Settling ponds, silt fences and gabion check dams for environmental management and protection
Bayog, Zamboanga del Sur / July 2020 – TVI Resource Development Philippines Inc. (TVIRD) – holder of a 4,779-hactare Mineral Processing Sharing Agreement (MPSA) area in Bayog Municipality, Zamboanga del Sur – is conducting a wide-scale environmental clean-up activity in its area to address damages caused by decades of illegal small-scale mining activities prior to its entry.
Particularly, the company has rolled-out reforestation activities, the construction of settling ponds, the installation of silt fences and gabion check dams as well as bi-weekly water quality monitoring to protect the town’s creeks and rivers that lead to Sibugay River – the catchment basin of Zamboanga del Sur. The river is the source of irrigation for Bayog’s rice production, including those of other towns in the province. It also irrigates the rice-producing municipalities of Sibugay itself: Imelda, Siay, Buug and Diplahan. Fishponds in Sibugay Province also depend on the river.
According to TVIRD Head Forester and OIC of its Mine Environmental Protection and Enhancement Office, Andrew Namayan, as of the second quarter of 2020, TVIRD has spent close to Php8.0 million in establishing these critical infrastructures to protect the region’s inland bodies of water.
Protecting the rivers
Namayan disclosed that TVIRD constructed a total of 15 settling ponds, 52 silt fences and 12 gabion check dams to further filter the water discharges that lead to Sibugay River; therefore, ensuring good ambient water quality for the communities.
In line with the Water Resource Management component of TVIRD’s approved Environmental Protection and Enhancement Program (EPEP), these activities are determined prior to the development of the Balabag Project in order to assess the impact of future operations and the establishment of environmental structures and mitigating measures to prevent and minimize these impacts.
Environmental structures are also located primarily in disturbed areas where there is a high volume of run-off water in order to reduce sedimentation. Additional mediums like Geotextile filter fabric are used as silt fences, which prevent sedimentation by effectively trapping suspended solids like silt, sand, mud and stones.
Namayan’s department takes water samples from 21 on- and off-site water sampling stations – which are analyzed for Total Suspended Solids (TSS) by the company’s Assay laboratory and a government-accredited laboratory.
“So far, laboratory results from both in-house and outside laboratories show that bodies of water on-site and off-site are within government standard,” Namayan said.
Protecting the environment
These initiatives are aligned with TVIRD’s EPEP, which is approved by the country’s Department of Environment and Natural Resources (DENR). Other components include Land Resource Management, Air Quality, Noise and Vibration, Conservation Values, Environmental Research, Training and other activities.
To keep land disturbance at a minimum, TVIRD has planted a total of 120,382 seedlings in 107.57 hectares within its MPSA as of June this year. The company also placed coco mats on slopes and planted Vetiver Grass (Chrysopogon zizanioides) and runners to further prevent soil erosion. The slopes are also “benched” to add stability.
Healing the land
In 2012, the provincial government of Zamboanga del Sur mobilized the dismantling of illegal mining operations in Sitio Balabag in Bayog Municipality – operations that contaminated the bodies of water in the area. A Cease and Desist Order was implemented by the Philippine National Police, National Bureau of Investigation, the Armed Forces and other concerned agencies led by the DENR’s Mines and Geosciences Bureau.
Under the Bureau’s supervision, TVIRD was able to rid the area of hazardous chemicals left by illegal miners in shallow waste ponds. The company also embarked on a major clean-up activity to address the indiscriminate cutting of trees, un-engineered tunnels and earth-moving, and mine wastes laced with mercury, cyanide and other hazardous chemicals.
A current TVIRD employee recalls how he was forced into child labor under the small-scale operators back then: “Panginabuhi tong amo. Parehas sa uban nanginabuhi lang mi” (It was for livelihood. Like the others, it was our only way to earn a living).
He also admitted that financiers of illegal mining operations do not mind the environment; they just want the gold. “But with TVIRD, it’s different. We’re not yet operational – but the company is already protecting our land,” he said.
*******