On the Toronto Eglinton Crosstown East tunnels, our mobile slurry treatment system turned jet grout backflow into roughly 1,120 m³ of clear water, reused on site and discharged to the sanitary sewer with no extra processing.
Tunnelling & Microtunnelling
Keep the fluid circulating. Keep the bore advancing.
Stage 3 Separation (S3S) is your TBM and microtunnelling slurry partner. We separate slurry and spoils at the portal, keep the bentonite and polymer in circulation, and make sure muck handling never sets the advance rate.
What on-site separation does for the drive
Fluid keeps circulating. Muck leaves dry.
A slurry TBM only advances as fast as its separation plant returns clean fluid. Settling pits and vacuum trucks put that loop on the critical path. S3S brings the plant to the portal and turns the return flow into fluid you pump straight back to the face.
The BE-300 slurry treatment plant is modular, so throughput scales with the drive. Add units for a bigger machine or a faster advance rate, and it still lands on a compact container footprint.
On-site separation cuts what leaves the portal. Slurry becomes dry solids and reusable fluid, so the volume you haul and dispose of drops sharply.
Three decades and more than 7,500 projects across energy, construction, industrial, municipal, and dredging. We've run into your slurry problem before.
How a drive runs
Return flow in. Circulating fluid and dry muck out.
TBM and microtunnel return flow, HDD mud, and bentonite and polymer slurry come back as a continuous, high-volume stream. S3S receives it, separates it in stages, and returns fluid at the density the machine needs. One crew owns the whole loop.
01
Receive the return flow
Slurry and spoils are pumped straight from the TBM, microtunnel bore, or HDD rig to the treatment system, so the drive never waits on a muck box or a vacuum truck.
02
Desand and dewater
Coarse solids like sand and gravel drop out first. Then centrifuges and site-tuned flocculation pull the fine solids from the slurry, with our operators dialing chemistry to the ground the machine is in.
03
Return fluid, stack solids
Conditioned bentonite and polymer go back to the face at the right density. Surplus water is reused, sent to the sanitary sewer where permitted, or disposed of at a fraction of the volume. Solids leave dry, stackable, and ready to pass the paint-filter test.
The portal advantage
No pits.
No lagoons.
No convoy of vac trucks.
Tunnel portals are the tightest real estate on the job, and they are exactly where haul-off gets expensive and slow. S3S runs a compact, modular plant on the footprint you already have, right where the return line lands.
We're not a rental yard. We engineer the separation train around your ground conditions and run it ourselves. Count trucking, disposal, and lost advance, and the drive usually costs less.
Fits a congested portal
In Midtown Toronto, with minimal space and no room for pits, our mobile slurry treatment system dropped onto the site and processed the jet grout backflow from the Eglinton Crosstown East tunnels in place.
Keeps muck off the critical path
Dry, stackable solids and reusable fluid mean far fewer loads on public roads and no settling pond feeding a fleet of vacuum trucks, so the advance rate is set by the machine and not by the muck.
Reuses bentonite and polymer
Mechanical separation pulls the fine and colloidal solids that gravity settling never drops, which is what keeps support fluid reusable across a whole drive instead of thickening into waste halfway through.
One platform. Every kind of bore.
01
Tunneling & microtunneling
02
HDD & trenchless
03
Deep foundations & shafts
04
Jet grout & diaphragm walls
Built for tunnel slurry
The equipment we bring to the site
Every deployment is configured to the fluid, the flow rate, and the footprint. On tunnelling work that usually starts with the BE-300 slurry plant, backed by centrifuges, tanks, and a lab-tuned chemistry program that holds the fluid in spec across the drive.
BE-300 slurry treatment plant
A compact, container-framed desanding and dewatering plant built for construction, tunneling, and dredging. It handles high-volume slurry on a small footprint and integrates with our patented dewatering system for ultra-fine filtration.
- Capacity
- Up to 300 m³/hr, scalable in series
- Best fit
- TBM, microtunnelling, HDD, pipe jacking
- Footprint
- Compact container frame
- Pairs with
- Patented dewatering system
Where we run and what we treat
Staged across North America. Built for the drive.
S3S stages equipment and crews across the continent so the right plant is close to the portal, not five days away. The same model runs everywhere: engineer the separation train, operate it on site, measure the result.
Houston, TXGulf Coast operations and support
Midland, TXPermian Basin equipment yard
Calgary, ABCanadian infrastructure coverage
North DakotaBakken field deployment
TBM slurry separation
Slurry TBM return flow desanded and dewatered at the portal so conditioned fluid goes back to the face and the machine keeps advancing.
Microtunnelling & pipe jacking
Microtunnel and pipe jacking spoils treated on site, so a congested launch shaft never turns muck handling into the critical path.
Bentonite & polymer reuse
Fine and colloidal solids pulled from the support fluid so bentonite and polymer stay in circulation across the whole drive instead of thickening into waste.
