MANILA - Fifteen quarrying firms around Mayon Volcano were ordered to halt their operations due to several violations, the Mines and Geosciences Bureau in Bicol said Thursday.

Nine of the operators were excavating outside their permit area while six firms have none or expired environmental compliance certificates (ECC), said MGB-Bicol director Guillermo Molina Jr.

The 9 firms were ordered to rehabilitate their areas of operation, while 6 firms were directed to secure an ECC, Molina added.

"The other permits not listed in the 15 may be allowed to continue operations subject to strict monitoring," he told ABS-CBN's Teleradyo.

Environment Secretary Roy Cimatu earlier ordered the suspension of quarrying operations around Mayon Volcano after initial investigation showed some quarry operators left their stockpiles in the middle of the rivers, which were then washed away by floodwaters and submerged houses.

Albay Governor Al Bichara complied with the order even as he said the debris that submerged houses during Super Typhoon Rolly's onslaught came from the top of the volcano.

Only one quarrying operation was near a community in Legazpi City, Albay that has been subjected to an inquiry by the city council, Molina said.

An illegal dredging operation in Guinobatan was halted in August following complaint from residents, he added.

• Cimatu suspends quarrying operations around Mayon Volcano
• Albay gov says to suspend quarrying operations after Rolly devastation

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