February 1, 2007
For many waste collection companies, the need to locate, construct and operate a transfer station is becoming more obvious and important to their ability to stay competitive in the marketplace. Industry statistics have shown that, since the early 1990s, waste transport has increased by about 170 percent and waste generation by 20 percent.
The increase in the distance that waste is traveling for disposal is fueled by the continued closure of smaller landfills and the emergence of “megafills,” whose location and environmental setting allow large-scale disposal. The sites of these megafills are, by necessity, in remote areas that necessitate the large-scale transport of waste.
Perhaps the most obvious example of this trend is in New York City and its surrounding metropolitan areas (southeastern New York State, northern New Jersey and southern Connecticut) where almost all of the landfills have closed, and communities are shipping their waste to sites in Pennsylvania, Ohio and Virginia that range from 100 to 400 miles away. The price for this transfer and disposal has risen to more than $75 per ton, and the increase shows no signs of a letup.
As the number of landfills has decreased, the number of transfer stations has increased. The siting of transfer stations is critical to transporting waste in the most efficient manner to disposal facilities in remote locations. Historically, waste transfer has been predominantly by truck, but there are a number of other methods that deserve consideration.
Alternatives to traditional truck transfer include barge and rail transport. All things being equal, barges are the most efficient method for transporting waste. For instance, according to the U.S. Department of Transportation's “Environmental Advantages of Inland Barge Transportation” report, one barge has the cargo capacity of 30 jumbo-sized rail cars and 120 large semi-trucks. Furthermore, research has shown that barges require less fuel than rail cars and significantly less than trucks to move the same amount of freight. However, such advantages are tempered by loading and unloading costs as well as the expense of transporting garbage to the landfill working face.
Barge and rail transport become inefficient when loading and unloading stations are located significant distances from transfer stations and landfills, requiring the waste to be moved to a landfill over public roads after it is unloaded from a barge or train. Since there are few landfills in the United States with direct barge access, barging is the best choice in only a very few instances.
Considerations for siting a transfer station include:
location near a rail or barge facility;
truck routes; and
An ideal transfer station site would be at least several acres in size and have easy access to rail and barge facilities as well as highways, which would allow the site's operators the flexibility to transport waste for disposal by the means offering the most attractive financial package.
When designing a transfer station, planners will have to take several factors into consideration, including the site footprint and location; the turning radius of the vehicles that will be using the facility; how the tipping floor can best accommodate the expected waste storage; and how to arrange truck queuing to avoid creating a backup of trucks extending off of the site, particularly during peak delivery times.
Planners also should consider whether waste that is processed at the transfer station will be placed into containers that are used for barge, rail and, to some extent, truck transport. A typical 20-foot-long, 12-foot-high and 8-foot-wide lidded container may be loaded with up to 22 tons of waste in most states. Its size allows for four of these containers on a railcar, and they may be stackable on a barge. Some transfer facilities have loadout tunnels that are two containers wide, which allows either a second container to be loaded and/or a machine or truck to bypass the container being loaded.
Another trend in transfer stations is the use of fixed-mounted “pole” cranes to move waste over the floor and/or load trailers and containers. These electrically driven machines are efficient and very productive and are typically substantially less expensive than track-mounted loaders. Although the track-mounted type of equipment is more flexible in terms of being able to traverse the floor, the electric pole crane has a long reach, which allows it to pick up and easily move waste over a large area.
As the trend to transport waste from transfer stations to remotely-located landfills continues, transfer station owners will incorporate changes in siting, planning and design to ensure flexibility and the ability to move waste in the most cost-effective manner.
Richard A. Peluso is president of Cornerstone Environmental Group, a Goshen, N.Y.-based engineering consulting firm.
WANT TO LEARN MORE?
WasteExpo attendees will have an opportunity to learn more about the issues surrounding the construction of transfer stations. On Monday, May 7, from 1:45 p.m. to 3 p.m., the conference will host the “Considerations in Siting and Operating Transfer Stations” session.
The session will explore a number of issues: the economic feasibility of transfer stations, site selection, capital costs, design and the importance of community involvement.
Steve Smith of Scottsdale, Ariz.-based Hydro Geo Chem Inc. will moderate the session. Michael Kalish of Long Beach, Calif.-based SCS Engineers and Vince Murphy of Waste Management of Arizona Inc. are scheduled to speak.
WasteExpo will take place May 7-10 in Atlanta. For more information, visit www.wasteexpo.com.