Name of the contract: Construction of Tunneling Works including Testing and Commissioning for Double Line High Speed Railway using Tunnel Boring Machine (TBM) and New Austrian Tunneling Method (NATM) for the Project for Construction of Mumbai-Ahmedabad High Speed Rail (Package No. MAHSR-C-2)
Alignment: Between Mumbai Underground Station at Bandra-Kurla Complex (MAHSR Km. 0.773) and Shilphata (MAHSR Km. 21.150) in the State of Maharashtra
Completion Period: 1280 days (3.5 Years)
Geotechnical Investigations: Static Refraction technique (SRT Survey) was used to carry out geo-technical investigation of undersea tunnel area. Final report was submitted last year.
A video related to SRT survey can be accessed here
https://www.youtube.com/watch?v=NgEmA6S0AgU&t=252s
Current status of environmental clearances in the contract affected area:
India’s apex institutes Zoological Survey of India (ZSI), Mangroves Survey of India (MSI), National Institute of Oceanography (NIO) have studied environmental impact of the project in the said area. ZSI in their report have stated that there is minimal disturbance to the wildlife in this region. There will be no mangroves being cut in this area as it will be an undersea/underground tunnel 20-40 meters below the ground/sea level.
All environment related clearances from the respective authorities i.e. Coastal Regulation Management Authority, National Board of Wildlife and Forest department are either received or authorities have principally agreed for the approval.
More information can be accessed here
https://www.nhsrcl.in/view-tender-details?tender-id=MTQ2