It was driving a tunnel to from the Perseverance Mine on the Leigh, more than 6 miles to one of two feasible points about a mile and a half below the Leigh Grand Junction Bridge, to be funded by the government at a cost of 38,000 (and more to the north privately - there were many variations on the theme). It was designed to drain the Sebastopol Plateau and the Durham Lead.
Some felt the pumps would not provide adequate drainage, others suggested that the costs were underestimated, others that a far more extensive project would be required to do the job, others suggested that the returns of gold would be much lower than expected , and others that the leads might not be there as expected and that there would be little gold left.
We now know that the gainsayers were probably correct, that the geology was misinterpreted and that little gold could be expected (the leads are now known to have flowed north under the basalt, not south, and that the apparent southwards direction was because a much later river from the south cut its headwaters northwards into the old lead system (it was affected by uplift on the Enfield Fault), giving a younger system that drained south but with little gold (because most of the gold went north earlier, and because the younger south-flowing system cut a deep gorge in which little gold-rich gravel could accumulate - this was actually mined later but little gold was found).
