Poor Visibility by Chris Grimmett
Poor Visibility by Chris Grimmett
The weather played the usual tricks and as soon as the AGM had finished it commenced raining.
Sunday was a washout but Monday, still drizzling, saw Simon Amatt and Graham Christian motoring up to the dig - carrying the newly 'breathed upon' winch and gear, whilst Andy Amatt, Chris Grimmett and Clark Friend took a more leisurely route up on foot.
40 Grimmett buckets of water were removed via the Penwyllt python (about 15 metres of corrugated hose attached to the screw lid of a 5 gallon flask with the bottom removed) before digging commenced. The floor of the aven has been lowered by some 3 feet and there appears to be the start of an arch in the western side. The eastern side is now entirely filled with easily removed sand set amongst the odd boulder.
Because of the wet weather and the stirred up fine sediment in the bottom of the dig, it was not possible to reach some undisturbed (dryish) ground in an attempt to persuade the water to disappear through the floor. However, there still appears to be some natural drainage as the water level seems to be always at a maximum of about 3 feet.
Given the general dip of the formations in this region - about 13°, that the base of the Carboniferous Limestone is at c. 460m, that the dig is at c. 500m and some 180 m horizontally away from the position of the boundary, the vertical depth of limestone under the dig is some 81.6 m. As we are down about 35 feet, just over 10 m, there is still great potential!
Next assault is the Spring Bank holiday (Kitchen/Dining room and weather willing) - watch this space for details.