled-access boundaries of the Portsmouth site in Pike County, Ohio. This single-site consolidation provides a major logistical and economic advantage for any potential recovery operation.

1.3 Material Distribution and Form

The materials exist in well-defined, recoverable forms that are conducive to industrial-scale handling and processing.

· Copper: Exists as high-purity electrical windings from large motors.

· Fluorine: Stored as a gas, implying containment within secure cylinders or tanks suitable for industrial gas handling.

· Platinum: A 3.1-gram quantity of solid material at PORTS X-710 with fixed radionuclide contaminants, mostly uranium.

2. Bounding Inventory and Grade Data

2.1 Summary by Material Type

The data summarized here are derived from internal DOE inventory collection forms. The information highlights a portfolio of large-scale materials with clear and established processing pathways. Comment by Akers, Holly: Kyle, should we change references throughout to EM since this is an EM EOI distinct from DOE EOIs Table 1. Bounding In-Place Inventory and Extractability Estimate for the Portsmouth Site

Important Caveat: The 3.1-gram platinum inventory at X-710 is the property of Centrus. The data call notes that transfer may be difficult because the material has fixed radionuclide contamination, mostly uranium, with a uranium-235 assay greater than 20 percent. This is an ownership and radiological-management constraint in addition to the technical extraction requirement.

3.1 Material Characteristics

· Contamination Profile: The primary contaminant for the bulk copper assets is surficial uranium, a profile that is conducive to established surface-decontamination techniques. Fluorine has no listed contaminants. The platinum inventory has fixed radionuclide contaminants, mostly uranium, and is subject to the ownership and assay constraint described above.

· Extractability and Recovery: The recovery outlook for the Portsmouth portfolio is strong. Copper and fluorine are rated “Feasible.” A process exists to extract platinum, although its availability is constrained by ownership and radiological conditions.

3.2 Infrastructure and Access

· The Portsmouth Site is a major, secure industrial complex with a full suite of supporting infrastructure, including heavy-haul roads and rail access.

· Decades of DOE operations have established robust utilities, security, and a local workforce with experience in complex industrial projects. This legacy infrastructure provides a substantial capital advantage for any new recovery operation.

3.3 Economic Context

The economic case for the Portsmouth inventories is materially de-risked by the specified processing technology and the draft third-party agreement for its largest asset. This technical pathway, combined with multi-million-pound inventories of copper, supports continued evaluation under current market conditions. The platinum inventory is technically extractable but subject to the separate ownership and radiological constraints described above.

4. Historical Precedent: Gaseous Diffusion Plant Metals Decommissioning and Recovery

4.1 Background

Historical decommissioning and asset-management programs at the gaseous diffusion plants generated and characterized large inventories of copper scrap.

4.2 Portsmouth as a Model for Technical Readiness

The historical programs for managing the GDP assets did more than simply quantify liabilities; they also involved extensive characterization to identify viable disposition paths. The Portsmouth nickel inventory is a prime example of this success.

· Grade and Scale: The precedent for successfully decontaminating and recycling surficially contaminated metals is well established. The scale of the Portsmouth inventories— over a thousand tons of valuable industrial metals—justifies the investment in a dedicated processing circuit, leveraging the economic advantages of a large, consolidated feedstock.

· Shifting Economic Viability: The combination of a known technical solution and favorable market conditions has brought the Portsmouth opportunity to the forefront. A process that may have been deemed uneconomic when scrap prices were low is now a highly compelling proposition. The Portsmouth portfolio is a testament to how long-term stewardship of legacy materials can create significant national assets when technology and market demand align.

Critical Mineral Resource Potential in the Moab UMTRA Tailings Stream Bounding Analysis for the Crescent Junction Disposal Cell U.S. Department of Energy, Office of Environmental Management Executive Summary The Moab Uranium Mill Tailings Remedial Action (UMTRA) material at Crescent Junction is one landfilled uranium mill tailings stream containing multiple co-located critical minerals. Approximately 16.2 million tons are currently disposed in the engineered cell, and approximately 1 million additional tons are expected through the project's tentative 2029 completion. The future material is expected to include off-pile and subpile radiologically contaminated material and may not have the same composition as the existing bulk tailings.

