SOSRC

SINGAPORE OIL SPILLRESPONSE CENTRE
A subsidiary of SembCorp Logistics Ltd.

ISO CERT. NO. 907724“Natuna Sea” Incident and the Response to the Spill
Case History

Early in the morning of Tuesday 3rd October 2000 the 81,000 tonne tanker“Natuna Sea” was sailing eastbound through the Singapore Straits, preparing to
make a stop in Singapore for taking on fuel oil bunkers. She had loaded her cargoof around 70,000 tonnes of Nile Blend crude oil at Al Bashayer Marine Terminalin Sudan and her ultimate destination was a port in China, where the full cargo wasto be discharged.
The ship is one of a large fleet of Tankers operated by a Singapore based Ship
Management Company and had been in service for some 20 years under various
different Companies and names. Despite her age, she was in good condition,
having been well looked after by her present owners and her mainly Indianofficers and crew.
The cargo she was carrying, Nile Blend crude oil, is unusual in several respects. It
was one of the first exports of oil from a new oil field in Sudan and is aparticularly heavy and waxy crude, with a pour point of around 330 Celcius. Thiswould mean that if it spilled into the sea it would most likely nearly solidify,Telephone : (+65) 2650177 (+65) 6639209 (+65) 6639217 (+65) 9 -6715644 (Handphone)
Fax Number : (+65) 2644190 (Operations Room)(+65) 96765529 (Handphone Fax)
59,Shipyard Road, Jurong, Singapore 628143
E-Mail : sosrc@sembcorp.com.sg
Website : www.semco.com.sg

SOSRCSINGAPORE OIL SPILLRESPONSE CENTRE
A subsidiary of SembCorp Logistics Ltd.

because in most places around the world the sea temperature is cooler than thepour point of the oil. This oil is also unusual in that it also has a high sedimentcontent and needs to be carried in Tankers at quite a high temperature in order toprevent the sediments from settling out.
As the Natuna Sea was approaching the narrowest point of the Singapore Strait she
was having to make alterations of her course in order to pass clear of other vessels
and these alterations had taken her to the south side of the eastbound traffic lane.
Unfortunately, in this area the are often very strong currents of up to 5 knots andthese currents left very little time for the vessel to be manoevered clear of therocks of Batu Berhanti. This is an area of very shallow water on the Indonesianside of the channel, opposite Singapore’s Sentosa Island, which is notorious forcatching out unwary navigators and has become the graveyard of numerous
vessels. On the 3rd October 2000 during her fateful passage through the Straits, theNatuna Sea also became caught by the currents and ran hard aground on to therocks, causing serious damage to the Ship’s cargo tanks and resulting in an
immediate and major oil spill. On the bottom of the Ships hull, many of the centre

Fax Number : (+65) 2644190 (Operations Room)
Telephone : (+65) 2650177

E-Mail sosrc@sembcorp.com.sg(+65) 6639209 (+65) 6639217 (+65) 9-6715644 (H/P)
Shipyard Road, Jurong, Singapore 628143

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SOSRCSINGAPORE OIL SPILLRESPONSE CENTRE
A subsidiary of SembCorp Logistics Ltd.

and starboard side cargo tanks had been torn open and an estimate was later madethat some 7000 tonnes of oil had spilled out into the sea.
Immediately the response swung into action in an effort to deal with the oil as
effectively as possible, as well as minimise the possibility of any further leakage
from the ship. Extensive chemical dispersant spraying operations were carried out,
including the use of an airborne dispersant delivery system, and oil booms weredeployed around the ship to try and contain the oil that was still leaking out of thedamaged cargo tanks. Chemical dispersant spraying was also carried out fromnumerous vessels, including four belonging to Semco Salvage & Marine, theparent company of Singapore Oil Spill Response Centre (SOSRC), although it wasquickly found that the dispersant was only really effective where the oil was still
fresh. Oil recovery operations were also mounted, again close by to the ship
where they could be most effective, although by the end of the first day of theincident there were several large patches of oil moving up and down the Singapore
Strait with each change of tide, threatening both the Indonesian and Singapore
shorelines with major pollution.

Fax Number : (+65) 2644190 (Operations Room)
Telephone : (+65) 2650177

E-Mail sosrc@sembcorp.com.sg(+65) 6639209 (+65) 6639217 (+65) 9-6715644 (H/P)
Shipyard Road, Jurong, Singapore 628143

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SOSRCSINGAPORE OIL SPILLRESPONSE CENTRE
A subsidiary of SembCorp Logistics Ltd.

