Hand held window sampling is a technique where soil sample tubes are driven into the ground using the vibrating action of a jackhammer. The sample tubes are withdrawn using hand operated jacks to allow inspection of the soil. This type of drilling is reserved for sites with the most difficult of access, such as steep slopes and confined spaces.
Southern Ground Testing use an electrically driven jackhammer which can either be powered by mains electricity or by a generator. By running leads drilling can take place up to 100 metres from the power source.
The hand held sampling equipment is light and portable and so can be used to access the most difficult of locations, such as steep embankments or wet marshy ground. As there is no drop weight mechanism with this equipment is is not possible to obtain dynamic strength parameters. A visual inspection with hand vane testing or strength profiling using a hand held DCP is possible.
This drilling technique is optimum for drilling boreholes of up to 5 metres in depth.
Mackintosh prode testing is a light hand held dynamic probe which is used to determine the thickness and density of loose or soft soils. A five kilogram weight is dropped over 0.50m and the blows required to drive the fixed cone every successive 100mm are recorded.
Examples of the use of this equipment may be the investigation of silt lagoons or peat deposits.
Gas spiking is simply the driving of a steel point into the ground and the testing the nature of emanated gases by means of a portable gas analyser. An example of this technique might be the penetration of a landfill capping layer and the testing of released gases.