Landfill Gas Mitigation Study, Remediation Plan

Client:                      Confidential
Location:                Auckland
Project Value:       Undisclosed
Sector:                    Environmental
Completion:          Current


GWE was engaged to undertake a multi-disciplinary site investigation covering site contamination, geotechnical and landfill gas.

Elevated concentrations of metals and asbestos were recorded in shallow soil materials across the site which required significant cut to waste.  GWE delineated soil contaminant conditions to ensure cost-effective waste disposal was provided. 

Based on findings of the landfill gas risk assessment, ground gas mitigation measures were developed which covered foundation design, passive ventilation, and a membrane.

The project design required the directional drilling of services from the site through the neighbouring closed landfill.  GWE 

completed additional geotechnical investigation and contaminated land sampling to ensure this proposal was technically feasible. 

As part of the resource consent process GWE worked closely at the interface between the applicant, and the regulator to ensure pragmatic resource consent conditions were adopted. 

GWE was retained to provide construction monitoring and validation of remediation works.


  • Contaminated land investigation and reporting.
  • Landfill gas investigation and risk assessment.
  • Geotechnical investigation and reporting.
  • Waste classification services.
  • Contaminated land regulatory evaluation and liaison services.
  • Development of remedial options and ground gas mitigation options.
  • Remedial action plan development.
  • Construction observation and compliance including validation sampling and reporting.