Apex Energy's coal seam gas exploration plans in the northern Illawarra have been dealt a huge blow, with the expiry of a key licence meaning its drilling approval is now invalid.
The company and joint-venture partner Ormil Energy had approval to drill 16 exploratory boreholes across a large swathe of land in the northern Illawarra.
Fifteen of the boreholes were approved in September 2009, with a 16th added late last year.
The sites were spread across two exploration areas for which Apex had titles, known as petroleum exploration licences (PEL).
The northern title, PEL 444, covered the area around Helensburgh, Darkes Forest and Stanwell Park and included seven wells of different types.
The southern title, PEL 442, contained nine wells and covered a stretch of land from Clifton in the north to Dapto in the south, including most of suburban Wollongong.
PEL 442 has now expired, NSW Trade and Investment confirmed.
Apex lodged another application covering the same area in March, but faces competition from the NSW Aboriginal Land Council.
PEL 444 has also expired but remains in force after Apex lodged a renewal application.
However, the expiry of PEL 442 means that at present the firm will not be able to drill its boreholes.
The September 2009 approval for the first 15 wells said that drilling and operation could take place for three years from the date of approval or until the expiry of either PEL, whichever was sooner, unless otherwise agreed by the director-general of the Planning Department.
"This includes the six boreholes in PEL 444," a department spokesman said.
"To date, Apex has not applied for a modification of its conditions or sought the director-general's approval to enable drilling and operation.
"Any application for a modification will be transparently assessed and will involve full community engagement."
There is doubt about the status of the seventh well in PEL 444, approved separately late last year.
A NSW Trade and Investment spokeswoman said no exploration could occur without a title. She referred questions about the drilling to the Planning Department.
"PEL 444 - and associated approvals - remain in force until the renewal application is determined," she said.
Ormil Energy managing director Tom Fontaine did not confirm the expiry of the licence or the impact it had on the company's approval to drill boreholes.
He referred "anything related to permitting" to the department.
Stop CSG Illawarra's Jess Moore said the group saw the licence expiry as a victory "in so far as it removes the immediate threat".