31. By 1960, 1500 miles of underground workings were in the Kirkland Lake camp and 12 miles of direct hoisting shafts. 32. The quarry prospered for a while, but then profitability declined, and in 1900, a large section of the underground workings collapsed. 33. It has been mined on a small scale in the past and the underground workings have proved to be valuable drill sites. 34. Underground production at Maenofferen ceased during November 1999 and with it the end of large-scale underground working for slate in north Wales. 35. The new find is located about two kilometers south-east of the Darlot mine and 1.2 kilometers from the existing Darlot underground workings . 36. Based on a review of the data there is no evidence of underground workings along the proposed line or at tower bases. 37. Kempe and Matthews developed the underground workings , and Kellow recommended that ?5, 000 of the capital should be used for this purpose. 38. Development work started in 1986, but along with the residual Cynheidre underground workings , closed in January 1989 while employing 1, 043 men. 39. Students from the School of Engineering were largely responsible for the renovation of the underground workings that were made safe for tourists. 40. There is no access to the underground workings within the museum, but a simulated gallery provides full accessibility for blind and disabled visitors.
