A BARGE working on the Western Basin Dredging and Disposal project dumped dredge spoil in the Great Barrier Reef World Heritage Area, breaching Commonwealth environmental approval conditions, in January this year.
The dumping of 730 cubic metres of dredge spoil within the World Heritage Area led to a $6600 fine for the Gladstone Ports Corporation.
As part of federal environmental conditions on the massive dredging project, spoil could only be dumped in approved areas, including the East Banks Sea Disposal Site.
But a spokeswoman for the Federal Environment department said the dumping of the spoil outside of the disposal site had contravened environmental approval conditions.
She also confirmed the spoil was dumped within the Great Barrier Reef World Heritage Area, although the department did not believe it resulted in any adverse impacts on the reef.
Western Basin Dredging and Disposal Project Manager Peter O'Sullivan confirmed the breach occurred on January 28 at 5.10am, after a split hopper barge was loaded with dredge spoil by backhoe dredge Razende Bol.
Mr O'Sullivan said after the loading of the spoil, the barge set sail for the disposal site, but "when confronted with rapidly deteriorating weather conditions", the captain decided an emergency dump was needed to safeguard the crew and vessel.
"This decision was based on the hydraulic pressure in the system controlling the opening of the split hopper being approximately 50bar above the nominal level of 250bar, indicating that an excessive amount of water had entered the hopper and increased the downward pressure on the hopper," he said.
Mr O'Sullivan said the barge was about 1.25 nautical miles from the approved disposal site when it was forced to dump the spoil.
He said there was 730 cubic metres of dredge spoil dumped, and the spoil was not potential acid sulphate soil.
The dredge contractor, Van Oord Dredging International, had since made changes to more accurately predict weather forecasts, including wave heights and strong winds.
"The dumping procedures and the use of the alternative sailing channel were reviewed to limit the risk of any reoccurrence," he said.
"At this time there are no backhoe dredge tug and barge combination barges working on the Western Basin Dredging and Disposal Project."
Mr O'Sullivan said the dump position was recorded and both state and federal environmental regulators were notified, before video cameras were towed through the area to show the dump had no impacts on marine plants or corals.
"A repeat survey was done to ensure material had not migrated out of the area. All these reports were provided to the regulators," he said.
The departmental spokeswoman said the payment of such fines "should not be taken as an admission of liability for contraventions of national environmental law".
The $6600 fine was the maximum amount the federal environment department can charge a company for breaches of approval conditions under the Environmental Protection, Biodiversity and Conservation Act.
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