Major 2026 expansion in ASGM activity in south Lombok: Gold phytomining is a possible management solution for the resulting waste

12th January, 2026

The increase in gold price during 2025 to over US$4000 an ounce has led to an apparent major increase in ASGM activity across south Lombok (Indonesia) and there are widespread reports of conflict between miners and Indonesian authorities.

At a gold price of US$4000 an ounce, ore with a relatively low gold concentration has become economically viable to process. Furthermore, there is evidence of miners re-processing old cyanide tailings. At the current high gold price, what was once tailings now becomes ore.

This increase in production is being dominated by cyanidation using tong (these are rudimentary cyanide leach tanks). Sets of four cylinders in a single operation appear to be normal.

Example of tong set up across NTB Province. Two or more leaching tanks can be found at each site, leaching gold from ore or tailings. The problem here is not the leaching, but the disposal of waste after leaching.

There are no controls in place to manage the environmental impact of the cyanide being used, or of the waste tailings after leaching. Tailings are continuing to be discharged into the landscape.

While, from Croesus Projects’ perspective, there is no evidence for extensive mercury use, there remains an unacceptable risk of mercury release into the environment as a function of the current phase of mining. We say this because the NTB rock being processed is poorly suited to amalgamation and there has been some really fantastic capacity building on alternatives to mercury use of recent years. Instead, current activities are at risk of releasing past mercury use into the environment.

Let’s explore this. Any tailings being reprocessed are likely to have been generated through earlier processing that involved mercury use, and, as such, have an elevated level of mercury. Within the tong, this mercury can be complexed by cyanide, and discharged into the environment with tailings in a soluble form. Where the tong leachate transfers soluble mercury into rice paddies, the conditions are right for methylation, generating methyl mercury which is known to accumulate in rice grains.

One location of current tong activity in south Lombok is the site of a tong 15 years ago. The highest levels of mercury ever recorded in rice grains were observed at this site in 2010. The current reprocessing of tailings and potential recycling of once stable mercury into the wider environment represents an unacceptable risk to food safety through contamination of rice crops.

Proposal for action

Croesus Projects celebrates the ASGM mining in NTB Province. However, there are things we can do.

Define regulated processing areas. The mining is not the issue. The problem is the unmanaged release of waste into the environment at the end of the mining cycle. There needs to be urgent attention to the formalisation of processing operations in areas where waste management protocols can be implemented. There needs to be a defined mining area. An appropriate area needs to be identified, and tong operations moved to this area. Enforcement needs to be enacted to legitimise the operation of processers in a defined processing area. Where processing is regulated and controlled, waste management can be enacted to mitigate the risk of pollutant release into the wider environment.

Implement environmental monitoring. The extent of food contamination across processing areas is unknown, but the current scale of operation creates significant concern about food safety. A programme of food and water testing must be enacted to safeguard the health of communities in the mining processing areas, and to the safety of food.

Manage the legacy of tailings. We know how to do this. Contain the waste, revegetate and manage the release of environmental contaminants. Croesus Projects can help here. Let’s use gold phytomining to recover the last of the gold in the tailings, creating value for the long-term closure of this problematic waste while mitigating the environmental risk of the final product of ASGM.

Uncontrolled disposal of ASGM waste into the environment. At the moment this is an environmental risk, but with gold phytomining this represents a massive community-mining based opportunity. Let's stablilise the waste and recover the last of the gold with plants.