Light at the end of the tunnel

Materials World magazine
4 Mar 2012

It is not often that grand theft is of interest to readers of Materials World, but news last month concerning the work of thieves who dug a 30-metre-long tunnel under a car park and up to a store in Manchester in order to get to a cash machine may have caught your attention.

In scenes reminiscent of the Great Escape meets the Great Train Robbery, the amateur miners had to cut through almost 40cm of concrete to get to the money. The passageway, a single passage adit mine with the entrance located halfway up a railway embankment, was just over a metre tall and had been fitted with lighting and roof supports. Police estimated it had taken six months to construct but gave few other details of interest to IOM3 members. For instance, was the adit augered, excavated or hand dug? Was the roof bolted or just propped, and what type of roof support works best under variable traffic loading?

Had HM Inspectorate of Mines been notified with respect to Regulations 7 and 34 of the MASHAM Regs (1993)? Did they comply with Regulation 18 of the Electricity at Work Regulations (1989) that requires the mine manager to submit a copy of the ventilation plan showing the location of the equipment and a copy of a schematic diagram of the equipment? If not, then they could find themselves being prosecuted for more than just bank theft. I doubt they completed an Environmental Impact Assessment, given the relatively low spoil volumes, and probably felt that a Site Restoration Stakeholder Engagement Plan was unnecessary, although it might have bought them a bit more time before discovery.

I also wonder whether such a project was economically viable. Let’s say the tunnel party comprised four people – foreman, digger, propsetter and bearer. To avoid detection let’s assume they only worked a 12 hour night shift, for a five day week. That still amounts to more than 5,000 hours, at foreman rates of £25/hr and £15/hr for the others, I make that around £87,000 just for the labour. The police did not reveal how much cash was in the machine – the theft was discovered on 2 January, so presumably not very much with the heavy Christmas demand. I can’t help thinking that such effort and enterprise would have been better rewarded in more legitimate endeavours.

I notice that the IOM3 Shaft Design and Construction conference is coming up in April and I wonder if they are still accepting abstracts? If so, our amateur tunnellers might like to submit a paper on noise abatement procedures for urban tunnelling. I’m sure there are many in the mining fraternity who would like to know how it was done (for purely professional reasons, of course). I wonder if they can organise a video link from HMP Strangeways?