Contaminated Sites

At HRS we are committed to providing our clients with cost-effective contaminated site assessments and remediation works. Our works include:

  • Preliminary Site Investigations (PSI)
  • Monitored Natural Attenuation (MNA) Programs
  • Detailed Site Investigations (DSI)
  • Site Management Plans
  • Site Remediation Plans
  • Regular Monitoring
  • Soil Remediation
  • Underground Storage Tanks
  • Groundwater Treatment Programs
  • Environmental Due-Diligence Assessments


Preliminary Site Investigations (PSI)

A Preliminary Site Investigation (PSI) is predominantly a desktop study that determines the potential pollutant risk at your property based on past and present land uses of your property and those nearby. The Preliminary Site Investigation includes a desktop study, a detailed site inspection and interviews with site representatives. If the Preliminary Site Investigation concludes that the property may be contaminated it will generally be recommended that a Detailed Site Investigation be performed.

Detailed Site Investigations (DSI)

During a Detailed Site Investigation (DSI) comprehensive data will be collected and soil and/or groundwater samples will be taken for laboratory analysis to confirm the nature and status of the pollutant of potential concern identified in the Preliminary Site Investigation.

Site Remediation Plans

A Site Remediation Plan documents the strategy used to contain or remove the contaminant source and remove pollutants from the environment.  This strategy must be effective at removing all components of the contamination, be in accordance with current DER guidelines, be acceptable to the client and neighbouring properties (if applicable), be cost-effective and be environmentally sustainable.

Soil Remediation

Contaminated soils can be treated in a number of ways depending on the type of contaminant(s) present, the depth and concentrations of the contaminate, the type of soil, the depth to groundwater, the proximity of sensitive environmental or human receptors, and more. Soils can be treated in-situ, excavated and treated on-site, excavated and treated off-site or excavated and sent to appropriate landfill.

HRS has extensive experience in treating contaminated soils and can select the best method for your project.

Groundwater Treatment Programs

Groundwater is water stored within porous rocks below the earth’s surface. Groundwater can be polluted when contaminants contained within soils slowly leach through the soils until they reach groundwater. At HRS we developed our own highly effective groundwater treatment system. Recent site remediation works have seen pollutant memorials removed from client sites and property values restored.

Monitored Natural Attenuation Programs

Monitored Natural Attenuation programs may be implemented where the risk to human and environmental health is considered low and contaminates are of the type that degrade through natural processes. Monitored Natural Attenuation programs requires the environmental consultant to perform regular monitoring of sites to confirm that contaminates are degrading at a rate considered acceptable to the DER in Western Australia.

Site Management Plans

Site Management Plans are generally developed to ensure a site that has been remediated stays clear of pollutants.  Management activities include changes to work processes or practices at the site, covering areas at risk with hard surfaces such as bitumen to prevent contaminants leaching through the soils and ongoing monitoring.

Regular Monitoring

Regular monitoring can be conducted for many reasons. Monitoring of groundwater about underground storage tanks helps early detection of possible leaks or undetected spills that may be occurring during refilling. Regular monitoring of leased sites can determine when pollution was first detected and therefore who may be liable for the pollution at the site. The earlier pollution is discovered and responded to, the better the chance the remediation program will be fast, effective and budget-friendly.

Underground Storage Tanks

Underground Storage Tanks are considered an environmental risk as being located underground any uncontrolled release of substances stored within the tank may be difficult to detect or identify. HRS can help in removing any underground storage tanks that are located on a property that are no longer used or required. HRS performs regular groundwater monitoring programs for a number of sites around Perth with underground storage tanks.

Environmental Due-Diligence Assessments

These assessments can be performed prior to purchasing or leasing a property. Similar to a PSI, these assessments inform you of the potential risk from historical contamination at a property you may be looking to purchase. If you own or are purchasing a commercial property to lease these reports could save you thousands of dollars, if in the long run pollution is detected and pollutant liability is being established.