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rections. The infrastructure, which currently
supports average daily traffic of about
24,000 vehicles, 30% of which is heavy
vehicle traffic, is expected to be used by
some 57,000 vehicles by the year 2030.
lntegration with the environment
Environmental measures included the
restoration of the southbound carria-
geway between kilometric markers 252.3
and 256.7. This restoration consisted pri-
marily of recovering the tributaries of the
Arroyo del Rey and restoring the topo-
graphy that had existed prior to the work
done in the year 1984.
To do so, the current embankments
were cleared and the clearings were fi-
lled in, leaving a 5-metre wide forest trail
running through the centre of the filled in
area. This will ultimately be replanted with
the characteristic trees and shrubs of
each one of the habitats being restored.
A series of measures was also imple-
mented to reduce and correct the en-
vironmental impact of the work, which
included: improving permeability for fau-
na by eliminating one of the existing ca-
rriageways and increasing passageways;
cleaning and restoring river beds and
banks; improving the habitat conditions
of rabbits and lynx; recovery of the en-
demic centaurea citricolor; repopulation
and selective pruning for fire prevention
purposes; integration of the tunnel ope-
nings into the natural landscape; restora-
tion of the landscape in all affected areas;
protection against noise pollution and
protection of archaeological heritage.
Approximately 8 million Euro were spent
in these measures
The Minister of Public Works visits the Pajares tunnels built by FCC
Ana Pastor, Minister of Public Works,
visited the worksite of the Pajares two-
track tunnels built by FCC in a joint ven-
ture with Acciona, which are part of the
new Leon-Asturias high speed railway
line. The project managers, led by FCC
Construcción’s chairman, José Mayor
Oreja, described to the minister and
other members of the Ministry, the cha-
racteristics of the tunnel layout.
The work site that they visited is part of
the La Robla-Pola de Lena section bet-
ween León and Asturias and represents
an improvement over the current Pajares
railway platform. The overall budget for
the project is more than 2.05 billion Euro
of which (about 1.65 billion) relate to dri-
lling work in the Pajares mountain range.
The group visited the Pajares section which
runs parallel to the Huerna River and the
A-66 motorway down to the San Blas ra-
vine. Because of the rugged terrain in this
area, the section is divided alternately into
a tunnel (Los Pontones) and a viaduct (San
Blas).
The Pontones tunnels run parallel between
the towns of Pontones and Sotiello, in within
the municipal district of Pola de Lena. Mea-
suring 6 kilometres in both directions, pro-
vide passage through the Cordillera Cantá-
brica and, when the work is completed, the
route will be shortened from the current 83
to 50 kilometres. The new layout replaces
the one built in the second half of the 19th
century, an engineering feat at that time.
The tunnels are two parallel tubes 24.9
kilometres long apiece and are therefore
the sixth-longest tunnels in Europe and
the seventh-longest in the world. Their in-
ner diameter is 8.50 metres, and they are
designed for speeds of over 250 km/h.
Five tunnel-boring machines participated
in the excavation work, which was a great
engineering challenge.
The tunnel’s execution was divided into
four lots. FCC did the first section, which
included execution from the southern
mouth of the tunnels between La Pola
de Gordón and the district of Folledo.
The first 7.9 kilometres were bored with
two TBMs, and the remaining 2.5 kilo-
metres were handled using conventional
methods.
San Blas Viaduct
The intersection of the new León-Asturias
high-speed railway line at the San Blas
stream, in the Pajares-Sotiello section,
made it necessary to build two separate
viaducts (one for each section). The right
and left hand viaducts span over 130 and
126 meters, respectively, with a 30 metre
separation between the railway platforms.