Recently having completed its definitive feasibility study (DFS), Scarborough-based Sirius Minerals plc. now aims to raise $1.63 billion to finance the more risky construction elements, including the tunnels and shafts.

The study “represents the blueprint to bring this global fertilizer business into large-scale production,” says Chris Fraser, Sirius’ managing director and CEO. For the remaining $1.93 billion needed for the less-risky project completion work, Sirius plans to secure project financing or issue bonds. The company has lined up undisclosed contractors to bid for the construction, which is scheduled to last five years.

Since starting permitting negotiations with the North York Moors National Park Authority (NYMPA) in 2011, Sirius has completed its detailed project blueprint. San Francisco-based Bechtel Inc. managed the DFS, which was executed by a team that included Netherlands-based RoyalHaskoningDHV focusing on environmental and port aspects. Arup Group, London, covered the potash transportation tunnel system.

NYMPA approved the plan last summer in the face of local opposition. The planning committee conceded that the mine’s construction would cause “considerable harm” to the area. But the creation of an estimated 1,000 jobs was among the “long-term benefits for the local, regional and national economy” that swayed the planners to favor the scheme, according to the authority’s chief executive, Andy Wilson.

At the time, the National Trust, a large heritage and environmental protection body, “expressed serious concern and disappointment,” says Harry Bowell, regional director. “The [new] announcement of Sirius Minerals’ further plans does not change this view.”