The Metropolitan Redevelopment Authority has contradicted claims by WA's water watchdog that toxins from one of Perth's most polluted sites are leaching into the Swan River.
In a report commissioned by the MRA and prepared by consultancy Greencap, the authority said that a containment cell above Mardalup Park in East Perth was working effectively.
The report flies in the face of research carried out by the Department of Water and its experts on behalf of the Swan River Trust which found the barrier was faulty.
The cell, consisting mainly of clay, was built in the 1990s as part of efforts to remediate the old East Perth gasworks site.
As reported in _The Weekend West _, the trust report found that the barrier had become "compromised" in places since being built. The trust also found the cell never fully covered the site and not enough trees had been planted to keep groundwater levels suppressed.
This meant contaminated groundwater that was laced with toxins, including hydrocarbons and heavy metals, was likely to be leaching into the Swan, the report found.
Although it did not respond to requests to provide a copy of the Greencap report, the MRA, which is responsible for the containment cell, cited the work to insist it was still working as intended.
MRA chief executive Kieran Kinsella said the report also showed no pollution from Mardalup Park had flowed into the Swan.
He said the investigation confirmed the cell was operating effectively and that there was no evidence that contaminated groundwater was leaking into the Swan.