Geoenvironment Impact Mitigation and Management - Sustainable Practices in Geoenvironmental Engineering - page 357

• The objectives for restored site functionality by the stakeholder undertaking the
restoration do not coincide with the pre-impact state site functionality—meaning
that the stakeholder plans to develop the impacted site and has to remediate the
site before implementing site development. A good example of this is the reme-
diation of a brownield site so as to be able to provide for development of housing
projects. (A brownield site, generally in an urban setting, is one that has been
impacted by various kinds of chemical stressors.)
• The extent of site restoration means remediating the impacted site to a state that
may or may not meet the pre-impact state level—depending on the interests of
the stakeholder conducting the restoration, and more importantly, depending on
regulatory acceptance of site restoration plans. This restoration plan assumes that
site restoration will be implemented to a level that is on a lower level of site func-
tionality as compared with pre-impact levels. Under such conditions, regulatory
permission is the key to implementation of site restoration plans.
• The type of restored site, applied technology, and extent of site restoration plans will
be decided in accord with regulatory requirements and public acceptance—with
the latter being of utmost importance. In instances where the impacted site directly
involves the public at the impacted site, it is not a surprise to expect that the affected
public would want to “have a say” in what type of site restoration scheme is being
considered, and in particular, how the restored site will impact their daily lives.
Under such circumstances, combined regulatory-public hearings are required.
10.3 Stressor Impacts and Mitigation
The nature and types of stressors have been discussed in the previous chapters and
have been classiied or grouped according to their actions or impacts in the geoenviron-
ment (Section 2.1.1 in Chapter 2), e.g., thermally, hydraulically, mechanically, chemically,
geochemically, and biologically mediated. Included in the discussion in Section 2.1.1 in
Chapter 2 are some of the main sources of stressors and the encountered impacts from the
various kinds of stressors. Mitigation of stressor impacts is a course of action that assumes
(expects?) that source control is not available. Such is the case for most, if not all, natural
geo-disasters such as earthquakes, tsunamis, tornadoes, hurricanes, etc. For geo-disasters
that occur as a result of human activities, source control can minimize the number and
intensity (concentration, strength, magnitude, etc.) of stressors from the source.
10.3.1 Geo-Disaster Mitigation and Protection
Disasters occurring in the land compartment of the geoenvironment have often been
termed as geo-disasters . There are two distinct causative sources for geo-disasters:
1. Naturally occurring events: earthquakes, tornadoes, hurricanes, and drought that
result in geo-disasters and
2. Human related: disasters occurring directly and indirectly due to human activi-
ties such as failure of embankments and retaining walls, foundation failures due
to failure in supporting capacity of the ground, contamination of ground by non-
point sources and by fallout from smokestack emissions