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What Is Remediation?

Contaminated Land Remediation - Perfect Remediation

By Daniel Green

One of Murphy’s Laws states that: left to themselves, things tend to go from bad to worse. You can see this across the globe – everything is eventually reclaimed by mother nature. Not so sure? Don’t mow your lawn for a month and see what happens. This naturally occurring deterioration needs corrective action, hence the need for repair.

Refurbishment.

In 2018/2019, Perfect Contracting spent more than 18 months doing a little hard but mostly soft demo on the 33 floors of Westpac Bank’s Kent Street office. There was a bunch of jackhammering with a full soft strip out and rubbish removal. Would these upgrades make the tenants’ life easier? Definitely. Was the building deteriorating to the point it was not functional? Not even close.

We see refurbishment as building improvements such as: changing its intended use, updating its appearance, altering layouts, and upgrading finishes/fixtures/fittings – all work to enhance the space. However, during refurbishment, there are often surprises laying in wait, that in many cases need remedial works or repairs: damage due to a loss of waterproofing integrity, rising dampness, concrete cancer, and so on.

Remediation.

In 2019/2020, Perfect Labour Hire sent crane operators, riggers, and boilermakers to Ingleburn Reservoir for Freyssinet Australia on behalf of Sydney Water. The tank was stripped down to its shell – all interior linings and pipework were removed, all components were media blasted back to raw steel, everything was recoated and all new valves & pipes were installed. Heck, the tank even got a new roof. Would these upgrades make Sydney Water’s life easier? Definitely. Was the reservoir deteriorating to the point it wasn’t functional? Also yes.

Build It And They Will Come.

Joe public has a tendency to believe that the manmade structures towering above them will last forever – and some of them actually will. The Colosseum case is in point. However, without Roman budgets and the slave labour to do it, modern commercial buildings have a far shorter lifespan and lifecycle. It’s usually just 50 – 60 years. Within those five or six short decades are various stages of decay:

  • Years 1 – 15. The building is brand new and everything works, so the first owner/occupier often does very little maintenance.
  • Years 16 – 30. 15 years of [ab]use and neglect see the need for an overhaul across almost all systems.
  • Years 31 – 49. These last 19 years often consist of major overhauls and upgrades to the point of becoming commercially unviable.

Deep Seated Issues.

The safety of the public and workers, or a loss of functionality of some or all of the assets is usually the primary motivator for remedial works. And while these works are often critical to bringing the operation back online, there is not always an imminent need for them. Some common types of deterioration are:

  • Mortar/masonry disintegration.
  • Metallic corrosion.
  • Timber delamination.
  • Surface coating degradation.
  • Bacterial infection.
  • Concrete cancer.
  • Structural stressing and/or cracking.
  • Joint and/or sealing failures.
  • Glazing issues.
  • General elemental damage.
  • General moisture damage.
  • Chemical damage.
  • Radiation.

Root Causes.

There are a myriad, if not an infinite number of causes that lead to remediation and rectification works. There can be a singular cause or multiple causes, or even a chain reaction of causes. Some examples:

  • Lack of maintenance.
  • General wear and tear.
  • Building misuse or conflict.
  • Substrate articulation.
  • The organic material invasion via trees, vines, and/or roots.
  • Poor/incorrect initial construction methods, testing, and/or approvals.
  • Exposure to salt air and water.
  • Weather events like storms, harsh and/or prolonged sun, heavy and/or lengthy rain, and/or snow.
  • Seismic events.
  • Incorrect building materials.
  • Poor drainage.
  • Antiquated systems like HVAC, power modules, etc.
  • Poor tenancy or operating procedures.

Get Your Fix.

So what is the solution? That is a good question and unfortunately, the answer is that it really depends. Sometimes the solution is easy. Say your gutters are blocked causing rainwater to back up and enter your home. The solution is easy – you clean your gutters. But what if your settlement-era foundation sandstone is throwing a tantrum or your nuclear power plant is having a meltdown? The more complex the issue and the larger the scale – the more detailed the assessment and the more customised the approach. For example:


Structure – Residential home.
Symptoms – Cracking concrete foundations.
Cause – Nearby trees.
Details – Upon further investigation, the real reason was not root invasion but moisture leeching, causing foundation influences. This destabilised the substrate on only one side of the property, causing part of the house to tilt resulting in compromised slab integrity.
The Fix – Council didn’t approve tree removal, so a deep, narrow trench was dug and a concrete barrier was poured accompanied by chemical root inhibitors. The inconsistencies in slab height were remedied with grout injection.


Structure – Underground tunnel wall.
Symptoms – High-pressure water invasion via 0.25” aperture.
Cause – Tunnelling below the water table.
Details – Investigation revealed that this was one of many expected leaks due to the substrate material and tunnel depth.
The Fix – A flexible, long-lasting, fast-setting, waterproof polyurethane resin was injected into the hole which ceased the flow.


Structure – Public park sandstone wall partial collapse.
Symptoms – Tumbling sandstone, cracks.
Causes – Shifting substrates due to prolonged excessive rain, invasive tree roots, nearby heavy vehicle traffic, and an exceeded lifespan.
Details – Investigation saw that due to tree root invasion, consistent rain over several decades, the upgrade of a nearby road to accept heavy vehicle traffic, and the age of the initial construction, the existing rock anchors had exceeded their capabilities.
The Fix – All trees were removed, new rock anchors were installed and the entire wall was shotcrete.

Common Repair Methods.

When there’s no singular cause there’s no singular solution. The repair process depends heavily on several considerations gathered during a detailed assessment. Some corrective actions are:

  • Crack injection
  • Rock anchors
  • Shotcrete
  • Blast and Paint, followed by recoating
  • Cathodic protection
  • Grout injection
  • Removal of contaminated materials: caulking, ACM’s, PCB’s
  • Chemical injection
  • Damp proof course
  • Fireproofing of building materials
  • Joint rectifications
  • Waterproofing
  • Applied paint systems
  • Structural strengthening
  • High-pressure washing
  • HPWJ/concrete demo
  • Generalised concrete repairs
  • Retaining/shoring/structures
  • Soil remediation and capping
  • Hazardous material remediation

The Last Word

If you have noticed some potential issues that may need remediation then Perfect Remedial can help. Because as Murphy told us, left to themselves, things tend to go from bad to worse.

For more information on our services, take a look at our webpage or request a free quote.

contact us today