Vanadium is the most developed mineral-specific case. Historical, pre-relocation programs reported a mean grade of approximately 0.094% V2O5 (about 530 mg/kg elemental vanadium) across 58 Atlas Corporation samples; SRK Consulting's 2001 summary reported average vanadium concentrations of about 1,004 mg/kg in unconsolidated silt (slimes), 1,124 mg/kg in consolidated silt, 433 mg/kg in wet sand, and 211 mg/kg in dry sand; and the 1998 ORNL boring program reported values up to approximately 2,460 mg/kg in slime tailings. These data demonstrate vanadium occurrence and strong material variability, but they do not establish a current whole-cell average grade, contained vanadium tonnage, or recoverable mineral resource.

The data call identifies a suite of critical minerals of interest in the stream: aluminum, antimony, arsenic, beryllium, bismuth, boron, chromium, cobalt, copper, lithium, magnesium, manganese, nickel, tin, titanium, tungsten, vanadium, zinc, and zirconium. Rare earth elements have not been analyzed. Recovery readiness is constrained by the cell's UMTRCA/NRC status, the DOE land withdrawal from the Bureau of Land Management, an average Ra-226 activity of 477 pCi/g in 2012-2025 loadout measurements, incomplete mapping of higher-grade zones and disposed debris, the absence of site-specific metallurgical recovery testing, and the lack of processing infrastructure. This appendix is a screening-level bounding analysis.

1. The Material

1.1 Stream Definition and Origin

The Crescent Junction material is a single stream of uranium mill tailings and related contaminated material relocated from the former Atlas Corporation mill site near Moab, Utah. The original mill processed Colorado Plateau uranium-vanadium ore from 1956 through 1984 using acid-leach and alkaline-leach circuits, including a dedicated vanadium solvent-extraction process. The tailings therefore represent post-extraction residuals; for vanadium in particular, the material has already undergone primary recovery and should be evaluated as a secondary resource.

The stream was processed for transport and disposal during the ongoing UMTRA project but was not fully homogenized. It is a blended solid mass that includes fine-grained slimes, sands, limited super sacks, contaminated building debris, surcharge material, and subpile soils. The 16.2-million-ton figure is the current mass of the overall disposed stream, not the mass of any individual mineral.

1.2 Location and Accessibility

The engineered Crescent Junction disposal cell is in Grand County, Utah, approximately 31 miles north of Moab and adjacent to the I-70/US-191 interchange. An active Union Pacific Railroad mainline runs alongside the site and has been used at multi-million-ton scale to transport material from Moab to Crescent Junction. The remote, arid setting reduces nearby population and receptor concerns but must be considered in workforce, utility, and logistics planning.

The transportation corridors are proven, but the material is inside an NRC/UMTRCA-regulated disposal unit. Physical access for characterization, processing, or removal would require regulatory authorization and coordinated planning with DOE-EM and the U.S. Nuclear Regulatory Commission (NRC).

1.3 Physical Form and Distribution

The data call describes the approximate physical composition of the blended stream as follows:

Table 1. Approximate Composition of the Moab Tailings Stream

The bulk material is not containerized and is placed in an engineered cell approximately 4,400 feet long, 1,800 feet wide, and 50 feet in total depth; extending 25 feet above grade and 25 feet below grade. A limited number of super sacks and a significant but unquantified quantity of contaminated building debris are also present. The current cover is not yet fully complete and is planned to transition from the existing rock-armored configuration to an evapotranspiration cover system. No active liquid-containment vessels are present within the cell.

Distribution within the cell is not uniform. Based on disposal sequencing, higher-grade slime fractions are believed to be concentrated on the west side of the cell. The location and extent of super sacks and building debris have not been comprehensively mapped in the source documents, and those materials have not been separately characterized from the bulk tailings.

2. Bounding Inventory and Analytical Data

2.1 Stream Inventory

Table 2. Bounding Inventory and Stream Status

The quantities above describe the total material stream. They should not be interpreted as contained-mineral quantities.

2.2 Critical Mineral Availability

Table 3. Source-Supported Critical Mineral Availability

The SRK program directly analyzed a subset of the broader critical-mineral list, including aluminum, antimony, arsenic, beryllium, chromium, cobalt, copper, magnesium, manganese, nickel, tin, titanium, vanadium, zinc, and zirconium. The updated data call draws on the full historical source package for the broader list. Other co-located measured metals include barium, cadmium, calcium, iron, lead, mercury, molybdenum, selenium, silver, strontium, thallium, thorium, and uranium.

