Transfer Stations
Rural Transfer Station Design
Since small transfer stations in rural or tribal settings receive considerably lower volumes of waste and customer vehicles than large urban or suburban facilities, many of the design criteria will simply not apply. Cost frequently is a major consideration for small rural transfer stations, limiting what can be done. Consequently, rural transfer stations are often uncovered or partially covered facilities. Partially covered sites might be enclosed on three sides with the vehicle entrance side open, or simply have a roof with no walls.
A common design uses a single open-top trailer situated beneath a raised customer tipping area. The raised customer tipping area allows customers to back up to the trailer or drop boxes and directly unload their waste into the roll-off trailer. A hopper is not usually used. When constructing a raised tipping area, taking advantage of natural grades within the site can reduce construction costs. If favorable grades do not exist, a simple earthen retaining wall and access ramp can be constructed to create the multilevel layout desired.
Some type of safety restraint should be incorporated on the tipping area to guard against falls. Using a removable constraint, such as a rope, chain, gate, or posts, allows tipping vehicles to unload waste unimpeded and facilitates site cleaning. Driving surfaces ideally are paved to minimize dust generation, but all-weather gravel surfacing is a cost-effective alternative to asphalt pavement. Another alternative is hosing down dirt areas during operating hours. The use of drop boxes requires a concrete or asphalt pad. Ideally, the facility is surrounded by a fence and gated. The gate should be locked during non-operating hours to keep out large vectors, trespassers, and illegal dumpers. Fences also are helpful in containing windblown litter. It is not uncommon for remote sites to lack water, sewer, or electrical service.
Another design approach utilizes a completely contained modular system, such as the system pictured below. These types of systems are prefabricated and can be quickly assembled in the field. The waste collection bins are completely sealed and are animal- and people-proof. Waste is deposited into the sealed bin by one of two methods. A small sliding door on the front panel can be opened by hand allowing small waste loads to be deposited, while the entire front panel can be raised to allow collection vehicles to unload. Raising the front panel cannot be done by hand and requires a power source. For isolated sites lacking electrical power, vehicle drivers can use a power take-off or a hydraulic connection from their collection vehicles to lift the front panel. To unload the system, the transfer vehicle pulls along side the container which is tipped up, dumping the waste into the waiting vehicle.
Again, if power is not available on site to tip the container, hydraulic power from the transfer vehicle itself can be used. This feature makes such arrangements ideal for unmanned or remote transfer stations. If desired, or required by state, tribal, or local regulations, leachate collection tanks also can be installed onsite.
—www.epa.gov