The deposit is part of the Late Permian evaporite succession on the western edge of the Zechstein Basin, which represents multiple influxes and subsequent evaporation of seawater in a topographic low with restricted connection to the Zechstein Sea. The polyhalite sits within the EZ2 Fordon Evaporite sequence, a significant basin-infilling cycle. This sequence varies between 30 and 200 m thick across the project area, thickening to the east, towards the centre of the basin. The polyhalite appears to be formed by synsedimentary metasomatism or back-reaction of pre-existing sulphates; gypsum/anhydrite, with potassium and magnesium-enriched marine brines. The deposit is a stratiform sedimentary unit displaying significant lateral continuity. It is composed of two high grade seams: the Shelf Seam and the Basin Seam. The Shelf Seam exists on the basin margin and thickens in the central part of the project area before pinching out to the east. It is bound by intergrown halite anhydrite-polyhalite below and anhydrite above. The Basin Seam is deeper and bound by halite; it terminates against the base of the palaeo-ramp to the east and extends out to the west under the North Sea. On a smaller scale, the deposit is modelled as a series of laterally continuous units within the Shelf Seam, potentially representing variations in the sea level and depositional environment of the Zechstein Sea at the time. Three zones of high grade polyhalite are distinguished, separated by anhydrite-dominated bands.

The Woodsmith team is further developing the engineering to optimise the configuration of the project, recognising the multi-decade life of the mine. Particular attention is on those aspects identified at the outset of Anglo American’s ownership – namely, the sinking of the two main shafts, the development of the underground mining area, and the changes required to accommodate both increased production capacity and the more efficient and scalable mining method of using only continuous miners; such improvements will also require the installation of additional ventilation earlier in the development of the underground mining area.

At the Woodsmith Mine site, two deep shafts are being constructed to access the polyhalite in the centre of the mineral reserve: the production shaft reaching a depth of 1,594 metres and the service shaft reaching a depth of 1,565 metres. Once constructed the production shaft will be fitted out with two Blair multi-rope winders, each capable of hoisting 6.7 Mtpa of polyhalite ore for a combined capacity of 13 Mtpa. A third shaft, the Mineral Transport System (MTS) access shaft will also be constructed. The MTS access shaft is being constructed to facilitate construction of the MTS.

Woodsmith’s entire infrastructure has been planned and designed for minimal intrusion on this unique protected landscape. The mining area will be underground, and the mined ore will not be visible on surface, as it will be transported by conveyor throu ........

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