The charges do not relate to events on the day of the eruption, or the rescue efforts.
WorkSafe alleges the Buttles failed with their due diligence duties, including failing to acquire and keep updated knowledge of work health and safety matters and failure to gain an adequate understanding of the hazards and risks associated with access to Whakaari.
Their company, Whakaari Management Ltd, is also alleged to have failed its duty to workers and tourists, including ensuring "an adequate means of evacuation from Whakaari".
WorkSafe alleges Institute of Geological and Nuclear Sciences failed to ensure the safety of pilots travelling to and remaining on the island.
At a case review hearing in the Auckland District Court on Thursday, Judge Evangelos Thomas opened proceedings by asking everyone to "take a moment to remember and acknowledge those who lost their lives and...those continuing to suffer".
Thomas discussed possible trial dates with WorkSafe's lawyer Kirsty McDonald QC and the defendants' legal counsel who all appeared in court by Zoom meeting links.
Thomas said setting a trial date now was a "priority" as nothing could happen going forward without it.
"I'd like it to be as early as possible in 2023. Anything in 2022 is unrealistic, we're looking at early 2023."
Thomas said a number of other legal matters, including a hearing to decide where the trial would take place, could not proceed until a date was settled.
Two of the 13 defence lawyers, said other lengthy court commitments in 2023 meant they could not immediately commit to court dates in early 2023.
Judge Thomas asked the lawyers to further discuss the matter and come back with options when the hearing resumed tomorrow.
The court heard that the National Emergency Management Agency has applied for its charge to be dismissed and a special hearing may take place on November 27.
WorkSafe was given a December 14 deadline to provide some further disclosure materials, including the list of prosecution witnesses, to the defendants' legal counsel.
