A whistleblower at Origin Energy has filed an explosive legal action that alleges the company's former chief executive and current president of the Business Council of Australia Grant King engaged in a massive cover-up at the energy giant.

The 66-page amended statement of claim filed in the Federal Court on Monday alleges a management cover-up that includes serious non-compliance with regulations relating to safety and the environment, hundreds of wells in Australia and New Zealand that hadn't been maintained for more than 10 years, leaks of oil and gas, contaminations, a failure to inform regulators or the ASX of breaches and the material altering of reports to the board on risk and compliance issues.

Origin Energy former chief executive and current president of the Business Council of Australia Grant King. Credit:Janie Barrett

In at least one case the regulatory and legislative breaches were so serious they could have cost people their lives, the claim alleges. To fix some of the problems would have allegedly cost tens of millions of dollars.

The claimant is whistleblower, Sally McDow, a highly credentialled lawyer and senior compliance manager at Origin. She alleges a number of other whistleblowers exposed wrongdoing. She makes the claim as part of a case seeking compensation for workplace and other breaches.