Land on the F6 corridor at Gymea, which was previously used for commuter car parking, will remain closed indefinitely.
The site between Gymea Bay Road and Chapman Street was fenced off in June last year after asbestos was found.
A Sutherland Shire Council director told the June council meeting state government officials had advised the site "won't be opened any time soon".
Subsequently, a Transport for NSW spokesman told the Leader work was carried out to make the block "safe for nearby residents and the community".
"This work included fencing the site and placing a suitable layer of clean material on the identified areas," he said.
"Transport for NSW is investigating further remediation work and operational requirements for the site and will update the community when work progresses."
The closure of the site was raised during discussion of a council staff report, which revealed the coronavirus pandemic had created uncertainty over the need for commuter car parking in town centres and transport hubs.
The report advised against the council redeveloping its existing car parks unless in partnership with Transport for NSW or a private developer.
Two council car parks - behind Jannali shopping centre and adjoining Club Cronulla - are already the subject of commercial in confidence negotiations with interested parties.
Woolworths has proposed a shops-residential-parking project at Jannali, while Club Cronulla has been negotiating a redevelopment that would spread across the adjoining, at-grade car park in Croydon Street.
The council report said the coronavirus pandemic had resulted in major disruptions to parking demand and it was unknown if or when demand would return to the pre-existing levels and usage patterns.
"Based on independent feasibility advice, increasing public parking through redevelopment of existing car park sites would require changes to planning controls resulting in development that is of a scale that is likely to be unacceptable," the report said.
"Council's current public parking pricing framework does not support development of viable new commercial parking stations.
"The benefits associated with providing additional free parking at this time are insufficient to justify the significant capital investment required.
"A long term plan for additional commuter parking around transport hubs should be pursued with Transport for New South Wales, being the agency responsible for this service.
"Some of the issues raised in this report regarding management of existing car parking will be covered more fully in the Parking Action Plan scheduled for delivery in 2020/21."