Look Back: The 1996 Marcopper mining disaster

Gwen De La Cruz

This is AI generated summarization, which may have errors. For context, always refer to the full article.

Look Back: The 1996 Marcopper mining disaster

DISASTER. Villagers look at mine waste that overflowed from the Boac River after a damaged tunnel of the Marcopper Mining Corporation discharged tons of copper mine tailings polluting the Boac River

AFP photo

(UPDATED) On March 24, 1996, the Philippines saw one of the biggest mining disasters in Philippine history, which led to a drastic change in the country's mining policy

MANILA, Philippines (UPDATED) – It was 21 years ago today when the Philippines saw one of the biggest mining disasters in the country.

On March 24, 1996, the drainage tunnels of Marcopper Mining Corporation’s open pit ruptured and spilled millions of tons of mine waste that smothered the Boac River in Marinduque, inundating villages and killing marine life.

Let’s review the disaster that drastically changed the country’s mining policy.

Act of nature?

Marcopper Mining Corporation, which was then co-owned by Canadian firm Placer Dome, started its copper mining operations in Marinduque island in the late 60s.

Antonio La Viña, Environment undersecretary at the time of the disaster, said the company had already been dumping mine tailings into bodies of water.

This became an issue with residents, as they were seeing the damage it brought to their area.

Despite this, the Department of Environment and Natural Resources (DENR) renewed the company’s mining permit, on condition that Marcopper stops throwing mine tailings into the river.

To comply with the government’s requirement, Marcopper used one of their old open pit mines as their dam, where they could keep all their mine tailings.

Since the open pit was used in previous mining operations, they sealed all tunnels connecting to the river using cement. La Viña clarified that the tunnels were created to “bring water to the [mining pit],” and not to throw waste.

He said that it was a “fundamental design mistake” which can be attributed to lower spending. “Kasi problema palagi yung ayaw nilang gumastos (It’s always a problem that they don’t want to spend),” La Viña said.

As time passed by, the dam was being filled with mine tailings. This brought pressure to the tunnel, causing seepage of the mine waste. La Viña said Marcopper was aware of the leaks, and they had been trying to figure out what to do with them.

Then, a minor earthquake happened. A week after, the tunnel was ruptured.

Marcopper blamed the earthquake for the damage, saying that the rupture was caused by an “act of nature.”


The incident saw 2 to 3 million tons of mine waste spilling into the Boac River.

It caused flash floods that buried villages. About a third or 20 out of 60 villages had to be evacuated with approximately 20,000 people affected.

As the agricultural and marine life got severely affected, the government declared Boac River dead. Nearby villages lost one of their major sources of livelihood.

Despite glaring damages and reports of sickness, Marcopper claimed that the spills were non-toxic.

Eventually, the company closed and the mining operations stopped.

‘Criminal negligence’

WASTE LAND. Photo shows an aerial view of the dredge channel in the Boac river estuary where mine tailings from Marcopper spilled into the sea in 1996. Photo from Newsbreak/ Marcopper Mine Post-Spill Impact Assessment December 2001 report

La Viña, who is an environmentalist, told Rappler that he was tasked by then environment secretary Victor Ramos to lead the investigation and recommend immediate measures to address the effects of the disaster.

“We found out that they were negligent,” La Viña said. His team found the president and the managers guilty of “criminal negligence.”

Prior to the disaster, mining companies had a good relationship with government, La Viña said.

“The government and the mining companies were always seen in solidarity with each other. They didn’t blame each other. The government [usually] takes the fall,” La Viña explained.

This time, however, it was different as it was “the first time ever that the Philippine government had a different version from the mining company,” he added.

While Marcopper remained firm on their stand that it was an act of nature, the government believed that it was indeed their fault.

Kasi bakit ninyo ginawang ganyan yung tunnel? At kahit na nagsimula nang mag-leak bakit hindi kayo [nagkaroon] ng sense of urgency (Why did you construct the tunnel that way? And when it started leaking, why didn’t you have a sense of urgency)?” La Viña asked.

Mining sites are supposed to be earthquake- and flood-proof, La Viña said. They found out that Marcopper did not spend enough money to make sure their mining site complied.

