Philippines: Mining or Food? by Robert Goodland and Clive Wicks for The Working Group on Mining in the Philippines Annex G: Geohazards and Earthquakes1 in the Philippines Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs The Brundtland Report, Our Common Future, UN World Commission on Environment and Development, 1987 In a world overflowing with riches, it is an outrageous scandal that more than 826 million people suffer hunger and malnutrition and that every year over 36 million die of starvation and related causes. We must take urgent action now. Jean Ziegler UN Special Rapporteur on the Right to Food, April 2001 DEDICATION The Working Group on Mining in the Philippines and the authors respectfully dedicate this report to all the courageous and dignified people who have been killed while protecting the environment and upholding human rights in the Philippine archipelago. Disclaimer The views expressed in this report are those of the authors and not necessarily those of the participating or supporting organizations. The authors have, however, done their utmost to reflect the views of the many people they met in the Philippines and the views and reports of the people and organizations who have commented on earlier drafts if this report. 250 Annex G: Geohazards and Earthquakes 2 in the Philippines Playing with Fire “The majority of the earthquakes and volcanic eruptions occur along plate boundaries such as the boundary between the Pacific Plate and the North American plate. One of the most active plate boundaries where earthquakes and eruptions are frequent, for example, is around the massive Pacific Plate commonly referred to as the Pacific Ring of Fire.” The Philippines are part of the Pacific “Ring of Fire” http://earthquake.usgs.gov/learning/ 2 For important information on Earthquake Hazards visit the U.S. Geological Survey Earthquake Hazards Program at http://earthquake.usgs.gov/regional/world/index.php?regionID=19 For Earthquake Facts see http://earthquake.usgs.gov/learning/ 251 Geohazards and Earthquakes 3 in the Philippines The Philippine archipelago of more than 7100 islands lies along the so-called Pacific "Ring of Fire," encircling the basin of the Pacific Ocean, where earthquakes and volcanic activities are common. The Ring of Fire has 452 volcanoes and is home to over 75% of the world’s active and dormant volcanoes. Ninety percent of the world’s earthquakes and 80% of the world’s largest earthquakes occur along the Ring of Fire. This is a direct result and consequence of plate tectonics and the movement and collisions of crustal plates. Philippine earthquakes in recent years have included one in Mindoro on 8 October 2004 and several in Mindanao, the latest being on 14 October 2008. The earthquake in Mindanao on 5 March 2002 killed at least 15 people and injured 100 more, with 800 buildings damaged or destroyed in southern and central Mindanao. In South Cotabato Province, landslides caused by this earthquake breached the crater wall of Parker Volcano and fell into Maughan Lake, creating a flood which washed away houses and flooded nine sub-districts. Local tsunamis with heights estimated at three meters were registered. On 16 July 1990 a severe earthquake registering 7.7 on the Richter scale struck the northern Philippines. The earthquake caused damage over a region of about 7700 square miles, extending northwest from Manila through the densely populated Central Plains of Luzon and into the mountains of the Cordillera Central. Over 5,000 people were reported dead or injured, and in excess of 2300 infrastructures were either destroyed or seriously damaged. Most of the Philippine islands are volcanic in origin. The Philippines is crossed by a number of tectonic faults which include Lingayen-Dingalan, West Luzon Shear Zone, Philippine Fault, along with several fracture zones. West of the Philippines, in the South China Sea, lies the Manila Trench, which is an eastward-moving subduction that has created a 900 km long volcanic belt from Taiwan to Mindoro. There are 37 volcanoes in the Philippines, of which 18 are still active. This means that an eruption occurred in the last decade and that a new eruption can be expected in the near future. The country has some of the world's most dangerous volcanoes, and Mount Pinatubo’s eruption in 1991 created the second largest eruption of the 20th century. Taal and Mayon volcanos create dangerous eruptions periodically. Nationally, the Philippine Institute of Volcanology and Seismology monitors the activities of volcanoes, earthquakes and tsunamis, as well as being mandated to mitigate disasters when any of them occur and promote sustainable development. The Institute also runs natural disaster risk reduction programmes which incorporate land use planning and information dissemination regarding potential hazards in areas near to active volcanoes. Large-scale mining is clearly an issue to be considered in such programmes. The Mines and Geosciences Bureau of the Philippines (MGB) is now conducting