The pair have vast, adjacent coal-mining rights on the plateau, north of Westport, to seek similar high-grade hard-coking coal deposits.
They signed an agreement this week to share some facilities, largely so as to avoid duplicating infrastructure development costs involving transport, site access, production facilities and water.
The main trade is Bathurst subsidiary Buller Coal Ltd will develop coal delivery from the plateau to a Westport railhead, which will be used at commercial rates by Solid Energy for a decade, while Solid Energy has delivered a transport agreement for Bathurst to rail 25%, or 500,000 tonnes, of coal 380km from Westport to Lyttelton Port of Christchurch.
Bathurst forecasts full production of 1.5 million tonnes of coal by December 2012. That coal is to be exported from Westport, which is redeveloping its storage and loading facilities.
Premium hard-coking coal is a key ingredient in steel manufacturing and has been commanding record prices due to demand from China and India. It was yesterday priced at $US315 ($NZ387) per tonne.
Craigs Investment Partners broker Peter McIntyre said the agreement was a "win-win" arrangement for the companies.
"The non-duplication of infrastructure assets is a big one. The collaboration is good for the sustainability of both companies, the coal resource and environmental factors like water use," Mr McIntyre said.
Bathurst, which entered the ASX-200 index early this month, has had a stellar share price run, rising from 75c at listing last December to $1.74 in early April. It later received an ASX "please explain" over a weekly 14% rise to $1.65 after entering the ASX-200.
Following yesterday's announcement, Bathurst shares surged more than 8.5% to trade around $1.40.
Bathurst's managing director Hamish Bohannan said the agreement would allow subsidiary Buller Coal to locate some of its facilities within areas covered by Solid Energy's mining licences on the plateau.
"Under particular circumstances and on commercial terms, the agreement enables Solid Energy to use any available spare capacity within Buller Coal's wash plant or coal transportation pipeline," he said.
The parties are working together to identify and implement arrangements to have sufficient water available for their respective Denniston operations.
Bathurst, which is claiming 225 jobs and annual wages of $30 million, has applied to the West Coast Regional Council and Buller District Council for 16 resource consents to mine, and is negotiating access and two concessions with the Department of Conservation.
