College of Agriculture and Environmental Sciences
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HES4810: Impact Mitigation and Management
Assignment 2 — Semester 1, 2026
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HES4810
Module Code:
Impact Mitigation and Management
Module Name:
Assignment 2 (40% of Year Mark)
Assignment:
727827
Unique Number:
04 July 2026
Due Date:
65
Total Marks:
Submitted in partial fulfilment of the requirements for HES4810 — UNISA 2026
,UNISA | HES4810 Impact Mitigation and Management — Assignment 2
Question 1: Environmental Impact Pathways
Environmental impact pathways provide a structured way of tracing how a project’s activities
generate environmental consequences through a sequence of cause-and-effect relationships (De-
partment of Environmental Affairs, 2017). This question applies that framework to a hypo-
thetical road construction and upgrading project, using the National Route 2 (N2) expansion
corridor in KwaZulu-Natal, South Africa, as the reference project context.
1.1 Five Environmental Impacts Associated with the Project
The following five environmental impacts have been identified for the N2 road expansion project:
1. Air quality degradation from construction dust and vehicle emissions.
2. Noise pollution affecting surrounding residential communities and wildlife.
3. Habitat loss and fragmentation resulting from land clearance along the road corridor.
4. Surface water contamination from construction runoff and sediment discharge.
5. Soil erosion and compaction caused by earthmoving operations during construction.
1.2 Cause-and-Effect Pathways: Activity – Aspect – Impact
The following table presents the full cause-and-effect pathway for each identified impact (Borda-
de-Agua et al., 2017; Sandoval et al., 2022):
Table 1: Cause-and-Effect Pathways for N2 Road
Expansion Project
Impact Activity Aspect Impact Descrip-
tion
Air quality Earthmoving, Particulate matter Reduced air qual-
degradation blasting, heavy (PM10, PM2.5) ity in surrounding
vehicle movement and exhaust gas areas; respiratory
emissions health risks for
workers and nearby
residents
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, UNISA | HES4810 Impact Mitigation and Management — Assignment 2
(Table 1 continued)
Impact Activity Aspect Impact Descrip-
tion
Noise pollution Operation of Elevated deci- Disturbance to resi-
heavy machinery; bel levels above dents, disruption of
rock blasting; in- ambient thresholds wildlife communica-
creased vehicle tion, and potential
traffic hearing damage to
on-site workers
Habitat loss Vegetation clear- Permanent re- Loss of biodiversity,
and fragmenta- ing; excavation; moval of natural isolation of wildlife
tion road surfacing vegetation cover populations, and
and wildlife move- increased exposure
ment corridors of fauna to road kill
risk
Surface water Site drainage; Runoff carry- Elevated turbidity,
contamination cement mixing; ing sediment, reduced dissolved
fuel storage and hydrocarbons, oxygen, and toxicity
spillage and chemical in receiving water-
compounds into courses affecting
streams aquatic organisms
Soil erosion Heavy machinery Destabilisation Accelerated erosion,
and compaction operation; removal of soil structure loss of productive
of topsoil; strip- and loss of organic land, and increased
ping of vegetation matter sediment load in
stormwater systems
Key Distinction
The distinction between an aspect and an impact is often confused in EIA practice.
The aspect is the element of an activity that interacts with the environment (such as
dust emissions), whereas the impact is the actual environmental change that results
from that interaction (such as degraded air quality). Understanding this distinction is
fundamental to designing effective mitigation measures (Department of Environmental
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