In a statement, Environment Secretary Ramon Paje said the suspension order that was issued on Aug. 2 remained in effect as of Saturday, and will stay until the safety of the company’s tailings pond has been assured.
The accidental discharge of water and mine wastes from Philex’s tailings pond No. 3 was stopped Friday afternoon, officials said.
Philex has three tailings pond but only tailings pond No. 3 is actively used, Mines and Geosciences Bureau Director Leo Jasareno said. The two other ponds have been decommissioned and rehabilitated as forest areas.
Ocular inspection by the MGB and the Environmental Management Bureau on Friday found that the San Roque Power Dam has not been affected by the discharge. Laboratory analysis of water samples, however, was continuing.
The dam is situated at about 30 kilometers downstream of Agno River from its confluence with Balog River. The drain tunnels discharge their water load into the Balog River, which runs for about 2.5 kilometers before merging with the Agno River.
Paje said the DENR was now looking into possible violations of mining and environmental laws that may have been committed by Philex.
Jasareno said Philex engineers, who had been working round-the-clock since the incident was discovered in the early morning of Aug. 1, successfully plugged the penstock of the tailings pond No. 3 to stop water and mine wastes from flowing into the river.
He described the penstock as a hollow elongated structure built within a tailings pond, with sidewalls or stop boards but open at the top where overflow water of the pond enters and drains to the drainage tunnel below it.
This, therefore, serves to prevent water from accumulating excessively in a tailings pond. The initial investigation showed that portions of the stopboards might have been displaced by hydrostatic pressure brought about by the unusually heavy rains in the area for the last two weeks, he said.
Philex is the country’s second leading producer of copper concentrate. It has been in operation in the last 57 years and employs about 2,500 regular workers, according to the DENR. It hosts a mining community deep in the highlands of the Cordilleras with a population of about 14,000.