HDD & trenchless
Bentonite drilling mud and cuttings from horizontal directional drilling, treated for reuse or reduced-volume disposal instead of hauling every gallon.
Proven on the
biggest tunnelling
jobs on the continent.
Case studies ↓
Toronto Eglinton Crosstown East Tunnels
In congested Midtown Toronto, with no room for pits, our mobile system turned jet grout backflow into dry, stackable solids and roughly 1,120 m³ of clear water, reused on site and discharged to the sanitary sewer. Waste handling costs dropped about 20%.
Trenchless, Midtown Toronto
Recycle the fluid, don't dump it
Conventional rental tanks rely on gravity, take days for solids to settle, and eventually thicken the polymer past reuse, doubling the fluid you buy and the tanks you stage. Mechanical separation keeps bentonite and polymer support fluid in service across the whole drive.
Fluid recycling
On site in 24 hours
When a contractor calls, we can be rigged up and running within a day, because we stage ready equipment across the continent and service it before it's needed. For a Toronto job, that can mean trucking a plant hours from a nearby yard instead of days across the country.
Field operations
Gordie Howe International Bridge
On one of North America's longest bridges, our tank system and centrifuges recycled the polymer fluid across 33 drilled shafts. Reusing it instead of hauling it saved roughly 160,000 gallons from disposal every two weeks, and solids left dry and paint-filter clean.
Fluid recycling, Detroit-Windsor
TBM slurry separation
For slurry TBM contractors. We desand and dewater the return flow at the portal so conditioned fluid goes back to the face on schedule. Whatever the dig, we've handled the slurry, and we show up ready to run.
See how we work→Tunnelling applications
A bore advances at the speed its separation plant returns fluid. When the plant falls behind, the machine waits. These are the three places S3S keeps that circuit ahead of the work.
TBM slurry separation
The slurry circuit supports the face and carries the cuttings out, so separation is not a waste-handling job bolted onto the drive. It is part of the drive. S3S sizes the train to the machine's production profile and to the real operating swings rather than one ideal flow number.
The BE-300 handles scalping and double-cyclone desanding at up to 300 m³/h on a 20 by 8 foot footprint, and units combine in series to double or triple that when the drive needs the throughput.
300 m³/hrBE-300 desanding capacity, scalable in series
Bentonite & polymer reuse
Coarse separation gets the sand out. It does not get the clay out, and clay is what kills support fluid. Once colloidal solids build up, bentonite and polymer thicken past reuse and you are buying fluid and staging tanks to hold what you can no longer pump. S3S runs BOS tanks and clear water loops with centrifuges on the fine end, recycling the fluid continuously through the drive.
On urban trenchless work that routinely cuts disposal volume by up to 87%, and the solids leave dry enough to pass the paint filter test.
Up to 87%Less disposal volume on urban trenchless work
HDD & trenchless
Hauling HDD mud off an urban bore is an expensive way to move water. Disposal can reach $600 per 1,000 gallons, and a directional bore makes a lot of gallons. S3S sets up on the entry side and recycles the mud instead: cuttings out, bentonite conditioned and returned, clear water back into the operation. On a tight utility corridor that takes the truck cycle off the critical path.
$600Typical urban disposal cost per 1,000 gallons of mud
Buyer questions
Tunnel and microtunnel slurry separation, answered
It closes the fluid loop. Return flow from the face is desanded and dewatered, then conditioned bentonite or polymer goes back down at the right density. Without it, the machine waits on muck handling and fresh fluid; with it, the advance rate is set by the machine.
Vac-truck haul-off is expensive, slow, and hard to stage at a congested portal, and disposal can run 15-20% of a project's value. On-site separation cuts the volume leaving the gate and takes disposal logistics off the critical path, so the drive keeps moving.
Yes. We treat TBM and microtunnel spoils, bentonite and polymer support fluid, jet grout backflow, and HDD mud. Where the fluid can be reused, we recycle it. Where it can't, we separate it into clear water and dry solids, as on the Toronto Eglinton tunnels.
The BE-300 slurry plant is built into a compact container frame and is modular, so it fits the footprint you already have, no lagoons, no pits, no separate equipment yard. In Midtown Toronto we ran it on a congested site with minimal space.
To the specification your project requires, clean enough to reuse in the operation, discharge to the sanitary sewer where permitted, or meet your disposal criteria. On the Toronto tunnels, recovered water went to the sanitary sewer with no additional processing.
Our systems are modular, so we add units for higher volume or scale down for less. Very short or very small bores can be outweighed by mobilization and trucking, so share the scope and we'll give you a straight assessment.
The slurry doesn't
have to slow the bore.
S3S turns TBM and microtunnel return flow, bentonite and polymer slurry, and HDD mud into circulating fluid, clear water, and dry, stackable solids, on the footprint you already have.
Less trucking. Less disposal. Less coordination. More control over the advance rate.
TBM slurry separation, microtunnelling, bentonite and polymer reuse, and HDD, across North America. One team owns the whole loop.