CASE STUDIES
Growgrass™ has a proven track record of reliability, timeliness and excellent performance on complex projects.  If you have a difficult site to rehabilitate, we have the capability and experience to take care of it for you. Take a look through these case studies.

Toowoomba Range 

Using: Organic Growth System (OGS) & Earth Matrix Binder System
Date: July 2014.  Location: Toowoomba Range. 
Project: Re-vegetating Road Side Batters
Scope of works: Establish vegetation on existing substrate. All topsoil was removed from site due to weed infestation issues.
Site Specific OGS. The Process: Perform soil analyses to determine the overall soil health. From the soil analysis we learned PH was excessively high 8.4, with general low soil fertility and available plant nutrition. Organic carbon levels were also very low.
  • Pass one was designed to quickly lower the PH to desirable levels with a daily watering requirement to drive the PH Reducer into the substrate, daily PH checks were taken until desired target PH levels were reached.
  • PH was correct within 3 days, enabling pass 2 to be applied which included carbon boost designed to boost organic carbon levels.
  • Hydro Bio gypsum with boosted organic phosphorous, Compost plus soil conditioner, Hydro fertiliser, and Hydro BIO N for long term nitrogen fixation.
  • The Hydromulch slurry (EnviroStraw HGM Plus) was then applied at 6 ton per hectare rate with seed and the Earth Matrix Binder System (Growgrass Pty Ltd) proprietary binding system.
Maintenance: Water three times a week for 8 weeks, at the last watering apply Hydro Max long-term chelated organic fertiliser. 

Xstrata New South Wales  

Using: GeoSpray
Date: April 2014. 
Location: Tahmor New South Wales
Project: Stabilising Railway Batters
Scope of works: Stabilise loose shale and rock and minimise erosion.
Process:
  • Spray GeoSpray Extreme, providing 100% ground coverage.
  • Three passes of Geospray Extreme were conducted.
  • Each pass consisted of a 1kg/m2 each pass being sprayed from multiple directions ensuring 100% coverage is achieved.
The Result:
The applied GeoSpray Extreme cover has been 100% successful, exceeding client's expectations.
Four hours after application a freak storm passed over the area bringing with it strong winds & torrential rains exceeding 50mm/hr for two hours.
GeoSpray Extreme, even with the limited curing time, performed beyond its limits and was found intact and un-effected by the storm.
"The applied GeoSpray Extreme cover has been 100% successful, exceeding client's expectations."

Wiggin Island Rail Loop  

Using: EnviroStraw OGS (Organic Growth System).
Date: April 2013.
Location: Wiggin Island Gladstone Queensland.
Project: Wiggin Island Rail Loop.
Scope of works: Establish vegetation to minimise erosion without importation of topsoil.
Substrate: Compacted clay.
Process: Perform soil analyses to establish soil health and fertiliser requirements. Ameliorate the soil prior to the application of the Hydro Mulch Application.
Amelioration: Two passes were made in the hydromulch machine, applying the inoculants listed below. These were designed to:
  • open the hard clay soil,
  • improve soil health,
  • neutralise PH,
  • build Humus for long term vegetation establishment, and
  • improve water holding capacity, cation exchange and soil friability.
Inoculants: Hydro Carbon boost was used to open and soften the clay and raise organic carbon levels. Hydro PH Booster was included to raise the PH to acceptable levels. Organic NPK slow release fertiliser was used for long term plant nutrition. 
We also added Hydro Bio Boost — a high analyses microbial inoculant with included N fixing microbes — and Hydro Max to provide complex carbohydrates and amino acids for Microbial health and immediately available plant nutrition.
Hydro Mulch EnviroStraw HGM was added at a rate of 10 ton to the hectare with included soil conditioner to further build the organic carbon levels. Water maintenance was ongoing for a 10 week period during and after the application process.

Snowy Mountains National Park

Location: Snowy Mountains National Park ACT.
Project: Revegetate cut batter 1-1 Slope.
Method: Organic Growth System. OGS.
Substrate: Loose Shale and Rock and Volcanic Soil.
Project Date: February 2014.
Contractor: Grow Grass Pty Ltd.
This project required application of a non-watering hydromulch. The process included three passes with Pass 1 being seed and soil ameliorants. 

We focussed on the inclusion of organic carbon, along with a high ratio of soil conditioner and microbial additives. Rain was not expected on the site for several months so the binding system was important. 

The OGS system was utilised: Eight ton of EnviroStraw Hydromulch with added soil conditioner and HydroGrip Powdered Binder. The final pass included a heavy application of EnviroBond Emulsion soil mulch stabiliser to ensure the Hydromulch remained in place long-term waiting for rain to provide the moisture to germinate the grass seed. Watering was simply not an option.
Rain was not expected on the site for several months so the binding system was important.

