Azura-Edo Independent Power Plant Environmental Impact ... - IFC

NIPP were used for NO 2. The results show a relatively clean air shed with low
values of SO 2 and Total Suspended Solids (TSP) and NO 2 values within the
Nigerian Ambient Air Quality and WHO standards.
Geology and Soils
The Study Area is located within the Niger-Delta Basin and Benin formation,
characterised by deposits laid during the tertiary and cretaceous periods (Alile et
al, 2007). The Benin Formation has been created from weathered sedimentary
rock (Ogunkule et al, 1980). This mixture of sediment demonstrates a highly
permeable sand aquifer system with multilayer aquifer characteristics. The
Study Area falls into the southern belt of forest soils and red-yellow ferrasol on
loose sandy sediments. Soils comprise a mixture of sand, silt and clay with a
predominance of sand and hence can be defined as sandy loam (Royal
Horticultural Society, 2011 and NIPP, 2010).
A soil survey was undertaken during the wet and dry season to characterise the
soil’s baseline physico-chemical characteristics and determine any existing
contamination. Soil quality was generally found to be good across the Project
site, with low levels of heavy metals and hydrocarbons (with one exception at
the western-most portion of the Project site).
Water Resources
No streams or rivers were identified on the Project site and the closest water
resource is a small non-perennial pond located approximately 800 m to the north
of the site boundary. The Ikpoba River, into which the pond drains, lies
approximately 4 km east from the proposed site.
Two boreholes are located in the area surrounding the Project site, at Ihovbor-
Evboeka and Orior-Osemwende. Water samples from these boreholes were
tested during the wet and dry seasons and water quality ranged between good to
generally good, although the pH lies outside of the WHO and FMEnv optimal
ranges for potable water. Nitrogen levels at Ihovbor-Evboeka were higher than
FMEnv levels (but within WHO limits) during the dry season. Similarly for
Nickel concentrations during both seasons. Water quality from these boreholes
is considered to be fair.
Noise
A survey of the ambient noise levels on the site was undertaken during the wet
and dry seasons. Noise levels measured were higher than expected for the semirural
environment, likely due to short-term construction noise from the
neighbouring site and rainfall at the time of measurement. The true baseline
measurement was therefore not possible. The average overall for the NIPP site
and surrounds (prior to NIPP construction activities) was measured at 34 dB (A)
during wet season and 37 dB (A) during the dry season. As with standard
methodology, the baseline noise levels are therefore considered to be below the
AZURA EDO IPP
XIII
DRAFT EIA REPORT