Tailings dam collapse aftermath: Philex admits spills but claims these not toxic

By Thet R. Mesias

TUBA, Benguet – Metallurgists at Philex Mining Corporation said Friday spillage at the company’s Padcal Mine in this province was non-toxic to people and the environment, as the chemicals used in the processing of ore were biodegradable.

After its tailings dam collapsed Philex officials assured reassured families, farmers, and fishermen living near Padcal Mine of quick response and assistance, as part of its rehabilitation and restoration drive in areas affected by the accidental discharge of non-toxic sediment from its mine site in Benguet.

 “In actual operations, the amounts of the reagents carried with the tailings are extremely small or negligible,” they said in a six-page report prepared by Philex Mining Mill Division headed by its manager, ReynoldYabes.

“We have assisted and will continue to assist the households affected by the discharge and respond quickly to their needs, placing them among our priorities in our rehabilitation and restoration efforts following the spills at Padcal Mine,” the company’s president and COO, Eulalio Austin, Jr., said.

Already, Philex Mining has provided immediate assistance to about 45families living near Padcal Mine, as the company also engaged them in the cleanup and rehabilitation drive on Balog Creek and the area where it converges with Agno River.

Austin said that local residents have been helping the Philex team, composed mostly of employee-volunteers, in creating trails on the rugged terrain leading to Balog Creek, providing easy access for the cleaners. Also, tramlines and silt traps have been created to haul equipment and to better clean up the affected areas.

Philex Mining has said earlier that it would bring families affected by the spillage at Padcal Mine back to, if not better than, their previous status, as part of the company’s proposed Social Development Program (SDP).

“This proposed SDP shall engage the stakeholders, especially the households, for the short-, medium-, and long-term plans and programs to ensure a sustainable social and economic development,” Victor Francisco, the company’s vice-president for Environment and Community Relations, said.

 Philex Mining has also stressed its need of support and cooperation from government, the non-government sector, and the business entities concerned. This multi-party group would help shape a strategy to address the needs of the affected families and the management of Balog Creek, plus its convergence with Agno River, for the long term.

 The SDP, which is in line with Philex Mining’s commitment to social and environmental policy, would be the social aspect of the “ecosystems approach” that the company is eyeing for its cleanup and rehabilitation drive on Balog Creek, which has been affected by the accidental discharge from the Tailings Pond No. 3 of Padcal Mine.

 Philex environmental experts, and government regulators announced since the voluntary suspension of operations at  Padcal Mine on Aug. 1 that the discharge was non-toxic, and that it did not result to any injury or fatality.

 The company earlier said it was planning to implement various measures on the ecosystems approach under the program called Integrated River Basin Management, focusing on aquatic, terrestrial, and water resources management with regard to the cleanup and restoration of Balog Creek.

 Francisco said that some aspects of the short-term plan for social and economic development of the affected areas involve identifying the affected households, and putting in place the participation of other stakeholders in the process, while those in the medium plan include sustaining this partnership as well as capability-building trainings for livelihood projects.

The long-term plan, on the other hand, emphasizes, among other things, the capacity-building for maintenance of the restored ecosystem, and in preparation for making this a place where people may engage in leisure activities, such as hiking and biking, upon mine closure.

Meanwhile, the report prepared by Philex Mining Mill Division said a reagent is a substance that examines or produces other substances during a chemical reaction.

Philex Mining uses a collector or sodium isobutyl xanthate (SIBX) at concentration of 0.002 percent weight (wt.), dowfroth and/or nasfrothfrothers at 0.000535 percentwt., and the natural chemical lime at 0.0682 percent wt. as regulators of pH, which tells of the acidity level in water, in its flotation process.

Flotation is a method by which an ore’s water-repelling particles are separated from water-attracting particles by a metallurgical pretreatment process.

The report, dated Aug. 8, said that recovery of copper is estimated at 82 percent, making the final concentrations of SIBX and frother in the sediment at 0.00036 percent, or 3.6 parts per million (ppm) and 0.0000963 percent or 0.963 ppm,respectively.

It added that collector and frother go with the valuable minerals or the copper concentrate. In flotation process, the collector is used to attract the tiny particles of valuable mineral to air bubbles, which are stabilized through the use of frothers.

The sediment contains an average of 0.042 percent copper, which is a very minimal amount, making the amount of reagents present insignificant.

Lime, on the other hand, does not react with copper minerals; it automatically reacts with water in normal conditions to produce calcium carbonate (CaCO3), a compound commonly found in rocks.

The report further stated that frothers, such as dowfroth and nasfroth, are practically non-toxic to fish at minimal level (LC50>100mg/L, the standard measurement of toxicity). According to the criteria set by the European Union, these materials are not harmful to aquatic organisms. SIBX, on the other hand, is not classified as dangerous to the environment.

“The collectors and frothers are naturally hydrophobic,” the report said. “Tailings are passed through the thickeners, which use gravitational forces. There is no possibility that air bubbles will be included in the underflow of the thickener.”

Recently, the Bureau of Fisheries and Aquatic Resources (BFAR) lifted the ban on fishing at areas near San Roque Dam, in Pangasinan, after tests on tilapia and carpsamples proved that these were non-contaminated and, therefore, fit for human consumption.

Philex Mining has begun its cleanup and rehabilitation efforts in Balog Creek, through the help of employee-volunteers and households living near Padcal Mine. It has also extended immediate assistance to these families whose livelihood has been affected by the discharge of water and sediment at the company’s mine site. There have been no reports of fatality or injury as a result of the accidental discharge.