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Asbestos: General Information for Handling and Disposal
General Information
Asbestos has been used commercially in
this country since 1880. A naturally occurring mineral, it became a popular
product because it is non-combustible, resistant to corrosion, has a high
tensile strength and low electrical conductivity. These qualities, combined
with its relatively low cost, resulted in the development of an estimated
3,600 different commercial products containing asbestos.
As a natural mineral, asbestos is not
water soluble and does not move through groundwater to any appreciable
extent. Based on studies of other water insoluble particles of similar size,
the expected migration rate is approximately 1 to 10 centimeters per 3,000 to
40,000 years. Thus, asbestos is not considered to be a significant
groundwater contaminant.
Although asbestos does not "move" with
groundwater, it still may be a drinking water contaminant. Many thousands of
miles of municipal supply and waste water lines were built with asbestos
cement pipe (also known as transite pipe). Corrosive water, common in New
England, liberates asbestos fibers in this type of pipe and transports them
to households. The actual breakdown process can be caused by one of the
following: a scrubbing action caused by water velocity at the perimeter of
the pipe or a break down of the Portland Cement Asbestos Fiber Binder either
mechanically or chemically. It has been estimated that approximately 5
percent to 10 percent of the population nationwide may be drinking water that
contains greater than 300,000 asbestos fibers per liter.
The current asbestos fiber content of
drinking water that is permitted according to the Summary of United States
Environmental Protection Agency (EPA) Required, Recommended, and Proposed
Drinking Water Standards for Community Water Supply Systems are 7.1 million
fibers/liter unlimited consumption. Medical studies have determined that the
risk level for a person consuming 2 liters of water/day contaminated with
300,000 asbestos fibers/liter for 70 years would have a one (1) in 100,000
chances of developing gastrointestinal cancer. In most cases, the fibers
would simply pass through the digestive tract and be discharged as body
waste. The probability of asbestos contaminated sludge from a waste water
treatment plant creating a problem by reintroducing the fibers to the earth's
atmosphere is considered insignificant, according to researchers at Cornell
University, Ithaca, N.Y.
Based on the results of a number of health
studies, it is recognized that asbestos can endanger human health. The
inhalation of asbestos fibers in high concentrations is known to cause a
debilitating and irreversible respiratory illness known as asbestosis, as
well as lung cancer and mesothelioma cancer. The latency period associated
with these diseases can involve several decades. Because inhalation is the
exposure route of concern, it is important to prevent asbestos fibers from
becoming airborne, being directly contacted, or entering surface waterways.
In the early 1970s, the use of asbestos in
the United States peaked at about 800,000 tons/year. The USEPA became
concerned at that time with the disease-causing potential of asbestos by
airborne fibers. Regulatory action, combined with voluntary initiatives,
lowered the annual United States use to 217,000 tons/year in 1983. On July
12, 1989, the USEPA issued a final rule under Section 6 of the Toxic
Substance Control Act (TSCA) to prohibit, at staged intervals, the future
manufacture, importation, processing, and distribution of commerce in the
U.S. of most asbestos containing products. This rule was challenged in court
by the asbestos product manufacturers and on November 5, 1993 the USEPA
confirmed that in court proceedings the references to phase and ban of
asbestos products in section 6 of the 1989 TSCA were overturned. Asbestos
products such as asbestos pipeline wrap, vinyl/asbestos tile, asbestos wall
board, asbestos clothing, asbestos-cement corrugated and flat sheeting
asbestos roof belt, and asbestos-cement shingles can continue to be
manufactured in the United States. Therefore, asbestos will continue to be a
component of various industrial waste streams and a contaminant of industrial
areas and industrial waste sites. Construction and demolition debris dumps
are facilities where asbestos is often improperly disposed after removal from
schools, workplaces, dwellings, and other structures.
Source:
N.H. Department of Environmental Services
Waste Management Division
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