Environmental Engineering Reference
In-Depth Information
Exploration and Production Licence (PEDL) was granted in September 2008.
(A PEDL is awarded for six years initially on the basis of the applicant
demonstrating technical and financial competence and an awareness of the
environmental issues. The licensee is also required to demonstrate that they
have obtained access rights from relevant landowners and complied with
other statutory planning laws).
Work commenced on site, drilling the first test well in August 2010 at
Preese Hall Farm followed by a second at Grange Hill Farm later that same
year. Work on the third, near the village of Banks, commenced in August
2011. Based on the initial exploration, Cuadrilla Resources announced its
first estimate of the volume of shale gas within its licence area on 21
st
September 2011. It estimates the total gas initially in place to be 5660 billion
cubic metres (bcm) of gas; if it were able to extract 20% of the gas this would
equate to 1132 bcm of recoverable gas.
Island Gas Limited (IGL) and its subsidiary company IGas Resources PLC
operate in the North of England and North Wales and, using borehole logs,
they have identified shale deposits extending over 1195 km
2
with an average
depth of 250 m. In October 2010 they gave estimates of gas initially in place
as between 2.5 bcm and 131 bcm, with a risk factor of 50% for their North
Wales licence area. No estimates of recoverable gas have been given and they
intend to conduct further exploratory work in the future to fully understand
the potential of these deposits.
35
Eden Energy Ltd commissioned an independent expert report from RPS
Group plc, a multinational energy resources and environmental consultancy
company, in respect of prospective gas reserves in the 806 km
2
of the seven
PEDLs in South Wales. They have estimated that the proven reserves of gas
initially in place are 968 bcm, with recoverable volume of 362 bcm.
Dart Energy, which took over Composite Energy in 2011, has indicated
shale potential in addition to coal-bed methane extraction within its licence
area of north west England and Wales with an estimate of total gas initially
in place of 34 bcm.
36
In April 2012, Dart Energy completed the acquisition of Greenpark Ener-
gy's 17 UK licences. Of these licences, PEDL159 is the furthest developed and
is situated in Scotland. Eight wells were drilled in the area by Greenpark
Energy, with three of these wells being pilot production wells, which dem-
onstrated good production rates of natural gas from the coal seams. The
remaining five wells were exploration wells; these delineated seam thick-
ness, gas contents, gas saturations and permeability trends in the area. Since
the acquisition, Dart Energy has been assessing the licence area from both a
sub-surface and surface perspective.
In total, Dart Energy now have four licences in Scotland and a further 28
licences in rest of the UK.
Shale gas production in the UK is still some years off, with production
unlikely to start before 2015-2016. Estimates of production are still very
dicult to obtain, but Cuadrilla have estimated that commercial develop-
ment of the resource would provide an annual average of 0.7 to 2.8 bcm of
