Updated October 01, 2012 15:33:17
Cyclone preparation is an annual routine in the state’s north.
Residents clear debris from the garden, refresh the first aid kit, ensure the candles are handy and batteries charged.
The approach of the wet season also has implications for the state’s oil and gas industry, which has billions of dollars worth of infrastructure and thousands of workers located in cyclone hot spots on the northern coast.
In 2007, Fortescue Metals Group learnt the hard way the destructive power of cyclones, when two workers were killed as they sheltered in a work camp flattened by Cyclone George.
So, how is industry able to co-exist with the often violent forces of nature in the north, and how is a cyclone simulator improving rig safety and pipeline stability?
Each year, an average of four to six cyclones cross the WA coast between the months of November and April.
On the wall of the Broome FESA operations room sits a map illustrating with red dots the coastal crossings recorded over the past century.
They’re clustered around the section of coast between Onslow and Broome that forms the hub of WA’s $107 billion a year oil and gas industry.
It’s an area dotted with offshore drilling rigs, export ships and workers camps.
WA Chamber of Minerals and Energy director Nicole Roocke says cyclones are a constant challenge for companies operating in the north.
“Most companies would anticipate a couple of days disruption per year in the North-West region as a result of adverse weather conditions,” she said.
“Industry is well drilled in these issues and always prepared, however, every cyclone presents its own challenges.”
The chamber says production has to be halted every time there is a cyclone threat in the area.
So, what happens on a drilling rig when the Bureau of Meteorology announces a tropical low has formed and a cyclone’s approaching?
Ships and floating oil platforms are often towed out to sea to try and avoid the cyclone’s path.
Ms Roocke says if that can’t be done, decisions have to be made about where workers will be safest.
“Well before a red alert is called, companies will tie down critical equipment, ensure employees are home safely and have had time to secure their property,” she said.
“(Or) if the facility is designed to handle the cyclone, critical staff may stay on the rig.”
While rig workers toil away in the north, it’s in Perth that the bulk of the work’s been done to improve the safety of rigs, including the platforms and pipelines, in the face of a cyclone.
At the University of WA, engineers have developed a cyclone simulator that allows them to test how the storms have an impact on the seabed.
Assistant Professor Scott Draper says the O-tube tests the water and sand pressure on a 20 metre length of pipe installed in a tank.
“Our main aim is understand the dynamic processes of how the sand moves around the pipe which previously has been ignored in stability calculations,” he said.
According to team leader, Liang Cheng, real-life cyclone conditions can be replicated almost perfectly within the tank.
“We actually can simulate the different storm conditions in different water types,” he said.
“So basically we can dial up any desirable storm we want and them simulate the response of the pipe.”
The research has already had tangible benefits for industry.
Professor Draper says one company came to them wanting to know how well a particular section of existing pipe would survive multiple cyclone strikes.
“We wanted to determine if it was going to be stable over the next 40 years, and the facility was used to make a prediction about that,” he said.
“That led to significant cost advantages for the operator involved.
“They were able to use the results from our O-tube experiment to make a prediction about what the pipeline would do and that saved them money on stabilisation costs.”
It’s hoped the improved understanding of how cyclones affect the seabed will also lead to breakthroughs in rig and platform design, and reduce the chances of them toppling over in a storm-front.
Professor Draper says the stability of the pipelines is critical as companies look to expand their operations in the north.
“At the moment, with the way the economy is moving, we’re seeing a significant amount of development on the North-West shelf,” he said.
“[There are] proposals for new offshore production facilities which will see more and more lengths of pipelines put on the seabed in the Pilbara region and perhaps towards the Kimberley coastline too.
“So, there’s definitely a need to improve our design practices and make sure that this increase in pipeline laying is safe.”
The Maritime Union represents hundreds of oil and gas workers in the north, and keeps a close eye on how companies manage the cyclone threat.
Assistant branch secretary Will Tracey says the companies usually know to get their employees out quickly.
“Generally they’ll fly them out to Perth and get them out quick, because as you go from yellow to blue to red alert, they’ll close the airports quite early,” he said.
“There’s no doubt it costly to evacuate a worksite, whether that be a rig or an island like Barrow Island but what cost do you put on loss of life?”
Mr Tracey says the deaths of the two Fortescue workers in 2007 shows how crucial good decision-making is in the days and hours before the storm hits.
In that case, the company was subject to harsh criticism and legal action for failing to evacuate its workers to safety.
In addition to the deaths, dozens of dongas were flattened and more than 20 people injured.
“The reality is on these resource projects, they’ve got an obligation to get people out of harm’s way,” he said.
As companies work to keep their staff safe, the UWA team is aiming to improve the stability of the infrastructure.
Professor Draper says the team is confident their work and the cyclone simulator will have a world-wide impact.
“There are design codes which are going to be updated, and we’ve been in discussion with the publisher to use the findings of our research to update and improve the design codes that are used internationally,” he said.
“I think that’s a massive breakthrough and I think where the far-reaching impact of our work can go.”Topics:
oil-and-gas, cyclone, research, broome-6725, karratha-6714 First posted October 01, 2012 15:30:31