Underground Facilities

1
The Boulby Underground Laboratory for Dark
Matter Research
Boulby Mine
Surface Facilities
Many of the surface facilities required for dark
matter research at Boulby are supplied by
Cleveland Potash Ltd. This includes emergency
medical support and facilities, chemical
laboratory and clean room facilities and surface
transportation.
Lamps
Medical Centre
Boulby mine is a working potash mine situated on
the North East coast of England, a few miles
north of the town of Whitby in the North York
Moors. The mine is run by Cleveland Potash
Limited (CPL) and at between 850m 1350m deep it
is the deepest mine in Great Britain.
Fork-Lift
Chemical lab
In 2000 Joint Infrastructure Fund (JIF) funding
was secured to build a new purpose-built surface
facility at Boulby, Now complete, the John
Barton building provides space for storage and
staging of underground experiments, office and
laboratory space, computing and mechanical
workshop facilities and washing and cooking
facilities for staff and visitors.
Map of excavations
There is a huge underground network of caverns
and roadways at Boulby. Since mining began at
Boulby in 1968 over 1000 kms of tunnels have been
excavated and using remotely controlled
heliminers around 50 kms of new tunnels are cut
each year. Excavations currently stretch
approximately 5kms south and 8 kms north - beyond
the coast and under the North Sea.
The John Barton surface building
Staithes - near Boulby
Underground Facilities
Background Radiation
The underground research facilities have evolved
since dark matter studies began at Boulby. There
are now 3 main research areas, each approximately
1km from the mine shaft, giving a total floor
area of gt1500m2. All of the laboratories have
telephone and internet connection to the outside
world and all are fully stocked with the tools
and instrumentation required to run and maintain
the experiments they house. The ambient
temperature in the mine is commonly 30C or
higher - so air conditioning is used to keep
working temperatures to a tolerable working
level.
A deep underground site is essential for Dark
Matter detection experiments as the large amount
of overhead material acts as a shield to highly
penetrating cosmic ray particles which would
otherwise dominate and obscure results . At 1100m
below ground at Boulby mine the cosmic ray muon
flux is a factor of 106 times smaller than at
sea level - which ranks Boulby alongside just a
handle of world-class underground research sites
around the world.
Dark Matter research areas
The new JIF area
Geology
The Boulby facility has the further advantage
that the potash and rock-salt layer in which
caverns and roadways are excavated has relatively
low levels of Uranium Thorium. These are
commonly occurring elements which result in the
production of radioactive radon gas and the
emission of neutron and gamma background
radiation. The reduction or elimination of all
sources of background radiation is an important
requirement in all dark matter detection
experiments.
All of the research areas consist of wooden
framed structures built within specially
excavated caverns in the rock salt. The largest
and most recent area is the gt1000m2 JIF area
supported by the Joint Infrastructure Fund.
Recently completed and waiting to be filled, the
JIF area will house the next generation of dark
matter detectors planned by the UK Dark Matter
Collaboration.
Summary of Backgrounds