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The Dig Log
After being completely flooded for the whole of the Winter, water levels in the dig started to fall
in March. The dig was visited
on 10th March and the water was about 3 inches below rail track level.
The dig was visited again on the weekend of 17th/18th March and the water level
was below the cross-rift!
Saturday 24th March
Brickworks Dig Latest - A breakthrough!
The water level was lower still than the previous weekend, but it was not
possible to get through to the dig face as the floor was covered in a thick
layer of quicksand. During the day we:
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cleared out the
infill which had slumped in from the cross-rift during the water floods,
- installed conveyer belt in the
main dig passage,
- surveyed the system down the the cross-rift and
- broke through into approximately 15 feet
of virgin passage!
The new passage was accessed at roof level in the right-hand side
of the cross-rift. It only took about 15 minutes to dig a space wide
enough to squeeze through. This is a very interesting area.
Immediately ahead at the breakthrough point is a sand choked passage but with a
couple of inches of air space at roof level. To the right is another rift
passage. This is too tight to the right and is choked after a short
distance to the left with a boulder collapse. Before this there is a
pebble choked depression in the floor which seems to be water washed. The
passage ahead at the breakthrough point will probably connect with this and may
be worth digging.
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The conveyer belt laid out on the surface, ready
to go underground. |
The breakthrough point in the roof of the
cross-rift |
The dig team: KeEd, BrMa & DeRo
Weekend 14th/15th April
A busy weekend. On the Saturday we replaced two of the
wheels on the truck, pumped out the cave, removed the stacked bags from the
cross-rift, started to permanently install the yellow pipes, placed cup-hooks
down the main passage to hold up the cables and started to dig a 'sump pool'
below the cross-rift. We did experiment with pumping the water from the
lower section up into the right-hand side of the cross-rift but it immediately
poured back down, proving that this is not a way on. We also moved 68 bags
of infill to surface.
On the Sunday we completed the installation of pipes and cup-hooks and continued
to dig the sump pool. At one point we have dug down to the cave floor
which has a vadose slot in the floor approximately one foot wide. Another
60 or so bags were moved to surface and another 40 bags are stacked at the
bottom of the main railway track. The cave is no longer but is
significantly deeper.
At the dig face there is no significant passage to the left - just a small roof
tube. Straight ahead the passage again closes down below the roof tube,
but we can see the top of an arch just above the infill, so this is the way on.
The dig team: KeEd, AnGr (Sat only), BrMa,
GrSm, JoSm & ChWe
Weekend 15th/16th September
The Dig Team - Sunday 16th September 2007
Left to Right - Chris Webb, Keith Edwards (rear), Heather Simpson, Derek
Robertson, John Smith |
Another very busy and successful weekend. The water was a
couple of feet below the cross-rift so we set up the pumps and while the water
was being pumped out we pulled out the sandbags that we had left stacked at the
bottom of the railway track and in the cross-rift. We then filled about
another 80 sand bags and moved them to the bottom of the railway track.
The in-fill was taken from the floor of the cave in front of the dig face.
On the Sunday we firstly pulled out the previous day's sandbags. We were
then in a position to start back-filling some of the passage. We have
removed the railway track from the main sump pool and partially filled it in.
The intention is to fill this in completely and put conveyer belt down. We
have also back-filled the extension passage below the cross-rift to form a
downward slope which now has conveyer belt on top.
The dig is now about 3 feet longer - we have begun to dig out below the arch
that we discovered last time. It is also a few feet deeper. The
infill at roof level is hard packed sand (like concrete to dig) but lower down
there are layers of sand, grit, shale and clay which is very loosely packed and
some of the easiest digging we have ever encountered. We have undermined
approximately another 3 feet of this and are hoping it will have collapsed by
the time we return.
The dig team: KeEd, BrMa,
DeRo, HeSi (Sun only), JoSm & ChWe + Piers from SWCC (Sat only)
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