In 2013, a small group of Brazilian forestry engineers ecologists, and other scientists formed a special operations unit. Known as the Grupo de Especialização de Fiscalização (GEF), the unit operates under Brazil’s Ministry of Environment and Climate Change. GEF targets the most destructive criminal groups involved in illegal gold mining in the Amazon Rainforest. To align more closely with the ministry’s mission to protect the Brazilian Amazon, GEF could integrate environmental stewardship into its operations. Adopting measures such as protecting water sources or neutralizing heavy-metal contamination hotspots may not only foster recovery of fragile ecosystems but also signal responsibility and restraint, potentially strengthening GEF’s legitimacy and relations with local communities.

Illicit mining in the Amazon encroaches on territories inhabited by Indigenous communities like the Yanomami. It routinely releases heavy metals such as mercury into the environment, with damaging consequences to human and animal health that persist long after the miners leave. The illicit operations are oftentimes backed by syndicates and cartels, which equip the miners with camps, heavy earth-moving machinery, dredges and aircraft. They also finance supporting infrastructure, such as airstrips, to transport supplies in and smuggle gold out of the rainforest. GEF plans its operations against these illicit networks in secrecy and over several months, gathering detailed intelligence on the criminal activity. The unit’s operators undergo training developed by specialized police who combat organized crime. This training is also tailored to the rainforest environment.

The Brazilian Ministry of Environment and Climate Change presents GEF as an elite unit, emphasizing its focus on surgically precise strikes and environmental protection. Yet, despite aiming for protection and precision, GEF’s kinetic operations take an environmental toll. An account in TheNew Yorker of GEF’s approach reads:

“The team quickly found the mine pit, an ugly gouge of muddy water with a pump, a giant hose, and a sluice, along with a truck engine that served as a generator. Using cans of fuel left by the miners, they doused the machinery and lit it on fire. For good measure, one of them peppered the generator with bullets. While a few men stood guard, scanning the forest edges, others moved through the tents and a cookhouse area, searching for anything that might provide a clue to who controls the mines … Then they piled up flammable materials and set the rest of the camp ablaze.”

The flames can spread to soil and nearby trees, particularly during the dry season, contributing to further deforestation. Destruction by combustion also leaves behind toxic residues of organic matter — primarily soot, unburnt hydrocarbons, and polycyclic aromatic hydrocarbons — alongside inorganic matter that includes heavy-metal ash. In addition to environmental risks, the kinetic approach can complicate forensic investigation by destroying evidence against the illegal networks. Equally problematic, GEF raids may be perceived by nearby Indigenous or riverine communities as a show of force rather than precise strikes, potentially eroding trust in state presence and fueling resentments. Thus, while effective at rendering illicit mining sites unusable, the kinetic model can carry ecological, evidentiary and reputational costs that make its long-term effectiveness debatable.

Examples of environmental stewardship

Mining machinery can be disabled without the use of explosives. This approach targets individual machinery parts that are difficult and expensive to replace, including fuel injectors, engine control units, crankshafts and specific bearings. Similarly effective is the removal of critical structural pins, linkages or fasteners that make large machinery inoperable without complete destruction. Additionally, GEF can disrupt logistics and inflict costs on illicit mining operations by applying spill‑response technologies such as hydrocarbon solidifier powders to hydraulic lines and fuel caches. They absorb and lock diesel and gasoline into a solid form. Many of these spill‑response products come in single‑use pour‑in sachets — commonly ranging from tens to hundreds of grams — and are marketed as suitable for rapid field response. Such disablement techniques can offer several advantages: they avoid the toxic fallout and collateral damage associated with combustion, which helps to protect the surrounding environment and preserve physical evidence for prosecution and network tracing.

If a spill from the camp barrels threatens nearby waterways — and, thereby, aquatic habitats and local food sources — hydrophobic sorbent socks and booms made of peat, cellulose, organoclay or synthetic polypropylene could be used around the illegal camp. Lightweight and designed for both easy and rapid use, “boom” socks are logistically feasible for field teams. Their hydrophobic fibers absorb diesel, preventing it from spreading into nearby waterways.

In addition to such containment approaches, GEF operators can integrate ecological remediation steps into their missions. For example, they may broadcast “first-responder” tree seeds in the closing minutes of an operation. Ideal “first responders,” discussed in ecological research as phytoremediation tree species, are able to address even long-term harm inflicted by illegal gold mining — especially heavy-metal contamination. These plants not only tolerate high levels of mercury, cadmium and lead, but even absorb and stabilize them, ultimately helping to restore polluted soil. Of particular value are “hyperaccumulator species,” which concentrate particularly high levels of these metals in their tissues, facilitating the gradual detoxification of contaminated sites. Other tree species can help enrich nutrient-poor soils. Fast-growing Amazonian species establish themselves quickly, create shade, and shed leaves that decompose quickly, contributing organic matter to depleted soil.

Using “seed bombs” — which contain tree seeds mixed with natural materials like clay or biochar — or mixing the seeds with bits of moist sand, helps anchor them and retain water. They can be prepared ahead of the raid and carried in small sachets. GEF operators can scatter them manually. Seeding for a 1-hectare pit requires roughly 1–2 kilograms of seed (about 0.8-1.6 pounds per acre) — a potentially negligible weight. However, even a 10-15% germination rate can jump-start meaningful environmental recovery. Here, precision disablement of illegal mining machinery seamlessly hands off to the “precision enablement” of forest recovery — potentially without extending dwell time and increasing risk for GEF operators.

