KOCHI: A geotechnical study should be conducted for the proposed construction of an underground laboratory in the Western Ghats, within the Idukki–Theni charnockyte aquifer, by the India-based Neutrino Observatory Collaboration, says a paper published in the latest issue of the research journal Current Science. Since there are several dams quite close to the structure and the area is prone to hydro seismicity, all safety studies should look into the impact on aquifers to ensure that the Italian story of Gran Sasso is not repeated, says the paper titled ‘Mountain tunnelling, aquifer and tectonics – a case study of Gran Sasso and its implications for the India-based Neutrino Observatory’ by lead author V T Padmanabhan, member of the European committee on radiation risk (ECRR) and Joseph Makkoli of Cochin university of science and technology (Cusat).

According to the paper, a similar observatory in Gran Sasso, Italy, built three decades ago had caused floods and severely impacted the aquifer, leading to a series of tremors and a major earthquake in 2009. The L’Aquila earthquake of April 6, 2009 caused significant changes in the hydrogeology of the fractured aquifer leading to sudden disappearance of some springs. Mid-term effects observed in the months following the main shock suggest that there was a change in groundwater hydrodynamics.

The paper says that mountain tunneling could affect the aquifer and the water bodies around the proposed site, the Idukki - Theni charnockyte aquifer (ITCA), with an area of about 4500 sq.km. This aquifer and the surface waterbodies feed three river systems – Periyar, Vaigai and Vaippar. Idukki, the water capital for six districts of Kerala and TN, has 12 dams storing five billion cubic meter of water, all within a radius of 50 km from the proposed site. To construct the lab about 800k tonne rock has to be blasted out in 800 days, using about 1,000 tonne of gelatin – all in an area less than half a square kilometre. The paper quotes an impact assessment study which said, blasting might affect the geological make-up of the locality.