Enabling works for a quarry silt tip extension located on a peninsula of the Scottish West Coast just above Oban. All personnel had to access the site by motor launch and plant was transported by barge from the mainland Rhugh Garbh depot.
Peat was stripped from above rock excavation areas and below the footprint of the rock retaining bunds to use as a restoration medium on the existing silt tip.
Rock was blasted from excavation areas, placed to form retaining bunds for the extension to the existing silt tip and also to form a new silt settlement lagoon retaining bund. The construction of the silt settlement lagoon bund incorporated a bentofix liner and the construction of a concrete overflow weir and associated water measurement apparatus.
Two new attenuation lagoons were constructed including a concrete flow measurement channel. These lagoons were connected by 450mm pipework placed in a deep channel, which was blasted and the rock hauled to locations as above. Insertion of penstocks and flow valves regulated the flow between the attenuation lagoons.
Existing water and electrical services were diverted around the works in a 2m wide trench for a distance of approximately 3km. Additional services were laid in the trench to meet the new works at the silt settlement lagoon.
A new substation and access road to the silt settlement lagoon was also constructed together with other small drainage works.