The City Council is urging the Department of Environment and Natural Resources to evaluate the presence of leachate at the decommissioned Irisan dumpsite in light of the proposal to construct a leachate treatment plant in the area.
Earlier, Councilor Peter Fianza raised doubts about the need for a P35 million leachate treatment plant at the site.
He said the dumpsite had ceased operations following the issuance of a Temporary Environmental Protection Order in 2008.
He said the environmental health risks linked to leachate may have been mitigated given that over 15 years had passed since the dumpsite was ordered closed.
During the council’s session on May 6, Fianza said the city government requires the technical support of the DENR to assess the necessity of building a leachate treatment plant in the area to ensure responsible spending and avoid wastage of funds on unnecessary projects.
“Without a test, I don’t believe we should proceed with this project. We need to conduct a study to determine the presence of leachate and assess whether its levels warrant attention,” Fianza said.
He said closure plans were made in 2007 including pre-assessments and recommendations for stabilizing critical areas and constructing drainage systems.
However, in 2008, parts of the rehabilitated area were used to dispose of old waste, leading to a dangerous accumulation of garbage by 2011.
Fianza questioned the need for intensive leachate management given the age of the waste and natural attenuation processes.
City Administrator Bonifacio dela Peña said leachate persists and continues to have a significant impact even after 20 years.
Despite efforts during rehabilitation after the trash slide in 2011, he said leachate remains within the garbage formation.
He said there had been complaints from residents regarding the stench coming from the site, stressing the septic tank constructed by the Department of Public Work and Highways was inadequate in addressing the leakage of leachate.
He said currently, the leachate emission is minimal. However, during the rainy season, there is an expectation of a significant increase in leachate that will seep out from the area and flow downstream, affecting the community residing there.
He told the city council there is urgency in building this facility particularly with the impending rainy season when leachate leakage occurs.
“We can do the sampling to test the presence of leakage. But we can only do that during the rainy season because leachate leakage occurs when there is water. By then, it might be too late to address this problem,” dela Peña said.
Fianza said sampling needs to be done even if it entails waiting during the rainy season to make sure the constructed facility fulfills its intended purpose.
The proposed facility will occupy the same site as the existing septic tank but on a significantly larger scale, expanding fivefold to cover the entire footprint of the former dumpsite.
The City Engineering Office is currently in the process of preparing the program of works for the proposed project, which is based on the project design provided by a private firm pro bono.
Dela Peña said the leachate treatment plant’s operation would span approximately 30 to 35 years before effectively eliminating the leachate.
Councilor Jose Molintas also suggested the DENR should conduct a study on the presence of methane, a byproduct of the garbage formation at the former dumpsite.
Methane is dangerous due to its flammability, potential for asphyxiation in high concentrations, contribution to climate change as a potent greenhouse gas, and risk of explosions in areas with in adequate ventilation.
The former dumpsite has undergone a transformation into an eco-park, aiming to become a new attraction while also addressing environmental issues.
Dela Peña said the lingering stench of garbage needs to be eliminated to fully use the area as an appealing eco-park and this could be achieved through this proposed construction of a leachate treatment plant.
Councilor Fred Bagbagen expressed his support for this initiative.
He said he will back it as long as the city government uses the appropriate technology and methodology. – Jordan G. Habbiling
