No health risks have been found for residents living near a former BlueScope Steel site in Unanderra where elevated levels of a potentially toxic chemical were discovered last month.
Elevated groundwater readings of the carcinogen trichloroethylene, known as TCE and commonly used as an industrial cleaning solvent, were found at the former BlueScope Stainless Steel site off Marley Place in March.
Increased levels of TCE were found about two to three metres below surface level at a localised section of the north-western end of the site when the company began a new groundwater sampling program.
Precautionary testing began on nearby streets a month ago.
BlueScope's manufacturing boss John Nowlan said all test results were within safe limits.
He said there was not considered to be any health risks for residents.
One test at the rear of a property returned a "very low level" concentration of TCE in groundwater and soil, but the results were within the acceptable criteria.
The NSW Environmental Protection Authority confirmed the level of TCE was not considered significant.
Mr Nowlan said about 100 samples from around 10 properties near the site were tested for TCE.
He said independent experts had confirmed the site was safe for employees working there and for RailCorp employees working in the rail corridor next to the site.
The source of the contamination has been identified and remediation work has started.