Toxic fumes and leaks: Perenco’s polluting oil business in Democratic Republic of Congo

Alexis Huguet/AFP

The usually secretive oil giant Perenco decided to give the press a tour of its Congolese operations in the coastal town of Moanda last October. In his worker’s helmet and blue uniform, country director Arthur Gueriot had prepared his lines. “This is a sustainable operation,” he said.

In this far corner at the mouth of the Congo river, tankers adorned with Perenco’s logo faced the Atlantic Ocean as far as the eye could see. A few steps away on the beach, a pipeline dived into the waves towards an offshore terminal mounted by a towering gas flare lighting up the afternoon’s blue sky. The following day, Perenco’s fleet would ferry Congolese crude oil to the rest of the world, Gueriot explained. 


Alexis Huguet/AFP
Moanda, in the Democratic Republic of Congo, sits within a protected mangrove marine reserve.

As the director walked between containers and pumpjacks sucking oil from the ground, he promoted the company’s expertise in the exploitation of “mature” fields. End-of-life assets are the group’s specialty. Perenco has built its entire model on buying up unwanted aging infrastructure from oil majors in order to run it to the last drops, pocketing billions in the process. Here, in the Kongo-Central region, the multinational operates a dozen deposits bought from Chevron in the early 2000s. 

Working closely with local officials, Perenco invests “in education, access to water, electricity and infrastructure,” Gueriot said.

Despite the reassurances, accusations of environmental wrongdoing and malpractice continue to plague the company. Local associations, international NGOs, university researchers and even the Congolese Senate have pointed at repeated pollution incidents, contamination of drinking water and the increase in respiratory diseases. By compiling these different sources, Investigate Europe, Disclose and EIF identified 167 reports of pollution linked to Perenco’s activities over the last 15 years in DRC.

In a statement, the company said: “Perenco recognises that incidents relating to its activities have occurred in the past,” adding that these are “very localised minor and limited pollution incidents.” 

Flaring in the heart of the mangrove

Perenco’s extraction zone in DRC abuts a mangrove marine reserve covering 700 square kilometres of protected ecosystem. Home to tropical trees, marshes, manatees, hippos, monkeys and turtles, the reserve is defined as a “wetland of international importance”

To extract 25,000 barrels per day in this landscape of water and forests, Perenco often uses outdated and controversial methods. One example is flaring, a technique that involves burning methane released during the extraction process. This gas, which can leak in the process, is considered the main source of global warming after carbon dioxide. In 2015, the Congolese government banned flaring nationally, but NGOs have complained that these restrictions are not applied properly.

In Moanda, Perenco’s flaring is still common. For almost a decade, the group has burnt gas relentlessly, day and night. With the help of Skytruth, a US NGO which uses satellite imagery to track environmental damage, reporters involved in this investigation were able to identify at least 58 flaring sources near or within the mangrove reserve over a nine-year period. Using remote sensing software, the investigation estimates that between 2012 and 2021, Perenco released two billion cubic metres of methane into the atmosphere. In 2021 alone, the oil company had a carbon footprint equivalent to that of 21 million Congolese. It has not stopped flaring since, as a photo taken in September 2022 shows.


Environmental Investigative Forum
Ground-level flaring is a controversial technique that involves burning methane released during the extraction process.

Perenco said that its contracts predate 2015 and are therefore not subject to the ban, but that its gas management plan includes “a significant investment made to reduce flaring”. A spokesperson added that “Perenco’s activities in Moanda are compatible with the mangroves” and “contribute to their conservation.”

The Congolese government did not reply to repeated requests for comment. 

Toxic fumes and pollution

Perenco’s gas releases could also have serious health consequences. The company extracts oil from wells surrounded by a mosaic of fishing villages and scattered farms. 

A 2020 study by the University of Lubumbashi found that the Moanda region had abnormally high cases of diarrhea, respiratory diseases and benzene contamination directly attributable to oil activities. 

In 2016, toxic fumes allegedly killed a two-month-old baby and a 21-year-old man, according to residents of Kitombé, a village located at the heart of Perenco’s extraction area. In a letter sent to Renad, a local NGO, they described how the deaths happened after intense bleeding. According to Renad, local officials had written to Perenco a few months earlier to ask that the flares be made more secure in order to “save human lives” but their request remained unanswered. In Kitombé, a local farmer told EIF earlier this year that “since Perenco’s flares have come closer, palm trees no longer produce anything, just like maize and cassava fields”.



Reports of pollution allegedly caused by Perenco have multiplied over the years. Some of the most common include the burial of sludge linked to drilling. As early as 2013, the Congolese Senate denounced this practice as the waste can contain hydrocarbon residues and heavy metals. Perenco’s management of drilling fluid “does not respect environmental standards for the disposal of industrial waste, it is simply buried in a pit,” senators wrote in a report. A video shot from late last year, and sent to IE and its partners, indicates that the multinational has not put an end to this damaging practice for the soil and waterways. 

Perenco said that reports from the Senate and the University of Lumumbashi, as well as claims surrounding the 2016 Kitombé deaths, are all “false and defamatory”. The group added: “Drilling muds are treated according to international standards and pose no risk to the environment.”

Other commonly reported incidents include leaks of crude oil into the ground and surrounding streams – at least six according to our records. “We have been repeatedly alerted to cases of crude oil spilling and overflowing into fields, pastures and rivers,” said Jennifer Troncoso, director of the Congolese branch of Lawyers Without Borders. 

These damages are not unknown to Perenco’s staff. “Yes, there are leaks,” a former Perenco employee in Moanda told Investigate Europe and Disclose.

The ex-oil worker refused to go into the details of the “largest incidents” he has had to deal with. However, he said that these cases were “three quarters of the time due to human error”, and that sometimes, “a local resident would saw a pipeline to recover oil to insulate their house”. In an apparent nod to Perenco’s strategy of using aging infrastructure, he believed incidents also occurred due to “deterioration or obsolescence of the installations”.


Alexis Huguet/AFP
Workers at Perenco’s facility in DRC.

A legal challenge

The growing number of pollution reports led NGOs Sherpa and Friends of the Earth to start legal proceedings against Perenco in France in 2019. In Perenco’s defense documents, seen by IE, the group argued that the French company does not extract any hydrocarbon deposits, nor does it have any installations in DRC. Perenco France only provides support to its Congolese branches, the lawyers added.

In France’s official business register, the company even changed its corporate description in February 2020 to state that it “provides support services” to the “oil sector”. It was hitherto “hydrocarbon extraction” in “France and abroad”. But according to the former Perenco employee, environmental policies and incidents were always managed from the Paris headquarter during his time in Moanda.

In response to claims from Sherpa and Friends of the Earth, Perenco said: “The request procedure carried out by these organisations was based on unproven information.” The NGOs tried to access more of Perenco’s information in September 2019 when a judge sent a bailiff to the group’s headquarters in Paris to research documents, but he was denied access by the company. “We simply exercised our right of defence,” a spokesperson told IE and Disclose. 

A reporter in Democratic Republic of Congo contributed to this report. He is not named in the byline over concerns for his welfare.

Full responses received from Perenco can be read here.

#PerencoFiles is an ongoing investigation supported by the IJ4EU Investigation Support Scheme. The work of EIF for this story was supported by a Journalism Fund Environmental grant