A GROUND investigation company has unveiled a state-of-the-art miniature drill worth more than £100,000.

Windermere-based Geoinvestigate's unique microdrilling rig can rapidly locate holes in the ground, caves, mine workings or sinkholes in confined or sensitive building spaces, residential areas or inner cities.

Specially engineered by experts from across the world over three years, its design is said to 'represent a major improvement over existing systems'.

Ross Nicolson, managing director for Geoinvestigate, which explores sites for new building projects, house extensions, building subsidence and contamination, said: "The drilling of boreholes remains the only conclusive way of proving that there are no mine workings or sink holes beneath a site. "The new rig currently offers by far the safest way to drill mine workings where there may be a risk of mine gas explosion, igniting coal fires or releasing toxic or suffocating gases which may rise to the surface and seep into buildings and houses."

Its speed allows the company to drill a large number of holes in the footprint of new buildings to locate sinkholes that may be lurking hidden below the soil cover.

Another advantage is its quietness while it produces less drill waste.

Cumbria has a rich history of mining with major ironstone deposits, underground workings and mine shafts occurring around Ulverston, Eskdale and Millom, with numerous smaller deposits at Langdale, Coniston and Grasmere.

"Sinkhole depressions or shake holes as they are known locally can be seen in many farm fields around the margins of Cumbria from Town End to Crosthwaite and in the Western Dales in the vicinity of Kirkby Lonsdale and Ingleton," added Mr Nicholson. "Several years ago Geoinvestigate were involved when a number of sinkholes opened-up under the tennis courts at Queen Elizabeth School, Kirkby Lonsdale, and under the schools chemistry block. Concrete was pumped into the holes to stabilise them."

Mr Nicholson believes new development in the region in areas underlain by limestone should have a sinkhole survey conducted before construction starts.

Office manager Stuart Howe said: "The undoubted success of microdrill means we're going to be taking on more staff in the near future and we may need to order a second or even a third microdrill very shortly to deal with our increasing workload.

"We expect to pick-up a lot of work with the new machine not only in the traditional coal mining areas of the North West but also in the South of England where sinkholes are a big and increasing problem."