Table 3: Geotechnical stability checks.

Sengio areaCiana-Tane Pilastretto areaBraghini area
Slope face within 290–350 m (sliding surfaces characterising the contact between debris and basement)Slope face within 260–350 m (sliding surfaces characterising the contact between debris and basement)General stability of the quarrying face (sliding surfaces passing through a point)Local stability of the quarrying face (sliding surfaces passing through a pointSlope face within 590–680 m (sliding surfaces characterising the contact between debris and basement)Slope face within 540–585 m (sliding surfaces characterising the contact between debris and basement)

Fs (December 2004)1.25–1.371.28–1.301.39–1.591.52–1.831.111.21–1.34
Fs (Evolution within 5 years, December 2009)1.33–1.671.36–1.41(1)2.27–3>31.45–1.861.32–2.01
Fs (Evolution within 10 years, December 2014)> 2.10–3(2)1.7–1.95(3)2.04–3

(1)Circular surfaces tangent to the contact: rock basement-debris
(2)Slope face within 265–290 m (sliding surfaces characterising the contact between debris and basement)
(3)Slope face within 235–290 m (sliding surfaces characterising the contact between debris and basement).