SYDNEY (AP) — The government agency that oversees Australia’s Great Barrier Reef on Friday approved a plan to dump vast swathes of sediment on the reef as part of a major coal port expansion — a decision that environmentalists say will endanger one of the world’s most fragile ecosystems.

The federal government in December approved the expansion of the Abbot Point coal port in northern Queensland, which requires a massive dredging operation to make way for ships entering and exiting the port. About 3 million cubic meters (106 million cubic feet) of dredged mud will be dumped within the marine park under the plan.