The oil refinery that once stood on the bank of the Tigre River is long gone, but the site in Peru’s northern Amazon region has yet to be fully reclaimed by the surrounding tropical forest. At the chanchería, or pig sty—so called because devices called “pigs” used to be inserted into oil pipelines there to clean the conduits and check for damage—a real sow and her piglets root around for food.

A nearby lake where local Kichwa people used to fish is stagnant with algae now. Meanwhile, a stream that ranks among the Peruvian Amazon’s most contaminated oil-production sites—known as Gringoyacu, a reference to the foreigners who operated the refinery—empties into the nearby Tigre River. “In 1977, there was an oil spill here and it filled the river,” says Maguén Magipo, the apu, or president, of the native community of Marsella.

He swings his machete at thick grass that he says is among the only vegetation that can flourish on the contaminated soil. The blade of the tool clangs against the ground, which has the consistency of asphalt. Nearby lies a corroded chemical barrel, half-buried in dirt and leaf litter.

“There used to be lakes, there used to be fish,” Magipo adds. “Our ancestors hunted here. When the company [U.S.-based Occidental Petroleum] arrived, this place became a dump.”

The former refinery grounds are on a list of 32 contaminated sites that the Peruvian government has pledged to clean up in the country’s northern Amazon region. A day after Magipo guided visiting journalists around the abandoned plant, specialists arrived to take water and soil samples as a first step toward drafting an environmental-remediation plan.

The cleanup planning follows more than four decades of largely unregulated pollution in the oil field formally called 1AB and now known as Block 192. The oil-concession area overlaps the Pastaza, Corrientes and Tigre rivers in a remote area of Peru near the Ecuadorian border that is home to Quechua, Achuar and Kichwa people.

Contractors visited the 32 sites in February, when water levels were high, and again in September, during the dry season. Initial remediation plans, to be submitted by the end of the year, are expected to be revised and finalized in early 2019.

This is the closest Peru has gotten to cleaning up Block 192, where oil production dates from the 1970s, and where indigenous groups have been battling for a cleaner environment for nearly two decades. The area is crisscrossed by ageing, sometimes leaky conduits that move oil from still-operating wells to a large pipeline that is connected to a refinery and port facilities on the Pacific coast.

Whether or not the remediation actually will occur is very much an open question, experts say. A key reason is cost. An initial US$15 million government fund for environmental cleanup is nearly exhausted, and future budget allocations are uncertain. There’s also the problem of scale. Depending on how oil-contaminated sites are counted, there could be as many as 2,000 specific locations requiring cleanup in Block 192.

Remediation of 92 sites that have been identified on one government cleanup list could require as much as US$300 million. So says an independent assessment of the environmental impacts of oil production in Block 192, a study that was funded by the Peruvian Ministry of Energy and Mines and coordinated by the U.N. Development Programme (UNDP).

That assessment, completed in June and made public in August, points to environmental impacts and health hazards resulting from years of poorly regulated oil operations. It also cites loopholes and contradictions in government environmental regulations that apply to the oil and gas industry.

Block 192 was operated by Occidental Petroleum from 1971 through 2000, and by Argentina-based Pluspetrol from 2001 to 2015. Canadian-based Pacific Stratus then signed a two-year contract that was extended until 2019 because the pipeline operated by state-owned Petroperú, which pumps crude to the Pacific coast from concession areas including Block 192, was shut down for repairs after a series of spills. (See "Petroperú chief departs after northern pipeline leaks again" —EcoAméricas, July 2016.)

For nearly four decades, produced water—the hot, salty, heavy-metals-laden water that emerges from oil wells along with crude—was discharged, untreated, into rivers and streams, which were the only source of water for drinking, cooking, washing and bathing for villagers along the Tigre River. Residents recall the water tasting of salt and a white crust forming on their skin after they bathed.

Contamination that the disposal of produced water caused in the sediment of rivers and streams has been aggravated by more recent oil spills from the network of pipelines connecting wells and storage tanks. The result is chronic exposure of fish and other aquatic organisms to heavy metals, hydrocarbons and salts, according to the assessment coordinated by the UNDP.

The study, based on assessments of 72 locations in 24 tributary watersheds along the Pastaza, Corrientes and Tigre rivers, found that sites supposedly remediated by Pluspetrol before it abandoned Block 192 had not been cleaned up properly. It also stated that sometimes the remediation methods used had worsened the contamination.

Specific problems cited in the study included Peru’s lack of official environmental standards for sediments. The study also pointed to loopholes and inconsistencies in Peruvian legislation—for instance, the absence of a clear definition of environmental remediation in the wake of pollution from oil and gas projects.

The UNDP team recommended that in order to set future cleanup priorities, human-health and ecosystem risks should be evaluated and relationships between sites must be examined.

