Final ESR - Part 2 - Eskom

REVISED FINAL ENVIRONMENTAL SCOPING REPORT FOR THE PROPOSED COMBINED CYCLE GAS
TURBINE (CCGT) POWER PLANT IN THE AMERSFOORT AREA, MPUMALANGA PROVINCE
been attempted, to establish the possible cumulative impacts which may result from the
proposed project.
• Scoping Assessment
During the scoping phase of this study, the key aspects of air pollution were identified and
discussed for the construction, operational and decommissioning stages of the proposed
project.
8.1.3 Baseline Assessment
• Wind
For the proposed study area, both monitored meteorological data from the Underground Coal
Gasification (UCG) plant and modelled data 5 from the South African Weather Services
(SAWS) was made available. According to the SAWS modelled meteorological data, winds
originate predominantly from the eastern and western sectors (Figure 4.4c – Chapter 4).
Airflow in the study area is predominantly from the east (~15% of the time). From the eastern
vector wind speeds of between 3.7 and 5.8 m/s occur most of the time (~6%). Wind speeds
between 5.7 and 8.8 m/s also occur, but less frequently (~2%). Winds are westerly ~12% of
the time, with the wind speed most frequently between 3.8 and 5.7 m/s (~4%). Wind speeds
of greater than 8.8 m/s are also experienced infrequently in association with wind from the
west. According to the frequency distribution graph presented in Figure 4.4d (Chapter 4), low
wind speeds between 0.5 and 2.1 m/s occur most of the time.
In comparison, the monitored data from the UCG site (Figure 4.4a and Figure 4.4b – Chapter
4), also indicates winds predominating from the east and west but with wind speeds most
commonly between 3.8 and 5.7 m/s. This will result in a higher dispersion potential when
assessing the impacts due to the release of pollutants to the atmosphere, than would be case
when assessing impacts using the SAWS modelled data.
• Precipitation
The area under investigation lies in the summer rainfall region of South Africa, receiving a
total annual rainfall of 1008 mm. The seasonality of the rainfall for the area is outlined further
in Chapter 4 – Section 4.1.2. of this report.
• Temperature and Humidity
Daily summer temperatures range between ~2 °C and ~32 °C with an average of ~17 °C.
Winter temperatures range between ~ -8 °C and ~23 °C with an average of ~7 °C. The study
area experiences high relative humidity during the summer months in excess of 70%.
5
The Weather Services Unified Model was used for these purposes as hourly average data was required for use.
POTENTIAL IMPACTS ON THE SOCIAL 84
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ENVIRONMENTAL