Bioremediation is a process that promotes the natural microbes in soil to digest hydrocarbon-based contaminants, such as polycyclic aromatic hydrocarbons (PAHs) and petroleum hydrocarbons (TPHs). These contaminants are commonly found in waste by-products from gas ...
The bioremediation process at the Soil Recycling Facility of EESI’s long–standing remediation partner New Soil involves stockpiling the impacted material on the bio-pad in the treatment area and mixing it with additives such as surfactant (EESI18), green mulch, manure, and a nitrogen source. The stockpiles are cultivated via turning with an excavator on a regular basis to allow air into the stockpiles, and soil testing is undertaken regularly to measure the progress of the treated material and analysed for contaminants of concern.
The process is repeated until validation samples show that the soil has been successfully decontaminated to an acceptable level for reuse off-site or on-site. Independent consultants collect validation samples, which are analysed at NATA approved laboratories. The stockpiles must remain aerobic through turning with an excavator to allow the conversion of hydrocarbon compounds to carbon dioxide, water, and microbial cell mass.
The treated and validated soil can be reused in three potential ways: it can be returned to the site where the contaminated soil has been sourced from to back-fill excavations, it can be remediated to NSW guidelines for re-use at landfill as day cover, or it can be re-used on site.
All soil material brought to the Soil Recycling Facility to be treated and recycled meets the requirements of the NSW EPA Environment Protection Licence (EPL number 13413) for the SRF. The process may vary slightly depending on specific contaminants and matrix materials in each batch of hydrocarbon-contaminated material received, but the technology is based on soil science principles and involves continually assessing the properties of input material and the material undergoing treatment to ensure the maximum bioremediation rate is achieved.
The Environmental Earth Sciences International Group acknowledges the Traditional Custodians of country throughout Australia and their connections to land, sea and community. We pay our respect to their Elders past, present and emerging and extend that respect to all Aboriginal and Torres Strait Islander peoples today.
