Seven homes built on the former Newcastle Gasworks site at Waratah are in the process of being demolished as part of a project to clean up a toxic legacy that has dogged the area for almost a century.
A further three properties on the north side of Ellis Road will be demolished in the new year. The land occupied by another two properties will be remediated, but the status of whether the homes require demolition is still being assessed.
The 13 properties were located on or near the footprint of the former gasworks, which closed in 1926.
At least one property had been shifting on its foundations in recent years as a result of an old gas holder swelling and shrinking underneath the house.
The multi-million dollar remediation project will involve the containment or removal of contaminants including cyanide, lead and benzo(a)pyrene from the area.
Property and Development NSW has purchased five of the properties that are presently being demolished as part of a voluntary acquisition process offered to landowners who wished to sell.
The properties will be sold as vacant land on the open market once the rehabilitation program is complete. The process is due to wrap-up in mid-2025.
"Property and Development NSW is working with owners of the remaining impacted sites to provide alternative accommodation for the duration of the remedial program and options for rebuilding of their homes," a spokesman said.
More than 300 soil, vapour and groundwater samples were collected by an independent consultant as part of a 2017 investigation into historic pollution in the area.
In one instance, cyanide, lead, chromium, polycyclic aromatic hydrocarbons (PAH) and benzo(a)pyrene were found above the screening criteria levels in the yard of a Turton Road property.
The former Waratah Municipal Council operated the gasworks from 1889 to 1922 when it sold it to the Newcastle Gas and Coke Company.
Newcastle Gas, which was acquired by AGL, closed the Waratah operation when it opened the larger Clyde Street gasworks site at Hamilton North 1926.
Jemena Gas acquired the Hamilton North property as its associated liabilities from AGL in 2006.
The council and Jemena Gas were in dispute over who should be held responsible for cleaning up the legacy pollution until the State Government agreed to cover the cost.