What Jambi's illegal gold mining would cost under Indonesia's own valuation rules

An investigation published by Mongabay Indonesia on July 10 documents more than 60,000 hectares of forest damaged by illegal gold mining across Jambi province, an area approaching the size of Singapore. More than 1,250 hectares of that damage sits inside Kerinci Seblat National Park itself, a 1.38 million hectare reserve that UNESCO recognised in 2004 as part of the Tropical Rainforest Heritage of Sumatra and has listed as endangered since 2011. What the reporting documents in hectares, mercury readings, and collapsed fish stocks is exactly the raw material Indonesia's own environmental law uses to calculate a rupiah figure for damage like this. Nobody has yet run that calculation for Kerinci Seblat, which is the gap this piece is really about.

What the investigation found

Mongabay's reporting traces one active mining front along Sungai Penetai, roughly 20 kilometres inside the park boundary, where forest clearing now extends more than 200 metres on both banks across a nine kilometre stretch of river. Around 30 hectares are under active excavation at any given time, worked by heavy equipment rather than the pans and small pumps that characterised illegal mining in the area a decade ago. Miners interviewed for the story described paying no rent for the land they work and answering to financiers who supply fuel, machines, and protection in exchange for a share of the gold.

Hazrun, a Depati, or traditional leader, of the Muaro Langkap Tamiai indigenous community, put the loss in terms that go beyond hectares.

"That which is being destroyed is our indigenous territory. Not just forests lost, our children's futures vanish too."

Haidir, who heads the Kerinci Seblat National Park administration, was equally direct about why years of enforcement sweeps have not stopped the advance.

"Networks are strong. Capital backers extensive. Perpetrators numerous."

A water tower for four provinces, and its biosphere condition

Kerinci Seblat spans Jambi, West Sumatra, Bengkulu, and South Sumatra, and Mongabay counts 23 river systems that originate inside the park boundary, serving an estimated five million people downstream. The condition of that biosphere is already measurable and already declining on several fronts at once. Sungai Penetai itself has turned brown and muddy where mining has reached it, and Mongabay reports that fish populations there have collapsed, ending traditional fishing for communities downstream. Separate mapping by Forest Watch Indonesia has tracked mercury, used to bind gold particles in artisanal processing, in river sediment at concentrations of 0.01 to 0.42 milligrams per kilogram, with dissolved concentrations in water fluctuating up to 0.0645 milligrams per litre against a safety threshold of 0.001 parts per million. None of that stays contained to the mining site once it enters a river system. Sukmareni Rizal, communication division coordinator at the conservation group KKI Warsi, described the scale bluntly as damage that far exceeds worrying limits and breaches conservation zones outright.

Every one of these readings, water quality, fish stock condition, forest cover, is a biosphere condition indicator, and biosphere condition indicators are precisely the inputs an ecosystem services valuation needs. That is the point at which physical damage reporting and economic valuation are supposed to meet, and in this case they have not yet.

The valuation method Indonesia already has

Indonesian environmental law does not leave the price of damage like this to guesswork. Permen LH No. 7 Tahun 2014, the environment ministry's regulation on calculating environmental loss, sets out a standard method that appointed pollution, damage, or environmental economics experts apply, splitting the total for forest-area damage into three components: ecological damage, the loss of the ecosystem's physical and biological capacity; environmental economic loss, the value of ecosystem services the land and water would otherwise keep producing, from clean water regulation to biodiversity; and recovery cost, what it would take to restore the site.

The clearest public demonstration of what that method produces at scale is the PT Timah case in Bangka Belitung, where IPB forestry economist Prof. Bambang Hero Saharjo led a team that combined satellite imagery from 2015 to 2022 with soil and forest sampling to calculate a total environmental loss of Rp271 trillion, split into Rp183.7 trillion in ecological damage, Rp75.5 trillion in environmental economic loss, and Rp11.8 trillion in recovery cost. That figure has become the reference point prosecutors and regulators reach for whenever mining damage needs a number attached to it. It has also drawn a legal challenge: a complaint filed against Saharjo argued that sampling based on satellite imagery alone is too thin a foundation for a figure that large, without enough ground verification behind it. Whichever way that dispute settles, it establishes the standard the next case will be measured against: a defensible valuation needs both the remote sensing and the ground-truthing, documented well enough to survive cross-examination.

