At that time, of the tunnel had been excavated, out of a total of . From sums of money paid to Cail, it would appear that he was employing 200 to 300 men on the contract, and the tunnelling progressed well, although there were difficulties at both ends, where the limestone was particularly hard. The tunnel was completed by 31 December 1859, thirteen months after Cail took over the contract. Shortly afterwards, much of the plant used on the project was put up for sale, including nine steam engines, 60 tons of bridge rails, 14 sets of pumps and two brick and tile making machines. The land at Tongues Farm, where the brickworks had been operating, was returned to agricultural use. Many of the workmen had lived in huts in this remote area, and those were demolished. Most of the shafts were arched over and filled in. The main fault identified was a step at the western end, resulting in water standing to a depth of , which Cail claimed was due to inaccurate drawings.