More than 600 tons of explosive ammonium nitrate fertilizer also spilled from the Pacific Adventurer’s deck, sinking to the ocean floor in one of coastal Queensland’s worst-ever environmental disasters.

State Premier Anna Bligh declared the stretch of polluted coast a disaster zone as a navy mine-hunting ship searched for the 31 containers of lost chemicals.

The cargo of the potentially dangerous fertilizer was lost near a marine sanctuary. Some environmental experts warned that if the nutrient-rich chemical is released into the sea, it could feed a huge algae bloom that could cause a marine life catastrophe.

“It could potentially destroy local habitats. Highly territorial fish are at great risk as extreme concentrations could suffocate them.” said Mike Kingsford, James Cook University’s head of marine biology.

Five days after the spill, authorities said they had scraped the slick off of more than half of the affected beaches just north of the Queensland state capital, Brisbane.

But stormy weather then set in, blowing clean sand over some of the polluted beaches. The Australian Broadcasting Corp. reports that will force crews, who are mainly working by hand, to dig up two layers of sand to remove the oil.

Photo: Australian Maritime Safety Authority