The Intricacies Of Restricted Access Drilling

by | May 27, 2020

When most people think of geotechnical drilling companies, they don’t think of an urban setting. But here’s the thing, we do. Restricted access drilling is now a rock-solid option when it comes to those environments where a regular rig won’t work. Towns and cities are of course where the mind jumps to when thinking of sites with restricted access, however this form of drilling is also often used in more rural settings as well. Anywhere that presents a difficulty in accessing, the chances are, you’ll opt for a more specialist, restricted access rig.

The team here at Borehole Solutions, one of the UK’s leading geotechnical drilling companies, has put together this blog to talk about the things to consider when looking at a restricted access site.


The Applications Of Restricted Access Drilling

What can you do then with restricted access drilling? It turns out quite a lot! The applications of these rigs include but are not limited to:

  • The installation of retrofit geo-exchange units
  • Cable percussion drilling
  • Micro-piling
  • Open borehole sampling
  • Ground anchors and soil nails
  • Window sampling
  • Hollow stem augering
  • Water wells

The versatility of these more portable, smaller rigs makes them attractive additions to any drilling company’s rig fleet.


Urban Settings

Let’s start with the obvious ones – how do you go about drilling in a town or city where you’ve only got a few square metres to work with? How could you possibly drill in underground transport tunnels, hotel lobbies or in the middle of traffic? Well, it’s much more feasible than you think. The portable nature of most restricted access drilling rigs makes getting to the desired drilling spot. If the rig is still too big, it can be dismantled and reassembled on-site to complete the job. This form of modular drilling is particularly useful in these urban settings where space comes at a premium, both in terms of access and the site itself. Where the issue presented is width, a narrow alleyway for instance, many mounted rigs now have width-adjustable capabilities so that they can move seamlessly through areas that would have previously been unthinkable.


Watch Your Head!

Narrow spaces equate to restricted access, as do densely packed environments (both rural and urban) present restricted access. A form of restriction that people often forget, however, is height restrictions. Conventional rigs are no small pieces of equipment. Site investigations are often carried out as preliminary work for potential larger developments. Before any clearing or more serious construction work takes place, however, the appropriateness of the ground has to be checked. This may mean accessing a clearing in a forest with a low-hanging canopy, or perhaps drilling near the foundations of civil engineering works like bridges. It may perhaps even just be a building with not very much headroom!

We possess restricted access drilling rigs, capable of drilling with only a couple of metres of headroom thanks to telescopic masts, for those areas that make you stoop down! So, whatever the limiting situation happens to be, these rigs can work with them.


Watch Your Feet!

Looking at a different example, you may have a wide-open field that, ostensibly at least, presents you with no restricted access problems. Sorted right? Not quite. The particular environmental features of certain drilling sites mean that a smaller rig becomes the only option. Where there are rare flora and fauna, or particularly threatened species, it’s crucial to minimise your rig’s footprint where possible. This means both its physical and its carbon footprint. Whilst there’ll invariably be some disturbance with any site investigation, using these portable and modular rigs means you can a) get to the site itself whilst causing less damage and b) have a more minimal impact on said patch of ground that you need to investigate. Drilling companies such as ours are as environmentally conscious as they’ve ever been, and our restricted access drilling rigs form part of that thinking.


Restricted Isn’t The Same As Limited

This is something that people often get mixed up. Restricted access drilling is not the same as limited access drilling. As we referenced in the introduction, restricted access refers to getting the rig to the site in the first place. Limited access on the other hand, is where the drilling space itself impedes your ability to work with regular equipment and under normal circumstances. A very confined space, for example. Fortunately, companies that offer restricted access drilling will usually also be equipped to deal with limited access situations as well. A prime example of limited access drilling is the use of an external generator or power unit for your rig that’s housed externally from the site itself, and is connected by hosing, reducing the amount of equipment needed on the site itself.


Safety’s Just As Important As Ever

If anything, in restricted access sites where you’re working in tighter confines or more difficult areas to access, safety becomes doubly important for those working on site. To combat this risk of personal injury, most restricted access rigs are fitted out with hydraulic breakout clamps. These mitigate the need for those operating the rig to get too hands-on with the rig’s operation. This is vital in these cramped conditions. The general public also becomes a much greater factor to consider in restricted situations.

In towns and cities it is the responsibility of the drilling company to ensure that sufficient parameters are set up so that there’s absolutely no risk of any member of the public coming into contact with dangerous machinery. Safety standards have come on leaps and bounds but the heavy machinery used will always present an element of risk and the public have to be shielded from such risks.

In today’s world, geotechnical drilling companies are able to work around the site; this rather than clumsily making the site work for them and their traditionally larger equipment. The point of this article has been to show you that there are very few situations now where you can’t get the drilling done that you need doing. So, if you’d like to find out more about our restricted access drilling services, then get in touch! Contact Borehole Solutions today on 01733 200 501. We’re the drilling company that combines quality with personality, we’re the drilling company for you!