It was quickly becoming obvious this was a major oil spill incident and substantial
resources were urgently needed, so the ship’s owner contacted Petroleum
Association of Japan, with a request to utilise PAJ’s stockpile of equipment storedand maintained in Singapore by SOSRC. The lending Agreement was quickly
signed and the stockpile was rapidly sent to location, adding substantially to thelarge quantity of equipment already deployed by SOSRC and various otherorganisations.
The spilled oil was by now rapidly forming large patches of semi solidified oil,many of them concentrated in the waters to the south east of Singapore. Although
there were many oil patches, it proved relatively easy to contain them in booms bymanoevering the boom deployment vessels in the same direction as the current andslowly overtaking the slicks. However, keeping the slicks contained and in one
position was far more difficult due to the strong currents, and on several occasions
oil was successfully boomed, only to be lost again when the tide changed and thecurrent became strong. It is difficult to be certain, because one patch of oil looks
very much the same as another, but it is very likely that some oil slicks lost to thecurrent after being contained in booms were caught again when they returned at

Fax Number : (+65) 2644190 (Operations Room)
Telephone : (+65) 2650177

E-Mail sosrc@sembcorp.com.sg(+65) 6639209 (+65) 6639217 (+65) 9-6715644 (H/P)
Shipyard Road, Jurong, Singapore 628143

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SOSRCSINGAPORE OIL SPILLRESPONSE CENTRE
A subsidiary of SembCorp Logistics Ltd.

the next change of tide! Eventually it was found that the only option was tocapture a patch of oil in a boom and then allow the whole formation of boom,
vessels and patch of oil to drift with the tide, only manoevering when necessary to
avoid the shipping lanes or shallow water areas.
Of course, having perfected the technique of containing and keeping the oil, it thenbecame a matter of urgency to recover and temporarily store it, before it would be
lost again. As always, this brought with it a whole range of problems, not least ofwhich was how to recover the by now very viscous oil, and how to temporarily
store it nearby to the operational area.

Eventually the oil patches weresuccessfully brought up to crane and storage barges for recovery operations to getunder way, although this also proved to be very difficult with many types ofskimmer being tried before an effective solution was found. In addition to being
very thick, the oil had also collected large amounts of debris during its time in thewater, including tree branches, seaweed, coconut husks, garbage, oil drums andeven an old refrigerator on one occasion! Many skimmers rely on oil flowing into
them as they operate, but these slicks would not flow at all, having formed analmost solid mass. The only solution was to use mechanical grab type skimmers

Fax Number : (+65) 2644190 (Operations Room)
Telephone : (+65) 2650177

E-Mail sosrc@sembcorp.com.sg(+65) 6639209 (+65) 6639217 (+65) 9-6715644 (H/P)
Shipyard Road, Jurong, Singapore 628143

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SOSRCSINGAPORE OIL SPILLRESPONSE CENTRE
A subsidiary of SembCorp Logistics Ltd.

and, although slow, the oil was slowly but surely recovered over several days foreach slick contained in booms.
The problem of storage was eventually solved by using sand barges, with their sidepanels sealed to prevent leakage, and the oil being recovered and dumped directly
on to the barge’s deck, together with all the other garbage. Once safely stored onthese barges, a small army of Indonesian labourers set to work to transfer all ofwhat had been recovered into leak-proof plastic bags, for eventual disposal ashore
into approved landfill sites. In all, it is estimated that around 500 to 700 tonnes
was eventually recovered, or approximately 7% to 10% of what was spilled. The
rest mostly stranded on the shorelines of the nearby Indonesian islands andSingapore’s Sentosa island.
Although these shores were impacted by quite a large quantity of oil, it proved tobe relatively easy to remove, due to the viscosity of the oil being so high that it
stayed on the top of the sand, rather than penetrating into it. Again, PAJ played its
part and made a substantial contribution to the clean up effort, with the delegatesof the annual PAJ training course that had been scheduled for the same time
getting to work with shovels and waste bags. As always on such a course, there

Fax Number : (+65) 2644190 (Operations Room)
Telephone : (+65) 2650177

E-Mail sosrc@sembcorp.com.sg(+65) 6639209 (+65) 6639217 (+65) 9-6715644 (H/P)
Shipyard Road, Jurong, Singapore 628143

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SOSRCSINGAPORE OIL SPILLRESPONSE CENTREA subsidiary of SembCorp Logistics Ltd.

were to have been a series of practical exercises included in the schedule, so
instead of postponing the course it was decided to hold it anyway. Of course, if
there is the opportunity to participate in the real thing it is much more beneficial
than having to imagine exercise scenarios, so full advantage of the situation wastaken with the delegates carrying out real boom and skimmer deployments at thespill clean up location.

In the true spirit of International co-operation, thedelegates from Japan worked alongside the local Malays and Singaporeans andbetween them managed to completely clean up one of the worst contaminatedbeaches, all in one afternoon!

The gratitude of the people of Singapore is once again extended to Petroleum
Association of Japan for its assistance in minimising the damage from what could
have easily been a major environmental disaster.

Chris Richards
Oil Spill Services Manager
Singapore Oil Spill Response Centre

Fax Number : (+65) 2644190 (Operations Room)
Telephone : (+65) 2650177

E-Mail sosrc@sembcorp.com.sg(+65) 6639209 (+65) 6639217 (+65) 9-6715644 (H/P)
Shipyard Road, Jurong, Singapore 628143

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