Page 65 - Solid Waste Analysis and Minimization a Systems Approach

AN OVERVIEW OF ENVIRONMENTAL CONCERNS 43

World population: 1950 to 2050
10
9
9 billion
8
Population (billions) 6 4 billion 5 billion 6 billion 7 bi lion
8 billion
7
5
4
3
2
1 3 billion
0
1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 2050

Year
Figure 2.10 World population trends.

approximately 1.2 percent. By 2050, the world population is projected to be over
9 billion. Globalization and the development of third world countries are com-
pounding these issues as well. More people generating more waste is not a good
combination for the environment. Figure 2.10 provides a visual representation of
the projected population increases.
One of the central purposes of solid waste analysis and minimization is to reduce or
eliminate the environmental impacts of individual companies and industries. An
understanding of these impacts is critical, when addressing solid waste issues, to pro-
vide direction for reduction efforts. Some of these impacts are more important than
others, thus a comprehensive understanding will allow managers and engineers to
focus on more serious problems. This section provides an overview of these impacts
with a focus on the effects, not the sources. These impacts are

■ Space availability—As the world population increases and cities grow, the avail-
able space to dispose of solid waste decreases. By minimizing solid waste levels,
disposal space will also decrease making land available for other uses.
■ Landfill leachate—Leachate is the liquid generated from a landfill that is created from
decomposing waste. It’s created after rainwater mixes with the chemical wastes or liq-
uids present in the landfill. Once it enters the environment, the leachate is at risk of
mixing with groundwater near the site, which can have very negative effects.
Groundwater is the source of drinking water for over 40 percent of the urban popula-
tion, and up to 90 percent of the rural population. It was formerly assumed that this
source of water was not subject to contamination, but recent studies have shown that
groundwater can in fact become contaminated. Landfill leachate may be virtually
harmless or dangerously toxic, depending upon the characteristics of the material in
the landfill. Typically, landfill leachate has high concentrations of nitrogen, iron,
organic carbon, manganese, chloride, and phenols. Other chemicals including