The Department of Environment and Natural Resources-Mines and Geosciences Bureau (MGB) has ordered the suspension of  mining operations of Philex Mining Corp. in Padcal, Tuba, Benguet even as government authorities declared that the recent  wastes spillage  has already been contained.
The suspension, according to the MGB, would remain until such time that the integrity and safety of its tailings pond No. 3 has been assured.
Civil Defense Office administrator Benito Ramos said the leak was already contained and leak from the tailings pond was already sealed and repaired by Philex.
Government scientists were dispatched to check the possible effect of the discharge on aquatic life and the quality of water on the Agno River and a tributary after the Aug. 1 discharge, he said.
The spillage threatens to contaminate Agno River, one of the country’s largest waterway.
Department of Environment and Natural Resources (DENR) Secretary Ramon Paje said the
suspension order issued on Aug. 2, 2012, remains in effect as of yesterday.
The accidental discharge of water and sediments from one of the two underground tunnels that drains water from the penstock of tailings pond number 3 of  Philex has been stopped yesterday afternoon at about 5:00 p.m.
According to MGB Director Leo Jasareno, Philex has three tailings ponds but only tailings pond 3 is actively used.
The two other ponds have been decommissioned and rehabilitated as forest areas.
Paje said the DENR-MGB has completed its initial assessment of the situation, including the impact of the water and sediment discharge on the river system in the surrounding areas.
The ocular inspection done by the MGB and the Environmental Management Bureau (EMB) yesterday found that the San Roque Power Dam has not been affected by the discharge.
Laboratory analysis of water samples  is continuing.
The dam is situated  about 30 kilometers downstream of Agno River from its convergence with Balog River.
The drain tunnels of Philex discharge their water load into the Balog River that, in turn, runs for about 2.5 kms. to converge with Agno River.
Paje said  the DENR was now looking into any violations of mining and environmental laws that may have been committed by Philex.
Jasareno said Philex engineers, working round-the-clock since the incident was discovered early morning of Aug. 1, 2012, successfully plugged the penstock of the tailings pond 3 to stop water and sediments from passing thru it and into the drain tunnel.
Jasareno described the penstock as a hollow elongated structure built within a tailings pond, with sidewalls or stopboards but open at the top where overflow water of the said pond enters and drains to the drainage tunnel below it.
This, therefore, serves to prevent water from accumulating excessively in a tailings pond.
Initial investigation showed portions of the stopboards might have been displaced by hydrostatic pressure brought about by the unsually heavy rains in the area for the last two weeks,  Jasareno said.
Philex is the country’s second leading producer of copper concentrate. It has been in operation in the last 57 years.
In 2011, its gross sale from its copper, as well as gold and silver by-products, ran into billions of pesos.
The mine employs about 2,500 regular workers. It hosts a mining community deep in the highlands of the Cordilleras with a population of about 14,000.
The government scientists concluded the slime and silt did not reach the Agno River and the San Roque dam.
Both the government and Philex gave no estimates on how much mining waste had been discharged, nor when the mine would resume operations.
Philex vice president Mike Toledo insisted the spillage consisted only of water and sediment, which he said was “non-toxic and biodegradable.”
The discharge caused no casualties, he added.
The company said heavy rain from successive tropical cyclones, including Typhoon Saola that killed at least 39 people earlier in the week according to an updated government count, had weakened the tailings pond structure.
The company’s shares plunged 7.59 percent on Friday after news of the spill and shutdown were made public.
The accident came amid intense public debate about the mining industry in the Philippines, which is believed to have some of the biggest mineral reserves in the world.
However, the wealth has been largely untapped, partly because of a strong anti-mining movement, while poor infrastructure and security concerns have also kept investors away.