environmental statement - Rotherham's Online Application for ...

13.6 The FRA has been based on a detailed review of existing hydrological
information and new hydrological analysis. More specifically the study has
incorporated the results of:
A walkover hydrological site survey;
Flood Estimation Handbook (FEH) rainfall runoff analysis;
Existing drainage modelling review; and
Hydrological calculations to estimate the potential impact of the
development on flood risk.
BASELINE INFORMATION
GEOLOGY
13.7 The geology of the study area has been assessed by reference to the
BGS Sheets detailed above. The sites eastern margin predominantly lies
along the foot of the M1 motorway embankment. Apart from any made or
landscaped ground associated with this embankment there is very little
indication of previous development, other than around Penny Hill
farmhouse and Ulley Beeches.
13.8 No superficial deposits are shown on the geological map although there
may be limited tracts of alluvium along the two stream courses that run
within the site boundary (described within the hydrology section below).
13.9 Bedrock is mapped at an outcrop across the whole site and it is likely that
rockhead is within one metre of the surface beneath any unmapped
superficial deposits or artificial ground. The study area is situated primarily
on the Upper Pennine Middle Coal measures of carboniferous age. This
strata consists of grey mudstones and siltstones with common beds of
coal and locally thick beds of sandstone. The sequence is in excess of
500m thick.
13.10 The sandstone exposed across the site represents Mexborough Rock, a
yellow-brown, medium-fine grained sandstone. This unit is estimated to
be about 70m thick in this area and lies approximately at 40-80m beneath
the higher ground in the central and eastern parts of the site. The outcrop
of Mexborough Rock to the south-west which is brought about via a fault
(see below) is estimated to be 4 - 7m in thickness. The beds of sandstone
to the east of the site are also thin with estimated thicknesses of between
1 - 5m. These sandstones commonly give rise to bench-like features on
the ground, and are also revealed by a change in soil conditions, from clay
soils to sandy soils strewn with sandy fragments.
13.11 The Carboniferous strata generally dip towards the north-east at angles
between 5 – 10 degrees. In the presence of faults these dips are variable
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Penny Hill Wind Farm
Environmental Statement