IMPACT OF POLLUTION BY POTENTIAL OIL SPILLS ON COASTAL FACIES OF PULAU PANGKOR

Pulau Pangkor, an island off the western coast of Peninsular Malaysia is very
vulnerable to pollution by potential oil spills as it is located in the middle-eastern
sector of the Strait of Malacca, one of the world’s busiest maritime thoroughfares.
The coastal facies of Pulau Pangkor mainly comprise of sandy beaches and rocky
headlands on the western coast with a few mangrove swamps and mud flats on the
east coast. Grain size analyses of the beach sediments showed that, for most beaches,
the sand is coarser to the north and finer to the south, confirming that sediment
transport is from north to south. The composition of the beach sand also varies from
north to south, with a high proportion of carbonate particles (about 40%) in the north,
a mixture of carbonate particles and clastic sediments in the central coastline and
mainly quartz grains in the southern beaches of Pulau Pangkor. This pattern suggests
that there is very little sediment movement and a very slow dynamic sediment
transport around the island. The implications of these findings are that, should an oil
spill occur and reach the beaches of Pulau Pangkor, the oil would tend to settle on the
beaches and would not be removed or transported away by the slow, ineffective
longshore currents. To clean up the beaches, the spilled oil would have to be removed
manually or mechanically. The rate of penetration of oil into the beach sediments
varies according to the nature and grain size of the sedimentary facies. The rate of oil
penetration in carbonate beach sand is slower than in quartz beach sand as carbonates
become more easily oil-wet than clastics. In the event of an oil spill, oil slick
contamination on the beaches could be avoided by placing booms some distance off
the coastline. The booms can be anchored in the shallow marine area to block the
potential oil slicks and prevent them from reaching the beaches of Pulau Pangkor.
Additional mitigating measures include the use of dispersants or other methods to
contain or destroy the oil slicks before they reach the shoreline of Pulau Pangkor.