The NSW Environment Protection Authority (EPA) has completed water testing for more than 85 properties in the Cadia Valley to test for the presence of metals.
Over the past seven weeks, EPA officers have been collecting samples from household kitchen taps and water tanks with all samples were sent to the NSW Government's Environmental Forensic Laboratory for analysis.
Results from the first 40 properties sampled have been received and compared to the Australian Drinking Water Guidelines. The majority of results from kitchen tap samples showed metal concentrations below the guideline values. At two properties, lead was detected at or marginally above the accepted level of lead at the kitchen tap, but water tank samples from the same properties were below guideline values.
Water tank samples showed six properties had levels of lead above the guideline's values, while kitchen tap samples at these properties were below guideline values.
Individual test results have been provided to property owners and they will be offered an opportunity to discuss the findings with the EPA.
NSW Health recommends that bore water (groundwater) is not used for drinking, cooking and personal hygiene including cleaning teeth and bathing) without testing and appropriate treatment including disinfection.
Once all tests from the water sampling program are completed, broader comparisons will be made with water sampling results previously undertaken by NSW Health, surrounding industry and the community. Both the EPA's and NSW Health's Expert Panels will also consider the results.
Where possible, officers have collected sludge samples from water tanks and these will be reported separately.
The results of the testing also show how important it is to maintain tanks and tank water distribution systems to ensure a safe supply of drinking water.
First flush devices at the tank inlet can help to reduce the amount of dust, bird droppings and leaves being washed into tanks. It is also good practice to flush rainwater taps used for drinking or cooking for two to three minutes at the start of each day as water that has been standing for a long time can dissolve metals such as copper and lead from pipework. This "first-flush" of water is safe to use for non-drinking uses.
Tanks should be examined for accumulation of sludge at least every two to three years and, if sludge is present, it should be removed by siphon or by complete emptying of the tank (desludging).
The EPA has also begun an extensive air monitoring program in the Cadia Valley. A total of 30 smart sensors – or Purple Air Monitors – have been distributed to residents across the Valley.
A summary of all water sample results is available on the EPA website. Expressions of interest for water sampling will close on Friday 4 August.
