Witnesses are being sought in relation to the grounding of a catamaran near Akaroa on Banks Peninsula.
The Black Cat Cruises catamaran was beached at Nīkau Palm Valley Bay, after it got into trouble on Saturday afternoon - requiring more than 40 people to be rescued.
Environment Canterbury (ECAN) said the first phase of the recovery operation - fully submerging the catamaran in deep water to prevent further damage - is expected to get underway today.
The second phase to remove it from the water, depended on the weather and safety requirements, it said.
ECAN said it was working with the Conservation Department, iwi, and Black Cat Cruises on the recovery and salvage, while the Transport Accident Investigation Commission said it would be investigating.
The commission's chief investigator, Louise Cook, said a team of investigators are in Akaroa, focusing on people's memories and digital information regarding the grounding in the first instance.
She said witnesses to the incident were being sought and anyone who was present on the day should go to the commission's website where they could submit information about it including photos and videos.
The inquiry could take between 12 months to two years to complete, Cook said.
Black Cat Cruises was approached for comment.
Longtime tourism operator, Tony Muir - who runs Coast Up Close - said the grounding hadn't put a hold on scenic tours, but the exclusion zone around it, had changed what's offered.
"Where they have it is right in the marine reserve, right at one of the highlights of the marine reserve.
"[On Sunday] afternoon we took a tour to the south, which is just fine as long as the weather conditions are fine... it's a beautiful trip.
"But... this is one of the jewels in the Akaroa crown, where this vessel has been positioned."
ECAN said the vessel was more significantly damaged than it anticipated and it was likely that all the fuel on board had leaked into the water.
It said the environment was coping, with oily sheens decreasing over time, and there were no signs of wildlife in distress.
A spokesperson said no fuel was able to be pumped out of the boat due to the nature of the incident.
"Most was discharged (likely in the early stages of the incident) due to the significant damage to the hull."
Muir said it "wasn't an ideal situation" but accidents happened and commended the crew for getting everyone off safely.
"It's [now] up to all the powers that be to lessen the impacts the best they can."
Following the near-sinking, Muir took his boat out on the water and helped with the clean-up.
"We went around and picked up a whole lot of rubbish, and plastic gloves, and puke bags and bits and pieces that had floated off it - we picked up quite a lot of that stuff just to get it out of the water."
Fellow tour operator, Roy Borelli of Fox II Sailing Adventures, said he also scooped up some of the Black Cat's debris.
He said his yacht, with 24 passengers on board, was one of the first on the scene on Saturday.
After a "wonderful sailing trip" where they'd been surrounded by dolphins, seeing the vessel was a bit of a shock.
"It was very... distressing seeing the boat listing. Because I've seen that boat almost every day that I've been working for the last 20 years.
"I know that boat. So, when you see it slowly sinking it's very, very upsetting."
He said he was one of many boats to offer assistance but ultimately wasn't needed, and believed the catamaran ran itself aground to prevent it from sinking further.
Borrelli said there was still plenty of wildlife outside of the exclusion zone.
"We don't know how long this is going to last, but it's still an amazing harbour, and we have so much to see.
"We typically see dolphins, penguins, seals, and albatross on many of our trips."
ECAN said the exclusion zone around the boat remained in place, and all non-response vessels must keep clear.
