Three deafening explosions were followed by thick black smoke that covered a portion of the Biga Pit inside the Carmen Copper Corp. (CCC) compound in Toledo City at noontime yesterday.
When the smoke cleared, all that remained were 15-meter-wide craters and the debris of 29 World War II bombs that were detonated underground.
Using a boom truck, an Explosives Ordnance Disposal (EOD) team of the military’s Central Command (Centcom) loaded 28 vintage bombs each weighing 150 pounds, plus one 1,000-pound vintage bomb on three trucks at dawn yesterday.
Each truck had a bed of one-foot-high soil to keep the bombs firmly in place.
Warning signs on the trucks read: “Danger. Explosives on board, keep distance.”
The convoy of 15 vehicles, including an ambulance, left at 4:30 a.m. from Kawit Island in Cebu City for the journey west to Toledo City at a speed of 60 kph.
They had to slow down to 40 kph upon reaching road curves along the Naga-Uling road, said Philip Zafra, chief of staff of Cebu City Mayor Michael Rama.
The convoy reached the CCC compound at 6 a.m.
Closed, secured
Preparation of the blast site was completed four hours later.
An EOD member who requested anonymity said boom trucks unloaded the bombs and positioned them in eight holes measuring six feet deep in the Biga Pit.
EOD personnel attached the C4 detonators at 8 a.m.
A water-pumping station and a decant tower near the blast site was vacated starting 8:30 a.m. said Josue Bordon, AVP for Administration of Mine Management for CCC.
Nearby roads were closed and secured by mining firm security personnel.
The 28 vintage bombs were distributed in seven holes while the 1,000-pound vintage bomb was placed in a separate hole at the far end of the blast site.
Cortex 10 were wound around the bombs before they were covered with soil.
One end of a fuse was attached to the bombs while the other end was left in open air for lighting.
The eight holes were divided into three groups, with each group connected to two lines of fuses to ensure simultaneous detonation, said military experts.
The fuses in each group were 30 to 36 feet long.
A match was used to light the fuses at 12:06 noon.
It takes a foot-long fuse about 30 to 35 seconds to burn.
Shock waves
After lighting the fuses, the CCC security, EOD and Special Weapons and Tactics (SWAT) personnel immediately drove off in three vehicles to a viewing deck, which CCC officials identified for guests and spectators.
The view area was two kilometers from the explosion site and was separated by the Biga waste water dam, which is 200 to 300 feet deep.
Three explosions were followed by thick black smoke 20 minutes after the fuses were lighted.
Two groups of the 150-lb vintage bombs were first to explode. The last explosion was caused by the 1,000-lb bomb.
Bordon said the wastewater dam absorbed the shock waves, preventing them from reaching the view deck.
An EOD member said the explosions could be heard within a three-kilometer radius.
But this was barely heard in the nearest residential area two kilometers from the Biga Pit.
Bordon said he was confident that the explosion would not cause untoward damage since the bombs were buried in rocky ground in an isolated part of the Biga Pit.
Welcome
The copper mine pit was abandoned after the old Atlas Consolidated Mining and Development Corp. ceased operations in 1994.
The Biga Pit is now used as storage and recycling area for wastewater of the mining operation.
EOD and Swat personnel returned to the blast site an hour after to check if all the vintage bombs were disposed.
All they found were craters formed by the powerful blasts and debris of the vintage bombs.
An EOD member said they used 80 of the 125 C4 bombs given by Camp Aguinaldo last Thursday. The unused explosives will be returned to the national headquarters.
Bordon said his company was prepared to pay for the explosive devices like the cortex 10, fuse and blasting cap that Orica Philippines Inc., CCC’s supplier, released for the detonation of the vintage bombs.
“If Orica charges us for the explosives devices, then we will pay for it,” he told Cebu Daily News.
Bordon said the Cebu city government is welcome to use the pit for detonating any vintage bombs they may find in the future.