What is NDD?
Non-destructive Digging, or NDD, is an excavation method that uses a combination of highly pressurised water and air to dig out soil and uncover underground assets such as gas lines, water pipes, cables, etc.
At the very onset, equipment is used to map the underground services on the site to minimise the risk of potential damage. The high-pressure water excavation equipment is used to excavate soil and safely expose underground assets. The by-product that results from this excavation is drill mud or sludge which is collected by a powerful suction hose, usually into a storage truck.
It is important to note, that at times depending on the location of the hydro excavation, the excavated or drill mud may contain contaminants, such as hydrocarbons or PFAS.
Some of the other common terms for NDD include Hydro Excavation, Vacuum Excavation, and Non-Invasive Digging.
Benefits of Non Destructive Drilling
Let’s take a quick look at some of the distinct advantages of NDD.
- A quieter alternative when compared to mechanical digging.
- A faster process results in fewer detours and road closures which often accompany infrastructure upgrades.
- A safer option to expose underground facilities as it uses water and air in comparison to the tools used for mechanical digging.
- Less mess and faster clean-up time, keeping costs low.
- No need for permits before you start the excavation.
What happens to the Mud?
When the excavation area involves relatively clean materials, the NDD mud or drill mud is typically separated into aggregates and water, with both the aggregates and water being reused.
When the work area is found to be contaminated with hydrocarbons or PFAS, the most common method of disposal for drill muds is landfill disposal. The nature of the drilling mud can damage the soil and introduce a possibility of leaching contaminants. These risks see some landfill operators refusing contaminated NDD muds, and it is a relatively unsustainable approach.
With the EPA waste management principles advocating treatment over land disposal, it is a good idea to treat these drill muds so that they can be reused beneficially. The advantages of that are supporting diversion from landfills and the beneficial reuse of recovered wastes.
The Future of NDD is Zero Waste
SOLVE is Enviropacific’s hazardous materials treatment facility built in Altona Victoria. It is Australia’s biggest thermal treatment plant and attracts contaminated material from across the country for treatment.
Our newly launched SOLVE NDD Treatment Plant specialises in treating excavated muds, especially PFAS and hydrocarbon impacted drill muds. We provide an alternative to disposing Non Destructive Drilling waste to landfills and recovering the outputs subject to testing and compliance.
The plant can recover solid wastes such as – sand, gravel, and clays for beneficial reuse, supporting diversion from landfills. The liquid or water recovered from the plant can be beneficially reused in the thermal soil treatment plant at SOLVE, therefore helping reduce the consumption of potable water.
No other existing plant offers treatment of contaminated drill mud to this scale, with the goal that the treated recovery material can be beneficially reused. We are able to ensure NDD can be safely carried out even on contaminated land and are also able to process larger volumes of the drill mud.
The SOLVE NDD Facility will provide an opportunity for the waste to be almost completely re-used and certain contamination destroyed – with the goal that the future of NDD will be Zero Waste. It will provide clients and projects the flexibility to incorporate hydro-excavation (Non-Destructive Drilling) processes into planned projects, abiding by the new EPA waste regulations and increasing safety on sites.