With the Jascon 25 pipelay crane vessel now at the Tubbataha reef, a spokesman of the United States Navy (USN) said yesterday salvage personnel will begin disassembling and removing the stricken Guardian minesweeper as soon as possible.
Lt. Frederick Martin, the USN Combined Task Unit (CTU) Guardian public affairs officer, gave the Manila Bulletin a summary of their salvage plan.
He stressed though that "individual steps, such as when to begin disassembling portions of the Guardian, are decisions made by the on-scene salvage experts based on weather and conditions at the site."
According to the USN officer, "Jascon 25, a dynamic positioning crane, has arrived in the area. This crane does not need to anchor, so it is expected to be able to operate where the other crane, Smit Borneo, could not. It also has a higher lifting capacity, needed to remove some sections of Guardian."
"Once the Jascon completes the Philippine Customs process and aligns and tests its dynamic positioning system, weather permitting, Smit salvage personnel will begin disassembling and removing the Guardian with the crane," he said.
In an email to the Manila Bulletin, Martin also provided a rough outline of the current salvage plan, but made it clear that "it will probably change as it is executed."
"It is important to understand that the plan is constantly changing and being refined as the operation continues. The salvage of USS Guardian is extremely complex, and is affected by a wide variety of factors, including weather and the continued structural degradation of Guardian itself," Martin explained.
Marine salvage is a dynamic operation and operational plans will need to be adjusted as circumstances change," he added.
When the dismantling of the Guardian begins, Martin said topside equipment will be removed first, followed by masts, funnel and other accessible equipment and portions of the ship.
"Throughout the process, protection of the environment and mitigation of environmental risk will be a significant consideration, alongside safety of personnel," he said.
"Next, once loose material has been removed, we expect to begin removing the ship's superstructure - the part of the ship above the main deck. Sections will be cut free and lifted with the Jascon crane, again with consideration of protecting the marine environment," Martin said.
Once the superstructure is removed, heavy machinery and equipment will be removed from inside the ship.
The USN spokesman said they have already removed the fuel and most of the other hazardous materials from the ship, and will monitor the removal of this equipment to ensure any remaining material is appropriately contained.
"Once the hull is mostly empty, we expect to begin to cut it into sections that can be secured and lifted. Our current estimate is that we will remove the hull in three sections. The bow and stern will be removed as intact pieces; however, the middle section will need to be removed in a piecemeal fashion as the structure lacks the strength to lift intact," he said.
The ship will be disassembled using a combination of hydraulic and pneumatic saws, grinders, cutters, and other equipment.
As equipment and sections of the ship are removed, they will be transferred to a barge or deck of the crane for further work.
The spokesman said, however, that they have not yet determined the final disposition of Guardian.
"Again, this entire plan is provisional, and based on what we know of the current conditions. As we conduct the operation, we may find we need to alter the plan, possibly significantly. We are working to remove the Guardian safely, while minimizing risk to the environment, and as quickly as those other considerations allow," said Martin.
He also reiterated that the salvage plan continues to emphasize safety and protection of the environment.
"Throughout the operation the salvage experts will alter procedures as necessary to protect personnel and the Tubbataha Reef ecosystem," stated USN spokesman.
Elena L. Aben | Manila Bulletin | February 18, 2013 | Article Link