The Hidden Peril: How Abandoned Mine Pits in South Kalimantan Became Deadly Tourist Traps

By [Your Name/Journalist]

The pristine, turquoise hue of the water at the Danau Biru (Blue Lake) in Tambak Padi Village, Banjar Regency, South Kalimantan, is deceptive. To the uninitiated visitor—lured by viral social media posts—it appears to be a tranquil, hidden paradise. Beneath the surface, however, lies a graveyard of industrial negligence. What tourists see as an aesthetic backdrop for photos or a refreshing spot for a swim is, in reality, a hazardous, abandoned Galian C (non-metallic mineral) mine pit.

The danger of these pits has once again come into sharp focus following the tragic death of a teenager, identified as ‘L’, a resident of Kertak Hanyar, who drowned at the site on June 22, 2026. His death is not an isolated incident, but a stark reminder of the mounting human cost of unchecked land exploitation in the region.

The Chronology of a Preventable Tragedy

On the afternoon of June 22, 2026, the Danau Biru was teeming with visitors. Families and teenagers lounged on the white sandy banks, while others waded through shallow waters to reach a small, man-made island about 44 meters from the shore. Unbeknownst to them, a tragedy had already unfolded nearby just hours earlier.

According to reports, the incident involving the teenager occurred around 12:00 PM local time. It was not until 3:55 PM that the Banjar Regional Disaster Management Agency (BPBD) received an official report of the disappearance. Wasis Nugraha, Head of the Banjar BPBD, noted that by the time the emergency call was placed, the victim had already been missing for four hours.

The search and rescue (SAR) operation, coordinated by the Banjarmasin Basarnas office, commenced at 5:00 PM. Arianto, the Operations Section Chief, described the recovery process. Divers were deployed to the location where the victim was last seen. Within 20 minutes, at 5:20 PM, the team recovered the body just 10 meters from the lake’s edge.

"The water was only two to three meters deep," Arianto explained. "The primary obstacle for our divers was the limited visibility caused by the muddy, unstable lake floor."

This incident has forced authorities to re-evaluate the status of the site. Despite the clear risks, Danau Biru remains a popular destination for locals seeking leisure, with little to no enforcement preventing entry.

A Pattern of Negligence: Supporting Data

The death of the teenager in Tambak Padi is part of a systemic pattern of accidents occurring in abandoned mine pits across South Kalimantan. Data provided by the Banjarmasin Search and Rescue Office reveals a grim trend: between 2023 and 2025, there were at least seven major SAR operations conducted specifically at abandoned mine sites.

The timeline of these fatalities paints a haunting picture:

• July 17, 2023: A victim fell into a former gold mine pit in the Gunung Lintang protected forest, Tanah Laut, and perished.
• September 16, 2024: A double tragedy occurred in the Hulu Sungai Selatan and Tanah Bumbu regencies, where victims were recovered dead from abandoned excavation sites.
• June 20, 2024: A drowning incident at Danau Biru Baroh, Banjarbaru, ended in a fatality.
• July 25, 2025: Two children drowned in a former mine pit in Batu Ampar, Tanah Laut.

Raden Rafiq Sepdian Fadel Wibisono, Executive Director of the South Kalimantan chapter of the Indonesian Forum for the Environment (WALHI), notes that the victim ‘L’ is the 23rd recorded fatality in such pits since 2019. "Three of these victims this year alone have been children," he stated.

As of 2024, estimates suggest that the total area of abandoned mine pits in South Kalimantan has reached approximately 53,590 hectares, comprising 814 distinct pits scattered across eight regencies. Banjar Regency alone accounts for 117 of these pits, many of which exist outside of officially sanctioned mining concessions.

The Hidden Science: Water Quality and Physical Hazards

Beyond the obvious risks of drowning, experts warn that the water in these pits is far from benign. Murjani, Head of the Association of Environmental Experts in Indonesia (Pertalindo) for South Kalimantan, conducted an independent water quality test at Danau Biru.

The results were concerning. The pH level was recorded at 5.14, indicating acidic water. According to Government Regulation (PP) No. 22 of 2021, the standard pH for lakes and similar water bodies should range between 6 and 9. "The water is acidic and does not meet the standards for human contact or consumption," Murjani explained.

Furthermore, the physical characteristics of these pits—steep, unstable slopes, unpredictable depths, and thick, silty mud—create a lethal environment for swimmers. Murjani also highlighted the "temperature trap." While surface water may be warm, the deeper, colder layers can induce shock or muscle cramps in swimmers, leading to rapid exhaustion and drowning.

"Data from the five parameters we tested provides a preliminary look, but we need deeper laboratory analysis to check for heavy metal contamination, such as iron, manganese, and lead, as well as the presence of toxic gases like hydrogen sulfide," he added.

Official Responses: A Cycle of Impunity

The response from local authorities has been criticized as reactive rather than preventative. Following the drowning of the teenager, the local police (Polsek Beruntung Baru) installed a "police line" at the site. However, it was removed shortly thereafter, with officials claiming the incident was not a criminal act.

Regarding the existence of the mining site itself, local police suggest the issue falls under the jurisdiction of the Banjarbaru Resort Police (Polres). When questioned, authorities claimed they had conducted checks on the site and found no ongoing activity. However, monitoring by WALHI and media investigators on July 14 revealed a different reality: evidence of ongoing Galian C activity, including long water suction pipes, heavy machinery, and trucks transporting materials, particularly during the evening hours.

"It is a classic case of weak law enforcement," argues Raden of WALHI. "We see illegal mining operating under the nose of authorities, yet they claim no activity is occurring. We cannot wait for more victims before taking decisive action to reclaim and secure these dangerous sites."

Environmental and Social Implications

The proliferation of these pits is not merely a public safety issue; it is a profound environmental crisis. The uncontrolled extraction of sand, quartz, and stone—common in Galian C mining—has left the landscape of South Kalimantan scarred.

Satellite imagery from Google Earth reveals that the pits in the Beruntung Baru area began appearing in 2017 and have been continuously expanded and deepened over the years. This cycle of excavation, abandonment, and eventual conversion into "tourist spots" creates a dangerous illusion of safety.

The lack of reclamation efforts by mining operators—many of whom are operating illegally—means that these pits remain open, filled with contaminated water, and accessible to the public. The socioeconomic impact is severe, as the land is rendered unusable for agriculture or forestry, and the communities surrounding these sites are left to bear the physical and emotional burden of recurring tragedies.

As long as the legal and environmental accountability for these pits remains nebulous, the Danau Biru incident will likely not be the last. The "Blue Lake" serves as a beautiful, albeit deadly, testament to the need for stricter regulation, aggressive enforcement against illegal mining, and a comprehensive program to rehabilitate the thousands of hectares of abandoned land that currently threaten the lives of the people of South Kalimantan.

"We are witnessing a slow-motion disaster," says Raden. "The pits are expanding, and the children are still playing near the edges. When will the authorities finally move beyond ‘investigations’ and take responsibility for the safety of our environment?"