2.3 Vanadium Grade Indicators

Table 4. Historical Vanadium Analytical Indicators

mg/kg is approximately equivalent to parts per million by mass. All reported vanadium data above predate final relocation of the stream to Crescent Junction.

Important Caveat: The available grade data should not be multiplied across the 16.2-million-ton stream and presented as an established contained-vanadium inventory. The source programs are historical and limited relative to the scale of the cell; the stream is heterogeneous; higher-grade slimes are believed to be spatially concentrated; the incoming approximately 1 million tons are compositionally uncertain; and no site-specific recovery factor is available. No extractability rating is assigned in this appendix.

3. Key Considerations

3.1 Material Characteristics and Co-Contaminants

Radiological profile: Ra-226 averages 477 pCi/g in Radiological Control Program loadout measurements from 2012 through 2025. Fine-grained slime material has historically carried both the highest metals concentrations and the highest Ra-226 activity. Other measured radionuclides include gross alpha and beta activity, lead-210, polonium-210, radium-228, and thorium-230.

Chemical profile: Uranium, ammonia, and sulfate are expected process-related constituents. A broader suite of metals is also present. Post-relocation concentrations may differ from pre-disposal measurements because transport and disposal mixed the material without fully homogenizing it.

Speciation and extractability: Metals occur in multiple mineral phases, and solubility and extractability vary with pH, redox conditions, and element-specific mineralogy. Radiological management and mineral recovery are coupled engineering problems, particularly in the slime fraction.

3.2 Characterization and Recovery Readiness

No site-specific metallurgical test work is known to have been completed for vanadium or any other constituent in the Crescent Junction stream. The source package therefore supports occurrence screening, not process selection or recovery forecasting. A defensible next-stage evaluation would require independent sampling of current cell zones and material types, mapping and separate consideration of super sacks and building debris, characterization of incoming material, and laboratory testing to establish mineralogy, leachability or other process amenability, contaminant partitioning, and achievable product specifications.

REE analysis is a separate data gap. Any future analytical program intended to evaluate the full critical-mineral suite should include REEs explicitly rather than treating the historical omission as a negative result.

3.3 Regulatory Framework and Land Use

The disposal cell is regulated under UMTRCA and, after cover completion and NRC concurrence, is expected to operate under an NRC general license. Any disturbance of disposed material would require engagement and authorization from DOE-EM and the NRC. Regulatory approvals should be treated as a primary project schedule and cost driver.

The cell is located on land permanently withdrawn from the Bureau of Land Management to DOE for the remediation mission. Processing, reuse, or recovery outside that mission would likely require an additional land-use action, such as a withdrawal modification, authorization, or interagency agreement, separate from the UMTRCA/NRC approvals.

3.4 Infrastructure and Processing

Direct highway access and the adjacent active Union Pacific mainline are significant logistical assets. Those corridors were used for the ongoing bulk relocation program and demonstrate that large-scale material movement is possible. However, a recovery project would likely require new loadout and handling facilities, rail siding or track modifications, utilities, radiological controls, and processing infrastructure that have not been scoped in the source package.

The existing on-site infrastructure supports an active disposal mission, not mineral processing or reuse. Any heap leach, solvent-extraction, physical separation, or other recovery circuit would need to be newly established either at Crescent Junction, subject to regulatory and land-use approvals, or at an off-site facility.

4. Historical Processing Context and Recovery Implications

4.1 Original Atlas Mill Processing

The Atlas Corporation mill processed uranium-vanadium ore between 1956 and 1984 using both acid-leach and alkaline-leach circuits. Historical process descriptions identify reagents including sulfuric acid, sodium hydroxide, ammonia, and sodium chlorate, together with a dedicated vanadium solvent-extraction process. This history helps explain the mixed chemical suite that remains in the tailings and confirms that vanadium was an intentional recovery target during original milling.

