Starting up; early stages - Introduction to Environmental Impact Assessment - page 110

provide a more balanced listing of both the biophysical and socio-economic elements (see
UNEP 1981). Table 4.2 provides an example of a framework for analysing each baseline
sub-element.

Table 4.2 Framework for analysing baseline sub-
elements: example of use

Sub-
element

Objectives Required information/

specialist(s)

Methodology Findings/

measurements

Water
quality

Protection of
human health and
aquatic life

Existing water quality;
possible sources of
pollution: run-off,
leakage from waste
treatment system,
surface seepage of
pollutants, intrusion of
saline or polluted water;
capacity of treatment
system Water quality
analyst; aquatic
biologist; water
pollution control
engineer; sanitary and
civil engineers

Laboratory analyses
or field
measurement of
water quality;
pollution indices

Potential for
degradation of
water quality;
safety of potable
water

Surface
waters

Protection of:
plant and animal
life; water supply
for domestic and
industrial needs;
natural water
purification
systems;
groundwater
recharge and
discharge;
recreation and
aestbetic values

Location of surface
waters streams, rivers,
ponds, lakes, etc.;
surface water volume,
flow rates, frequency
and duration of seasonal
variations; 7-day, 10-
year low flow; water
uses; ecological
characteristics;
recreation and aestbetic
uses Hydrologist;
ecologist

Measurement of
proximity of site to
surface waters; field
measurement of
volume, rate and
direction of water
movement;
categories of water
usage; ecological
assessment—see
ecology element

Potential
modification of
volume, rate and
direction of water
movement; impact
on ecological
character; degree
and type of water
usage

( Source: UNEP (Industry and Environment Office) 1981.)

4.7.2 Sources and presentation of data
The quality and reliability of environmental data vary a great deal, and this can influence
the use of such data in the assessment of impacts. Fortlage (1990) clarifies this in the
following useful classification:

• “hard” data from reliable sources which can be verified and which are not subject to
short-term change, such as geological records and physical surveys of topography and
infrastructure;