"In these 83 containers, there is just about everything that gets imported into this country. We've had chips, lollies, whitegoods, kitchen cabinets, even whole kitchen suites in these containers," Mr Mitchell said.
Damaged containers on the cargo ship YM Efficiency, which arrived at Port Botany in Sydney on Wednesday.
Photo: AAPMost of the lost shipping containers are believed to have sunk to the ocean floor, he said.
"It is not uncommon for containers to fall off ships, unfortunately. Around 10,000 get lost [worldwide] every year," he said.
"Certainly getting 83 in such a small location so close to the coast is something we haven't seen in NSW in a long time."
About 100 people continued to work on cleaning up the state's coastline on Wednesday, with assistance from divers and boats.
Clean up contractor Lucus Towell clears debris from the beach at Hawks Nest near Port Stephens, north of Newcastle, on Tuesday.
Photo: AAP"Now the job is really getting it out of the rocks, so we've got crews from Seal Rocks in the north right down to the top half of Stockton. We're finding those rocky outcrops is where some of that litter is now depositing, and it's a little bit more inacessible.
"The process now is really waiting for more of this to come ashore, particularly after the high tides."
Mr Mitchell said the clean-up would most likely run into "tens of thousands of dollars a day", but that the cost would be borne by the shipping company's insurers.
"Safety and logistical considerations" prevented the ship from docking sooner, as it had to contain its damaged containers, and battle "atrocious weather" and hazardous surf warnings over the weekend, Mr Mitchell said.
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Authorities expect it could take up to a week to unload the remaining containers from the vessel, with Sydney harbour master Philip Holliday describing the process as a "complicated game of Jenga".
The ship was met in Port Botany by officers from the Australian Transport Safety Bureau and NSW Maritime Safety Authority, which will oversee the removal of the damaged containers and investigate the incident to determine whether further action will be taken against the ship's owners.
The Taiwanese shipping company, Yang Ming, apologised for the hundreds of kilograms of debris that has washed ashore.
"We know that the marine incident has brought a lot of public concern," Yang Ming spokesman Steven Ka said on Tuesday.
"We will take full responsibility to recover and to minimise the impact to the marine environment."
The vessel is expected to continue its voyage to Melbourne, then Brisbane, before returning to Asia.
With AAP
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