Site assessments must evaluate the type of pollutant, whether or not it is weathered, and the degree to which humans and fauna are exposed to it, says Margarita Núñez, a Spanish biologist who led the UNDP study team.

“There’s no point in starting to remediate places where there is no risk” because remediation is expensive, says Núñez, a specialist in aquatic ecology who works as an independent consultant in Costa Rica. “Our proposal is to look at the hazardous sites and conduct a risk assessment. That will tell you where you have to make the greatest investment.”

There is still much to learn about how pollutants are dispersed in Amazonian ecosystems, but the need for further study should not stand in the way of an immediate start to the cleanup, she says.

Although Peru began enacting environmental legislation for the oil and gas industry in the 1990s, the requirement that produced water be pumped back underground did not apply to existing oil operations. Oil fields where operations were underway, like the one that is still being exploited in Block 192, could continue to discharge produced water directly into the local environment.

It took a protest by Achuar villagers, who seized Pluspetrol’s installations on the Corrientes River in 2006, to force the company to agree to comply with the new regulations even though it had been grandfathered out. Work to do just that was completed in 2015, but some of the so-called reinjection wells into which the produced water has been pumped appear to be leaking salty water into the environment, indigenous groups say.

One place where produced water appears to be escaping from a reinjection well is about an hour from the native community of 12 de Octubre, along a dirt road that turns boggy and slick in heavy rains. Segundo Cariajano, the community’s apu, steps onto an elevated pipe carrying hot oil across what used to be a lake. Sediment has accumulated over a layer of oil several meters deep in the lakebed, he says.

Guillermo Venancio, the village’s environmental monitor, thrusts a pole into the ground and oil oozes to the surface. Not far away, in forest near an oil well, firm ground gives way to spongy soil where crude dumped during drilling has weathered and accumulated a cap of soil and leaves.

Similar sites are scattered through the forest, and about 15 houses in the village are built on land where oil drums once were stored. Little grows in their gardens, and an oily odor emanates from the ground as the sun heats the soil.

Much of Block 192 is dotted with contaminated sites, some of which pose a greater threat than others. The weathered petroleum in the forest poses less of a hazard than new spills or places where rain-driven flooding causes heavy metals to travel downstream or wash into the forest, Núñez says.

Environmental monitors like Venancio are organized by indigenous federations and supported by nonprofit groups. They have helped locate and map many polluted sites in Block 192. Familiar with local terrain, trained by the nonprofits in GPS use and even instructed in how to do basic fish biopsies, indigenous monitors have played a crucial part in revealing the true extent of the pollution.

Indigenous federations in the Tigre, Corrientes and Pastaza watersheds have been fighting for cleanup since the early 2000s, winning incremental victories through protests and negotiations. A government commitment to address health problems led to a toxicological study of villagers along those three rivers, as well as the Marañón River, into which they flow.

The Marañón is a major tributary of the Amazon. Preliminary results showed varying levels of lead, cadmium, mercury, arsenic and other metals in people living along the rivers.

Talks about addressing environmental-health risks and improving basic services also led to the installation of temporary water-treatment plants in more than 60 villages. Subsequent monitoring showed a decrease in diarrheal illnesses, especially in children, in communities where the water-treatment plants were installed. Many communities downstream of polluted sites still do not have safe water sources, however. The government proposed rainwater-capture systems, but indigenous leaders objected, saying the systems are poorly designed and built.

Though the UNDP assessment and the initial site studies appear to have set the stage for action, there are ongoing questions about the government’s commitment to make sufficient funds available for a thoroughgoing cleanup.

Minister’s pledge

In mid-September, Francisco Ísmodes, Peru’s energy and mines minister, told foreign journalists that the government was committed to remediating contamination from oil and mining pollution in the country. He said his ministry was requesting nearly US$50 million in its 2019 budget for the work in Block 192 and would seek support from international-cooperation agencies, although no specific steps in that direction have been taken.

Block 192’s fate after the current contract with Frontera Energy expires in 2019 is also unclear. Petroperú, the state-run oil company, plans to operate the field with an outside partner, according to James Atkins, chairman of the company’s board of directors.

In 2015, however, companies that had initially expressed interest in the block withdrew from the bidding, and Pacific Stratus, which later became Frontera Energy, took over the concession with no commitment that it would invest in exploration.

Indigenous federations demanded that the government conduct a prior consultation process before signing a new contract for the block in 2019. The last consultation, in 2015, was marred by divisions within indigenous organizations. Several of the groups that began the process refused to sign the final agreements, arguing that the government allowed splinter groups to join the consultation after it was underway.

The Ministry of Energy and Mines had opposed a new consultation, but Perupetro, the state agency responsible for oil and gas contracts, has agreed to begin “citizen participation,” which involves informative workshops for communities, and a prior consultation with indigenous communities, which is a four-month dialogue process regulated by law. That process is scheduled to begin by the end of this year.