Vacuum excavation is a system which allows material after loosening to be sucked up into a collection tank as the hole slit trench is created the soil is generally broken up for vacuum by and air spade which works very well in none cohesive materials or by hydro power in cohesive materials the system can expose existing pipes and cables without the risk of any damage after removal the spoil is simply tipped into a skip or area provided
Full face safety masks are worn during operation at start of the hole a cone is sometimes used to assist in preventing debris expulsion from the assisting / ground loosening tools, Kill switches are available on the unit and a vacuum release lever allows fast release of suction pressure if required, the unit has full hydraulic tipping to prevent any need for manual handling.
The vacuum unit can achieve depths of up to 2.5m but this will depend on the geology at each location,
The rig stats for access:
- Vehicle Weight = 2 tons empty and Max 3.5 tons full / Width = 2.3m / Height =
Vacuum Assistance Methods Available
None Cohesive Materials
In none cohesive materials such as rubble fill, hardcore and sands and gravels or even softer mixed clayed material an air spade is used to loosen the ground, the air spade is connected to a two tool compressor and when the air spades trigger is depressed the air jet is used to break up & loosen the ground which allows the vacuum unit to remove it, trenches or holes can be created to suit your requirements or specifications
In cohesive materials such as clays a pressure washer and lance with 1m and 2m lengths which is built onto the unit can be used to loosen and break up the material, this then enables the vacuum unit to remove the material to the collection tank, this method does create a lot more waste material for disposal due to the water volume
Extended or Drum Collection
The vacuum units reach can be extended by the use of a 205 litre drum placed between the vac unit and the suction hose, this system is useful to extend the reach of the vac unit but also to take contaminated soil straight into a drum for sample collection or to allow sealing up for disposal.
The system has been used to remove contaminated soil from around tree roots as well as to investigate existing services on sites, this is usually done by means of narrow slit trenches across full road widths and to pre clear drilling locations ahead of intrusive drilling works, as the system is safe for services exposing anything found can be done safely for positive identification
The vehicle cannot drive off site when loaded with any vacuumed spoil and must be emptied prior to leaving site