The investigation was commenced in mid-2016 and was seen as a test of new provisions in the state's Mining Act, similar to a character test.

This week a spokesman for the Resources Regulator said there was a process of "ongoing assessment" - and when asked to clarify this, revealed the investigation had been shelved after not enough evidence was found.

At some stage last year, the investigation ended without making a finding.

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No announcement was made to the public or to investors at the Australian Securities Exchange.

"The fit and proper investigation was converted to a process of ongoing assessment in 2019," the spokesman said.

"Investigations cannot continue indefinitely, This is because there was, and still is, insufficient evidence to support a finding that the company is not a fit and proper person."

And now the "ongoing basis" meant there would be no comment about he substance of the investigation.

"The NSW Resources Regulator is actively assessing, on an ongoing basis, Wollongong Coal's fitness to hold mining leases in NSW," the spokesman said. "Accordingly, it would be inappropriate to comment further."

Wollongong Coal has debts of almost a billion dollars, little revenue, a patchy record on environmental compliance, and its Wongawilli mine was closed down by the Regulator over safety concerns. Last year its auditor said debts far outstripped its assets.

Parent company Jindal Steel and Power has been embroiled in corruption allegations in India, as well accusations its security guards shot an anti-mine activist.

The development is a blow to environmentalists who have pushed for an "unfit" finding.

Lawyers at the Environmental Defenders Office, and the lobby group Lock the Gate, had called for a "fit and proper" investigation in the year before it commenced.

At the time, Wollongong Coal was in a trading halt after being suspended from the ASX for failing to lodge a preliminary company report.

Wollongong Coal is again suspended from the ASX after failing to adequately answer inquiries over whether it had overvalued its assets. The company has requested it be de-listed, saying the costs of maintaining an ASX listing were a burden, and the listing had not helped it raise money.

Do you know more? Email blangford@illawarramercury.com.au

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