27 Oct 2021

West Coast salvage operation removes shipwreck contaminants

7:21 pm on 27 October 2021

Almost three months after a fishing boat ran aground on the West Coast, a complex salvage operation to recover potential contaminants has been completed.

Fishing vessel the FV Mistral ran aground at Kaihoka Point near Farewell Spit at the top of the South Island in July, with concerns heavy oil, hydraulic fluid and diesel fuel could contaminate the remote coastline.

Fishing vessel the FV Mistral ran aground at Kaihoka Point near Farewell Spit at the top of the South Island in July, with concerns heavy oil, hydraulic fluid and diesel fuel could contaminate the remote coastline. Photo: Supplied / Tasman District Council

In the early hours of 14 July, the skipper of the FV Mistral put out a distress call, having gotten into trouble off the West Coast near Farewell Spit at the top of the South Island.

The wet and uninjured skipper was airlifted to safety in the early hours of the morning by the Nelson Marlborough Rescue Helicopter.

Tasman District Council's regulatory services manager Adrian Humphries said the wreck site was difficult to access and poor weather conditions made the salvage difficult.

There were concerns that heavy oil, hydraulic fluid and diesel fuel could leak from the boat and contaminate the remote coastline, but the Mistral was upright and in relatively good condition.

As the on scene commander, Humphries was responsible for ensuring potential pollution was contained but as the weather deteriorated, the salvage had to be put on hold.

"We had to pull the spill team out and leave the local farmer to monitor the situation for us."

Humphries said after discussions with the insurance company, a complete recovery of the vessel was deemed too costly and nearly impossible.

It took nearly three months to salvage hazardous material from the remote wreck site, which was a two-kilometre quad bike ride from the nearest track then a 70-metre cliff climb.

It took nearly three months to salvage hazardous material from the remote wreck site, which was a two-kilometre quad bike ride from the nearest track then a 70-metre cliff climb. Photo: Supplied / Tasman District Council

Access to the wreck site was extremely difficult and involved a two-kilometre quad bike ride from the nearest track, then a 70-metre cliff climb.

"We settled on a plan to use helicopters to recover the dangerous debris, however this could only be done when the tides were right. We had a window of two hours either side of low tide to get the work done safely."

The first clear weather window was 10 days after the grounding.

Seven planned missions were thwarted by bad weather, but three were successful.

"We flew in specialised pumping equipment and water was removed from the hull, then more than 200 litres of heavy oil and hydraulic fluid were drained from tanks on the wreck and removed without incident."

Over the next two successful helicopter missions around eight tonnes of navigational hazards were plucked off the Mistral.

Fortunately, there was no apparent environmental impact and despite the extreme working conditions, no injuries.

The recovery cost reached close to $50,000 and was met by the insurance company.

Humphries said although Tasman District Council took the lead, the operation drew on expertise, guidance and cooperation from numerous agencies and individuals.

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