Up until the 1960s the site operated as an informal landfill where all sorts of materials, including hazardous waste, were dumped. The contaminated material needs to be removed to ensure the long-term safety of the water supply network.
“Testing of the soil that we did as part of our wellhead improvement programme has confirmed the presence of heavy metals and polycyclic aromatic hydrocarbons (PAH), associated with old gas works waste, and asbestos,’’ says Council Acting Head of Three Waters Brent Smith.
“These contaminants don’t pose any immediate risk to our water supply but PAH’s can, in the long-term, degrade the polyethylene pipes that are used in the water supply network.
“We take our artesian drinking water from a long way below where the current material is, so it’s important to note that there are no current risks of these contaminants reaching the water supply,’’ Mr Smith says.
“However, we need to permanently remove the soil to ensure the safety of the water supply and its compliance with the Drinking Water Standards for New Zealand.’’
The workers removing the soil will be wearing full personal protective equipment, including masks, for health and safety reasons. During the works, contractors will use dust management protocols such as wetting down the exposed soil and covering stockpiles to prevent dust generation. Air quality monitors will also be used to monitor air particles as an additional precautionary measure.
“We want to reassure residents living near the site that we’ll be using all safety measures to keep everyone safe. They should not be alarmed to see workers on the site wearing full personal protective equipment. That is standard health and safety practice for this type of work,’’ Mr Smith says.
The contaminated material from the site will be safely disposed of at Kate Valley Landfill. Work will take approximately four months to complete.