20th March 1977
Divers: R.J. Shackleton and J.T. Griffiths

Previous exploration: NLS.15:6, 16:18, 38:17, and 41:27.

Aim: To replace some of the light line with more permanent thick line and to completely re-survey the route.

R.J.S. did the surveying whilst J.T.G. laid 90 m. of new line from the beginning of the sump. Beyond the junction with the line to the left laid by O.W.S. (NL.41:27), my line had come badly adrift and so the survey was terminated at this point.

11th June, 1977
Diver: R.J. Shackleton

Aim: to locate the dowstream continuation. Three small static sump continuations to the right of the passage between the main lake and the entrance were explored in a dowstream direction and all were found to be too low. The right hand wall from the start of the main sump was searched for 200 ft. with no result, although the first 100 ft. or so was bordered by a low bedding of uncomfortable height. The left hand wall of the main sump was also searched with simlar lack of success. It would seem that the downstream continuation lies down the wide low bedding to the right of the entrance, and is too immature to be comfortably followed. The possibility of something being missed on the search cannot be ruled out however, as the main route is large.

R.J.S.