The NSW Environment Protection Authority (EPA) has released two draft Contaminated Land Guidelines.
The draft guidelines include:
- Contaminated Land Guidelines: Consultants reporting on contaminated land (Consultants Guidelines); and
- Contaminated Land Guidelines: Assessment and Management of Hazardous Ground Gases (HGG Guidelines).
Public consultation on each draft guideline closes on 8 October 2019.
We have set out some of the proposed changes under each guideline below.
Draft Consultants Guidelines
The Consultants Guidelines describe the stages of reporting on the management of contaminated land and provide checklists of reporting requirements. They provide a reporting framework to ensure that reports contain correct information in a suitable format to allow for efficient review by regulators, site auditors and other interested parties.
Key changes to the Consultants Guidelines include:
- New stages: the draft guidelines introduce the following two new stages in the reporting process, being to develop a sampling and analysis quality plan and to consider site specific risk assessments and modelling.
- Sampling and analysis quality plan: this new stage must document the planning process for collecting and evaluating data during the subject site investigation. They should vary in detail according to the scope and level of information available to the consultant and must be flexible to account for changes arising during site investigations.
- Site specific risk assessments and modelling: If undertaking site-specific risk assessment such as Human Health Risk Assessments and Ecological Risk Assessments, a tiered approach is usually followed and may require modelling to predict environmental concentrations. When undertaking modelling, consultants should clearly describe assumptions and uncertainties.
- New requirements for existing stages: the draft guidelines provide further detail on existing stages such as long-term site management and monitoring. Monitoring reports must include a background to the site (including a conceptual site model), justification for any departures from the required monitoring plan and consideration of site-specific criteria which may trigger additional remediation work, among other things.
- Duty to report: following a preliminary site investigation or detailed site investigation, consultants should take reasonable steps to draw their client’s attention to any potential duty to report contamination requirements under section 60 of the Contaminated Land Management Act 1997 (NSW).
- Remedial action plans (RAPs): guidance on what is to be included in a RAP has been expanded and clarified. RAPs must now:
- summarise findings of preliminary and detailed site investigations;
- document identified contamination risks to human health and/or the environment;
- set remediation objectives to ensure a site will be suitable for its current or intended purpose;
- define the extent of remediation required and assess options to achieve the remediation goals;
- document in detail all procedures to reduce risks posted by contamination;
- establish environmental safeguards required to complete remediation in an environmentally acceptable manner;
- identify necessary approvals and licences;
- outline waste classification, handling and tracking requirements;
- ensure remediation is consistent with relevant laws, policies and guidelines;
- identify how successful implementation of a RAP will be demonstrated; and
- identify the need for and nature of any long term management.
- Long-term site management: the draft guidelines state that where full clean-up is not feasible, or on-site containment of contamination is proposed, an environmental management plan (EMP) may be required. An EMP must address the mixing of environmental mitigation and monitoring measures for soil, groundwater and/or hazardous ground gases throughout an existing or proposed use. An EMP must also state its objectives and describe the nature and location of contamination at a site and what long-term site management is needed to ensure ongoing protection of human and environmental health.
The Consultants Guidelines will replace the existing Guidelines for Consultants Reporting on Contaminated Sites (2011).
In addition to the EPA and EPA guidelines, the appropriate planning authority should always be consulted where contaminated land is subject to the NSW planning framework (eg. rezoning or development applications). The relevancy of any planning instruments or guidelines must also be considered, including:
- State Environmental Planning Policy No 55 – Remediation of Land (SEPP 55); and
- Managing Land Contamination Planning Guidelines SEPP 55 – Remediation of Land (Department of Urban Affairs and Planning and EPA 1998).
Draft HGG Guidelines
The HGG Guidelines outline the origins and migration of hazardous ground gases (HGG), describe measures for assessing risk and management options and consider the statutory and regulatory scheme for monitoring HGG. The HGG Guidelines are intended to provide comprehensive guidance for assessing and managing ground gases on contaminated land in New South Wales. The draft HGG Guidelines are intended to incorporate updates in other guidance documents such as the National Environment Protection (Assessment of Site Contamination) Measure 1999 (NEPM) and the British Standard 8576:2013, Guidance on investigations for Ground Gas – Permanent Gases and Volatile Organic Compounds.
Key changes to the HGG Guidelines include:
- Consolidation of HGG management guidance: the draft guidelines incorporate updates from other guidance documents such as the NEPM (May 2013 revision), mining and work, health and safety legislation and industry standards on managing HGG.
- New detail on uncontrolled fill and landfills: the draft guidelines provide greater detail on uncontrolled fill as a source of HGG and the management of HGG associated with development on closed landfills. The draft guidelines identify notable risks of which consultants should be aware. For instance, in the Hunter and Illawarra regions of New South Wales, ‘Chitter’ (coal washery reject) has been widely used as fill-material. Chitter is particularly reactive due to its fine particle size and in certain conditions may be combustible. Newly placed or well-compacted fill may also have higher gas concentrations.
- Geotechnical specifications: the draft guidelines now include a section on geotechnical considerations for management of HGG. Consultants should be aware of geotechnical specifications of a site, methods for preventing ground settlement and how this may inform designing ground gas mitigation systems. The draft guidelines note that this is particularly so given the increasing trend for low-density residential development on historically filled land. In assessing geotechnical specifications of a site, consultants should consider types and amounts of settlement, settlement monitoring and prediction and compaction trials, amongst other factors.
- New independent review requirements: consultants should also be aware of the need for independent review of gas protection measures. The selection, design, implementation and testing of protection measures should be independently reviewed and verified. Further, consultants should conduct post-construction validation testing and ensure any environmental management plan associated with a site provides for regular independent review and reports on its implementation.
The HGG Guidelines will replace the existing Guidelines for the Assessment and Management of Sites Impacts by Hazardous Ground Gases (2012).
Following the public exhibition period, both guidelines are expected to be implemented this year.
Lodge a submission
The EPA is seeking feedback on whether the draft guidelines:
- adequately achieve their purpose;
- contain up-to-date and relevant information; and
- are useful and user friendly.
To make a submission by 8 October 2019: