OUCC Proceedings 13 (1991)

 In May 1991 Jenny Vernon, Gavin Lowe and Tim Guilford entered a mine shaft by squeezing through an access cover located in front of the kitchen window of Ore's Close Farm, Hillgrove. The shaft, which had been pointed out to us by the resident of the farm, had been looked at previously by Tony Seddon and Pauline Rigby, who had descended to about 50ft, so this time we took four ladders and belayed to a stout block and metal stake braced across the entrance. An initially vertical pitch becomes inclined and muddy to a depth of about 100ft, ending in downward muddy grovels to a boulder-strewn crawl. The open 45° slope (area excavated for ore) beyond is the first safe place to wait away from falling rocks whilst members of the party are in the entrance. Perhaps 100ft of workings extend horizontally and upwards in several places, but the way on proved to be up the first incline past a hideously precarious wall of infill on the right. Here we dug through a vertical boulder choke into an incredibly muddy 50ft inclined tube. This squeeze is not only difficult, but two rock falls have now made it extremely dangerous, despite one attempt at shoring it up. A second choke was then dug through and led immediately out over a 50ft pitch. The gallery appeared to continue on the opposite wall, but was back-filled. Since the choke had also been back-filled, it seems that the shaft must have been abandoned from below, suggesting, though not proving, the existence of another entrance to the mine. The shaft was free-climbed down for about 35ft, past one parallel but infilled gallery, when further progress appeared too difficult. From this point a gallery could be seen clearly extending in two directions from the base of the shaft. We determined to return with a bolting kit.

On 25th May 1991 the original three returned with Chris Densham, bolted the pitch head and continued exploring from the previous limit. The less obvious route leads via a flat-out crawl down into a mined rift which continues unexplored. The more obvious route leads easily to a junction where to the right a wide tube upslope chokes with mud and debris after about 30ft. Left, the main route continues until a dangerous right turn under chocked boulders leads to a stretch of passage marked by rotten wood shorings and small rock falls. Another upslope sandy passage leads into higher level workings where ore seams can be seen. The main passage leads eventually past an opening up on the left, down a boulder slope, flat out under boulders, then up a steep slope to the left. The passage ends in a short drop into an abandoned face where bore holes are much in evidence.

Back at the base of the boulder slope a way down was dug through a boulder choke into further workings at a lower level. A large inclined rift chamber leading only to face workings is passed on the left, and the passage ends in a choke immediately beyond a left turn into a sumped passage - perhaps the mine's deepest point so far.

Back at the opening on the left in the main passage, a short sandy crawl meets a large fallen boulder which was squeezed underneath into a narrow inclined rift full of mud. This opened out into walking or stooping passage, interspersed with short crawls, to a much larger rift chamber. The chamber was traversed on chocked debris false floors to a point where the walls were too wide to bridge, and the way on would have involved climbing down to the base of the chamber. No limit was found, but the dimensions of the chamber and quantity of mining activity suggest that this part of the mine must have been worked from another direction. It seemed unlikely that our entrance route would have been used extensively. In all about 500m of new passages were explored.

Progress out was slow because of the need to exercise caution at various danger points. Particularly worrying is the loose wall near the entrance, part of which fell on Jenny's legs as she was negotiating the backwards manoeuvres required on the way out. Even people with normal length legs will find it difficult not to destabilise the fall in future, and we can only recommend that no attempt is made to pass this obstacle again unless a serious effort is made to shore the whole section up satisfactorily.

The MNRC report on 'Orrs Close, Hillgrove' (1938, pp 50-51, obtained from the curator of Wells Museum) describes a 55ft entrance shaft and workings on three levels. The Caves of Mendip (Nicholas Barrington, 1964, Dalesman Publishing Co., Clapham) mentions Ore's Close as 30ft deep, containing natural cavities, and blocked in 1955. Both reports believe Ore's Close to be one of the biggest lead mines on Mendip, if not the largest. However, the present shaft is nearer 100ft deep, and the system is far more extensive. It is likely that the entrance series has been explored before, but beyond the dug chokes previous exploration seems unlikely.

Entering this system disturbs the privacy of the residents of Ore's Close Farm, Rhonda and Mark Cottle, and it is only through their kind cooperation that we have been able to explore here at all. Only members of OUCC are allowed down, and then only with explicit permission in advance. As with Dallimore's, park on the main road, not at the farm.

Tim Guilford