In early 2019, WBHO approached Erizon to undertake 5.5 hectares of soil stabilisation and revegetation for a major highway upgrade on Old Cooma’s Road, within the Queanbeyan regional council area, located in the southeast of New South Wales.
Erizon’s environmental consultants met with WBHO personnel in early May to inspect the location and conduct a 3D drone survey of the land topography to determine the amount of product required to cover the area.
Given the soil disturbance and lack of appropriate topsoil storage, Erizon was concerned with the condition of the remaining soil and therefore conducted a soil analysis which revealed the following results:
+ Both exchangeable and soluble magnesium were extraordinarily high, which resulted in low calcium and potassium. This imbalance was likely to have a significant impact on nutrient availability to plants and have an impact on the soil’s physical characteristics.
+ Phosphorus, nitrogen and potassium were low in all samples.
+ All trace elements except iron were deficient.
+ Organic matter content was incredibly low.
Based on the comprehensive assessment of the site and the soil analysis results, Erizon proposed a solution that supported WBHO’s stabilisation and revegetation goals for the roadside cuttings and field batters, while meeting the relevant Road and Maritime Service (RMS) standards. The following recommendation consisted of agricultural additives to promote soil stabilisation and vegetation growth:
+ EnviroSoil – hydraulic biotic soil amendment
+ Native seeds blend
+ AgCalcium Boost
+ Custom fertiliser – Di-Ammonium Phosphate (DAP)
+ EnviroLoc – Hydromulching Bonded Fibre Matrix (BFM)
Due to the lack of microbial activity and nutrient deficiencies found in the soil, calcium, EnviroSoil, fertilisers, and hydromulch were integrated into the soil stabilisation and rehabilitation program.
1. Calcium: In support of EnviroSoil, the AgCalcium Boost, designed to help break down the soil properties and enhance the active botanicals in the soil, was applied first.
2. EnviroSoil: The foundation of the proposed solution was a hydraulic topsoil alternative for depleted soil that supports vegetation growth. With eight active components, EnviroSoil can revive lifeless soils and facilitate germination and plant growth even under severe conditions.
3. Fertiliser: Nitrogen, phosphorus, potassium, sulphur, and additional trace elements were required to balance the soil deficiencies.
4. Hydromulch: The mulch fibres delivered up to 50% more water holding capacity which displaced optimal water filtration around the seed. The mulch also provided a protective erosion control cover which assisted in maintaining optimal temperature, water filtration for optimal seed germination, and helped suppress weed growth.
One of Erizon’s specialised HydroRigs was used for this project. The hydraulic cannon attached to the HydroRig provided the technicians with the flexibility to adjust pressure rates to ensure application consistency and uniform delivery. The internal agitators within the holding tank ensured an even application by consistently mixing the product.
The project started with an initial 3D drone survey which recorded and mapped the area to a high degree of accuracy. Based on the analysis of the site conditions and soil profile, a tailored three-phase remediation program was developed in line with the client’s goals.
The first phase consisted of the hydraulic application of a calcium solution on the subsoil at rates that gave an equivalent response to applying 4-5tonnes/ha of Ag Lime. The calcium properties changed the soil profile and rendered it susceptible to breaking down. This step also assisted in the second phase of the program by supporting the active botanicals in the EnviroSoil.
The second phase consisted of the hydraulic application of Envirosoil, combined with fertilisers and RMS specifications approved native seed blend for an optimal growing environment.
The final treatment phase included the EnviroLoc hydromulching solution, along with binders and supportive fertilisers.
In support of these three phases, Erizon worked closely with the team at WBHO to assist them with a supplementary irrigation plan. The recommendations considered local climate conditions to ensure the best possible outcome for the project.
Erizon encountered and addressed the following problems throughout the duration of the project:
Location – The team was required to maintain duties while working in and around the existing plant, equipment, and contractors completing earthworks within the same area. Proactive communication with the client and their personnel resulted in the success of the project.
Weather – Strong winds required strategic planning of application to eliminate the possibility of overspray and loss of product.
After the final sign off from WBHO, the feedback implied that the client was impressed with the coverage, application, and engagement with the team as a whole. Within the first month post-application, there had already been signs of agricultural growth, and the results to date show that the revegetation project had been a success.
Please note we do not service Residential Projects.