New Zealand-based coal mining company Solid Energy has announced its proposal to permanently halt production at its unprofitable Huntly East Mine located north of Huntly township in Auckland.
In September, Solid Energy's creditors supported a plan to sell its assets over the next two-and-a-half years in a bid to extract maximum value.
Solid Energy chief executive Dan Clifford said: "The company said it would keep the mine going in a small way, at least-cost, because at that time the view of industry analysts was that the market would start recovering in a year or two.
"In fact the situation has continued to deteriorate and Huntly East Mine is now deeply unprofitable, costing in the order of $500,000 a month to keep open."
According to Solid Energy board chair Andy Coupe, the proposal to halt mining at Huntly East Mine would end almost 140 years of underground coal mining in the Huntly district.
"This individual mine has been in work for almost 40 years and over that time the working faces have moved further and further from its portals and deeper underground."
Huntly East Mine underwent restructuring in September 2013 and has been producing 100,000t of coal a year since then.
Solid Energy outlined its proposal to staff members and gave them ten days time to provide feedback based on which it plans to make a final decision by 22 October.
The mine began producing coal in 1978 and had peak production of 465,000t in the 2003/04 financial year.
The majority of Huntly East Mine's annual production is sold and sent by rail to New Zealand Steel's nearby Glenbrook mill.