a geohazard mapping program which began in 2006 and is expected to finish by the year 2010. This is in line with the recent Presidential directive and National Disaster 3 For important information on Earthquake Hazards visit the U.S. Geological Survey Earthquake Hazards Program at http://earthquake.usgs.gov/regional/world/index.php?regionID=19 For Earthquake Facts see http://earthquake.usgs.gov/learning/ 252 Coordinating Council (NDCC) Resolutions to fast track the geohazards mapping programs along the eastern seaboard of the country. Funding of PHP60 million ($1,260,000) has been set aside for this purpose. In is a fact that most parts of the Philippines is vunerable to geohazards, often contributing to the increasing number of so-called natural disasters. The main objective of this program is to identify areas in the country that are vulnerable to various geohazards. Examples of geohazard phenomena are the impacts of heavy rains causing floods and landslides, deforestation impacts, volcanic eruptions and earthquakes. Specialized maps are being produced which contain information on the locations of the barangay centers and susceptibility to rain-induced landslides. Information will be made available to authorities responsible for infrastructure, land use planning and disaster-preparedness. In Region 9, this program has already been completed in more than 25 municipalities since this was initiated in 2006. Eighteen geologists were deployed from the MGB Central Office and MGB Regional Office No IX, to undertake programs in the critical barangays in Zamboanga del Sur on Mindanao. Induced seismic activity Induced seismicity refers to earthquakes and tremors that are caused by human activity. These can alter the stresses and strains on the Earth's crust. Induced seismicity in connection with ore mining has been reported for at least 100 years. The reason the authors were worried is that mining can leave voids in the ground and these can alter the balance of forces in the rock. If voids collapse they can produce seismic waves and reactivate existing faults causing earthquakes. The authors were concerned that many of the mining operations in the Philippines are proposed in areas of high seismic activity particularly near to fault lines and they questioned mining companies about induced seismic activity that might be caused by their operations. The companies did not seem to know much about it and the authors remain very concerned about the potential impact on induced seismic activity. In 1996 the Environmental Impact Statement System (EIS)[DAO 96-37], was established under Presidential Decree (PD) No. 1586, Establishing an Environmental Impact Statement System, Including Other Environmental Management Related Measures and for other Purposes stipulates additional requirements. These were a Health Impact Assessment and an Engineering Geological and Geohazard Assessment for applications covering housing and other land development and infrastructure projects. “Recently the Government has announced its interest on reducing the procedures and norms for environmental permissions. The DENR Secretary described them in October 2004 as ‘obstacles for private investment to the country’. This deregulatory approach could be considered positively if the idea is only to simplify the complexity of the current permissions system. But is seems that what the DENR is looking for is more to remove norms – rather than only to speed up the permissions - to attract more investors .” European Commission’s report, The Philippines Country Environmental Profile. 2005 253 “Mindanao Experienced 19 Quakes in 2 Weeks” 4 A 2008 newspaper report from Davao City’s Sun.Star stated that “Central and Southern Mindanao regions experienced a total of 19 earthquakes from the period of March 3 to 22, with the strongest magnitude registering at 5.3 in the Richter scale and epicentre located 153 kilometres southeast of the City of Mati, Davao Oriental”. Mati, is the area where BHP Billiton Hallmark mining project is located. To the west of this is where Xstrata intends to exploit copper and gold in the Tampakan area. The report states that “All quakes were tectonic in origin, meaning these were caused by the movement of the earth's crust. There are two major causes of earthquakes: tectonic and volcanic. Tectonic has to do with the movement of the earth's crust while volcanic has something to do with activities inside a volcano.” The Philippines are plagued with both earthquakes and volcanos. The Philippine Institute of Volcanology and Seismology (Phivolcs), from which we mined the data for this report, stated that “The tremor was measured at magnitude 4.3 and was felt at Intensity 2 in Caraga and Cateel, Davao Oriental”. “Kidapawan City registered the most number of tremors at 16 incidents from March 11 to 19. March 13 had the most incidents with 11 earthquakes in just a period of one day. Kidapawan quakes registered from 1.8 to 4.7 magnitudes.
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