Case studies

Subsoil application

Canungra, QLD

The challenge

R Johnson Contracting asked EnviroStraw to make a recommendation for the application of a hydromulch medium on a newly constructed fire-trail, which was developed around a housing development project at Finch Road, Canungra. With no soil science provided, and no topsoil available, we undertook a site visit to ensure the appropriate recommendations could be done.

Part of the fire-trail road traverses extremely steep sloped areas that need high-end soil erosion-control products that give immediate and effective control, but also allow for the natural erosion-control mechanism to be activated – ensuring long-term stability is achieved in the shortest time-frame. The steep areas also required speciality hydromulch equipment, in the form of a 4WD machine that could traverse the slopes, and a no-watering solution was required as watering via a water truck simply wasn’t possible.

23 July 2020 - Site inspection prior to treatment

23 July 2020 - Site inspection prior to treatment

The solution

After a full assessment of the project, EnviroStraw recommended the use of EnviroMatrix® ECM, with Envirobond – our long-term storm-guard soil mulch stabilising polymer – as the preferred hydromulch medium and additional soil erosion-control agent, in order to minimise the risk of failure.

As no topsoil was available for spreading, EnviroMatrix was applied directly to the subsoil at a rate of five tons to the hectare. Since watering was not possible, 400 litres of Envirobond with native seeds was then applied.

As Grow Grass have a six-wheel-drive hydromulcher that’s capable of traversing the steep on-site slopes, they were engaged to quote on applying the EnviroMatrix®ECM hydromulch medium, with suitable plant-seed species as recommended by a local South-East Queensland seed supplier. Due to the effectiveness of this technology the Grow Grass quote was accepted, and the product was applied once climatic conditions improved and it was possible to access the site.

The results

Products were applied on 23 July 2020 and follow-up site visits will be done over the next 6-12 months, to monitor the performance of the BioGrowth revegetation program and ensure the desired outcome is achieved in a timely manner.

20 August 2020 - Cover crop establishment from natural rain events.