No harmful chemicals in Padcal fish samplesTuesday, October 2, 2012
An independent science and technology laboratory said that harmful chemicals have not been detected in fish samples taken from the waters near Philex’s Padcal Mines in Benguet province.
In a report, the Sentro sa Pagsusuri, Pagsasanay at Pangangasiwang Pang-Agham at Teknolohiya Corp. (SentroTek) said there was no detection of cadmium, lead, and arsenic in the tilapia fish it analyzed in early September.
Its method detection limit indicated in the report is 0.05 milligram per kilogram (mg/kg) for cadmium, 0.10 mg/kg for lead, and 0.005 mg/kg for arsenic.
While Philex Mining Corp. (PMC) has not used mercury in its milling operations, SentroTek said it found this element at way below the acceptable standards of toxicity in the fish samples taken from the waters near Padcal.
Metallurgists at PMC said this could be due to a number of small-scale and illegal miners who have operated in Benguet. They stressed that besides not using mercury, the company also has not applied any harmful amounts of chemicals in its operations at Padcal Mine.
Louie Sarmiento, president of the Philippine Mine Safety & Environment Association (PMSEA), has expressed confidence that PMC has adhered to its mission-vision of being a world-class and responsible mining company.
“Philex Mining has been consistent with its policy on sustainable development, for it has been creating employment and working toward progress while protecting the environment,” he said. “It has rehabilitated whatever impact its operations might have on the environment through its various social development programs like reforestation.”
PMC has repeatedly announced that the water and sediment discharge from the Tailings Pond No. 3 in Padcal are non-toxic, as the chemical compounds used in its milling operations were biodegradable.
“In actual operations, the amounts of the reagents carried with the tailings are extremely small or negligible,” the company said in a statement on Sept. 5. It explained that a reagent is a substance that, because of the reactions it creates, is used in analysis and synthesis.
The Bureau of Fisheries and Aquatic Resources (BFAR) recently lifted the ban on fishing at areas near San Roque Dam, in Pangasinan, after tests on tilapia and carp samples proved that these were not contaminated and, therefore, fit for human consumption.
PMC voluntarily suspended its Padcal operations on Aug. 1, when there was an accidental discharge of sediment from the pond following heavy rains brought about by typhoons Ferdie and Gener. There have been no reports of fatality or injury as a result of the accidental discharge, which was caused by force majeure.
Its Sept. 5 statement also stressed that it uses a collector or sodium isobutyl xanthate (SIBX) at concentration of 0.002 percent weight (wt.), dowfroth and/or nasfroth frothers at 0.000535 percent wt., 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. It said that flotation is a method by which an ore’s water-repelling particles are separated from water-attracting particles by a metallurgical pretreatment process.
In a report, dated Aug. 8, metallurgists at the PMC Mill Division 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.
The division, headed by its manager, Reynold Yabes, also said in its six-page report that collector and frother go with the valuable minerals or the copper concentrate. In a 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 report stressed that 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 sediment discharge at Padcal Mine contains an average of 0.042 percent copper, which is a very minimal amount, making the amount of reagents present insignificant.
The report further stated that frothers, such as dowfroth and nasfroth, are practically non-toxic to fish at minimal level, based on the standard measurement of toxicity. These materials, according to the criteria set by the European Union, are not harmful to aquatic organisms. SIBX, on the other hand, is not classified as dangerous to the environment.
PMC has provided immediate assistance to about 45 families living near Padcal Mine, and engaged them in the cleanup and rehabilitation drive on Balog Creek and its convergence area with Agno River.