Bioremediation Services in Assam and Arunachal Pradesh

Following the Baghjan well incident, Oil India Limited awarded a bioremediation mandate to restore oil-contaminated land and water bodies at Baghjan village, Tinsukia, Assam. The program applies an eco-friendly, microbe-based (bioremediation) approach developed by Oil India's R&D, with microbial cultures produced at scale by TERI's Gurugram campus and independent verification carried out through a third-party laboratory in Delhi. The contaminated area was mapped into four zones (1–4) to enable systematic treatment and monitoring.

Approach and Execution

• Site assessment: A drone survey on 6–7 July 2020 documented the affected zones, followed by zero-time (baseline) sampling of soil and water to establish initial Total Petroleum Hydrocarbon (TPH) levels.
• Site preparation: Oil-contaminated vegetation and shrubs were cleared, free oil was recovered from water bodies and consolidated on land for in-situ treatment, and the soil was tilled using tractor-mounted plough/harrow to aerate and condition it for microbial activity.
• Microbial treatment in phases: Bioremediation microbes were delivered in multiple consignments and applied in three rounds —
  • First phase across all four zones;
  • Second phase from 7–23 September 2020 in zones 1–4;
  • Third phase from 17–20 October 2020 in zones 1–4.
• Monitoring: Baseline and intermediate samples from identical sampling points were dispatched to the Delhi laboratory for TPH testing, providing an auditable record of progress.
• Visible regeneration of greenery and indigenous vegetation at the treated site after the second application.
• Pulse crops growing on the remediated land, an encouraging indicator of recovering soil health.
• A documented, phase-wise dataset (baseline vs. intermediate TPH) supporting transparent, evidence-based evaluation of progress.

The project demonstrates a scalable, low-impact remediation model that pairs Oil India's indigenous microbial technology with TERI's production and laboratory capability to restore a sensitive ecosystem — converting a contaminated incident site back toward productive, vegetated land.

Apart from the land restoration project at Baghjan village through bioremediation, TERI has successfully implemented several other crude oil-contaminated land remediation work under another bioremediation project for Oil India Limited (OIL) across Assam and Arunachal Pradesh. This project includes sites such as Shalimari (OCS-1 & OCS-2), Kumchai inside EPS and Plinth-15 (Arunachal Pradesh), NHK-486 Well No. 113, Duliajan, and several other operational locations managed by OIL.

The bioremediation work commenced on 18 October 2021, and TERI successfully completed both in-situ and ex-situ bioremediation services on 22 January 2025. The project involved the remediation of more than 42,653 m³ of crude oil-contaminated soil across multiple sites. The remediation activities were executed in four phases, each covering different volumes of contaminated soil as provided by OIL.

The project targeted a Total Petroleum Hydrocarbon (TPH) concentration of less than 5,000 mg/kg within a remediation period of 4–6 months, demonstrating the effectiveness, scalability, and industrial applicability of TERI's bioremediation technology for restoring hydrocarbon-contaminated land under diverse field conditions.