PROTECT TO CONSERVE

Following the modification of the M-50 project, which prevented the destruction of the larger part of the shafts at Casa Montero, the site needed to be covered to afford it protection. The excavated shafts were filled with expanded clay, which offers a number of advantages over other types of filler:

• its low density reduces overloading
• it is an autocompactable material, which prevents compression and damage to archaeological remains
• it is poorly compressible; no settling occurs after shaft filling
• it has drainage capacity
• it provides a natural thermoinsulation and protects against frost
• it is inert and incorruptible; it does not deteriorate over time, and prevents the growth of plants and fungi
• it is recoverable and 100% recyclable
• it can be put in place and removed via a mechanical pump, facilitating both processes
• it can protect archaeological remains from fire

 

The expanded clay ARLITA G-3 (grain size 6-16 mm; absorption capacity 23+3%) was chosen for the job. This surface of the shafts was then covered in geotextile to prevent plants taking hold over the clay; this impeded any root growth into the shaft interiors.
Finally, the plant cover was restored over the conserved area.  The replaced substrate was about 0.70 to 1.15 m thick to avoid possible damage from vehicles or machinery.