x Abu Dhabi, UAETuesday 25 July 2017

No two oil spills are the same

A dozen oil spills have reportedly fouled open water near Fujairah this year, keeping environmental clean-up crews busy.

An oil spill off the coast of Fujairah washes up on shore in February. Hundreds of oil tankers are anchored off the coast of the UAE.
An oil spill off the coast of Fujairah washes up on shore in February. Hundreds of oil tankers are anchored off the coast of the UAE.

A dozen oil spills have reportedly fouled open water near Fujairah this year, keeping environmental clean-up crews busy. With some slicks reaching beaches, residents are becoming increasingly aware of the problems, but few understand exactly what goes into the technology to contain and remove them. Alex Spence, the general manager for Seacor Environment Services Middle East, says that to appreciate the work of companies such as his, it is first necessary to understand how they categorise spills.

"We tend to classify spills into three categories - T1, T2, and T3," he says. In broad terms, a Tier 1 spill requires only a local response; Tier 2 might demand regional resources and Tier 3 necessitates international assistance. "A T1 ? that would be your first-strike response," he says. "That would be like if you have a very small fire in a room, picking up a fire extinguisher and putting it out."

A T2 is "if the whole room catches fire and you alert the fire brigade - and the T3 is if the whole building catches fire". A T2 spill can take anything from a couple of days to a week to deal with; a T3 can take months, or even years. There are, he says, three response options for dealing with oil spills: monitoring and surveillance for light spills, containment and recovery for larger incidents and a combination of containment and spraying of chemical dispersants for the most severe.

As most spills in the region involve fairly light oils and take place a significant distance from the shore, response teams will sometimes simply monitor the slick from aeroplanes or helicopters and wait for it to disperse naturally. "In this part of the world the water temperature itself is fairly high, so you get a lot of evaporation very, very quickly and a lot of dissolution and dissolving into the water column as well," he says. "It will biodegrade naturally in the ocean."

Wind, waves and currents also help to break up the oil, which is also degraded by the activities of bacteria and animal and plant life. Monitoring and surveillance, however, is an option only for lighter oils. All oils, hydrocarbons, are composed of different combinations of hydrogen and carbon atoms; the more carbon, the heavier the oil. Butane gas, for instance, has only four carbon atoms, whereas "there are 14 or 16 carbons in a chain for diesel, gasoline tends to be about five to 10, but crude oil is a much more complex combination", says Mr Spence. "The stuff that's on the road ? asphalt ? is really oil, and that has in excess of 40 carbons on a chain."

For spills for which observation is not enough and containment and recovery is necessary, clean-up firms use equipment such as oil booms ? floating barriers that contain slicks ? and other floating containment devices. Rotating "skimmers", such as those that were deployed after the Exxon Valdez spill of more than 10 million gallons in Alaskan waters in 1989, draw in oil mixed with water. Once the oil has been collected and separated, the company that caused the spill can buy it back it or sell it to the clean-up firm at a "slops reception and processing facility", says Abdullah al Sulaimani, manager of environmental affairs at the Fairdeal marine service.

Of course, time is of the essence, especially if sensitive shorelines are threatened. "The response and clean-up time as well as the size of the spill depends on how early we receive the alert," says Mr Sulaimani. In Fujairah and Jebel Ali, Seacor should have their equipment in the water within four to six hours of a T1 spill, says Mr Spence. "Less than six hours is good. For a T2, less than 12 to 24 hours."

There have, he says, been fewer major incidents in the past few years, although Seacor operates two T3 response centres ? one in Abu Dhabi and another on the east coast of the US. The third weapon in the armoury of the clean-up crews is chemical dispersant, which breaks down the oil in the sea. Typically, dispersant is deployed after skimming has captured as much oil as possible and is sprayed over the area to remove any remaining sheen from the water as quickly as possible.

"There are a lot of restrictions about the use of chemicals simply because, if used incorrectly, there is the potential to have significant impacts," says Mr Spence. "But when used correctly, they're one of the best response techniques available." While the first generation of dispersants were, in effect, industrial degreasers, the toxicity of the latest chemicals is much lower. "They dissolve the oil into very small droplets that are then moved down the water column and spread, and then there's natural but accelerated biodegration," says Mr Spence.

The Regional Organisation for the Protection of the Marine Environment (ROPME), to which GCC and Iranian environment industries belong, has formulated guidelines about the use of dispersants, which include restricting their use to within three nautical miles of the coastline and in areas only where the water is at least 10 metres deep. ROPME issued a list of approved chemicals in 2002 and its Code of Practice on Use of Oil Spill Dispersant can be found at www.ropme.net.

The UAE is a member of ROPME, but the use of dispersants is currently not covered by the country's laws. When all else fails - that is, if clean-up crews cannot prevent oil from getting to the coastline, either because of bad weather, lack of equipment or a poor response time - "then you end up with the de facto strategy - shoreline clean-up," says Mr Spence. Not only is that the most labour-intensive and time-consuming option, it is also the most expensive - both for the environment and for whoever is paying the bill.

Most of the spills in Fujairah can be classified as T1, but the threat of spills to sensitive areas remains ever present. "It's true that the standard of ships is getting better and there is more training, but a lot of the time spill response is about preparation and having an understanding about what you need to do in the time leading up to the response as well," says Mr Spence. "Timing is everything."

@Email:mkwong@thenational.ae