THE Department of Environment wants Wesfarmers CSBP to take urgent action to stop further groundwater contamination from the polluted site of its former fertiliser plant in Bayswater.
A consultant’s report has detected contaminated groundwater up to 400m from the former Cresco plant in Railway Parade.
The report, submitted to the department on May 15, found metals, phosphorus, ammonia, fluoride, sulfate and acidic conditions in groundwater within a 250m-wide zone south-west of the contaminated facility.
The investigation into the extent of the groundwater plume found the contaminants were not reaching the Swan River.
But some Bayswater residents and businesses are being warned not to use bore water due to possible contamination, with a Health Department assessment of monitored sites due next week.
CSBP has submitted a remediation proposal, but the department is concerned about the time it will take and wants prompt action to prevent off-site migration of contamination.
There is no power to enforce the department’s request, a problem being addressed by legislation before Parliament which will bolster powers to investigate contaminated sites and issue clean-up notices in suspected cases.
But the department has suggested measures such as the installation of a reactive barrier wall or pump-and-treat system could prevent ongoing contamination.
Department land and water quality manager Sharon Clark said the contaminants found in the groundwater were of significant concern and continued pollution was unacceptable.
Ms Clark said the report found that concentrations in drain and river sediment did not exceed national quality guidelines.
The Swan River Trust, the Department of Fisheries and the Department of Environment would this month provide independent assessments of the impacts within the drain and the river at the end of June.
The clean-up of contaminated groundwater from waste dumping at the former Cresco plant has been a point of contention between CSBP and environmental authorities for several years.
CSBP sold the site in 1987 under an agreement that managing director John Gillam has previously claimed transferred responsibility for remediation to the purchaser, developer Northcorp Pty Ltd.
CSBP was not available for comment yesterday.