Sirius Minerals has selected Associated Mining Construction UK (AMC UK) and Hochtief Murphy Joint Venture (HMJV) as contractors for its North Yorkshire polyhalite project.
Polyhalite is a form of potash that is used in plant fertilisers.
A joint venture between Germany's Thyssen Schachtbau and Canada-based Thyssen Mining Construction, AMC will provide design services and be responsible for works relating to building of mine site development (MSD).
The MSD package works will include mine shaft construction and building of the mineral transport system (MTS).
As part of the initial phase of work, AMC will provide detailed front end engineering and design (FEED) process.
Sirius Minerals managing director and CEO Chris Fraser said: "This is the culmination of a huge amount of work by both the successful bidders and those that have been unsuccessful and we thank all of the groups involved for their efforts.
"We are delighted to now be moving forward with our selected partners towards the implementation of the project."
The company also selected Hochtief Murphy as contractor for the MTS.
Hochtief (UK) Construction and J Murphy & Sons joint venture HMJV will perform design and building of the MTS tunnel to link the mine with the materials handling facility at Teesside.
The initial phase will include a FEED process and a detailed geotech programme along the MTS route.
Work is expected to take more than 12 months to complete.
Sirius Minerals has been conducting the tendering process for these contracts since October 2014.
The process was carried out in parallel with the definitive feasibility study (DFS), which provided a benchmark to compare and analyse the contractors' designs, methodologies and cost estimates.
Image: The MSD package of work will cover shaft construction at the mine site. Photo: © Sirius Minerals.