See a related video: With Brazil moving to curb illegal gold mining operations in the Amazon, tensions have risen as miners have witnessed destruction of their equipment and livelihoods:

Beneficial ecological impact

Wildlife protection is equally valuable, since different species help maintain overall ecosystem health and sustain human communities. Quieter operational approaches can meaningfully refine GEF’s profile. For example, replacing low-hover helicopter insertions — lethal to animals living in tree canopies — with a high-in, short fast-rope approach allows operators to remain above the forest canopy, reducing rotor wash and acoustic disturbance to the treetop habitats, home to numerous species, including endangered ones. Adjusting insertion timing — with input from wildlife experts and without compromising operational security — can be of particular value during peak nesting season. These periods are critical for species recovery and reproduction. Loud, low-flying aircraft can cause nest abandonment, offspring mortality and reproductive failure.

GEF could also protect local wildlife hunted for food. “Bushmeat” consumption has increased in the tropics at an unprecedented rate, and the often-unsustainable nature of this harvest has profound implications for biodiversity, ecosystem health and human livelihoods. Snares and nets — commonly used for hunting and fishing — have a disproportionately high ecological impact, because they continue to kill indiscriminately long after camps are abandoned. During GEF’s raids, a 60-second sweep through the camp and at water access points — using multitools or trauma shears — can remove bushmeat snares, tripwires and gill nets that miners have left behind. Unlike machinery or fuel stores, these traps are often overlooked in enforcement operations, despite being easy to neutralize.

GEF operations near Indigenous territories may adopt the non-kinetic framework specifically to reduce social disruption and foster more constructive relationships with local communities. In these areas, the presence of armed state agents can evoke mistrust, fear and trauma — particularly when operations involve force, fire and destruction. By shifting toward quieter, less intrusive mission profiles, GEF can mitigate these risks and signal a more respectful posture. These efforts help frame GEF not as an external enforcer, but as an actor aligned with the community’s environmental values.

GEF could also combine environmental remediation with psychological operations to undermine the confidence of illegal miners. A report in TheGuardian illustrates the mindset of these actors:

“On a recent afternoon one portly mining boss sat there, swigging beer and bragging how his team had buried its gear in the jungle to prevent troops destroying it. Miners had doused the earth over the concealed objects with petrol to help them relocate their equipment by stopping the forest from growing back.”

This anecdote exposes both the tactical thinking and the sense of impunity among illicit mining networks. By actively targeting and publicly exposing such concealment sites — especially those thought to be hidden and secure — GEF could sow doubt about the effectiveness of miners’ evasion tactics. Disseminating curated footage or imagery of discovered equipment may have a psychological impact, signaling to mining operations that GEF sees through their approaches.

GEF can target such hidden mining equipment because the petrol slick that miners spread to keep vegetation from sprouting leaves a signature. Hyperspectral sensors on drones or small aircraft can pick it up. Field studies have already mapped oil-contaminated sites in Amazonian forest, and machine-learning-based software developed for spotting clandestine airstrips could be trained to flag new vegetation voids that match the profile of buried caches. During GEF operations, portable hydrocarbon “sniffer” probes — electro-chemical or flame-ionization detectors already used by spill-response teams — can give an instant readout of volatile organics in soil and air, letting GEF trace the strongest plume to the buried stash without extensive digging. A well-trained detection canine may carry out the same task in dense understory while remaining silent.

Adding stewardship to kinetic operations

While stewardship-based operations alone are likely insufficient against organized and resilient threat networks, they are an environmentally meaningful way to complement GEF’s kinetic operations. A clear set of operational criteria can help guide the choice between these two approaches:

• First, assess the environmental sensitivity of the site: If rare or legally protected species, watercourses, or Indigenous sacred areas are at risk, non‑kinetic tactics may have priority to minimize irreversible damage.
• Second, evaluate community dependence and vulnerability: In zones where local and Indigenous livelihoods hinge on forest products or where civilians may be nearby, non-kinetic disablement and remediation reinforce legitimacy and build rapport with the communities.
• Third, consider the intelligence dividend: When details such as serial numbers, digital logs or supply-chain markers can yield follow‑on prosecutions, preserving evidence through non‑destructive means amplifies long-term impact.
• Fourth, factor in operational tempo and threat: If miners come closer to Indigenous communities or immediate public safety concerns demand rapid denial of capability, kinetic destruction provides protection and certainty.
• Finally, where feasible, apply an escalation ladder: Start with non‑kinetic disablement and remediation, then escalate to kinetic actions for repeat offenders. In this case, high-profile kinetic operations can send a powerful message to adversaries, offering short-term reassurance to communities under acute threat.

Ultimately, fighting illegal gold mining cannot rely on destruction alone. If law enforcement in the Amazon ends with wrecked machinery and scorched camps, then the forest ends there too.

Protecting the rainforest can mean transforming enforcement into a tool for healing.

Anna M. Gielas has a Ph.D. in the history of science from the University of St Andrews (U.K.) and is now working on a second doctoral dissertation.

Banner image: Brazil’s environmental agency, IBAMA, destroyed 327 miners’ camps, 18 planes, two helicopters, and dozens of ferries, boats and tractors in an operation to remove illegal miners from Yanomami Indigenous territory in 2023. Image courtesy of IBAMA.

Related audio from Mongabay’s podcast: A Mongabay Africa investigation has revealed that officials in Republic of Congo have issued several dozen gold mining permits inside a swath of forests protected by a carbon offset project (REDD+), leading to deforestation of the area, listen here:

See related coverage & commentary:

Cross-border operation cracks down on environmental crimes in the Amazon

Nearly all Brazilian gold imported by EU is likely illegal, report says

Formalizing small-scale gold mining can reduce environmental impacts & crime (commentary)

Environmental crimes are often hidden by ‘flying money’ laundering schemes (commentary)