Tumbulgum Tweed Coast Batter

Location: Tumbulgum Tweed Coast. 
Project. Revegetate batter 1-1 slope.
Method. OGS non watering.
Substrate. Compacted clay, rock.
Project date. November 2013.
Application contractor Grow Grass Pty Ltd.

The Batter was reshaped after a severe storm caused it to slip. The batter had been reshaped and had applied GeoSynthetic matting applied to the top 3rd of the batter. Remainder of the batter was to be stabilised long term by establishing vegetation. Challenges included low grade substrate with nil topsoil, it was also impossible to include a watering program. 

A non-watering OGS system was applied at 6 ton rate to the hectare which included 3 passes of the application equipment. 
  1. Pass 1 included organic carbon (Carbon Boost) designed to soften the clay allowing water penetration, other amelorants used included a wetting agent, organic fertiliser, soil conditioner, and microbial additives along with a blend of native grass seed and the NSW Tweed Shire Council seed mix. 
  2. Pass 2 was EnviroStraw BFM. 
  3. Pass 3 included EnviroStraw BFM with added EnviroBond Emulsion Binder. The application process was completed early afternoon with a heavy rain shower received on site that evening. On inspection the next day the OGS system was 100 % intact.
The batter had been reshaped and had applied GeoSynthetic matting applied to the top third of the batter.
Vegetation grew through to stabilise the slope long term.
On inspection the next day the OGS system was 100% intact.

Snowy Mountains Highway batters

Project location: Snowy Mountains Highway, Talbingo, 50km from Tumut heading towards Cooma.
Project description:  To stabilise 1:1 H:V cut batters. 
Substrate:  Highly weathered siltstones, shales and mudstones.
Method: Apply 3-4 kgs of GeoSpray to provide 100% protective cover.
Project date: Early June 2014.
Application Contractor: Grow Grass Pty ltd.

During consultation with the client the location and the lack of organic matter on the batter it would have been difficult to Hydromulch the batter to ensure long term stability. 

GeoSpray was mixed and applied at an average 3 kgs per square meter making 2 passes of the application equipment.

The batter is about 180m long and the average length of batter is about 9m. It is around 1:1 H:V in highly weathered siltstones, shales and mudstones and is easily rippable.

The batter also attracts a large amount of sun.  The altitude would be around 800m at this location so it is reasonably cool.
BEFORE ...
AFTER ... Photos taken September 30, 2014
"The project has been a complete success"
BEFORE ...
It would have been difficult to Hydromulch the batter to ensure long term stability because of the location and the lack of organic matter.
AFTER ... the project has been a complete success.
Photos taken September 30, 2014
GeoSpray is performing well and as you can see from the photos, very little rock has fallen despite the slope having been scaled just before the application of the GeoSpray. There are still no signs of erosion of the GeoSpray at this stage. 

Santos GLNG

Project description: To apply a non-watering hydromulch option on the GLNG pipe line.
Substrate: Dispersive Sandy loam.
Method: Apply 4 tons EnviroStraw Plus Hydromulch with added EnviroBond Emulsion Binder.
Challenges included: Difficult access. 4WD Hydromulcher required.
Notes: Due to access difficulties watering of the applied hydromulch was not an option. The design was for a single pass of the hydromulcher including mulch seed, fertiliser and binders. Some amelioration of the substrate had been performed prior to application of the Hydromulch slurry.
How's that for binding? We had to control the erosion to give the grass a chance to grow ... and as you can see ...  left and right  ... it did!
Due to access difficulties watering of the applied hydromulch was not an option.

Cockatoo Coal 

Despite the hot dry conditions and strong winds blowing most days, we managed to get the seed to strike.
Project date: May 2014.
Project description. To revegetate 17 hectares of levy wall. Batters were >3-1H and up to 30 meters in length.
Substrate: Black clay.
Maintenance: Project was to be watered for 8 weeks or until satisfactory vegetation was established.
Specification: 4 ton per hectare of EnviroStraw plus hydromulch, 80 kgs per hectare of hydrogrip plus binder. Included Organic fertiliser, Gypsum and Huma Boost soil microbial additive.
Notes: The project had a small window of opportunity to complete the project, so we mobilised  2 Hydromulching units to ensure the deadline was met. The contract went without a hitch from our team. But the challenge was always going to be keeping enough water on the applied Hydromulch to establish vegetation. It was hot dry with strong winds blowing most days making it very difficult if not an impossible task to keep adequate water on the applied hydromulch.