Mining Intelligence and News
United States

Lance Mine

Click for more information

Categories

Summary

Mine TypeIn-Situ
StatusActive
Commodities
  • Uranium
Mining Method
  • Solution mining
Production Start... Lock
Mine Life... Lock
SnapshotPeninsula’s flagship Lance Project ranks among the largest uranium projects in the United States by size and scale.

On December 19, 2024, Peninsula Energy announced the restart of uranium production at Lance, with operations resuming on December 18 in selected areas of Mine Unit 1 (MU-1) following a five-year hiatus. The restart employs low-pH in-situ recovery (ISR) technology, with initial production directed to the Phase 1 ion exchange system.

Uranium inventory being captured on IX resin at Phase 1 satellite plant until Phase 2 plant becomes operational.

As of 16 June 2025, construction of the Phase II Central Processing Plant is nearing completion, with hot commissioning scheduled for later in June.

Owners

SourceSource
CompanyInterestOwnership
Peninsula Energy Ltd. 100 % Indirect
Strata Energy, Inc. (operator) 100 % Direct
Peninsula Energy Ltd. holds 100% ownership of the Lance Project, which is operated through Peninsula's wholly owned subsidiary, Strata Energy Inc.

Contractors

Lock

- subscription is required.

Deposit type

  • Sandstone hosted

Summary:

The deposits are epigenetic uranium roll-fronts. The Lance Project is located on the eastern periphery of the Powder River structural basin and on the western margin of the Black Hills Uplift. Geologic strata in the vicinity of the Lance Project comprise Cretaceous marine and marginal marine fluvial sediments belonging successively to the Pierre Shale Formation, Fox Hills Formation and Lance Formation within the Lance Project. Mineralization primarily occurs within the upper Fox Hills sandstone, although in localized areas there is some mineralization within the overlying Lower Lance sandstone. All the formations of interest (Lance, Fox Hills, Pierre) outcrop immediately east of the Lance Project at the Black Hills Monocline. The monoclinal feature caused a steepening of the dip (85°to 90°) to the east of the Lance Project, which resulted in the formations outcropping more abruptly than the 1° to 2° regional dip to the west.

Roll front deposits result from oxidizing groundwater migrating down gradient through regionally reduced sediments. Subsequent geochemical cells, produced by migrating groundwater, formed deposits through a dynamic process of oxidation, dissolution, transportation, reduction, and precipitation of uranium.

Previous geological modelling of the extensive downhole geophysical data has accurately defined the impermeable shales and mudstones that form the confining seals to the mineralised aquifers.

Geological interpretation
The sandstones that make up the various formations of the Lance uranium deposits were all deposited in a fluvialmarine environment as channel sand or overbank deposits. They are characterized by fining-upward sequences comprising thick, laterally persistent, tabular, sheet-like sandstones.

Uranium mineralization occurs preferentially in the sand units of the Fox Hills or lower Lance Formations, which were deposited under more reducing conditions. Within the sandstone, uranium distribution is controlled by basin- ward migration of chemical fronts that represent the interface between reduced and oxidized sandstone. The primary uranium-bearing minerals are uraninite, uranophane, autunite, or coffinite representing tetravalent and hexavalent forms in the reduced zone with H2S and organic carbon acting as the reducing agent to precipitate uranium.

Vanadium and, to a much lesser degree, selenium and arsenic are the main associated elements.

Dimensions
In plan-view, the deposits range from several hundred meters long to over 9,000 metres long with widths of between 10 metres and 80 metres wide. The high-grade cores of the roll fronts within the deposit range from about 2 metres to 10 meters wide and average 1.5 metres thick in section.

Mineralization occurs in several horizons with a total mineralized package of up to 60m in thickness.

Host sandstones dip at -1° to -2° towards the west and southwest.

Reserves

Lock

- subscription is required.

Mining Methods

Lock

- subscription is required.

Heavy Mobile Equipment

Fleet data has not been reported.

Comminution

Crushers and Mills

Milling equipment has not been reported.

Processing

Lock

- subscription is required.

Commodity Production

CommodityProductUnitsAvg. Annual (Projected)LOM (Projected)

Production Costs

Commodity production costs have not been reported.

Personnel

Mine Management

Job TitleNameProfileRef. Date
....................... Subscription required ....................... Subscription required Subscription required Jun 25, 2025
....................... Subscription required ....................... Subscription required Subscription required Jun 25, 2025
....................... Subscription required ....................... Subscription required Subscription required Jun 25, 2025
....................... Subscription required ....................... Subscription required Subscription required Jun 25, 2025

Workforce

Aerial view:

Lock

- subscription is required.