Site Investigation Nelson – Geoinvestigate

Let Geoinvestigate quote for your next coal mining risk assessment (CMRA), coal mining investigation, mining report, mineshaft investigation, desk study, ground investigation, borehole investigation, site investigation, geotechnical, geo-environmental or contaminated land investigation in Lancashire including the towns and cities of Clitheroe, Burnley, Blackburn, Chorley, Bolton, Bury, Rochdale, Leigh, Oldham and Manchester on the Great Lancashire Coalfield.coal miner underground 2

With over 18 years in the business, several regional offices offering a nationwide service including offices in Cumbria and Lancashire, highly qualified and experienced professional staff, and its own drilling equipment, Geoinvestigate is best placed to give the most competitive and professional coal mining service.New cmra pics

If you need assistance with a planning application or a coal mining risk assessment (CMRA), a general site investigation or any of our other services please contact us at one of our Regional Offices.

Call 01613 272613 or email enquiries

Or if your enquiry is just about Coal Mining CALL FREE on 0800 1712011


The following article gives a brief background to mining activity in the Lancashire Coalfield and the services Geoinvestigate provide to enable house buyers, home owners, developers, architects, surveyors and engineers both to buy to build safely in respect of the regions coal mining legacy.

The Great Lancashire Coalfield

The Lancashire Coalfield in North West England was one of the most important British coalfields. Its coal seams were formed from the vegetation of tropical swampy forests in the Carboniferous period over 300 million years ago.

The Romans may have been the first to use coal in Lancashire and its shallow seams and outcrops were exploited on a small scale from the Middle Ages and extensively after the start of the Industrial Revolution. The coalfield was at the forefront of innovation in coal mining, prompting the country’s first canals, use of steam engines and creating conditions favourable for rapid industrialisation.

The pits on the coalfield were at their most productive in 1907 when more than 26 million tons of coal were produced. By 1967 just 21 collieries remained. Parkside Colliery in Newton-le-Willows, the last deep mine to be sunk on the coalfield, was closed in 1993.


The geology of the coalfield consists of the coal seams of the Upper, Middle and Lower Coal Measures, layers of sandstones, shales and coal of varying thickness, which were laid down in the Carboniferous period over 300 million years ago. The coal seams were formed from the vegetation of tropical swampy forests. The coal in Lancashire is bituminous with 30–40% volatile matter varying in hardness from seam to seam.

The coal measures were subsequently subjected to folding accounting for the dip towards the south and west and faulting occurred at this time. The Coal Measures are over 4000 feet thick and coal accounts for approximately 4% of their thickness. The coalfield is crossed by several major faults which generally run in a north and south direction. The most significant easterly fault described by Edward Hull throws the strata down to the east. It was worked from Fairbottom in Ashton-under-Lyne across the River Medlock to Oldham and onwards to the west of Rochdale. The Red Rock Fault skirts the north-west extremity of the North Staffordshire coalfield towards Macclesfield and Poynton Colliery in Cheshire. The Irwell Valley or Pendleton Fault passes Clifton and Kearsley where it throws the coal measures down to the north-east. It has a throw of 3000 feet and the area is still geologically active and subject to earth tremors. A fault with a large horizontal but small vertical throw is found at Tyldesley. In the deep mines at the southern edge of the coalfield, the Plodder mine in Leigh and the Arley mine in Tyldesley were hot; the miners worked in temperatures of over 100 degrees Fahrenheit.

Five substantial faults affect the Wigan Coalfield running nearly parallel to and equidistant from each other. The Great Haigh Fault begins near Bickershaw Colliery and passes northward through Hindley, Kirkless Hall, Haigh, and Arley to the west of Adlington Park. The Great Standish or St Catherine’s Fault has a downthrow to the east and passes under St. Catherine’s Church at Ince. The Giant’s Hall Fault passes by Abram, west of Ince Hall Colliery, west of Gidlow and under Giant’s Hall Farm to Standish Church. The Great Shevington Fault passes by Hawkley Hall and east of Kirkless Hall. The Great Pemberton Fault is a downthrow and passes Pemberton, Orrell and to the west of Shevington. Further west are the Great Upholland Fault, the Lathom Fault the Great Boundary Fault stretching from Bickerstaffe to about two miles east of Ormskirk.

