Environmental Engineering Reference
In-Depth Information
is no guarantee that a leak will not occur. As noted above, plastic tears
and concrete dissolves over time.
Incineration
Burning of many hazardous industrial wastes such as
tar, paint, pesticides, and solvents at a temperature of 1,500°F prevents
the formation of dioxins, which affect the human endocrine system,
nervous system, and reproductive functions.
Chemical or biological
Chemicals are added to the wastes to make
them less toxic or bacteria eat the waste, resulting in a less toxic residue.
Proper disposal of toxic waste is a major problem in industrialized
countries. Approximately 4 billion tons of hazardous waste are shipped
within the United States each year, with more than 250,000 shipments
entering the transportation system daily. Disposal can cost $2,500 per
ton and takes up valuable landfi ll space. Moreover, because it is never
totally safe, nobody wants a toxic waste dump in their back yard or
even within an hour's driving distance. This is the reason that 90 percent
of the hazardous waste deposited on land is injected deep into the
ground in permitted wells; the remaining 10 percent is treated and dis-
posed of in a manner to minimize risk to human health and the
environment.
Another way to solve the toxic waste disposal problem is to pay
another country to take over the problem. Many Third World nations,
desperate to earn money, have become the unfortunate targets of waste
brokers—the middlemen between producers of waste and possible dump
sites. Transporting (often by sea) waste to another country runs the risk
of spillages, such as happens to oil tankers. Also, the receiving country
often lacks the expertise and technology to deal with the toxic waste
safely. Every country should take responsibility for its own hazardous
waste. If a country is smart enough to produce such stuff, it should be
smart enough to dispose of it safely.
Superfund: The Worst of the Worst
Thousands of toxic waste dumps and landfi lls are found across the
United States, the accumulation of many decades of largely irresponsible
disposal practices by today's standards. Studies in both the United States
and Europe have shown that mothers living within 1 or 2 miles of a
hazardous waste landfi ll site are one-third more likely to have babies
with birth defects.
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The farther away from such a landfi ll that the
mother lives, the less the likelihood that her child will have a birth defect
that affects the heart, nervous system, or blood vessels.
