GUWAHATI, Oct 31 - The two experts engaged to re-examine the seismic coefficient, that is, peak ground acceleration (PGA), have estimated the PGA for earthquake of a maximum magnitude of 8 at the site of the Lower Subansiri Hydroelectric Power Project (LSHEP). This is contrary to the demand for considering the maximum magnitude of 8.5, which is close to the magnitudes of the 1897 and 1950 earthquakes that devastated the NE region.
The two experts � Prof Ambrish Kumar Mahajan of the Central University of Himachal Pradesh and Prof Alok Goyal of the IIT, Bombay � were selected by the Project Oversight Committee (POC) formed by the Union Government to examine the structural issues connected with the LSHEP in its seventh meeting from among the eight experts named for the purpose of re-examining the seismic coefficient or PGA of the LSHEP.
According to information available with this newspaper, at the tenth meeting of the POC, which was held on October 27, 28 and 29 in New Delhi, Prof Goyal and Prof Mahajan presented their findings before the POC members. While Prof Goyal has submitted his report at the meeting, Prof Mahajan is likely to submit his report towards the end of November, 2015.
Both the experts earlier made presentations on the methodology adopted by them to estimate the PGA value at the project site. But the efficacy of their methodology is yet to be examined by the POC experts. During their presentations on the issue, they mentioned the limitations and constraints of the models applied by them in evaluating the PGA value of the project site.
Another issue � the difference in the PGA values for the NE Indian hydel projects approved by the National Committee on Seismic Design Parameters (NCSDP) � on which the experts from Assam in the POC have been expressing grave concern, is yet to be resolved. The NCSDP has approved of a PGA value of 4.4g and above for several hydel projects proposed to be built in the NE region, while it has approved of a PGA value of .38g for the LSHEP. The Assam experts have been insisting on an explanation as to what has led to such a difference in the NCSDP approach towards the issue.
The NCSDP is a high-level inter-disciplinary official body constituted by the Ministry of Water Resources in 1991 to recommend site-specific seismic parameters for the design of dams and other pertinent structures of river valley projects.
GUWAHATI, Oct 31 - The two experts engaged to re-examine the seismic coefficient, that is, peak ground acceleration (PGA), have estimated the PGA for earthquake of a maximum magnitude of 8 at the site of the Lower Subansiri Hydroelectric Power Project (LSHEP). This is contrary to the demand for considering the maximum magnitude of 8.5, which is close to the magnitudes of the 1897 and 1950 earthquakes that devastated the NE region.
The two experts � Prof Ambrish Kumar Mahajan of the Central University of Himachal Pradesh and Prof Alok Goyal of the IIT, Bombay � were selected by the Project Oversight Committee (POC) formed by the Union Government to examine the structural issues connected with the LSHEP in its seventh meeting from among the eight experts named for the purpose of re-examining the seismic coefficient or PGA of the LSHEP.
According to information available with this newspaper, at the tenth meeting of the POC, which was held on October 27, 28 and 29 in New Delhi, Prof Goyal and Prof Mahajan presented their findings before the POC members. While Prof Goyal has submitted his report at the meeting, Prof Mahajan is likely to submit his report towards the end of November, 2015.
Both the experts earlier made presentations on the methodology adopted by them to estimate the PGA value at the project site. But the efficacy of their methodology is yet to be examined by the POC experts. During their presentations on the issue, they mentioned the limitations and constraints of the models applied by them in evaluating the PGA value of the project site.
Another issue � the difference in the PGA values for the NE Indian hydel projects approved by the National Committee on Seismic Design Parameters (NCSDP) � on which the experts from Assam in the POC have been expressing grave concern, is yet to be resolved. The NCSDP has approved of a PGA value of 4.4g and above for several hydel projects proposed to be built in the NE region, while it has approved of a PGA value of .38g for the LSHEP. The Assam experts have been insisting on an explanation as to what has led to such a difference in the NCSDP approach towards the issue.
The NCSDP is a high-level inter-disciplinary official body constituted by the Ministry of Water Resources in 1991 to recommend site-specific seismic parameters for the design of dams and other pertinent structures of river valley projects.
