Landfill Gas Risk Assessment for a Proposed Commercial Development Adjacent to an Operational Landfill
Location – Victoria
Project Value – $20k+
Project Summary –
AEA was engaged to complete a landfill gas risk assessment (LFGRA) for a proposed commercial development located adjacent an operational landfill. The LFGRA was undertaken in compliance with a condition placed by the local council.
No previous investigations or risk assessments had been completed for the site. However, the LFGRA was undertaken in accordance with best practice published guidance, utilising the significant data available of the adjacent landfill to quantify whether LFG is present, and whether LFG poses a risk to land users of the site.
The LFGRA considered the gas monitoring data from the adjacent landfill, the changing configuration of the landfill due to its operation, as well as the conceptual site model of the landfill and the subject site. The LFGRA did not consider impacts on the amenity of the subject site from landfill operations.
Outcome & Highlights –
AEA identified a risk range due to uncertainties around the cause of highly variable gas flow rates within the sub-surface geology and proposed changes in configuration of the adjacent landfill.
AEA recommended an in-ground pathway intervention structure (pathway break) be considered as an option for protecting the subject site from LFG sub-surface migration now and in the future, as gas protection measures integrated into building design are not appropriate due to the inability to determine future LFG sub-surface migration risks to the users of buildings and structures at the subject site.
- The LFGRA identified that LFG potentially could pose a risk to adjacent land users and provided mitigation measures to minimise these risks by recommending engineering controls.
- The AEA LFG expert team assisted the client with completing, and was successful in providing, an LFGRA to the auditor for review to enable residential development to progress.