Human Health & Ecological Risk Assessment

Greencap offers specialist services in Human Health Risk Assessment (HHRA) and Ecological Risk Assessment (ERA). These services provide cost-efficient remedies to manage potential environmental risks and allow resources to be targeted to those sites or activities that pose the highest risk. Risks can be due to human activities such as current or historical industrial operations, mining or waste management practices, or may be related to naturally-occurring substances.

Human Health Risk Assessment considers the potential risks to human health from exposure to chemicals and hazardous materials such as heavy metals, hydrocarbons, solvents and asbestos in the environment (e.g. air, soil, groundwater and/or surface water). The risks can be assessed for residents on a contaminated site, children in a school or playground, workers in an occupational setting, or other community groups. 

Ecological Risk Assessment considers ecosystem risks if they are relevant to the type of environment and land use or proposed development.


The Tiered Approach to Risk Assessment

Greencap uses a tiered approach to HHRA and ERA, in line with the National Environmental Protection Measure (NEPM) guidance. 

A screening level assessment is the first stage (Tier 1), where known site data is compared to published health or ecological risk-based guidance levels, such as the Health Investigation Levels or Ecological Investigation Levels.

If known site data exceeds the risk-based guidance levels, a Tier 2 HHRA or ERA can be undertaken, using conservative assumptions about the site, the receptors and the expected exposures. If a Tier 2 Risk Assessment estimates there is low risk to health or the local ecology from the contaminants, then there is no need to continue to the next tier.

Most sites only require a Tier 1 or Tier 2 assessment.



The two primary outcomes of a HHRA or ERA are:

  • Advice about the level of potential health risk on the site and whether the site is suitable for the use
  • Development of site-specific clean-up criteria, or Site-Specific Target Levels (SSTLs) or Trigger Levels that can be included in an Environmental Monitoring Plan

A risk assessment report can provide information to support a site owner, auditor or regulator to decide on a site’s suitability for use or development, even if some contamination is present. Risk assessments can also help minimise the amount of clean-up or controls needed to manage potential risks and reduce the time and costs for regulatory compliance.


Australian Guidance Documents

Greencap risk assessment services are guided by the primary national guidelines for risk assessment including:  


Contact Our Experts

Brent Ridgard

National Practice Lead - Environment

Nick Waniarcha

National Operations Manager - Environmental Management

Darren Cordy

Manager - Contaminated Land

Dylan Burford

Manager – Environmental Management & Contaminated Land