Water flowing at TSF3’s newly built open spillway | JOURDAN CASELA

Water starts flowing onto Padcal’s spillway from TSF3

Wednesday, August 21, 2013

Newly built drainage part of urgent remediation measures on tailings pond

Water is now flowing onto the newly inaugurated open spillway of Philex Mining Corp. in Itogon, Benguet from its tailings pond at Padcal mines, following four days of strong rains brought about by typhoon •€œLabuyo•€ followed by the southwest monsoon.   

Philex Mining President and CEO Eulalio Austin, Jr. said Tuesday night the thickness of water flowing is 0.6 meters, adding that no water is going into the Penstock B of Tailings Storage Facility No. 3 (TSF3) after the levels of its stopboards were raised.  

€œI am pleased to inform you that Padcal starts to experience good weather after four days of strong rains,•€ he said in a text-messaging blast to all Philex Mining employees. He also said the downpour occurred between Friday night and Monday night, prompting water to overflow from TSF3 onto the spillway.  

The P327-million spillway, designed to replace TSF3•€™s underground drainage system, had two of its three chutes done at the end of June, in time for the rainy season. The third chute will be undertaken during the next dry season.  

Philex Mining earlier said TSF3•€™s Penstock A and its connecting Tunnel A had been condemned and sealed off with concrete after the discharge of water and sediment on Aug. 1, 2012, following historically unprecedented rains brought about by two successive typhoons. The pond•€™s Penstock B and Tunnel B, on the other hand, may still be used if needed.  

Once fully completed, the spillway, whose chute measures 12 meters wide and 300 meters long, will be able to channel up to 1,500 millimeters of rain over 24 hours•€”or more than three times the 455 millimeters of rain that typhoon •€œOndoy•€ dumped over a 24-hour period in 2009.  

Michael Toledo, senior vice president for Corporate Affairs at Philex Mining, said the open spillway is part of Padcal•€™s urgent remediation measures, which have progressed significantly since government regulators allowed the company to resume temporary operations for four months from March 8•€”and extended this indefinitely from July 7.  

He stressed these measures also include the filling of a void in the pond created by a sinkhole that occurred during the tailings-leak accident; a total of 3,069,777 cubic meters (cu m) of fresh tailings were deposited into TSF3 between March 8 and July 2 alone for this purpose.  

Libby Ricafort, vice president at Philex Mining and resident manager of Padcal operations, earlier said about 3.5 million cu m of fresh tailings would fill the void and create a beach in the pond•€”designed to hold solids, not liquid•€”that would push accumulated water away from the embankment and onto the spillway.  

Philex Mining also fabricated a concrete sphere of 6 meters in diameter that has been positioned strategically at 587 meters above sea level in the southern part of the pond•€™s offset dike, ready to be released should another sinkhole occur.  

Last month, the Mines and Geosciences Bureau allowed Philex Mining to continue operating while government has yet to decide on the full resumption of Padcal operations after four months of temporary production or 11 months since the tailings-leak accident last year.