EPA emails to TASSAL revealed

The scale and cause of the deaths of a large number of farmed salmon in February remain a mystery, with documents obtained by the ABC revealing the director of Tasmania's environmental watchdog assured the fish producer he "did not provide a detailed or complete response" to questions from the broadcaster.

Tassal has refused to provide details on the scale or cause of the deaths to the ABC.

At the time, the Environment Protection Authority (EPA) confirmed it had been notified by Tassal of increased mortality in five pens over three days, but also refused to provide details about the likely cause to the ABC.

Right to Information documents now show EPA director Wes Ford responded to an email from a Tassal employee two days after the story was published.