DISTRIBUTION AND WEATHERING OF OIL FROM THE IRAQ-KUWAIT CONFLICT OIL SPILL WITHIN INTERTIDAL HABITATS—TWO YEARS LATER

Abstract

ABSTRACT The heavily oiled coastal bays of Dafi and Musallamiyah on the Saudi Arabian coast were surveyed in 1992 and again in 1993, two years after the Iraq-Kuwait conflict oil spill. All habitat types showed little improvement or recovery from their condition one year earlier. Oil on the exposed outer beaches was beginning to form asphalt pavements, much like the ones still present from the 1983 Nowruz spill. Moderately exposed sand flats with bars showed no change in the distribution of surface oil; but in some areas, the subsurface oil migrated deeper, up to twice the depths in 1992. The heavy surface oil on moderately exposed sand flats was hardening into incipient pavements, which are sealing off the heavy subsurface oil from natural removal and weathering processes. Sheltered habitats showed even less improvement, with contamination likely to remain for decades. Factors contributing to the long-term persistence of oil in these intertidal habitats include the initial, heavy oil loading; deep penetration into porous sand substrates, even on the lower intertidal zone; deep penetration into animal burrows in muddy sediments; and subsequent formation of extensive asphalt pavements, which have sealed the subsurface oil from physical removal processes and slowed chemical weathering.