Robots tapped to siphon oil from sunken tanker

Send in the robots.

Where humans fear to tread, robots will — all in an effort to contain the worst oil spill in the Philippines, which now threatens the islands in Cebu province.

Petron Corp. will be using deep-sea submersible robots to siphon off nearly two million liters of bunker oil from the tanker that sank over half a kilometer from shore in the waters off Guimaras Island, company officials said yesterday.

Task Force Guimaras has warned that the oil slick is already moving towards the northern edge of Cebu, particularly towards scenic Bantayan Island, which lies 150 kilometers away from the site of the mishap.

Carlos Tan, Petron’s Health, Safety and Environment division chief, said the country’s largest oil refiner has tapped the services of the Japanese firm Fukada Salvage and Marine Works Co. Ltd. to pinpoint the exact location and position and undertake the salvaging of the M/T Solar I, which is estimated to have sunk to a depth of 640 meters or 2,100 feet.

"Even at the minimum of 500 meters, humans cannot work in those conditions. It will be purely robotics," Tan told a briefing at Malacañang. "We also want to determine what are the environmental conditions undersea like the temperature, water current. If the current is strong, work would take longer, it would be more difficult."

Tan said the intense pressure at the depths to which the robots will be sent can crush humans, even those protected by deep-sea diving suits.

He said the robots will be remotely controlled from a ship using computers and underwater cameras. The robot may even have to undertake the cutting and welding of the tanker’s hull, depending on the sunken vessel’s position on the seabed.

Tan said navigational maps indicated that the depth of the general area where the tanker sank ranges between 500 meters and two kilometers.

The Japanese team is expected to arrive in Guimaras on Saturday and start work on Sunday or Monday.

Tan said Fukada will first do a sonar sweep of the area covering several square kilometers to determine the exact location and position of the M/T Solar I — a procedure that will take a minimum of four to five days to complete.

Then the firm will use a submersible and remotely operated vehicle (ROV) connected to the salvage Petron’s tanker using a cable to allow experts to get a closer look at the vessel using cameras. The submersible is capable of reaching a depth of two kilometers, Tan said.

Petron chairman and chief executive officer Nicasio Alcantara said the ROV is equipped with state-of-the-art monitoring equipment that will provide the image of the tanker on the seabed.

Alcantara said 2,100 feet is the "greatest depth any oil tanker has ever been sunk" in recent memory.

He said it is believed that the tanker settled on soft mud, as the compartments containing the remaining 1.8 million liters of bunker oil apparently have not all ruptured, or the oil would have surfaced when the ship sank on Aug. 11.

Tan said the salvagers and Petron are anxious to know the exact position of the tanker, whether it is upright, upside down or lying on its side, as this would determine the magnitude of the work needed to siphon off the oil and bring the ship back to the surface.

"If it is upright, that means that the valve fittings are accessible and that would make our job easier. We can easily attach the hose for us to be able to suck the oil," he said.

If the tanker is upside down or on its side with its flanges or valves buried in the mud, the robots, he said, would have to do a "hot tap" where a hole would be drilled into the tanker hull to serve as an "exit point" for the oil.

"Once all the oil has been sucked out, we will float the vessel.

The contractor can do this," Tan said.

Defense Secretary Avelino Cruz, who as chairman of the National Disaster Coordinating Agency heads the task force, said Petron was asked to give daily reports of its progress in locating and salvaging the oil and tanker.

Alcantara said aerial surveys indicate that the oil leak has stopped.

However, he said the Petron has been coordinating with the Protection and Indemnity Club (P&I), which will pay for the task. P&I is the marine insurance firm of Sunshine Maritime, which owns the M/T Solar I. It covers third party liabilities and expenses arising from owning or operating ships as principals.

Petron, 40 percent of which is owned by the government, said in a statement that it "is not under any legal or contractual obligation to set aside economic aid or post bond to pay for clean up" because "it is the spiller who is primarily responsible."

Cruz said the statement was issued by Petron alone and that the ongoing investigation into the oil spill will determine the culpability of those involved in the incident.

"It’s too early to make conclusions but we assure the people and those concerned that the law will be applied equally," Cruz said.

Science Secretary Estrella Alabastro said the oil slick will reach Cebu in the coming several days if it is not contained.

Alabastro based her statement on the Department of Science and Technology’s "wave modeling" and simulations, as well as on weather forecasts.

She said experts estimate that the oil slick is moving at roughly one meter per second through the Guimaras Strait if the waves are calm.

Alabastro and Cruz however said the weather is expected to be calm in the area, at least until the weekend, and that the Philippine Coast Guard (PCG) and private ships are placing booms to block the moving oil slick, as are Guimaras residents near the area of the spill.