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

13.21 A Coal Authority Mining Report for the site identifies that the study area is
within the likely zone of influence on the surface from workings in seven
seams of coal at depths of between 230m and 820m. The last date of
working is given as 1987 and therefore any ground movement from the
workings should have ceased. There are no mine entries shown within the
site boundary.
13.22 The Coal Authority has not received a damage notice or claim for the
property since 1 January 1984.
TOPOGRAPHY
13.23 The study area occupies an area of hilly topography with elevations
ranging from 65m to 110m above Ordnance Datum (OD).
ASSESSMENT OF EFFECTS
GROUND CONDITIONS
13.24 The possible presence of sandy or gravelly alluvium along the floors of the
two stream courses described above, in combination with the
characteristic steep valley sides of the site, could cause local instability in
the form of minor land slippage or soil creep. However features formed by
such processes were not observed during previous surveys.
13.25 Head deposits are commonly present on slopes or on the floors of valleys
although they have not been indicated on the geological plan. They are
variable in composition and are typically poorly stratified and poorly sorted.
They may contain shear planes, which can be reactivated when undercut
by excavations.
13.26 A characteristic of the Upper Pennine Middle Coal measures mudstone is
that they commonly weather to a sticky, yellow brown clay, which may
exhibit shrink swell properties due to changes in soil moisture contents
which can potentially cause structural damage.
13.27 Faults have been mapped across the site as described above. The
geological faults within this area are of ancient origin and are today mainly
inactive. However they must still be regarded as planes of weakness
whereby mining induced subsidence and severe subsidence effects may
commonly be concentrated along them. The depths of previous old mine
workings and the absence of damage notices or claims since 1984 within
the scoping boundary indicate future ground movements are very unlikely.
FLOOD RISK ASSESSMENT
13.28 PPS25 suggests that consideration should be given to site vulnerability to
other potential sources of flooding including:
Flooding from groundwater;
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Penny Hill Wind Farm
Environmental Statement