Buller's mayor wants Solid Energy to relocate most of its head office to Westport.
Garry Howard has written to Solid Energy's interim chairwoman, Pip Dunphy, urging the company to centralise near its coal mines.
Mr Howard said Westport was awash with rumours following the continued slide in export prices for coal. Unless prices recovered, there was an expectation Solid Energy would further restructure.
He and his council realised Solid Energy would have to respond commercially to protect its shareholder.
"However, we hold grave concerns about the effects on Westport."
Mr Howard said Solid Energy had given repeated assurances its future was as a dedicated mining company. His council endorsed that view and believed Solid Energy should, wherever possible, centralise its operations close to the point of production.
"We recognise that the company will have to retain some staff in Christchurch to manage the port operations and that it may be appropriate to retain a sales office near an international airport.
"However, we believe that the company could further reduce its costs by centralising all its other support and administration functions in Westport."
This approach had worked well for other West Coast mining companies and other high-profile success stories such as Westland Milk Products, Mr Howard said.
Solid Energy warned earlier this month that jobs would go, particularly at Stockton opencast mine, if international coal prices don't improve.
It has described local rumours that 150 to 200 Stockton jobs are on the line as "just speculation".
Solid Energy revealed last week that it still employs 81 at its Christchurch head office, despite assurances almost a year ago that it planned to reduce staffing there to 50.
It has not returned some head office functions to the regions, as planned. Nor has it found smaller, less expensive premises.
It is paying $16,833 for the two floors it rents at 15 Show Place Addington, but says that is considerably cheaper than the current Christchurch commercial rental market.
The Christchurch head office employed 206 people when Solid Energy hit the skids in July 2012. Overall company staffing has fallen from 1658 to 867.
- By Lee Scanlon of the Westport News
