Landfill Gas Assessment — Bus Depot, Albion VIC

Project overview

A council planning condition required a landfill gas (LFG) risk check prior to redevelopment works at an operating bus depot in Albion, Victoria, located near two closed municipal landfills. iEnvi delivered a lean, risk-based assessment designed to close the data gap quickly and safely so construction could proceed on schedule.

Field program and methods

• Reused two existing onsite groundwater monitoring wells.
• Probed three shallow hand-auger locations within grassed margins.
• Screened accessible stormwater pits and drains and completed an ambient surface walkover.
• Direct landfill gas monitoring at 10 locations using a calibrated GA5000 field instrument.
• Concurrent groundwater sampling to provide multiple lines of evidence.

Findings

• No methane was detected at any of the 10 monitoring points; carbon dioxide and oxygen readings were within normal background ranges.
• All field LFG results were below the EPA Victoria action levels used for interpretation.
• Groundwater results showed very low ammonia and related indicators consistent with a weak, residual leachate signature typical of mature, stabilised closed landfills.

Risk interpretation and outcome

Combining direct gas measurements with supporting groundwater chemistry provides a robust, conservative assessment. The data indicate a negligible potential for significant landfill gas generation at the site and a low, acceptable risk to the proposed redevelopment and ongoing industrial use. Based on these results, no additional LFG monitoring or mitigation was recommended and the council planning condition was satisfied, keeping the project on schedule.

Practical takeaways for developers and asset owners

• Targeted, risk-based investigations that align with scheduled monitoring can close planning data gaps quickly and cost-effectively.
• Using multiple lines of evidence (direct gas monitoring plus groundwater chemistry) reduces uncertainty and supports defensible risk decisions.
• Single mobilisation field programs minimise site disruption and hold costs while meeting compliance requirements.

To discuss targeted contaminated land, landfill gas or groundwater assessments for your project, call iEnvi on 13000 43684 or visit our contact page.