There’s structure beneath: Survey firm

Labouring through the better half of January this year, the company used state-of-the-art Ground Penetrating Radars for underground mapping of the site. The radar sends out electro-magnetic waves to study soil layers. The data provided by the radars is capable of distinguishing between large boulders, rocks and structures buried underground.

For nearly 20 days, a 10-member team, including Canadian geologist Claude Robillard, used the radars to study the site. Another 25 days were spent in interpreting the exhaustive data collected by a field team of three experts and 10 helpers.

The technology used by the company to conduct the study — introduced by them six years ago — has an accuracy of five per cent for positioning and 10 per cent for depth. The findings at the disputed site were well within these parameters, company sources said.

Surveying the nearly 4000 sq ft site, as per directions of the ASI, cost the company approximately Rs 25 lakh, the sources said. In fact, the same technology was used for a similar study, conducted on behalf of Delhi Metro Rail project, on the stretch between Delhi University and Central Secretariat.