Oil asset and production integrity

Maximum focus on asset integrity and constant oil spill monitoring.

Asset integrity

Asset integrity is central to our business. All Eni’s subsidiaries throughout the world comply with Company Standards, national legislation and applicable international standards in all their operations, and always apply serious preventive measures to contain incidents. 

Over the past years, NAOC JV facilities (wells, flowlines and pipelines approximately covering 3,000 km) have been a target of criminal groups and militants with access to the area and knowledge of the territory, engaged in illegal activities resulting in significant losses. The company has developed an integrated strategy to prevent, reduce, contain and remediate these events and their impact.

Eni’s strategy for reducing operational oil spills and oil theft involves joint action across all the possible intervention plans, from the administrative to the technical prevention aspects, control initiatives, quality and speed of intervention, and also participation in several international initiatives.

In particular, Eni experiments with, and applies, techniques that allow for the early detection of leaks, damage or effractive activities near or on oil pipelines, thereby reducing response times and related spills. In this regard, in 2018, Eni completed the installation of the e-vpms® (Eni Vibroacoustic Pipeline Monitoring System - proprietary patent) and SSPS (Safety Security Pipeline System) tools on pipelines in Nigeria.

Other initiatives to prevent and manage spills include now and for the future:

  • increased surveillance forces (Task Force) in areas most subject to sabotage; (completion of the new e-vpms technology, Clough Creek Evpms Shallow water sensor installation on early 2022 and Tebidaba is planned on 2022.
  • maintenance plans aimed at reducing the Oil Spills events.
Eni’s strategy aiming at reducing operational oil spills and oil theft has been continuously outlined through an increasingly joint action on all the possible intervention plans, from the administrative to the technical prevention aspects, control and intervention response, also through participation in several international initiatives. 

Trend of oil spill events

Compared to previous years, in 2020 we have observed a significant decrease in the number of spills due to sabotage, presumably due to the declining social tensions after the 2019 election period and an increased surveillance (around -22%). The total number cases of the 2016 Vs 2020 is decreased (around -21%). In order to achieve ZERO operational spills, NAOC JV has a robust asset integrity plans for the next years in order to progressively replace the most damages sections of pipelines.

Navigate the data about oil spills in an interactive way. Select the time span, the typology of event and facility, and gain a better understanding of this phenomenon and the impact of our preventive initiatives.

When an oil spill occurs

Following an oil spill event, NAOC JV performs a series of activities to respond, manage, contain, measure, recover and remediate. After the spill notification, verification and Containment/Recovery actions, a Joint Investigation Visit (JIV) with Government Regulatory Agencies and Communities takes place, followed by Repair, Delimitation survey of impacted area, and Clean up of impacted site. A further visit called Post Clean up Inspection (PCI) takes place with Government Regulatory Agencies and Communities, including Sampling/Analysis for close out. Remediation actions are taken if required. Final Close out Certificate is provided by Government Regulatory Agencies.

Incident data and Joint Investigation Visits

The Spill Incident data is a log for recording information on oil spill incidents, based on the Joint Investigation Visit findings. In accordance with the guidelines for sustainability reports issued by IPIECA, the Spill Incident Data table is updated on a monthly basis and contains all events registered with a quantity of oil spilled strictly above 1 barrel. Joint Investigation Visits (JIV) are conducted by teams comprises of NAOC JV, and Government Regulatory Agencies (GRA),  National Oil Spill Detection and Response Agency (NOSDRA), State Ministry of Environment (SMENV) & Community representatives. The JIV team visits the incident site to confirm the cause of spill through visual observation and Ultrasonic Thickness Measurements (UTM) to determine the quantity of oil spilled through quantitative assessment which normally includes the extension of area impacted and the thickness of oil, as well as porosity of soil (when applicable).

Clean up process

The clean-up method employed by NAOC JV for the clean up of oil impacted sites involves the following:

  • Skimming, recovery and transportation of all free-floating oil from the spill site to the nearest company crude oil facility or company approved treatment site for incineration;
  • Cutting/clearing of oil stained vegetation from the impacted area where necessary and transportation of the waste to a treatment site for incineration;
  • Scraping, gathering and transferring of all contaminated soil/oily waste to an incineration site;
  • General tidying up of the entire impacted area is carried out to the extent that there would be no oil on sediments or visible oil sheen on water;
  • After the clean-up is completed, a Post Clean-up Inspection (PCI) is carried out with Government Regulatory Agencies (GRA) where samples are collected for analysis. The site is closed-out if the results of the analysis indicates that no further remedial action is required. There is regular monitoring of the spill site by NAOC JV during the clean-up activities to ensure that the clean-up is executed in line with the scope of work and regulatory standards.

Remediation process

NAOC JV remediates contaminated sites (soil) using Remediation by Enhanced Natural Attenuation (RENA), which is an integrated use of Bioremediation and Land-farming techniques. The principle for the application of RENA is based on the fact that the hydrocarbon compounds in the spilled oil undergo biodegradation under suitable bio-physico-chemical conditions. Under RENA, various forms of activities promote these conditions, and the hydrocarbon compounds biodegrade gradually to give rise to CO2, H2O and biomass


The RENA process involves the following:

  • Site assessment: Surface visual inspection of the site, sampling (sample collection and analysis, results of analysis).
  • Site preparation:  Clearing of the site is done manually by cutting down and clearing dead logs for easy accessibility.
  • Soil preparation: Tilling and homogenization of impacted soil aimed at exposing the impacted soil to atmospheric aeration.
  • Construction of ridges: Construction of ridges in a windrows fashion to expose deeply contaminated soil to the surface for aeration and eventual attenuation through biodegradation.
  • Soil amendment:  Nutrients application to contaminated soil to enhance the biodegradation and the quality of the soil.
  • Monitoring:  The area will be monitored for a period of four months after soil amendment and samples collected and analyzed.
  • Project close out: Site to be closed out only when plants and vegetation have regenerated and the Total Petroleum Hydrocarbons (TPH) and other contaminant levels have reduced in line with the Nigerian standards.

Data Tool

Navigate the data about oil spills in an interactive way. Select the time span, the typology of event and facility to understand this phenomenon and the impact of our preventive initiatives.

Read more