Void filling – Mineshaft fill – Middlesbrough, United Kingdom.
In 2016 we were approached by a joined force of the local councils and mountain rescue of the area to fill a sunk vent shaft of an old mine that created a dangerous hole in the ground.
To fill this mineshaft we used a combination of two of our hardfoams;
RG30 & RG50
What is this hole?
In the last century there used to be a big mining industry in this area that got closed down and flooded.
The mine was no longer accessible and to completely block it from public access.
The vent shafts were covered with wooden beams and on top a landfill was made. For years and years peoples waste was placed on top of these mines.
After many years the wood started to rot, and the rising and sinking water levels in the mines started to drag in debris from the landfill. This was weakening the structure and eventually created a sinkhole about 12m wide and 30m deep!
So, what was done to it now?
Because of the fear of people falling in (even though it was a restricted area) the hole needed to be filled to prevent further damage to the surroundings and possible casualties.
Various methods were discussed, but none were possible due to accessibility or in any way affordable.
Because we have the possibility of placing a stand alone unit on site, and bringing the resin and hardener to site in small quantities after which the foam is made. We could do the job with relative ease as long as the logistics to the shaft could be fulfilled. And with the help of some of the local mountain rescue crew this was done with relative ease.
How long did this take?
Done in 2 phases, the overall time of the filling took 3 weeks including setting up and breaking down twice.
Unlike other products that you can only fill up 50cm per day, or products that create great temperatures when applied in big quantities. Our foam is easy to apply in large volumes at a time.
This meant that we could fill 3-5m per day depending on the width and how much daylight we had to work safe.
The shaft was filled with 2 densities of foam; RG30 to fill up the biggest mass and RG50 for the meters at the top to secure a safe and strong structure at surface levels.