The gap at Kerinci Seblat

No comparable exercise has been run for the Jambi case. What exists instead is a set of partial, sometimes conflicting inputs that a formal valuation would need to reconcile rather than choose between. KKI Warsi's tally at the end of 2024 put cumulative illegal gold mining land across Jambi province at 52,059 hectares, broken down by district as Sarolangun (17,362 ha), Merangin (17,320 ha), Bungo (10,101 ha), Tebo (6,819 ha), Batanghari (259 ha), and Kerinci (208 ha). Mongabay's July 2026 reporting cites a larger total of more than 60,000 hectares of damage across the province, reflecting continued expansion through 2025 and into 2026. Neither figure is wrong; they are GIS-derived snapshots from different dates and, in places, different definitions of degraded land, which is exactly the kind of baseline dataset a proper economic valuation exercise would need to standardise before it could put a rupiah number on ecological damage, environmental economic loss, and recovery cost the way the Timah case did.

That gap matters beyond bookkeeping. Flooding in September 2025 displaced 1,689 families and damaged more than 1,600 homes in Sarolangun district, destroying five suspension bridges, and a further flood in April 2026 damaged more than 250 homes in Merangin. Neither flood is attributed to mining alone, but both occurred in the districts carrying the largest mapped mining footprint, and a full environmental economic loss calculation is the tool built to separate correlation from an attributable, defensible figure.

Money, enforcement, and what is still missing

What emerges from the reporting is an organised supply chain rather than scattered opportunists. A single excavator working a claim needs one to two drums of diesel a day, and investigators trace much of that fuel back to subsidies meant for households and small fishers, diverted through informal distributors; Mongabay puts the resulting state financial loss at Rp276.5 billion. Oscar Anugrah, executive director of Walhi Jambi, argued that fuel is a more tractable target than land enforcement alone, since cutting the supply would stop machines within days even where mining sites themselves are hard to reach.

Jambi police have not been idle on the enforcement side either. Between January and June 2026, Polda Jambi opened 23 illegal mining cases, arrested 50 suspects, forwarded 13 cases to prosecutors, and seized 2,572.96 grams of gold, 10 units of heavy equipment, and Rp108 million in cash, according to figures reported by Kompas and ANTARA News Jambi in early July. Kombes Pol Taufik Nurmandia, the force's director of special criminal investigations, said police remain focused on the districts along the Batanghari River watershed where mining is concentrated. Park management has run enforcement sweeps most years since 2018 with, by Haidir's own account, limited lasting effect. What none of these enforcement actions produce, by design, is the ecological and economic loss figure that would let prosecutors, insurers, or the ministry attach a defensible cost to what has already been destroyed, the way Bangka Belitung's tin case eventually did.

Sirkularium's view

The lesson for government agencies is straightforward. Physical monitoring, satellite mapping, water sampling, biodiversity surveys, already exists in fragments across KKI Warsi, Forest Watch Indonesia, and the park authority. What is missing is the step that turns those fragments into a standardised economic valuation under Permen LH No. 7 Tahun 2014, the step that made the Timah figure usable in court and in policy debate. Commissioning that valuation now, before a crisis forces a rushed version of it, would give the ministry and prosecutors a documented, defensible basis for enforcement and compensation rather than a reconstruction under pressure years after the damage occurred.

The lesson for licensed resource operators, including those working legitimately near sensitive biospheres like Kerinci Seblat, points the other way. AMDAL approval is not a one-time hurdle; the ecosystem services baseline and biosphere condition data it requires are exactly what a company needs on file, current and independently verified through GIS mapping and ground sampling together, to demonstrate compliance if the ministry ever asks. The Timah dispute shows what happens when that documentation is assembled after the fact and under legal pressure. Operators that commission rigorous environmental economic valuation as ongoing practice, not as crisis response, are the ones positioned to defend their compliance record on the same technical terms the ministry itself now uses to calculate loss.