Mining provides minerals used in buildings, roads, electronics, transportation and everyday products. It can also create jobs, generate government revenue and support local economies.

But mining changes the land. It can clear vegetation, remove soil and rock, build roads and facilities, and create mine waste and wastewater.

So when a mining company says it operates “responsibly,” what does that actually mean?

The basic question is whether a mine follows environmental, safety and social rules. But there is a bigger question:

Is this particular place suitable for mining in the first place?

This explainer looks at what responsible mining means, how mining including open-pit and underground methods such as block caving can affect land and communities, what happens when things go wrong, and what communities can ask before and during a mining project.

What does “responsible mining” mean in the Philippines?

There is no Philippine law called the “Responsible Mining Act.” However, the government, including the Mines and Geosciences Bureau (MGB), uses the term “responsible mining.”

Under the Philippine Mining Act of 1995, or Republic Act 7942, and related rules, mining companies are expected to operate in a technically, financially, socially, culturally and environmentally responsible way.

This includes managing environmental impacts, protecting workers and communities, and rehabilitating areas affected by mining.

But following the rules does not automatically answer whether mining is appropriate in a particular place.

That is why two questions need to be separated:

Is the mine following the rules?

and

Should mining be allowed in this particular place?

These are not always the same question.

How can mining change the land, water and communities?

Mining can affect the environment in several ways.

The World Resources Institute reports that mining destroyed more than 1.4 million hectares of forest over two decades, with nearly one-third of the loss occurring in carbon-rich tropical primary forests. Roads, railways and processing facilities can cause additional deforestation and divide habitats.

Mining can also affect water. When certain sulfide minerals are exposed to air and water, they can produce sulfuric acid, causing acid mine drainage (AMD). This drainage can contaminate water and release metals such as cadmium, lead and arsenic.

Mining also changes soil. Research has found that open-pit mining can reduce soil fertility and biological productivity. Changes in land use can also affect agricultural areas and food security.

Communities may also be exposed to dust, noise, vibrations and polluted air or water. Dust containing silica, coal or heavy metals can contribute to respiratory diseases such as silicosis and asthma. Exposure to mercury, lead or arsenic can cause neurological and developmental problems, particularly among children.

For Indigenous Peoples and rural communities, the issue can also involve ancestral land, livelihoods and cultural connections to the territory.

What is open-pit mining?

Open-pit mining, also known as opencast or open-cut mining, is a surface mining technique used to extract minerals or ore located close to the Earth’s surface.

Unlike underground mining, open-pit mining creates a large, stepped pit that expands downward and outward as ore is extracted.

The process can involve:

• Clearing vegetation and removing topsoil and overburden
• Drilling and blasting rock
• Loading ore and waste rock using heavy equipment
• Hauling ore to processing facilities
• Dumping waste rock in designated areas

Because it involves large-scale removal of soil and rock, open-pit mining can significantly change the landscape.

Vegetation and topsoil may be removed, habitats can be disrupted, and exposed soil can be more vulnerable to erosion. During rainfall, sediment can enter nearby streams and rivers.

Open pits can also alter local water systems. Exposed sulfide-bearing rock may contribute to acid mine drainage, while excavation and dewatering can affect groundwater and nearby water sources.

Continuous blasting, loading and hauling can also produce dust, noise and ground vibrations.

Example: Didipio Mine

The case illustrates why communities should examine not only whether a mining project has permits, but also the specific changes that mining may bring to the surrounding land and water systems.

What is block caving?

Block caving is a high-volume underground mining method used to extract large ore bodies located deep underground.

Unlike open-pit mining, the ore is accessed through underground tunnels. A large block of ore is undercut from below, causing the rock above to fracture and collapse under its own weight. The broken ore is then collected through drawpoints and transported for processing.

Block caving can involve risks such as:

• Surface subsidence and ground deformation
• Ground fissures or sinking in affected areas
• Air blasts caused by sudden rock collapse inside underground openings
• Mud or water inrushes
• Rockbursts caused by high stress in deep rock formations

These risks depend on the geology, mine design, water conditions and other site-specific factors.

Lepanto Consolidated Mining Company has operated copper and gold mines in Mankayan, Benguet, for decades and has used large-scale underground mining methods, including block-caving techniques.

As with other mining methods, the environmental and safety risks of underground mining must be assessed based on the particular site and operation.

Can mining increase disaster risks?

Mining does not cause typhoons or earthquakes. But mining activities can change the condition of the land.

Clearing vegetation, excavating slopes, creating open pits, constructing underground workings, building roads and storing large volumes of waste can affect drainage, erosion and slope stability.

In steep or mountainous areas, heavy rainfall can saturate soil and contribute to landslides. Sediment entering rivers can also contribute to siltation.

This does not mean every disaster near a mine was caused by mining.

A better question is:

Did a particular activity increase the risk or consequences of a natural hazard at that particular site?

That requires evidence and a site-specific assessment.

What happens to mine waste?

Mining produces different kinds of waste.

A processing mill is where ore is crushed and ground and minerals are separated using water and chemical reagents.

Mining operations may also pump water from underground areas and treat it before discharge. During heavy monsoon rains or other extreme weather, treatment and containment facilities can face additional pressure.

