Yarramine was engaged by Toowoomba Regional Council to undertake a contaminated land investigation of a former dip site at Cabarlah, north of Toowoomba.  The site was previously used for tick treatment of horses and cattle with a plunge dip between 1915 and 1984.

The objective of the contaminated land investigation was to remove the site from Department of Environment and Science’s (DES) Environmental Management Register (EMR) prior to its divestment by Toowoomba Regional Council.

The site was listed on the EMR for Notifiable Activity 22: Livestock dip or spray race operations (operating a livestock dip or spray race facility), and as a result of investigation activities, resulted in this listing also being for the Hazardous Contaminant of arsenic with a maximum concentration of 2,850 mg/kg discovered prior to remediation.

The original scope of the investigation expanded as information and results came to hand during its course and ultimately included assessment of soil contamination through what ended up becoming five (5) separate sampling and testing rounds, notification to DES of a hazardous contaminant and preparation of a Tier 2 Risk Assessment using SBET analysis, an uncommon but not unheard of method to derive site-specific investigations levels for arsenic.

Along with the above sampling and testing rounds, fieldwork also involved decommissioning of surviving site infrastructure and site remediation undertaken also expanded as information and results came to hand, involving offsite disposal of arsenic impacts soils.