Vent stacks to be removed from Ngaruawahia Closed Landfill

09 December 2015

Contractors will be removing the vent stacks from the Ngaruawahia Closed Landfill from the week beginning 14 December, providing the weather is favourable for the work to go ahead.

Waikato District Council’s Service Delivery Manager Tim Harty said the 10 vent stacks, which look like chimneys, are no longer serving a purpose for the landfill.

Landfill gas production is expected to have peaked more than 25 years ago during active landfilling and is now expected to be very low and continuing to decline.

Mr Harty said Council recently applied to the Waikato Regional Council for resource consent to allow for ongoing discharge of a limited amount of gas in to the soil.

“We commissioned a report for the consent to look in to whether there were any environmental effects from the leachate. During this process it was discovered the vent stacks have served their purpose and therefore, we will be removing them,” he said.

Land fill gas emissions are not at a level that is of risk to people living in the vicinity, providing occupants follow recommendations for development and notify any changes in land use.

The report shows that leachate does not appear to be having any adverse environmental effects. 

Mr Harty said landfill gas has not been found in nearby houses but has been found below the ground in a specific area which has implications for selected properties and roadside services. Landowners and dwellers have been advised and monitoring will be ongoing.

“There will need to be limitations on some activities such as open fires and hangis on some properties. Those affected landowners have been advised,” Mr Harty said.

Residents can continue to cultivate vegetable gardens as consuming produce from the garden in the affected area carries no health risk.

Mr Harty said Fulton Hogan is being contracted to remove the vent stacks and the process will take a few weeks, depending on the weather.

Closed landfills are most commonly used as reserves or parks and removing the vent stacks could allow for the Ngaruawahia Closed Landfill to be used for this purpose in the future.

For further information

Ginny Semmens
Communications Advisor
Waikato District Council
07 824 8633 Extn: 5778
ginny.semmens@waidc.govt.nz