Before the Stampede TLP currently under construction at the KOS yard in, could call Green Canyon Block 468 home, its anchor piles had to go beneath the hammer.
“As you may recall, 2015 was an eventful year for offshore installations,” said Chuck Cinotto, project manager, Stampede Hull, for Hess. “There were challenges caused by large loop currents during the execution of various deepwater projects, which were scheduled right before Stampede’s work. We watched the currents for many months and planned how we could effectively execute the work ahead when we went for the install.”
With the company’s early and open engagement with its trusted supplier Heerema Marine Contractors (HMC), planning for the piles installation at the Stampede development project was key to the success of the install.
“We work with the contractors to make sure we’re pointing in the same direction, working to solve the same problems,” Cinotto said. “We identified all the potential issues ahead of time and went a few steps forward and identified the mitigations. In a few instances we implemented the mitigations ahead of time.”
For Heerema, the work it is doing on the Stampede project is broken out into two phases. Lifting and installing the 500-short-ton piles was Phase 1 for the company. Phase 2 will be the lifting and installation of the 12 tendons, TLP facility itself and then pull-in of eight steel catenary risers.
“In the preparation phases we focus in depth on how we’re going to do the work, the risks and what countermeasures we need to put in place to mitigate those risks,” said Ewout Bastian, Stampede project manager for HMC. “We did it for Phase 1, and we are doing that at the moment for Phase 2. Procedures for Phase 2 are almost complete, and in them we go into a great amount of detail on how we will execute the work, including contingencies. For Phase 1 we had planned for it to last 15 to 16 days, and we did it in 12 in very challenging current conditions, so all preparations paid off.”
Mitigating the loop
The Loop Current, one of the fastest currents in the Atlantic Ocean, was identified as a primary issue for the Stampede team to work around. At the time of the installation the speed of the currents was twice as high as deemed normal in heavy-lift contracts, and the 16-day contract did not have that built in, just typical weather downtime. The Lean principle involved everyone on the team to determine solutions to a challenge and deliver results.
“Involving the workers and identifying the risks and mitigations as opposed to telling them what is going to happen is a big thing for Hess. It is actually something we have learned from Lean,” Cinotto said. “It was the workers that identified that the whole operation would come to a stop if an ROV goes down or if a subsea hammer goes down. These single points of failure were identified, and we implemented backups ahead of time to make sure there was no downtime in case something happened.”
Part of working on a collaborative team is understanding the risks creating discomfort or concern within the team. “We worked with the contractors on understanding these risks. We found that one was the ability of the ROVs to work in high current speeds, that there is risk of one of the two going down and then they’d be blind in some areas,” Whitaker said.
That is a risk that, according to Bastian, could bring operations to a standstill. “ROVs are our eyes and our hands subsea. If one of those breaks down, then we will be in a difficult spot,” he explained. “As part of our preparations, we discussed to what extent a breakdown would be acceptable. We carried three ROVs ourselves and of course try to prevent any breakdowns, but we can never rule it out completely.”
Hess hired a backup vessel from Tidewater with an ROV package onboard to have on standby and ready to go in Fourchon in case there was a breakdown.
“It was available in case it was required,” Bastian explained. “Fortunately, we didn’t need it in the end, but it clearly explains the sense of how we dealt with risk and how Hess was willing to work with us.”
The team’s ability to work within the difficult conditions it experienced was enhanced through the data it received from the current-monitoring vessel hired by Hess to keep an eye on the water and weather conditions.
“The real-time current-monitoring vessel was effective because each morning the superintendent would tell the vessel which way to go to watch the current, to see if it was flowing in or back out,” Cinotto said. “We had real-time measurements at the site, which is vital because all the predictions and analysis don’t really get you the actual at-the-site conditions, which is essential to know by the hour.”
It also freed the ROVs up to work up to the working limit without the fear of the units breaking down, he added.
“Because we had a spare, it allowed them to work in the high-current conditions,” he said.
The data coming from the current-monitoring vessel let the team know when the current was present onsite.
“If the current was there, we would move offsite and lower the pile down and then reposition over the site,” Cinotto said. “This is something the team identified ahead of time as potential mitigation. And once they encountered this, they didn’t need to call management and ask if it could be done as we had already given our approval to do so in advance.”
“It was great to see that all preparations and mitigations paid off.” Added Bastian, “We did not encounter a single hour of current standby despite very challenging loop current conditions at site.”
According to Cinotto, the cost to have an ROV on standby and the current-monitoring vessel was a wise investment. “We spent a little bit of money, but by doing so we were able to operate in a fairly robust offshore environment,” he said. “But by spending that money ahead of time to mitigate the risks, we were able to basically walk through the whole program—and that’s how we got it done in 12 days, which was a very good accomplishment.”
The four-day improvement in the actual vs. planned execution was arguably exponentially greater when one takes into account the fact that the 16-day contract did not have the potential impact of loop currents built in. Had the team not done everything they did in terms of planning and working to mitigate potential weaknesses, the schedule likely would have been much longer than the planned 16 days and would have involved substantial downtime.
Next steps
At press time the Stampede team found itself at the project halfway point. Installation of the subsea system and pipelines was underway, according to Whitaker.
“We’re drilling with the Ocean BlackLion, and we’ll be bringing in the Ocean BlackRhino [owned by Diamond Offshore Drilling Inc.] in the beginning of 2017. We’re going to be running two rig streams for this project. Right now it’s about the two rigs working together to deliver these deep wells. We’ve drilled one well so far, and we’re about to move into the first completion,” he said.
The surface facility is going through an integration phase at KOS, and if all goes as planned there, Whitaker hopes to see it heading out to the field in second-quarter 2017, where an extensive hookup and commissioning phase will be commenced.
“We’ve done really well getting ourselves to where we are today, pulling all the pieces together, and now it’s about a flawless execution. If we can do that, we’ll be delivering a project that I think will be a very successful project from the industry’s perspective,” he said. “But we have a hurricane season in 2017 to navigate, and we still potentially may see loop currents back next year, which we’ll have to address as well. So there are challenges to navigate between now and first oil in 2018,” Whitaker said, always emphasizing safety as the priority and repeating Hess’ primary strategic focus on its work: “Everyone, everywhere, every day, home safe.”
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