A bright green substance dumped in a drain at Unanderra prompted a full-scale emergency, but experts say it wasn't toxic.
Emergency services initially raced to Musgrave Place in Figtree just after 11am on Thursday, October 19, after a creek running near homes and a childcare centre turned bright green.
Five fire trucks, specialist HAZMAT crews, council staff and the Environment Protection Agency (EPA) were called in to the 'Kermit the frog' coloured waterway, which runs off American Creek.
A drone was put into the air to gauge how big the potential environmental disaster was as crews gathered by the water to begin testing.
The green substance was traced upstream through the drainage system to a drain in a soccer field off Richards Street in Unanderra.
There, HAZMAT crews discovered a heavy concrete cover over the drain had been left ajar by the person who dumped the green liquid.
"Our devices haven't been able to determine the actual substance itself, but the main thing is it isn't toxic," Fire and Rescue NSW Inspector Greg Purvis said.
Testing did show the liquid was not fluorescein (known as plumber's dye) that's often used to locate leaks or trace underground pipe networks.
The Mercury understands the liquid will be left where it is and it will naturally disperse through the creek systems.
Click on the picture below to see more photos from the emergency response.
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