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 August 15, 1985 
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 Proposal for a Refinery Included in  "Assam Accord"  as a part of Government of India's offered economic package 
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 June 23, 1989 
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 IBP Co. Limited Appointed as Implementing Agency (Equity Structure IBP: 51%, Govt. of Assam: 10%, Public: 39%) 
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 May 31, 1991 
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 Environmental Clearance Obtained for Refinery Project 
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 August 28, 1992 
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 EIL Appointed as Prime Consultant 
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 July 3, 1992 
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 Foundation Stone for Refinery Laid by Prime Minister of India Shri P.V. Narasimha Rao 
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 July 15, 1992 
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 CCEA (Cabinet Committee of Economic Affairs) Approval for Implementation of Numaligarh Refinery Project 
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 April 22, 1993 
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 Numaligarh Refinery Limited Incorporated as a Company 
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 June 2, 1995 
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 BPCL Inducted as Major Promoter (Equity Structure BPCL: 32%, IBP: 19%, Govt. of Assam: 10%, Public: 39%) 
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 April, 1999 
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 Numaligarh Refinery Commissioned 
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 July 9, 1999 
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 Numaligarh Refinery Dedicated to the Nation by Prime Minister of India Shri Atal Bihari Vajpayee 
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 October, 2000 
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 Commencement of Commercial Operations 
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 March, 2001 
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 NRL Becomes Subsidiary of BPCL (Equity Structure BPCL: 61.65% ; OIL: 26% Govt. of Assam: 12.35%) 
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 October 22, 2018 
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 Public Investment Board (PIB) Clearance for Refinery Expansion from 3 MMTPA to 9 MMTPA 
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 January 16, 2019 
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 Cabinet Committee of Economic Affairs Approval for Refinery Expansion Project at a Project Cost of Rs. 22,594 Crore 
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 July 27, 2020 
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 Environmental Clearance Obtained for Refinery Expansion Project 
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 March 25, 2021 
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 BPCL Exits NRL as Major Stakeholder. OIL Acquires Majority Shares, Engineers India Limited (EIL) Enters as One of the Shareholders (Equity Structure OIL: 80.16%, Govt. of Assam: 15.47%, EIL: 4.37%) 
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 October 07, 2021 
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 MoPNG Approves Revised Refinery Expansion Project Cost of Rs. 28,026 Crore 
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 January 3, 2022 
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 Share Transfer by OIL to Govt. of Assam Complete (Equity Structure OIL: 69.63%, Govt. of Assam: 26%, EIL: 4.37%) 
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 June 22 & July 04, 2023 
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 Upgradation of NRL from Schedule-B to Schedule-A - (22.06.2023 Click here) | (04.07.2023 Click here) 
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August 01, 2024  | 
 Environmental Clearance Obtained for Poly Propylene Unit. - (Click here) 
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