Sustainable Geoenvironmental Engineering Practice - Sustainable Practices in Geoenvironmental Engineering - page 465

Unsustainable Towards sustainability

Overexploitation,
abuse, misuse, by
industry and
humans

Reuse, recycle,
conservation and
recharge

Recharge, water and
groundwater treatment

Contamination from
effluents, waste
treatment plants,
deposition of airborne
contaminants

Geoenvironment

Water and
groundwater
resources

Containment and
mitigation of
impacts from land
discharge of
wastes,
remediation

Soil fatigue and loss
of soil quality from
poor agricultural
management and
intensive agricultural
practices

Soil
resource

Environmentally
sensitive agricultural
management practices

Geoenvironment

Habitat destruction

Contamination by point
and non-point waste
discharges

Treatment and
neutralization of toxicants in
waste discharge streams

FIGURE 13.1
The beetle diagram shows, on the left-hand side, some of the major stressor impacts in and on the geoenvi-
ronment, groundwater, water, and soil resources. An idea of what might be done to seek sustainability of the
resources is shown on the right-hand side of the beetle.

13.2.1 Accidents and Unplanned Events

Accidents and unplanned events are at the root of many of the unsustainable actions shown
in the left-hand side of the beetle diagram (Figure 13.1). Leaving aside the unplanned events
and accidents in foundation and geotechnical engineering experiences, and focusing on
geoenvironmental events, the 1966 major colliery spoil tip failure (slippage) at Aberfan that
was responsible for the deaths of over a hundred individuals is an example of an unplanned
geoenvironmental event (McLean and Johnes, 2000), not because of the failure of the slip
itself, but also because of the leachates generated from such spoil tips. The height of the tips
together with the slope of the tips and the weather conditions contributed to the disastrous
slippage problems. These tips, heaps, and piles provided the source for leachates that threaten
the groundwater and water resources. If and when the leachates reach these resources, with-
out adequate protection of these resources from the chemical stressors, they will be impaired.
Exploration, drilling, extraction, and production of petroleum can impact the envi-
ronment at numerous points. Contamination of shores after oil spills can lead to oil that
can remain for decades at beaches or marshes. Pressurized hoses with cold or hot water
used for cleanup of spills on beaches, etc., may create more problems, for example, in the
case of the Exxon Valdez spill where the more than 200,000 tonnes of disposable diapers,
pads, clothing, and other waste materials used in washing individual stones on the cobble
beaches required landilling or burning (Graham, 1989). In addition, the hot spray used in
the cleaning activities is reported to have caused damage to the benthic fauna.