Borehole Investigation of Shallow Coal Mining    

Over the past 6 months Geoinvestigate’s new compact microdrill system has proven its worth and that it’s just the answer for investigating Bristol and Somersets coal mining legacy. Microdrill offers restricted access, small diameter rotary open-hole drilling which is first and foremost SAFE, fast, clean, quiet, cost effective and environmentally friendly. New Microdrill has been designed for probing for shallow workings in limestone, sandstone and coal as well as locating mine shafts and sinkholes.

Recently Microdrill was in action in Newcastle, Co Durham on the Durham and Northumberland Coalfield. Having previously obtained a coal drilling permit from the Coal Authority to drill with water flush Microdrill was delivered to site on the back of a standard flatbed trailer.

Microdrilling Site Investigation

Shallow mine working investigation of a housing estate in Newcastle

Access to the drilling positions in several gardens was tricky but achievable with Microdrill.

In accordance with Coal Authority Guidance on Managing the Risk of Hazardous Gases when Drilling or Piling Near Coal (essentially a Code of practice for safe drilling and piling through coal) water flush was in this instance considered to be the safest flushing medium. This is because there was assessed to be an unknown or undetermined gas risk as is so often the case in exploratory drilling works on the UK coalfields.


The Coal Authority normally stipulates small volume water injection flush for their internally managed exploratory drilling works because it ensures minimal risk to the public from hazardous gases including carbon dioxide, methane and carbon monoxide. In fact it is rare under the Coal Authorities strict safety policy for drilling through coal for them to permit anything else but water.

Microdrill on it's 50th job
                                              New Microdrill on it’s 50th job

The Coal Authorities strict policy with regard to water flush is something to be considered by site investigation companies when compiling a Coal Mining Risk Assessment (CMRA) or drawing-up a source-pathway-receptor based risk assessment for drilling permit application.

It should also be borne in mind by drilling contractors and consultants that the CA polices drill sites checking some 10% of drill sites per year to ensure compliance with the permit. A change in drill flush from that originally agreed with the CA would be a breach of terms and conditions and could result in prosecution.

New Microdrill has been demoed to the CA who gave it their nod of approval suggesting that in their opinion it was easily capable of reaching 50m and probably much deeper though up till now it has only been tested to 30m which is typically the limit for shallow mining investigation.


Microdrill investigating shallow mine workings on the Durham and Northumberland Coalfields


Advantages of Geoinvestigate Microdrill

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Advantages of Geoinvestigate Microdrill

  • Health & Safety           makes hand drilling obsolete
  • Noise & dust               reduced noise and dust emissions
  • Adjustable mast           drilling under buildings, services & obstructions
  • Mast guard                  safe operation even when drilling inclined
  • High productivity          more metres, more information & less uncertainty
  • Water flush                  safer drilling in mine workings and openings
  • Uses less water           tidier site and less reinstatement costs
  • Smaller hole                faster penetration, less solid waste disposal
  • Micro drill size             access to small spaces + sensitive urban locations


Microdrill is a safer, faster, quieter, cleaner, more cost effective and site friendlier way of drilling holes in tight spaces and restricted access locations in towns, suburbs, gardens and driveways.



Coal mining Investigation Durham Coalfield. Intact coal turns drill water black

Geoinvestigate featured in newspaper


Geoinvestigate Hartlepool

If you require a coal mining investigation, Phase 1 desk study, coal mining risk assessment (CMRA), Phase 2 intrusive site investigation, geotechnical investigation, ground investigation or you need a contaminated land survey or landfill gas survey, trial pitting or borehole drilling please do not hesitate to contact one of our regional offices. Our team are only too happy to assist with your enquiry and will ensure that you get our most competitive quote.