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From the documents before us, it could be gathered that the Government also referred the matter to Seismic Expert, Prof. Jai Krishna who was the former President of International Academy of Earthquake Engineering and also Vice- Chancellor of the University of Roorkee. He examined the matter and opined that "the proposed dam section for the Tehri Project is safe from the point of view of seismicity of the region" and "since conservatism has entered at almost every step of decision making, the overall factor of safety of the dam is high enough to eliminate any risk from earthquake of the future." The next Expert Group that consisted of the Director General, Geological Survey of India, made a report on 25.7.1991 and recommended that the reports of the High Level Committee and the review given by Prof. Jai Krishna should be accepted. The seismic stability of the dam was further got tested through the Hydro Project Institute, Moscow, against actual acceleogram of the Gazli earthquake for the maximum vertical acceleration of 1.36g and horizontal acceleration of 0.72g both acting simultaneously and the dam design was again found to be safe. Even though the design of the dam had been earlier independently checked by two separate agencies, it was again examined and it was found that the project appears to be safe. Subsequently, during the pendency of this petition, in order to allay fears expressed in certain quarters, the Government of India in June 1996 appointed a Group of Five Experts to examine the relevant scientific and technical reports and other information relating to safety of the Tehri Dam and make its recommendations to the Government for consideration. In the selection of the experts Shri Sandra Bahuguna, who has been spearheading the movement against the construction of the Tehri Dam, was also associated and he recommended the inclusion of two engineers apart from the three seismologist. Thus the names of all the five Experts were suggested by Shri Bahuguna. The Group of Five Experts, after a detailed discussion on the various issues related to the seismic safety of the Tehri Dam, concluded that a comprehensive appraisal of the seismic safety of the dam required completion of the two key exercises by employing recent advances in conceptual and computational capabilities and they are, (i) quantitative estimation of seismic hazard at all the Tehri Dam site, and (ii) evaluation of the performance of the Tehri Dam as currently designed, if it was exposed to the estimated seismic hazard at the site. Accordingly, the Group of Experts got conducted the necessary exercises at their own decided parameters and methods. The Group also considered the International Commission on Large Dams Guidelines on Earthquake Analysis Procedure for Dams and Seismicity and Dam Design. Based on these materials the Group of Experts finally submitted the report on 18.2.1998. They concluded that the "present design of the Dam is expected to be structurally safe to withstand the maximum credible earthquake during the economic performance life of the dam-reservoir system." The Group of Experts was unanimous in their recommendation as stated above. However, as a matter of abundant caution, four Experts suggested (i) 3-D Non-Linear analysis of the Dam to evaluate its performance against the maximum credible earthquake and (ii) a simulated dam break analysis to ensure that in the unlikely event of an uncontrolled release of water, the consequences are minimum, be conducted. There was difference of opinion between the four Experts and the Fifth Expert only on the need to undertake these two additional studies as a matter of abundant caution. The Government of India, after receipt of the report of the Group of Experts, examined the further recommendation of the four out of five Experts in consultation with the Central Water Commission, which is a technical body of the Government and nodal agency in the country for planning and design of River Valley Projects who in turn referred the report of the Expert Group together with the need for carrying out the work recommended by way of abundant caution to the National Committee on Seismic Design Parameters which is a standing technical committee and it furnished its views. In addition, plethora of material has been placed by way of various text books and studies carried out by other agencies. We think that it is neither feasible nor proper for us to delve into these details. The Government of India, after considering the views thereof, finally decided that there was no necessity to undertake the work recommended further by the Four Experts by way of abundant caution and clearance to the project was given.