Bathurst's future looks anything but secure, with a paltry share price, cash flows consumed by costs, cash reserves running down and an uninspiring outlook on medium-term global coking coal prices.
Mr Bohannan joined Bathurst in 2008 and has been the main driver of the West Coast project near Westport, which once targeted the export of 4 million tonnes of premium hard coking coal.
However, environmental groups appealed the multiple consents Bathurst had received for the Denniston plateau project, which delayed start-up by two years, by which time global coking coal prices had tumbled, making extraction for export commercially unviable.
Mr Bohannan is to be replaced by chief operating officer Richard Tacon, who joined Bathurst in 2012.
Mr Bohannan was understood to be travelling yesterday, and could not be contacted.
Up until late 2011, then Australian-based Bathurst's entry to New Zealand was relatively seamless, raising $242 million and listing in November 2010 and purchasing separate tenements from the former L&M Group and Brookdale Assets; spending more than $300 million on the overall project to date.
Mr Bohannan has been the face of the company, enthusiastic about the future of coal mining on the West Coast, but was ultimately frustrated by New Zealand's consent process and the protracted legal opposition mounted by environmentalists.
Bathurst initially wanted Denniston operations to begin by mid-2012, but the legal consent issues added two years to the planned time frame, and by late 2013 global coal prices had begun to tank.
Undeterred, Mr Bohannan continued to push through recent plans to ready Bathurst to become operational around the Denniston plateau, saying as recently as late January he expected positive cash flows from Bathurst during the rest of the financial year.
Mr Bohannan had also noted in January the imminent departure of two co-executives would make a ''substantial impact'' on decreasing overheads.
From an all-time share price high of $1.74, Bathurst shares were down more than 80% on two years ago and were yesterday trading around 3.1c - barely a market capitalisation of $30 million.
Bathurst chairman Malcolm Macpherson yesterday reiterated Bathurst's ongoing business efficiency review has resulted in operational restructuring throughout the company's sites during the past year.
''In line with this process, and with the full-scale development of the flagship Escarpment mine project [on the Denniston plateau] being put on hold, Mr Bohannan has now decided to seek a fresh challenge,'' he said in a statement.
He said Mr Bohannan had played a critical role building and implementing the strategic growth of Bathurst in New Zealand.
At full capacity Bathurst was expected to employ more than 400, but fewer than 100 are on the payroll and the management team has been slashed from seven to three in recent months.
Bathurst has been generating some cash flow from its three South Island domestic mines, for local industrial use, but global coking coal prices are still below $US120 per tonne, the price which, if sustained, could prompt mining to begin profitably.
For its six months trading to December, Bathurst's total domestic-generated sales were down 3% to $26.4 million, but a more than doubling of other expenses, including more than $3 million in depreciation, saw last year's $8.51 million after-tax profit slashed to a $7.17 million loss.
As at December, Bathurst retained $5.9 million cash in hand.