Waste rock consists of rock removed to access ore but not processed for valuable minerals. If waste rock contains sulfide minerals, exposure to air and rain can contribute to acid mine drainage and release metals into soil and groundwater.

What happens after mining ends?

When mining ends, rehabilitation is supposed to address disturbed land.

The Final Mine Rehabilitation and Decommissioning Fund (FMRDF) is intended to help finance rehabilitation and decommissioning.

But there can be a gap between the end of mining and the much longer period needed for environmental recovery.

Concerns include inflation, extreme weather and the possibility that problems such as acid mine drainage may continue long after mining operations have stopped.

Rehabilitation means taking actions to stabilize and repair land affected by mining. It does not necessarily mean that an ecosystem will return exactly to its original condition.

That is why communities can ask:

How long will monitoring continue, and who remains responsible if environmental problems appear years after mining ends?

What can communities learn from past mining incidents?

Past incidents show why looking only at permits and compliance is not enough.

Marcopper, Marinduque

In 1996, a drainage plug failure at the Tapian Pit of the Marcopper mine released tailings into the Boac and Makulapnit river systems.

The disaster caused serious environmental damage and affected downstream communities. The case continues to be cited in discussions about long-term environmental impacts and accountability after a mining disaster.

Philex Padcal, Benguet

In 2012, heavy rainfall caused a structural failure involving Philex Mining’s Padcal operation in Itogon, Benguet. Large volumes of silt entered Balog Creek and the Agno River system.

Philex later paid a ₱1.034-billion fine to the government to secure permission to restart operations, while advocacy groups raised concerns about long-term environmental effects and ecosystem restoration.

These cases show why communities need to ask not only:

What penalties or payments were made after an incident?

but also:

What happened to the affected environment and communities afterward?

So what should communities watch for?

A mine should not be judged by the word “responsible” alone.

Communities can ask:

Where is the mine?

Is it near a watershed, river, agricultural land, forest, protected area, steep slope or ancestral domain?

What will happen to the land?

How much vegetation and soil will be removed? How will slopes, pits, underground workings and mine waste be managed?

What will happen to the water?

How will water quality, sediment, groundwater and mine wastewater be monitored?

What are the disaster risks?

Has the project considered heavy rainfall, landslides, flooding, earthquakes and other hazards?

What happens after mining?

What is the rehabilitation plan? Who will pay for it? How long will monitoring continue?

What about Indigenous Peoples’ rights?

For Indigenous Peoples, another important question is:

Were their rights and consent respected?

The Indigenous Peoples’ Rights Act of 1997, or Republic Act 8371, recognizes the rights of Indigenous Peoples to their ancestral domains, culture, traditions and institutions.

Free, Prior and Informed Consent (FPIC) is a process through which Indigenous communities receive information about projects affecting their ancestral domains and participate in decisions through their legitimate community processes.

The legal framework also includes remedies such as the Writ of Kalikasan, which can be sought in cases involving violations or threats to the constitutional right to a balanced and healthful ecology.

What does “responsible mining” really come down to?

Responsible mining is more than having a permit or completing a checklist.

It means asking whether environmental and social risks are properly identified, whether safeguards actually work, whether disturbed land can be rehabilitated, and whether affected communities are informed and involved.

For Indigenous Peoples, it also means considering ancestral land, culture, livelihood and the right to participate in decisions about their territory.

The key difference is between formal compliance and long-term responsibility.

A mine may have permits, assessments and financial guarantees. But the real test is what happens to the land, water and communities during mining and long after operations stop.

What should we watch for next?

When assessing a mining project, look beyond the word “responsible.”

Watch for the actual evidence:

• What is changing on the ground?
• What risks have been identified?
• Are environmental monitoring results available?
• Are safeguards working?
• What happens when extreme weather occurs?
• Is rehabilitation actually being carried out?
• Who remains responsible when mining stops?
• If Indigenous Peoples are affected, was FPIC properly conducted?

The takeaway

Responsible mining is not only about whether a company follows the rules. It is also about where mining happens, what risks it creates, how those risks are managed, what happens after mining, and whether communities and Indigenous Peoples’ rights are respected.

Sources

• Mines and Geosciences Bureau (MGB) — #MineResponsibility Campaign
• Philippine Mining Act of 1995 (RA 7942) and its implementing rules
• MGB — Itogon/Ucab geohazard assessment
• MGB — Mine rehabilitation guidelines
• Republic Act 8371 — Indigenous Peoples’ Rights Act
• National Commission on Indigenous Peoples (NCIP) — FPIC requirements
• Philippine Institute for Development Studies (PIDS) — Answering Critical Questions on Mining in the Philippines
• Alyansa Tigil Mina
• Cordillera Peoples Alliance / EJAtlas — Philex Padcal Mining Disaster
• World Resources Institute — How Mining Impacts Forests
• United Nations Environment Programme — Mining and Biodiversity
• National Center for Biotechnology Information — Environmental and Health Impacts of Mining
• EJAtlas and Mongabay — Didipio mining reports
• Supreme Court of the Philippines — Writ of Kalikasan