In the not-so-distant past, trash was simply dumped into a hole and forgotten. Those days are over. The advent of stricter environmental regulations, along with public demand for more responsible resource management, have led to sweeping changes in the way landfills operate. Over the last twenty-five years, the majority of landfills across the U.S. have been required to monitor their practices and put safeguards in place to protect our natural resources.

The City of Albuquerque's Cerro Colorado Landfill is on the cutting edge of this trend. Cerro Colorado uses modern technologies and stringent oversight of its operations to ensure the citizens of Albuquerque that their landfill is both cost efficient and environmentally safe. As a result, the Cerro Colorado Landfill has been recognized for excellence by the Solid Waste Association of North America.

The Solid Waste Management Department operates the Cerro Colorado Landfill. Located on a mesa top west of the downtown area, the landfill currently has a 20-year operating permit (April 2001 Renewed) for 180 acres of waste disposal. This state-of-the-art facility was opened in May of 1990 and takes in approximately 450,000 tons of  residential and commercial trash per year. Cerro Colorado is also permitted to take in and safely dispose of petroleum contaminated soils (from oil spills, leaking storage tanks, etc.) in a separate 5-acre area. Cerro Colorado currently has a life expectancy of 50 Years.

Who runs Cerro Colorado?

Cerro Colorado is regulated and monitored by the State of New Mexico's Environment Department. The landfill complies with all state solid waste management regulations, and in 1993 it was rated second among 160 landfills nationwide by the Solid Waste Association of North America (SWANA).

Commercial haulers with valid permits may dispose of trash at the landfill, while Albuquerque residents may take advantage of residential curbside trash pick-up or take their trash to one of three Convenience Centers for transfer to the landfill or recycling facility.

What happens to the trash at the landfill?

Collection trucks deliver an average of 1400 tons of garbage to Cerro Colorado each week day and some 300 tons per day on weekends. Safely disposing of this steady stream of trash is no simple task.

After the trash is logged at the landfill's weigh station, it is transported to the disposal area where it is spread and compressed by a special type of heavy equipment called a compactor. Then the trash is buried under a layer of soil in sectioned-off areas of the landfill called cells. The trash is covered daily with a 6-inch layer of soil, which controls odors and keep birds, rodents, and insects from getting into the waste.

The cells at Cerro Colorado are 20 acres each in size and are joined together as the landfill expands. Before any trash is put into a cell, it is first lined with a sheet of heavy-duty plastic material called HDPE (High Density Polyethylene). The HDPE cell liner helps protect the aquifer (water table) that lies 600 feet beneath the landfill from possible contamination by liquids, called leachate, that seep down through the layers of trash. Leachate is produced by a combination of liquids from waste material, rainwater and other liquids that are produced during the decompostion of waste. Leachate may contain contaminates that could pollute water supplies if allowed to enter the aquifer.

Futher protection from leachate is provided by a leachate collection system placed on top of the HDPE liner in each cell. This is a system of perforated plastic piping at the bottom of each cell that collects leachate and transports it to an HDPE-lined evaporation pond.

How is the landfill monitored for safety?

Ongoing staff training and daily random inspections of the truckloads of city trash arriving at the landfill help insure that no hazardous wastes make their way into the disposal area. In addition, leachate in the evaporation pond is sampled periodically for evidence of hazardous substances, and four groundwater wells near the landfill are closely monitored to insure that no harmful materials make their way into the aquifer.

Methane gas is a potentially harmful by-product of trash disposal that must be monitored closely. As buried waste decomposes, it naturally generates methane gas, which is potentially explosive. Tests for methane gas are conducted on a quarterly basis at Cerro Colorado landfill to ensure that the gas is not traveling beyond the landfill's boundaries and getting into nearby buildings.

Plans are in the works at Cerro Colorado to construct a gas collection system that could potentially process methane gas for the generation of electricity or as a direct source of gas. About 100 "gas-to-energy" projects using methane gas from landfills are in operation around the country. The extraction of methane gas for energy production is also being considered at the Albuquerque's old Los Angeles Landfill, at the site of the former Balloon Fiesta Park. Methane gas now being safely burned off at the Los Angeles site could potentially be converted into a usable energy supply.

What happens to the trash after it is landfilled?

Over time, trash that is landfilled decomposes into the soil. But for the majority of landfilled waste, the decomposition process is extremely slow—much more so, we're finding, than experts had previously thought. Depending on local environmental conditions, much of the trash in a landfill can remain virtually intact for hundreds, or thousands, of years. For example, when one of Albuquerque's old landfills was uncovered during the construction of a roadway, newspapers dating from 1948 were found intact and readable.

As our towns and cities grow, so do our landfills. The average landfill capacity in the United States is now 25 million tons; that's up from just 1 million tons a decade ago. Every ton of trash that we send to the landfill represents additional space required for disposal. The more trash we throw away, the greater the need for new or expanded landfills, often on land that might otherwise be used for housing or recreation. What's more, as you might have guessed from the discussion above, properly maintaining landfill sites is not cheap.

We can all help reduce trash disposal costs and preserve valuable land by helpling reduce the amount of waste that goes to the landfill. Find out how each of us can Reduce, Reuse, and Recycle waste so that less of it goes into the landfill.