The large ravine running through the city of Neuquén, in north-western Patagonia, separates its two realities. The neat, suburban streets in the valley below are much like any other Argentine city. But up in the plateau, there is immediate evidence of the country’s industrialisation. Power lines criss-cross a sea of empty housing plots awaiting new residents in one of the fastest-growing regions in the country.
Driving these changes is Vaca Muerta, one of the world’s largest shale oil and gas deposits and a formation hailed across Argentina’s political spectrum as the country’s economic salvation.
According to data from the Neuquén Ministry of Energy, more than 97% of the province’s oil and over 90% of its gas are extracted through fracking – a technique that involves injecting water, sand and chemicals at high pressure to fracture the rock and release hydrocarbons. In late-2025, Argentina’s all-time daily oil production record was broken, boosted by production increases in Vaca Muerta.
Fracking is a controversial technique that has been linked to increased earthquakes. But residents point to another hidden side of the boom: waste. Experts argue that waste from fracking is not being properly treated in Argentina, leading to environmental contamination and potential risks to public health.
Local rules require it to be properly processed. But mountains of waste serve as evidence to the contrary.
Life under the waste mountains
Quality of life in Neuquén depends on the direction of the wind.
“When it blows this way, the smell gets really strong. It stings your eyes and makes you sneeze constantly,” says Julio Polo. He is a security guard at an urban development surrounding the Neuquén West Industrial Park (PINO), where some companies have treated and stored fracking waste.
The smell is like sulphur, although there are many more chemicals in the air and soil.
Fracking generates two types of waste. Contaminated water returns to the surface after fracturing, along with naturally occurring brine, and is injected into underground disposal wells. This practice has been linked to induced seismicity as the pressure can reactivate dormant faults. In some North American countries, up to 70% of this wastewater is reused for fracking and other industrial purposes, but in Argentina, over 95% is disposed of underground, Pedro Brisio, a member of the board of directors of the Neuquén Association of Environmental Professionals, told Vaca Muerta News.
The solid waste from fracking, meanwhile, is a damp, earth-coloured paste composed of drilled rock, called cuttings, mixed with processed waste and sand. Over several years in Vaca Muerta, subcontractors have piled up this sludge to form visible mountains, some very close to residential areas.
Provincial regulations require this sludge to be processed in approved ways, including via high-temperature furnaces that burn off toxic components, reducing it to ash. But in practice, treatment capacity has consistently fallen short of the volumes being produced. Waste is piling up. In 2023, volumes increased by more than a third compared to the previous year, according to data accessed by journalism NGO Chequeado.
International investors have a significant stake in the boom driving this waste. Chinese companies have invested roughly USD 6 billion into Argentina’s fossil fuel sector, including Vaca Muerta, according to analysis by news outlet Perfil. This represents around a quarter of all Chinese investments in the country.
Pan American Energy, the fourth-largest oil producer in Vaca Muerta, is one such investment, jointly owned by Bridas Corporation and BP. Bridas is a joint venture between the Argentine Bulgheroni family and China’s state-owned offshore energy giant CNOOC, whose stake in Bridas made up half of China’s total fossil fuel investment in Argentina.
As Argentina races to become a major liquefied natural gas (LNG) exporter, China figures among the key potential buyers the Argentinian state-owned energy company YPF is targeting, alongside Brazil, India, Japan and Europe.
Fracking and its waste are significant sources of pollution for nearby areas. According to a 2019 study by the Concerned Health Professionals of New York initiative, more than 200 pollutants were documented in the air near fracking operations in the US, and more than 1,000 chemicals were found in fracking fluids. The study also describes radioactivity in residual water.
In Neuquén province, there are five secure landfill sites and five treatment plants currently in operation, according to Leticia Esteves, Neuquén’s minister for tourism, environment and natural resources. There are also three treatment plants that have been or are currently involved in legal disputes related to pollution cases: E.ET., HP&V and Comarsa.
Esteves said no new landfills will be authorised. “Companies need to invest in alternative waste treatment methods, not only for environmental reasons, but also for logistical reasons,” she added.
She emphasised that the existing sites are safe and properly licenced, but acknowledged that they are “sacrifice zones”: “They will never be able to be used for anything else again.”
The Comarsa case
One company being accused of polluting the area is the Sanitation and Materials Recovery Company (Comarsa), which has operated within the PINO since 2009.
The prosecution in the case accuses it of accepting far more material than it was capable of treating in its four furnaces.
The result, the prosecution told Dialogue Earth, was around 350,000 cubic metres of waste piled in the open air on unsealed ground, overflowing from the site’s concrete containment walls.
