With Nick, Duncan, Brockers, Jake, Jon, and Tav

Jake and Tav digging in the deep Soft South, Jon on the ledge, Brockers at the junction and Duncan at the bottom on the entrance, at least I think that was the order. Me and Nick were on the surface. We hauled bags and rocks up out of the cave, added more rocks to level up the terrace wall and create space for spoil, Nick dug some steps and, in general, it was a chilled-out session for us.

The terraced spoil heap.

93 filled bags were emptied onto the spoil heap and all rocks incorporated into the terrace walling. There was some question as to where the other pack of bags had gone as we were expecting 100+ to arrive on the surface. It turned out that someone had a comfy seat and was not prepared to offer it forward when the diggers had run out of empties!

An estimated value for the volume of the ‘pot’ in the Soft South.

Using the equation: V = πr2 h, and estimated values, 4 metres diameter (2m radius) and 5m height, an estimated volume = 62.83185m3  is calculated:

π = 3.14

3.14 x (2×2) x 5 = 62.83185

Assuming the density of limestone is about 2.6 – 2.7 tonnes/m3 and the density of clay soil about 2.0 – 2.3 tonnes/m3 and using the estimated volume of 62.83m3,  a range for the quantity of sediment removed can be deduced.

Using the lower density values above, for limestone 2.6 x 62.83 = 163.4 and for clay soil 2 x 62.83 = 125.7, a range between 125 tonnes and 163 tonnes of sediment has been removed from the pot in the Soft South since December 2020. This is likely to be an underestimation.