Residents living near Orica's former chemical plant at Port Botany in southern Sydney say an independent review of mercury contamination around the site does not go far enough.
The Environment Protection Authority (EPA) says it will assess current data to decide if mercury testing in the surrounding residential area is required.
The review will be conducted in consultation with New South Wales Health and paid for by Orica.
But resident Chantal Snell, who lives just one kilometre from the plant, says testing should be done right now because mercury cell technology was used extensively at the site.
She says if there is contamination it is important that it is treated as soon as possible.
"There's a history of an awful lot of chemicals onsite from Orica and around the area and we need to understand whether they have travelled, given they've been onsite for such a long time," she said.
Ms Snell says the EPA review alone will not give locals the peace of mind they are after.
"Residents want to see testing undertaken in their community.
I think residents want that reassurance that there is no risk to their health and a review of data may be a good first step but testing is required and required urgently," she said.
This week EPA acting chief executive Mark Gifford said there had been some testing done outside Orica's plant, and mercury was detected in a nearby canal which was cleaned-up.
"I particularly, very clearly understand the community's concerns around what is the legacy, the historical activities on that site and in that area," he said.