4 Conclusions and future work
4.1 Progress since previous surveys
The 2006/07 National Landfill Census has shown improvements in landfill design and operation compared to previous years. The total number of operating landfills continues to decrease, with numbers almost halving each time the survey has been undertaken. Cooperation among local authorities has helped the closure of small, substandard landfills, making way for larger landfills more in line with best practice (OECD, 2007). All landfills operating in New Zealand now have consent to do so, and only four sites do not measure or charge for the disposal of waste.
The Census has also highlighted areas needing improvement. The percentage of landfills sited on low-permeability underlying material has stayed the same. One-fifth of landfills collect landfill gas and half of all landfills have an engineered liner in place to prevent leachate. The lack of appropriate landfill sites and engineered liners could result in undesirable environmental impacts. This makes progress in these areas especially important.
However, progress is likely to be limited by many existing consents being valid until after 2020. This means that the greatest opportunity for improvements is likely to occur when existing resource consents for landfills come up for renewal.
4.2 Future work
To ensure further progress is made, the Ministry will:
-
continue to promote and update the existing guidance for landfill siting, design, operation, and closure
-
review the National Landfill Census process as necessary to ensure data collection is effective.
