1. This technology is untested in Hills geology.

2. Privately owned: if the private owner goes broke, or the WWTP is impacted by bushfire or frequent and prolonged, and common power outages in the area, backups and overflows will occur  causing potential contamination of the nearby pristine waterways, and potential health impacts on residents.

3. The plan cites dam water connected to the operation of the WWTP as an available source for bushfire fighting. Hills’ Local Volunteer Bushfire Brigade members say using dam water as a backup in a bushfire emergency is THE LAST RESORT - and most often totally disregarded because dam water can contain rocks and other debris that clog fire-truck pumps and pipes and the content of the water is unknown (causing contamination of the firetruck / pipes,  and potentially contamination of private property the water might be used on - even people).

4. The Mundaring plant, which uses the same technology, is inadequate, has frequent breakdowns and failures, complaints of smell, noise, and is a mosquito breeding site, as cited by Mundaring residents in Craigie Street.

5. Potential for pollution, contamination of pristine ground water, sits next to Suzannah Brook Catchment, Water Corp WA refuses to involve itself in the plant because of high financial risk to taxpayers.

6. Risks of leaching or contaminating ground-water aquifers or dams relied on by many local residents as their only water source. This is particularly important for the Suzannah and Jane Brooks which have significant Aboriginal heritage value. Holding dams historically rupture and leak and can contaminate pristine aquifers on this site.

7. Ongoing operational and maintenance costs risk being passed onto Mundaring shire ratepayers with no benefit to anyone outside of this private housing estate - or, ultimately State taxpayers if it’s passed to Water Corp to operate.