East Perth gasworks site $15M clean-up completed

18/3/96

The State Government has completed a $15 million clean up of the old East Perth gasworks site.

Planning Minister Richard Lewis said the remediation and rehabilitation of the eight-hectare site was one of the most significant environmental projects ever undertaken in Western Australia.

"In total, more than 200,000 cubic metres of soil has been excavated and assessed for treatment and disposal to allow the redevelopment of the site into parkland and an adjoining residential estate," Mr Lewis said.

"The clean-up of the old gasworks is an essential component of the East Perth redevelopment program and will greatly contribute to the overall ecological improvement of the Swan River."

The Minister said the site had been successfully converted from a contaminated industrial area to a valuable public asset within the East Perth redevelopment area.

"The East Perth project is a major commitment towards planning Perth's future. Its legacy will provide a major benefit for future generations of Western Australians," he said.

Decommissioned in 1971, the old East Perth gasworks produced gas for nearly 50 years. However, the surrounding environment was contaminated after chemical by-products, including coal tars, leached on to the site. Surface and groundwater carried the by-products into the Claisebrook Drain and the Swan River.

Mr Lewis said the contamination was first identified in the 1980s.

"Extensive testing revealed the existence of several chemicals at levels which could have posed a health risk and endangered the eco-system of the Swan River in the longer term," he said.

Rather than localise and contain the contaminated area, the East Perth Redevelopment Authority, with the financial assistance of Alinta Gas, commenced a remedial operation for the entire site.

About 30,000 cubic metres of river sediments, to a depth of one metre below the surface of the river bed, were removed by dredging, then pumped to a series of ponds to be treated.

Excavated areas of the river bed were then backfilled to the original surface level with clean sand.

Mr Lewis said the final component of the clean-up operation involved remediating 8,000 cubic metres of contaminated material within the site through bioremediation.

"This process involved the cultivation of naturally occurring bacteria found in the soil which then consumed the tars, converting it to simple compounds such as carbon dioxide and water," he said.

"The treatment, which is now complete and has allowed the material to be disposed as landfill, is a first for Australia on this scale."

The Minister said each aspect of the project was controlled by a Quality Assurance Plan which included control and monitoring procedures for gases, vapours, ground water, dust, river water impacts, worker safety and material transport.

"The foreshore river flats will be transformed into a three-hectare parkland comprising river side pedestrian paths, natural bush gardens, artwork features and a playground," he said.

"It is anticipated that 60-70 residential units will be built on the gasworks site over the next three years and significant areas of public open space will complement the development."

Mr Lewis said the project was the first large-scale remediation and rehabilitation of a gasworks site in Australia and a milestone in the redevelopment of East Perth.

"It has enabled the rejuvenation of a severely blighted area and improved access to one of the city's greatest assets, the Swan River," he said.

The Gasworks Park will be officially opened in July.

Media contact : Bronwyn Hillman 222 9595, 221 1377