When it comes to property development, the growing disposal costs have led to a need to manage all soil waste; this is especially true with contaminated soil. Depending on the risk profile of the soil, disposing of contaminated soil can cost anywhere between $200 and $1,000 per tonne? For clean soil, this reduces to $20 to $60 but can still provide financial concerns. With a basement car park as an example, this can easily exceed a few thousand tonnes and therefore highlights the need for efficient soil waste management.
Under current New South Wales regulations, illegally accepting and disposing of contaminated soils can lead to heavy fines. Yet, this isn’t the only reason for the two main regulations; the Protection of the Environment Operations (Waste) Regulation 2014 and the POEO Act (Protection of the Environment Operations Act 1997). Additionally, the two Acts aim to reduce disposal costs and encourage soil reuse.
Today, we want to discuss the waste disposal framework in more detail and what it suggests to all in the industry!
Waste Disposal Framework
Thanks to the Waste Avoidance and Resource Recovery Act of 2001, we have an important steps to follow and the framework helps to promote and implement the following;
Step 1: Waste avoidance
Step 2: Resource recovery
Step 3: Disposal
Step 1: Waste Avoidance
To prevent the need for steps two and three, the first step would be to avoid as much waste as possible. How can this be achieved? Through a balanced cut and fill plan. If at all possible, the need for cut and fill can be avoided by cleverly designing the existing topography of a site.
Step 2: Resource Recovery
There are three stages to resource recovery; onsite reuse, offsite reuse, and soil recycling. With the first two in mind, onsite reuse is the preferred option whenever excess soil is excavated. Therefore, the aim should be to maximise onsite reuse through;
- Assessment of the contaminated fill and whether there’s an opportunity to reuse without negatively affecting either the environment or human health (a risk assessment specific to the site should be conducted).
- Assessment of whether contaminated soils can be reused as fill (through onsite remediation).
- Improve the reusability of all soil by filtering/screening all construction waste and other debris.
- Utilising an onsite containment cell to manage contaminated soils (this must adhere to the restrictions while also offering the documentation required by law).
What about offsite reuse? In this regard, all uncontaminated natural soil that doesn’t contain acid sulphate soils, natural asbestos, or sulfidic ores, can be reused offsite since this is considered VENM (Virgin Excavated Natural Material).
In an attempt to keep costs to a minimum, certain occasions may allow for offsite disposal of VENM instead of other soils when excavating a borrow pit. In the resource recovery framework, other offsite reuses of waste soil are regulated including the safe reuse of selected wastes after resource recovery exemptions. Perhaps the most common and well-known exemption to soil waste is ENM (Excavated Natural Material); in this exemption, the reuse of soil waste is facilitated when suited towards earthworks and engineered fill. However, to ensure soil meets the correct ENM requirements, it must go through an extended testing process.
If resource recovery exemptions aren’t met despite a soil’s suitability for offsite reuse, a site-specific resource recovery exemption application may be sent to the NSW EPA.
Finally, the third aspect to resource recovery is soil recycling and this is recommended when soil hasn’t qualified for offsite reuse under specific resource recovery exemptions. Under the POEO Act, every soil recycler in NSW will have an individual license which states the criteria soil waste must meet in order to be accepted. With this in mind, there’s no standardised set of requirements for all recyclers. Even with ‘GSW Recyclable’ and ‘Recyclable Soil’, these are not standardised waste regulations under EPA or NSW law.
Step 3: Waste Disposal
If soil wastes cannot be used onsite or offsite and they cannot be recycled, the only solution remaining is a landfill (which is why soil waste avoidance is so important). Even if being disposed, soil waste still needs to be classified under the Waste Classification Guidelines from the NSW EPA. While following the correct disposal methods can be expensive, any landowners who accept contaminated fill or illegally dispose of the material can receive big fines.
Depending on just how contaminated the soil may be, most fall within three categories; GSW (General Solid Waste – non-putrescible), HW (Hazardous Waste), and RSW (Restricted Solid Waste).
If asbestos is found within soil, this falls under Special Waste and needs to be noted as such when disposing of the soil in a licensed landfill facility. For example, it could be considered Special Waste (Asbestos) in the RSW classification. As long as the soil waste is classified correctly, a licensed landfill facility is the only acceptable destination for the material.
Soil Assessment Procedures
Before any soil waste can be disposed legally, it needs to be assessed by a professional and qualified consultant; they will provide any relevant exemptions and classifications. If you have any questions or concerns regarding this process, you aren’t alone. Therefore, you can find more information on our website or you can contact us directly.
At Geo-Logix, we have contamination experts who can ensure you follow the regulations correctly when dealing with soil waste disposal. For more information, feel free to browse our website or call Ben Pearce at 02 9979 1722!