4.2 Implications for Secondary Recovery

Because the material is post-extraction tailings, historical grades represent residual, partially depleted concentrations rather than untreated ore grades. The higher vanadium concentrations reported in slime material identify a logical characterization target, but the same fraction also carries the highest radiological burden and presents the most demanding material-handling conditions. Historical grade alone therefore cannot establish economic or technical recoverability.

The appropriate screening conclusion is that Crescent Junction contains a very large, single-location secondary material stream with a well-supported vanadium occurrence and a broader suite of co-located critical minerals. Vanadium should be retained as the lead quantified case, while the remaining minerals should be presented as identified constituents requiring additional characterization. Advancement beyond this bounding stage depends on current-cell sampling, mineralogical and metallurgical testing, a radiological management concept, and a viable regulatory and land-use pathway.

5. Key Source Documents

This integrated appendix uses the updated data call as the controlling description of the current Crescent Junction stream and uses the historical analytical programs as screening-level evidence of constituent occurrence and variability.

Lead Resource and Disposition Potential: DOE EM Nevada Program Inventory and Location Analysis U.S. Department of Energy, Office of Environmental Management

Executive Summary The U.S. Department of Energy (DOE) Office of Environmental Management (EM) Nevada Program has identified an inventory of legacy lead materials located at the Nevada National Security Site (NNSS) in Area 25. These materials, consisting of lead bricks and lead shot, were originally utilized as radiation shielding for legacy operations at the Engine Maintenance Assembly and Disassembly (EMAD) facility.

The currently identified inventory is planned for phased availability starting now. The immediately available inventory consists of 402 lead bricks that have been characterized as non-radiological and are ready for disposition as recyclable material. The projected future inventory includes additional variable-dimension lead bricks and lead shot presently integrated into existing structures or drums and is expected to be available by January 1, 2027.

Because on-site processing or reuse of this material is not feasible at the NNSS, the inventory is available for ground transportation and transfer to off-site facilities for processing, recycling, or reuse. Access to the material is subject to site permission and coordination with the DOE EM Nevada Program.

Current contract terms require the full lead inventory to be dispositioned prior to May 1, 2027. If no user is identified by this date, the material will be compliantly disposed of at NNSS.

1. The Material

1.1 Origin and Technical Context

The lead inventory at Area 25 was generated as a result of legacy operations at the Engine Maintenance Assembly and Disassembly (EMAD) facility. During active operations, high-purity lead was deployed in various physical configurations, predominantly as standardized shielding bricks and particulate shot, to protect personnel and sensitive instrumentation from radiation.

Following the cessation of legacy EMAD operations, these shielding materials were consolidated. Residual analytical profiles for some portions of the inventory, particularly the projected future materials, are currently pending final verification. However, the immediately available inventory of 402 lead bricks has been verified as non-radiological.

1.2 Location

The materials are situated within Area 25 of the Nevada National Security Site (NNSS), a secure federal reservation located in Nye County, Nevada.

· Site Access: The NNSS is a highly restricted security environment. Any physical access, inspection, or extraction of the material requires formal site permission, badging, and coordination with the DOE EM Nevada Program.

· Logistical Infrastructure: The site is accessible via established ground transportation corridors. Heavy haulage and standard ground freight represent the primary mechanisms for material egress.

1.3 Material Configuration and Storage

The inventory is divided into distinct physical forms and storage configurations based on its current operational status:

· Lead Bricks (Active Storage): The immediately available inventory consists of 402 lead bricks of standardized dimensions (). These are currently stacked and secured on two pallets.

· Lead Bricks (Active Storage and generating): Some variable-dimension bricks are in storage and the remaining variable-dimension bricks will continue to be generated, stored and projected for availability starting January 1, 2027, but no later than May 1, 2027.

· Lead Shot (In Structures/Drums): The lead shot inventory is slated for availability starting January 1, 2027, but no later than May 1, 2027. The material is currently stored in 30-gallon drums, with additional quantities remaining within legacy facility structures awaiting dismantling or recovery.

2. Inventory and Projections The following table details the current and projected inventory of lead materials at the EMAD facility, including planned transition timelines and radiological profiles.

Table 1. Lead Material Inventory and Disposition Schedule

3.1 Regulatory Framework

Any proposed transfer, transport, or reuse of the NNSS lead materials must comply with DOE Order requirements and NNSS site-security protocols.