In 2024, Comarsa lost its state licence to process drilling waste, including cuttings. Its furnaces were dismantled, and the company was ordered to transport the waste to a designated site around 115 kilometres away, in an area removed from urban environments, Esteves and the prosecution said. Rafael Colombo, a lawyer who is part of the case against Comarsa, alleges that the accumulation of waste has caused soil and air pollution, including elements which can be harmful to human health like benzene, lead and arsenic.
In the most recent court hearing in March, lawyers representing Comarsa sought to downplay the environmental damage, according to records accessed by Dialogue Earth. They said the company was already removing the waste from the site in Neuquén and that this would be completed soon. They also said the soil surrounding the plant wasn’t contaminated.
The people living in these informal settlements are young families. The vulnerable group [suffering from the pollution’s effects] is mainly kidsDaniel, a teacher in Neuquén
The original furnaces, which have now been closed, have taken their toll on the area’s residents. Several who spoke to Dialogue Earth describe similar experiences: strong odours causing irritation to the mouth, nose, and eyes, difficulty breathing, and headaches. They all attribute this to the Comarsa plant. Several of the plant’s neighbours claim these symptoms return in hot weather or after rain.
Carlos, who preferred not to reveal his surname, has lived there all his life and recalls that when the furnaces were in operation, the symptoms were much more severe. “The furnaces burned inefficiently. They emitted black smoke. At night, the smoke is less visible, which is why they often burned more at night,” he claimed, echoing the views of four other residents.
Daniel, a teacher who protested the plant in 2016 who also declined to provide his surname, said that the smoke provoked health issues. “That was when babies and children began to suffer the effects of the pollution,” he claimed. “Just imagine, the people living in these informal settlements are young families. The vulnerable group is mainly kids.”
Comarsa’s legal team did not respond to Dialogue Earth’s request for comment. The case is awaiting trial.
At this year’s legislative opening, an annual address in which political leaders outline their achievements and priorities, Governor Rolando Figueroa announced that 139,000 tonnes of waste had already been removed from Comarsa’s plant in Neuquén.
The landfills of Añelo
Neuquén is not the only town transformed by fracking. Añelo lies just over 100 kilometres away, beside a road that offers direct access to the Vaca Muerta gas field. A constant stream of white vans and heavy goods vehicles rumble down the thoroughfare.
Añelo wasn’t always like this. “It had around 1,000 inhabitants. It started as a post office that later became a village of livestock farmers, mainly goat farmers. That changed just over 15 years ago,” says Cecilia Romero, a teacher and resident. “From goat barbecues and traditional rural festivals where everyone wore espadrilles, berets, and rode horses, we’ve gone to a line of lorries all day long.” She estimates that around 50,000 people now pass through Añelo every day.
As in the regional capital, Añelo has a plateau where the population arriving to work in the industry settles. Despite lying beside one of the world’s largest gas fields, these neighbourhoods only had gas installed a few months ago, some residents told Dialogue Earth. And they are less than two kilometres from one of the landfills where solid waste from fracking in Vaca Muerta are processed.
In this facility is a plant operated by Indarsa, a company controlled by the Urcera Group, one of the province’s most important business groups. It controls two of the five landfills in the area, according to records from the NGO Center for Research and Prevention of Economic Crime (CIPCE), accessed by Dialogue Earth.
When Dialogue Earth visited the area, mountains of sludge as tall as a five-storey building were seen at the largest of these sites. The sludge is processed into ash, which is then deposited there. Water was seen being sprayed on the mounds to prevent the strong Patagonian winds from blowing dust across the local neighbourhoods, but this is not always successful.
Sludge transported from Comarsa’s facility in Neuquén also ends up at this site.
Some residents are concerned about the impact of this waste on water supplies. “We drink bottled water because we know the river water isn’t good. It might be contaminated with oil chemicals,” says one local.
Indarsa has not responded to a request for comment.
However, waste was not the main concern for most Añelo residents. They do not see Vaca Muerta as bringing development or jobs for them. “We’re fighting against outsiders, trained for the oil industry. We are people from Neuquén who grew up in the valley with cattle and goats,” reflects one resident. “So you have to adapt to a situation that has been imposed on you.”
Esteves acknowledges that there is pressure to resolve the problem of solid waste from fracking as soon as possible. Oil companies will soon be required to treat their waste with more modern methods, she said. The intention is for this to be done at the extraction site itself. State oil company YPF is already in the process of developing a waste treatment plant 17 kilometres from Añelo.
For Esteves, the US is an example of the opportunities being missed in Argentina. “Over there, they are discussing using the ash in the construction of roads and motorways,” she said.
Meanwhile, in Argentina, production is growing, and the mountains of waste continue to pile up.
