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Municipal Solid Waste Collection 111

FIGURE 5.2 Compactor-type
truck common in urban and
suburban neighborhoods.

Prior to the development of compactor trucks, open and closed noncompacting trucks were
used to collect solid waste. These vehicles are inefficient for MSW collection because they carry
a relatively small amount of waste and workers must lift waste containers high to place wastes into
the truck. Noncompacting trucks are still used for collecting bulky items like furniture and white
goods or other materials that are collected separately, such as recyclables and yard waste.
Noncompacting trucks may also be suitable for servicing small communities and rural areas.

5.3.7 AUTOMATED WASTE COLLECTION
Waste collection is a labor-intensive business, often requiring as many as three workers per vehicle
to lift and dump containers. With the advent of automated lifting systems, however, collection
requires fewer workers, thereby reducing labor costs and workers’ compensation claims.
Semiautomated and fully automated systems are two innovative approaches to MSW collection.
Both systems rely on special trucks with mechanical or hydraulic lifting systems and require cus-
tomers to use special wheeled carts. With semiautomated vehicles, crews wheel the carts to the col-
lection vehicle and line them up with hydraulic lifting devices mounted on the truck body, activate
the lifting mechanism, then return empty containers to the collection point. In fully automated vehi-
cles, drivers control hydraulic arms or grippers from the vehicle cab. Unless there are problems such
as the overflow of materials, improperly prepared materials, or obstructed setouts, the driver can
service a route without leaving the collection vehicle (Figure 5.3). The benefits of automated waste
collection include the following (U.S. EPA, 1999):
• Reduced injury risk: Increased automation typically reduces work-related lifting injuries
as well as puncture wounds and lacerations.
• Reduced vehicle needs: Fully automated collection increases (by up to 300%) the num-
ber of households served per hour. This increased productivity typically results in a
smaller fleet of vehicles.
• Decreased labor needs: Automated collection reduces crew size per truck. For semiau-
tomated collection, one- or two-person crews are typical. With fully automated systems,
the driver typically works alone.
• Reduced environmental impacts: Automated collection means fewer trucks, lower fuel
usage, fewer air emissions, and fewer traffic and safety impacts on community streets.
• Reduced tipping fees: Carts with lids help keep water, ice, and snow from setouts, which
also helps control the weight of setouts and decreases tipping fees.