SOMETHING SMELLS
By: Lourdes Ledesma
While the controversy rages around the proposed new landfill of Bacolod City, allow me to backtrack a bit (for the uninformed reader) and clarify what a landfill is all about, as compared to what the city presently has for its garbage dump. What it has now is an open, uncontrolled area, where unclassified garbage of all kinds is just dumped together, in a place near a water source and residential dwellings. For some who have not seen the place, it is located in Bgy. Felisa.
Responsible waste management is the process of removing wastes from living and work areas in ways that protect human health and the environment. Many cities in advanced societies opt for various strategies for solid waste disposal, and a landfill is just one of them. Waste disposal is the final stage after other processes have been done, such as recycling, waste reduction, reuse, energy recovery (methane gas), and leachate treatment. Incorporating all these processes in a sanitary landfill scenario require much capital and sophisticated equipment. Most communities may just opt for the entombment of their garbage in a simple landfill.
Still, a “simple” landfill is not so simple to construct. It is not just choosing a place for a garbage dump. By the way, open garbage dumps are now illegal in most civilized countries in the world. In third world countries in Latin America, Africa and Asia, the open garbage dump is the most primitive type. There is a trend toward upgrading these dumps into landfills. In this country our garbage dump has just become illegal, with the enactment of Republic Act 9003 (The Ecological Solid Waste Management of 2002). We’re trying to catch up with the rest of the world, but we still have to close our open dumps and construct landfills. Actually, the whole purpose of modern landfills is to safely entomb waste so that uncontrolled degradation doesn’t endanger ground water and so that the land can be used after the landfill is capped and sealed. Parks, golf courses and even airports have been built on top of closed landfills. Entombment of waste is designed to limit degradation to take place so slowly so that the surface of the landfill does not shift.
Besides the garbage type of landfill, there is another type modern cities use for construction and demolition waste, such as broken cement, asphalt, brick, metals, drywall, roofing, and old tires. Since these materials do not biodegrade, the requirements for this type of landfill are not so stringent.
There are several kinds of landfills:
1. Semi-controlled dump – this type, although one step above the open dump, has no engineering, leachate or gas effluent management, but has some operation in placement of waste and recovery. Scavengers are allowed.
2. Controlled dump – the same features, except for the addition of compaction of waste. Less scavengers.
3. Engineered landfill – has infrastructure, clay and plastic liners, containment of leachate and its treatment, passive ventilation of gas, compaction of waste and daily soil cover.
4. Sanitary landfill – has proper siting, infrastructure, leachate treatment, gas flaring (burning), compaction of waste and daily soil cover.
5. Sanitary landfill with top seal – same features plus a top seal of, and the entombment of leachate.
6. Controlled contaminant release landfill – same features except for a controlled release of leachate, and a final top cover. The monitoring of leachate and its environmental impact after the landfill has been closed continues for several years.
The requirements of a SANITARY LANDFILL are more stringent and require more technology, capital and monitoring. Is this the choice of our city? For example:
1. The choice of the site must meet environmental standards of safety, i.e., away from rivers, reservoirs, lakes, the ocean, and far from residential and commercial areas.
2. The landfill must be properly engineered and constructed to receive and hold waste. There are standards to be met, such as having several feet of compacted clay at the base, and then lined with several layers of thick flexible non-degrading plastic films to prevent leachate from entering ground water. The lining is protected by more clay. There should also be a system of pumping out leachate and treating it in holding tanks.
3. Methane gas, a product of biodegradation, is either converted into biofuel or oxidized safely into the air. It is a factor contributing heavily to global warming.
4. Compaction of waste and covering of soil daily to reduce vermin and odors is the responsibility of the landfill operator, and presupposes the use of bulldozers and other heavy equipment.
In the Philippines and in other Asian countries, the landfills are owned and operated by the municipality. In more developed countries, the landfills are owned and operated by private contractors, who are given tax credits or tax breaks. In the UK, for example, landfill operators who use their site for recycling, sorting and waste incineration can apply to have the relevant area designated as a tax-free area. The government also imposes a tax on certain types of waste deposited in landfill, in order to encourage recycling and reduce the amount of waste. Waste is weighed and is charged on a per ton basis, except for construction waste, which is charged a lower rate. The charges are passed on to the taxpayer as part of their utility bill or property tax, or a “pay-as-you-go” scheme.
Metro Manila operates two landfills: in Carmona and San Mateo. Smokey Mountain is in rehabilitation. Puerto Princesa inaugurated in March, 2006, a state-of-the-art engineered sanitary landfill facility, the first of its kind in the country and the first to fully comply with R.A. 9003. It cost P230 million and is a project undertaken jointly by the Department of Local Government (DILG) with funding assistance from the Asian Development Bank. In Mindanao, Tacurong City has built a Category 2 sanitary landfill, with a capacity of 75 tons per day, funded by the USAID.
Quo vadis, Bacolod City?
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