The indictment of two officials from Marcopper, as well as the intense scrutiny of the international community pressured Placer Dome, according to a 2002 case study published on Mining Watch Canada.

Weeks after the disaster, then Placer Dome CEO John Willson wrote to President Ramos committing the company to help those who were affected by the disaster.

“The residents of Marinduque who have suffered personal inconvenience or damage to their property as a result of the Marcopper event will be quickly and fairly compensated,” Willson was quoted as saying.


While the mining company eventually recognized its responsibility to help those affected, La Viña did not mince words when asked if the government had its own shortcomings as well. (READ: Dirty Past)

“Yes. Why did you approve a mining (operation) like that? It was so risky. Why did you approve the tunnel? We did approve the tunnel also, but the defense of our staff was, they thought they would plug completely,” he explained.

Monitoring of the mine at the time, could have also been increased. The budget of the government, however, was not enough, according to La Viña.

With the friendly relationship that the mining companies and the government had, the latter became complacent, he added.

“That’s why separation is important. That signaled to the industry that from now on, if something happens, we’re not allies,” La Viña said.

Impact on policies

TO DUST. Trees in a critical watershed are cut down to make way for a mining operation in Mindanao. File photo by Pia Ranada/Rappler

The Marcopper mining disaster made a huge impact on the mining policies of the government.

For one, the Philippine Mining Act, which was enacted a year before the disaster, had to be stricter, contrary to its initial goal of liberalizing the mining industry in the country. (READ: TIMELINE: Philippine mining laws and policies)

“So can you imagine, we were ready. Hundreds of companies came here. And then Marcopper happens, and I come in with the instructions of President Fidel Ramos – be strict with mining,” La Viña said.

Since the disaster, there was an increase in concerns regarding mining, prompting the government to revise rules of the Mining Act to focus more on the protection of the environment and address social issues surrounding it.

“During our time, we were not able to approve any single one because the mining companies were still adjusting. We were very strict,” La Viña said.

The stricter mining policies focused on setting standards that were at par with other countries like Australia.

They also made sure that after the disaster, there would be higher standards for rehabilitation, and stronger provisions on no-go areas. Mining companies now have to prove that they have enough money to deal with possible hazards. Consultations with the local government and indigenous people who may be affected were also deemed important.

Two decades after

WRIT OF KALIKASAN. Before nickel mining started in 2007, around 2000 hectares of farmland could be irrigated, and this year it is down to 800 hectares. Photo by Randy Datu

The Philippines is the 5th most mineral-rich country in the world for gold, nickel, copper, and chromite, but its vulnerability to natural disasters that can adversely affect mining operations should now also be considered. (READ: 9 things you need to know about mining in Philippines)

More than two decades after the disaster, there had been at least 5 more mining disasters, one of which was the Padcal incident in Benguet involving Philex Mining Corporation, considered the “biggest mining disaster in the Philippines” in terms of volume. (READ: #WhyMining Conversation: Which is worse, Philex or Marcopper incident?)

In 2012, one of its tailings ponds had a series of leakages due to heavy rains from the onslaught of Tropical Typhoons Ferdie (Vicente) and Gener (Saola).

Meanwhile, the affected villages still suffer from the effects of the Marcopper mining disaster. In 2016, the provincial government of Marinduque planned to pursue a mutli-billion-dollar suit against the companies involved that was initially rejected by the Nevada State Supreme Court in the US, an Inquirer report said.

For La Viña, the safety of Filipinos should not be compromised for the sake of getting benefits – jobs, government revenue, development or investments – from the mining industry. (READ: IN NUMBERS: Economic promise of mining in PH)

In a 2015 statement released by Ibon Foundation, it is said that large-scale mining, like Marcopper, have little, if not none, contribution to the economy.

“Some 98% of Philippine mineral production is exported for use by other countries’ steel industries while the country has none despite its being one of the world’s top producers of gold, copper and nickel,” the statement said.

“If the risks are great, you should not allow mining. If the risks are less than the benefits, then you can allow mining – but make sure that mining companies set aside money to pay for the risks,” La Viña explained. – Rappler.com

Add a comment

Sort by

There are no comments yet. Add your comment to start the conversation.

Summarize this article with AI

How does this make you feel?

Download the Rappler App!