I have just received information that MGB-DENR representatives are in Marinduque at this moment to conduct monitoring of the dams following an M3.2 shallow tremor at the mine site about a week ago. I was told that MGB is set to visit the site in October this year but decided to inspect the dams now in view of recent developments.
Apparently, a more definitive action is currently being formulated by the new DENR at present as it monitors the mine site with the end in view to mitigate the threats posed by another mine wastes spill or dam collapse.
It will be recalled that local and foreign scientists have warned about a looming disaster from the mine site in view of the abandoned siltation dams of Marcopper.
5 years ago a report was filed by the late Gerald Querubin of Sta. Cruz, Marinduque for Inquirer, parts of which are reproduced below:
|Acidic blue water continuously flowing into Makulanit River and into Boac River. Photo: William Mirambil|
DENR bureau warns mine waste spills threaten 2 Marinduque towns
According to engineer Mario Alban of the MGB-DENR for Mimaropa the report on the monitoring activity conducted from Oct. 13 to 14 (2011), showed a “progressive erosion of highly erodible materials” at the slope of Marcopper’s Maguila-guila siltation dam that may cause eventual flooding along the Mogpog River.
The report said erosion had significantly altered the steep slope of the Maguila-guila waste dam, causing a rapid increase in the rate of siltation along its stream channels.
It also said that continuous erosion and movement of earth materials downstream of the Maguila-guila creek toward the Mogpog River would further aggravate the siltation problem in the lowlands which may result in eventual flooding.
The inspection also disclosed that the Maguila-guila siltation dam’s catchment reservoir is now heavily silted by bed-load materials. This heavy siltation of the dam may contribute to its imminent collapse, the report said.
Seasonal rains in 1993 caused intense flooding and the then newly built dam collapsed altogether.
The Maguila-guila dam is among the dams of Marcopper identified as in “imminent danger of collapsing” by the United States Geological Services as early as 1996.
If a flash flood occurs, 15 riverside villages and the low-lying villages in the town proper will be inundated, and will affect almost 50 percent of the town’s population.
|The permanent pollution caused by open pit mining.|
In the same field inspection conducted in October, the MGB monitored that the water level of the Tapian Pit was at 314.57 meters, less than 6 m short of the rim but 4 m more from a discharge tunnel situated at 310 m.
The Tapian Pit is a 130-hectare wide and 320-m deep hole that was created in the process of mining copper near the summit of Mount Tapian.
“Should the pit burst or collapse, an estimated 20 million cubic meters of tailings and another 8 million cubic meters of water will cascade down the Boac River that will spell disaster for the province’s capital town,” the report said.
|With copy of current newspaper as date mark, photo shows AMD flowing down from mine waste dumps on the abandoned mine. Photo: Luna "Pongkoy" Manrique|