Environmental Site Assessments (ESA’s) – Coffs Harbour, NSW to Maroochydore, QLD

ADG was commissioned by a leading independent fuel supplier to undertake Environmental Site Assessments at 16 operational service stations and fuel depots between Coffs Harbour and  the Sunshine Coast. The objective was to establish current soil and groundwater conditions and to determine the contamination status of each site. The ESA’s were undertaken over a three month period and ADG delivered all reports on time and budget.

Contaminated Site Remediation, Landfill Gas and Leachate Monitoring – South-East QLD

ADG was contracted to undertake a Stage 1 and Stage 2 Detailed Site Investigation of a 50 hectare development site proposed for residential use in South East Queensland. The site had been subject to illegal dumping and landfilling for decades, and was situated adjacent to a closed landfill. ADG developed a Remediation Plan and supervised remedial works which comprised the progressive excavation, screening and removal of waste materials from each stage of development. The Site Validation Report prepared by ADG achieved Third Party Reviewer (TPR) Approval allowing parts of the site to be removed from the Environmental Management Register (EMR) and subsequently developed for residential use.

ADG has established a network of groundwater and landfill gas (LFG) monitoring wells where LFG and leachate impacts have been identified. Ongoing monitoring is currently being undertaken to establish worst-case conditions, and to assist with the preparation of a Conceptual Site Model and Qualitative Risk Assessment Report to assess and address risks to humans and the environment. 

Dewatering Management – Various Sites in Sydney, NSW          

Over the past two years, ADG has developed Dewatering Management Plans for more than ten development projects in the greater Sydney area. The projects typically comprised the construction of residential and commercial towers over double and triple level basement carparks. The Dewatering Management Plans were approved by the Water NSW/Department of Industry (water), Site Auditors and local government to allow temporary construction dewatering and discharge of treated effluent to the stormwater system. Specialist groundwater treatment methods were adopted for each site based on ADG’s recommendations, and regular compliance monitoring was conducted by ADG to identify any potential impacts to the receiving environment. Final Dewatering Compliance Reports were submitted to Water NSW to achieve state government ‘sign off’ once the dewatering systems had been decommissioned.

Contaminated Site Dewatering – Mackay, QLD

ADG obtained approval to dewater an underground storage tank (UST) pit at a service station site in Mackay, Queensland. Groundwater at the site was contaminated with petroleum-based hydrocarbons, and required specialist treatment, including pH buffering, air sparging and activated carbon filtration prior to discharge to the stormwater system. Dewatering compliance monitoring was undertaken by ADG for the duration of dewatering activities, confirming that the water quality objectives were being achieved and that the treated effluent was suitable for discharge into the Pioneer River system.

On-site Wastewater Design for Tourist Development – Mt Tamborine, QLD 

ADG was engaged to prepare an On-site Wastewater Management Report and Site Based Management Plan for a tourist development on a sensitive site in the Gold Coast Hinterland. The development proposal comprised the construction of 20 accommodation cabins and a central lodge with restaurant and day spa facilities. The site was severely constrained by steep, unstable slopes, gullies, groundwater springs and dense stands of rainforest vegetation. ADG overcame these constraints and developed an environmentally acceptable wastewater management strategy for the site, achieving DES approval for an Environmentally Relevant Activity (ERA).    

Acid Sulfate Soil Assessment of the Coomera River Foreshore – Coomera, QLD

ADG was contracted to undertake an Acid Sulfate Soil Investigation to assist with the Morpho-stratigraphic Assessment of the Coomera River Estuary Foreshore. The investigation focused on five parcels of parkland distributed along a 9.8km stretch of the estuary, owned by the Gold Coast City Council. The assessment involved the recovery of discrete soil and sediment samples using a combination of sampling techniques depending on the variable conditions encountered. Field and laboratory analysis was undertaken to determine the acid generating capacity of the soils, and based on this data ADG made recommendations for additional detailed assessment to develop a suitable management strategy for the area.