Using proven ground engineering and asset rehabilitation techniques, councils and other asset owners can extend the life of public assets and eliminate the need for replacement.

Mainmark offers a range of advanced, environmentally-inert solutions that significantly reduce capital works expenditure and improve public safety.

Ground subsidence, deteriorating concrete and steel infrastructure, and broken pipelines can cause dangerous public safety issues and expensive damage to public utilities and infrastructure.

We repair assets for electricity, gas, waste management, and telecommunication providers, as well as water authorities. Our methods are environmentally inert and designed for fast, easy application. They don’t usually require excavation, so disruption is kept to a minimum and worksites are left in their original state. Depending on project requirements, sites can often be returned to full operation within a matter of hours.

Mainmark can:

Fill large underground holes and voids quickly and cost-effectively with Terefil, our advanced engineered lightweight cementitious fill

Revitalise, seal, protect and structurally reinforce ageing or damaged manholes, tunnels, lift shafts, pipes, tanks and drains with site specific Specialised Resins, Gels and Coatings

Raise, re-level and re-support civil and public assets using our proprietary Teretek engineered resin solution

Re-support and re-level large, complex public infrastructure using the award-winning JOG Computer-Controlled Grouting technique

Compact and stabilise slopes and embankments to control erosion and provide safer site access using Permeation Grouting

Areas of service include:

Strengthen ground and re-level public infrastructure

Mainmark’s injection technologies are cost-effective, non-invasive methods for re-levelling, re-supporting buildings and on-ground structures of all sizes. We offer resin injection and grouting solutions for compacting and strengthening ground to raise structures and stabilise lose soil.

Success Story:

Raising the bar in ground engineering innovation

Mainmark helps The Seaview Wastewater Treatment Plant meet the 55% New Building Standards using Terefirm. Terefirm is a proven, non-invasive, ground improvement and liquefaction mitigation technique that is validated by geotechnical testing. The technique is applied with surgical precision in a noninvasive and relatively clean process to densify soil and increase liquefaction resistance.

Success Story:

Keeping power stations up and running

A mains pipe had ruptured three metres under the concrete floor of a power station, causing cracks to open up and fines to be washed away from the cooling water circulation system under the floor slabs. A lack of floor support meant that the 60-tonne cranes required for the power station’s routine maintenance program couldn’t access the station. Mainmark was engaged to consolidate the foundation ground and re-support the site’s concrete floor without raising it. Mainmark applied its resin using a deep-injection technique through small injection tubes in the concrete until all sections of the floor were re-supported and all cracks in the cooling water system inspection pits has been sealed. Heavy cranes were able to drive over the area just 30 minutes later.

Void filling


Mainmark has a number of void fill solutions such as polyurethane and cementitious grouting. We assess each situation to determine the best course of action and the best material to use. Smaller voids in underground rock strata are generally filled with a void filling foam or concrete void filler; a material like urea silicate or polyurethane resin that not only fills the void but also ‘glues’ the surrounding rock together.

When greater supportive strength is required, such as for retaining wall backfill or large voids, Mainmark’s Terefil® solution can be applied. A lightweight polymer modified cementitious-based void fill material, Terefil can be used for massive voids that require filling quickly and economically. This versatile engineered material is ideal for use as a fill in situations where cellular concrete, foam concrete or foam cement would otherwise be applied. Terefil’s capabilities as a structural fill far surpass those of traditional granular fills or aggregate materials. The highly flowable grout can be pumped efficiently over long distances to overcome limited site access and meet tight project timelines.

Typical uses:

  • fill large holes and voids
  • obsolete tanks
  • abandoned pipes and decommissioned culverts
  • mineshafts and tunnels
  • sinkholes
  • landslip repair
  • backfill for retaining walls and trenches


Terefil® mix can be pervious or impervious to suit the application, forming an effective permeable subgrade beneath roads, highways, airport runways and sporting facilities. It will flow into spaces to fill voids with zero bleed and exhibits shrinkage of typically less than 0.1%-0.3%.

Success Story:

Returning a fatal weir to safety.

Mainmark applied Terefil to fill a dangerous void at a weir in South Dubbo that had been the site of nine fatalities since its construction in 1942. The void needed to be filled to restore structural integrity to its apron, creating a shallower and less turbulent pool of water. Mainmark successfully filled the void within three days, working around heavy water flow.

Rehabilitate ageing assets

Our innovative range of protective resin and gel coatings provide exceptional environmental, chemical and abrasion resistance to protect the long-term structural integrity of civil infrastructure and building assets including manholes, tunnels, lift shafts, pipes, tanks, drains and basements.

Success Story:

Rehabilitating a steel pipe under three factories with no excavation

Mainmark successfully rehabilitated a two-millimetre thick galvanised steel drainage pipe that was heavily corroded and had collapsed under heavy traffic from the factories located above it. Structural expanding resin was first injected to re-align and structurally support the pipe, and then ENCAP6 was applied to rehabilitate it. This method eliminated the need for expensive excavation, renewal, or diversion of the drain, delivering significant cost savings for the council.

Stabilise ground

Permeation Grouting

Permeation Grouting can stabilise lose gravel, sand and other non-cohesive soil to provide safer access for crews during public utility extensions and renovations, demolition, landscaping, and underground and above-ground construction. It reduces the permeability of granular soils to create ground cohesion. This remedies erosion and prepares sites for excavation.

Success Story:

Rehabilitation of Stormwater Chamber

A stormwater pit and embankment in Gardyne Street, Bronte, New South Wales, was experiencing structural problems due to the ageing infrastructure. Storms and malfunctioning plumbing mains had caused a large area of road to collapse and subside. An adjacent house had also experienced settlement because of the erosion. Mainmark successfully addressed the structural and ground stability issues faced by the council in just two weeks.