Spicer Landfill Updates

Background

Porirua City Council provides information about the odour problem at Spicer Landfill as part of its commitment to improve communication with the community.

Most complaints about odour attributed to the Spicer Landfill are from residents in the western hills of Tawa, although some complaints also come from residents within the Linden area and from eastern hill suburbs.

Wellington City, Porirua City, and Greater Wellington Regional Councils, with Tawa Community Board members, have agreed to work together to deal with the odour problems from the Spicer Landfill.

Wellington and Porirua City Councils are partners in a joint venture that owns the landfill, with Porirua in charge of the tip operation and Greater Wellington Regional Council having a regulatory role.

At a subsequent meeting it was agreed that information would be shared with the public and today the Council is releasing three reports about Spicer Landfill.

A number of reports and documents are available:

The reports to the joint committee include steps to address recommendations made in the independent review by Beca in December 2015 and the GWRC compliance monitoring report.

These actions are summarised below:

  • Wellington Water Limited (WWL) has changed the operation at the treatment plant so that sludge is not held in bins overnight, and processing of sludge removal is starting earlier.
  • Protocols have been established for communications between the two Council operations. Landfill and treatment plant managers meet at least monthly.
  • A 12 month forecast for cleanfill requirements has been developed.
  • A significant stockpile of cleanfill (around 20,000 tonnes) has been built up over January and February.
  • In recent months the volume of sludge has reduced and the waste to sludge ratio is currently similar to 2011 levels.
  • A three month trial is underway using a mobile deodorant spray unit.
  • A desktop evaluation of fixed boundary spray options is underway.
  • A draft Landfill Gas Management Plan has been prepared and is being reviewed by GWRC.
  • Additional gas wells and laterals have been installed.
  • Interested Tawa residents are advised via email of landfill works that may generate odour.
  • Ongoing work aimed at minimising size of exposed waste in filling cell.
  • Significant quantities of additional intermediate cover have been applied to areas outside the active filling area to stop small leaks.
  • A consultant has been commissioned to review the possible benefit of a boundary odorous gas detection system.

 



 

Spicer Landfill Q&As

Spicer Landfill has been in operation since 1976. Over the last two-three years there have been increasing complaints about bad odours coming from the landfill.

Who owns and manages the landfill?
Spicer Landfill is a joint venture, owned by Porirua City Council (78.5 per cent) and Wellington City Council (21.5 per cent). The landfill is managed by Porirua City Council.

Who governs the landfill?
Porirua City Council (PCC) reports to a Joint Venture Committee which has representatives from both Porirua and Wellington City Councils (WCC).

Who operates the landfill?
EnviroWaste Services Ltd operates the landfill on behalf of the two Councils.

What is Greater Wellington Regional Council’s role?
Greater Wellington Regional Council (GWRC) plays a regulatory role. They ensure the landfill is operating according to its resource consent conditions. The GWRC also responds to complaints from the public.

What is causing the odour?
The odour is caused by the gas in the landfill which is created by waste as it breaks down.

Does the sludge (or bio-solids) going to the landfill meet resource consent conditions?
The bio-solids accepted at Spicer comply with both the landfill resource consent and the landfill Waste Acceptance Criteria.

Who operates the wastewater treatment plant?
Wellington Water Ltd is contracted to run the wastewater treatment plant. Porirua City Council manages the contract.

How can you make the gas less odorous?
We have increased the number of gas capture wells to 22. These direct the gas to a flare where it is burned and in doing so removes any odour associated with the gas. More wells will be installed as required.

What else is being done about the odour?

We have:

  • Reduced the amount of liquid in the sludge 
  • Reduced the open tipping area
  • Increased the depth of clay cover over the filling areas
  • Added extra cover at the end of each day
  • Planted more trees on the Tawa boundary
  • Continue to monitor daily and respond
  • PCC, WCC, Envirowaste Services Ltd, GWRC and WWL are working more closely.
  • A report is being commissioned to offer solutions for the medium to long term as well as alleviate short term odour problems. 

Is there any public health risk from gas produced by the tip?

  • The odour that residents smell is unpleasant but not dangerous.
  • All landfills produce odorous gasses but only some operators capture those gases and destroy them. The Councils took a proactive approach at Spicer and started capturing and burning the gas in 2009. Extra gas wells have been installed at the landfill as required. At Spicer we have 22 wells that capture gases which are then destroyed by a flare.
  • The flare performance is monitored continuously and the gas system is inspected weekly.
  • A monthly survey of gas concentrations at the landfill surface is carried out because gas can sometimes migrate to the surface at different locations.  Where small leaks are found, they are sealed with more clay.
  • The gas system has been professionally designed and constructed by specialists in this area. It is being continuously reviewed and improved as the landfill expands.  This includes reviewing the performance of gas wells (which changes over time requiring modifications), and the installation of new wells as required. Some of the gas wells capture gas from the old landfill under the existing one. 
  • Landfill staff who may be exposed to landfill gas, for example when working on the gas system or digging into the landfill, wear personal gas sensors. This is also the case at the other landfills operated by the contractor.

How do I make a complaint about odour?
Phone Greater Wellington Regional Council on 0800 496 734 and they will log your call and investigate.