The NSW Resources Regulator has confirmed it is investigating the company, which is without an operating mine since the shutdown.

Alarmingly for the miner, the Regulator has also issued a legal notice seeking financial records and information about Wollongong Coal's ability to meet its obligations under the law.

This relates to information on debt restructure agreements, and demands from the corporate regulator ASIC for justification of the company's claims about how much its mines are worth.

"Following ongoing issues at Wongawilli Mine [the] NSW Resources Regulator has begun an investigation into the mine's compliance with the Workplace Health and Safety Act," a Regulator spokesman said.

"The stop work order follows the Regulator issuing four separate Section 195 prohibition notices on the mine's operators, in relation to significant safety issues identified at the mine.

"Additionally, the Regulator is continuing its investigations into whether the operator remains Fit and Proper under the provisions in the Mining Act."

This week Wollongong Coal has also had to announce the departure of its most recently appointed director, Devendra Vyas. 

Mr Vyas, an experienced mining manager, had held his position for less than five months. He had been the representative of parent company Jindal Steel and Power.

Wollongong Coal did not explain why Mr Vyas left and did not respond to requests for comment on the issue.

His departure was announced on April 1.