Name of the Project
Ohmgebirge potash development.

Location
North-western extent of the South Harz sedimentary basin, about 30 km west of Sondershausen and 65 km north-west of the state capital, Erfurt, in Germany.

Project Owner/s
German mineral developer South Harz Potash.

Project Description
The 2024 prefeasibility study (PFS) demonstrated the technical and financial robustness of an existing shaft-access, underground mining operation, with a conventional cold-water leach and hot crystallisation process producing 930 000 t/y of premium muriate of potash (MoP), with total life-of-mine (LoM) production of 17.6-million tonnes. Peak MoP output is forecast at one-million tonnes a year in select higher ore-grade years.

The LoM schedule comprises total ore production of 90.1-million tonnes at an average diluted potassium oxide grade of 12.5% over an initial 19-year mine life.

Average throughput is estimated at 4.7-million tonnes a year.

Personnel and equipment access to the Ohmgebirge deposit will be through the currently operating Bernterode No 1 shaft. 

Requisite operating ventilation will be achieved using the Bernterode No 1 and Sollstedt shafts.

The crushing and dissolving process infrastructure will be positioned underground (in existing Sollstedt Haynrode mine voids), with the brine pumped to surface, and the evaporation process infrastructure being located proximate to the rail load-out area. 

Process residue will be treated through the underground backfill plant before being transferred and placed into existing Haynrode and future Ohmgebirge mine voids.

The mine plan for Ohmgebirge involves a combination of continuous mining and conventional drill-and-blast methods, tailored to the geological characteristics of the deposit.

Continuous miners are proposed for chevron-style panels in areas with low seam gradients and limited thickness, while benching in production wings is considered for thicker seams.

Conventional drill-and-blast methods are intended for square room-and-pillar mining blocks in areas with higher seam thickness and gradients, with ore haulage facilitated by a combination of equipment, including mobile conveyors; loaders, haulers and dumpers; and fixed conveyors. 

Mined material is transported to the underground crushers using fixed conveyors, and mined-out panels are backfilled hydraulically with waste material.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
The project’s pretax, real basis, ungeared net present value is estimated at $1.03-billion, at an 8% discount rate, and its internal rate of return at 17.8%.

Capital Expenditure
Preproduction capital expenditure is estimated at $1.15-billion.

Planned Start/End Date
Not stated.

Latest Developments
South Harz Potash has raised A$500 000 through the issue of 50-million fully paid ordinary shares to advance its Ohmgebirge potash project.

The placement includes A$149 867 in subscriptions from South Harz directors, with executive chairperson Len Jubber acquiring 6.49-million shares and director Rory Luff taking 7.49-million shares.

Proceeds from the placement will be directed towards securing a strategic development partner or cornerstone investor/s with the assistance of recently appointed financial adviser Cutfield Freeman & Co; finalising negotiations and executing a binding agreement with Deusa for the acquisition of the adjacent Sollstedt mine with substantial in-place infrastructure; investigating value engineering opportunities for the Ohmgebirge project that could provide a pathway to reduce the upfront preproduction capital requirement; and working capital for general, administrative and technical costs and additional costs associated with the capital raise.

Key Contracts, Suppliers and Consultants
None stated.

Contact Details for Project Information
South Harz Potash, tel +61 408 447 493 or email info@southharzpotash.com.