Publication - Research and analysis

Prevalence of CO2 from disused mineral mines and the implications for residential buildings: research

In 2017 the NHS Lothian Incident Management Team investigated reported cases of ill health affecting residents of a recently built local authority housing estate. This research is looking for similar incidents and considers implications for building standards.

Prevalence of CO2 from disused mineral mines and the implications for residential buildings: research
Annex 1 – Table of Past Incidents

Annex 1 – Table of Past Incidents

Summary of past incidents (The Coal Authority data was generated from an incidents database and is not publicly available)

Date

Location

No. of people/units affected

Detail

Source

Issues in Scotland

03/11/1994

Coalburn, South Lanarkshire

1 residential property

Blackdamp emission at a residential property during the winter of 1994 lowered the O2 levels to a reported 12%. Two vents were installed into shaft 280634-003 and the shaft fill was grouted.

Coal Authority, 2018

30/05/1995

Coalburn, South Lanarkshire

No data

Ongoing gas monitoring carried out by British Coal regarding O2 deficient atmosphere, transferred to the Coal Authority. Upper section of shaft 280634-003 drilled and grouted to a depth of 12m. Shaft re-drilled through the grout plug and a passive vent installed into shaft to protect the building. Vent attached to side of building to vent above eaves level.

Coal Authority, 2018

08/08/1999

Kirkconnel, Dumfries and Galloway

Number of animal fatalities

Low O2 within dry stream bed (dead animals). Gas venting undertaken and continual monitoring.

Coal Authority, 2018

09/08/1999

Kirkconnel, Dumfries and Galloway

Number of bird and small animal fatalities

Possible gas emission at site of old shaft. Several dead birds and small animals in the vicinity. Shaft excavated to depth of 4m, no evidence of shaft lining found. Filled with concrete and reinforced cap constructed. Void above cap filled.

Coal Authority, 2018

12/08/1999

Kirkconnel, Dumfries and Galloway

Suspected gas emissions. Records showed no mine entries at this location but discussions with local residents suggested unlawful coal working. Sealing works were undertaken by Coal Authority.

Coal Authority, 2018

28/06/2001

Dysart, Fife

1 harbour store

O2 deficient atmosphere found in old store at Dysart Harbour. New security grille with access door installed and gap between top of wall and rock face sealed with security mesh. Building vented.

Coal Authority, 2018

25/10/2002

Fife (no village listed)

1 Elderly woman (1 residential property)

Gas service engineer called out due to the inability of woman to light her gas boiler. After investigation it was found they could not light a match due to serious O2 depletion. Mine gas incursion into the property was a probable cause. She contacted LA environmental health team and CA was called out. During discussions with the woman it emerged she had "been sleeping more than usual" over the previous few weeks (of unsettled/stormy weather) and the decision was taken to install a 24-hour O2 monitor in the property to gauge the scale of the problem. A press release was issued, and a targeted leaflet-drop arranged jointly by EH and the CA to warn of the potential for mine gas in the village.

Stakeholder Engagement

01/04/2004

Thornton, Fife

Multiple residential properties

Unable to light gas appliances–mine gas suspected. Issue affected multiple properties in the locality. Site investigation boreholes drilled. Site then drilled and grouted. Two underfloor fans installed, and a monitor alarm left in house, ventilation into affected workings installed to alleviate issue.

Coal Authority, 2018

10/11/2010

Coalburn South Lanarkshire

1 property

CO2 at very high levels entered previously treated building through a mine entry. The building underwent a change of use from commercial to residential and previous remediation altered. The property was subsequently demolished and ventilation into the shaft improved.

Coal Authority, 2018

April 2014

Gorebridge, Midlothian

165 people (22 for healthcare)

See IMT report

NHS Lothian, 2017

Anecdotal evidence in Scotland

1950’s

Cowdenbeath

No data but allegedly several properties

Reports in local press of people ‘suffering from mystery symptoms’. Subsidence at the sites also recorded and both sites were vacated and demolished.

Expert Consultation

Lochgelly

Expert Consultation

Other CO2 or O2 deficient events in the rest of the UK

1960s

NW England

4 (3 children, 1 fireman) dead

Asphyxiated in poorly sealed surface entrance to adit (blackdamp).

Sizer et al., 1996

1971-76

No detail

2 dead

Walked into old workings.

Unwin and Phil, 2007

1977

Portobello, Birtley, near Gateshead, 1977

2 dead

December 1977 two persons found dead from carbon monoxide poisoning in bungalow. Investigation showed that the gas had travelled some 200 meters underground in permeable, fissured strata from burning fill in an abandoned shaft.

Robinson, 2000

1979

Low Fell, NE England

0 (1 household)

Poorly capped mineshaft found in garden, although no methane and little blackdamp found.

Robinson, 2000

1979

Sunnybrow, County Durham

1 family, rehoused

Random testing revealed low O2 levels (below 14%). House had been built above stopping to seal off surface drift to abandoned mine. Council officials stated that the family had been living there for four years and had frequently complained of ill health.

Robinson, 2000

1980

Cramlington

2 families (and further 8 properties)

Complaints of breathlessness, low O2 (circa 11%) discovered on investigation. Further 8 properties were found to have problems. An improved ventilation system was installed under floor spaces, removal of suspended floor, insertion of plastic membrane (all unsuccessful).

Robinson, 2000.

1987

Seaton Sluice, Northumberland

15 properties on an estate

Emergency service called out by council officials after drop in pressure resulting in O2 deficient atmosphere. Cause possibly rising water levels and low pressure. A ventilated system emplaced with boreholes allowing gas to be released at the surface.

Robinson, 2000

1987

Newcastle-upon-Tyne

1 property

Woman and helpers moving into property suffered dizziness, nausea and headaches which passed on moving to fresh air. High CO2 and low O2 were recorded. Maximum CO2 recorded in the property was 7.05%. Spikes in CO2 found to be associated with drops in atmospheric pressure. A shallow venting shaft sunk into soil in property (ineffective), then new shafts sunk into the mine itself for ventilation.

Hendrick and Sizer, 1992

December 1993

Pegswood, Northumberland

Evacuation of number of homes

Falling atmospheric pressure caused problems with blackdamp. Fan stopped from a connecting colliery that had shut down.

Robinson, 2000

31/12/1994

Pegswood Nr. Morpeth

Number of properties

Properties were affected by the ingress of blackdamp from shallow mine workings. Cavities grouted up and vents installed into the shallow pillar and stall mine workings and mine entries in the locality. Monitoring indicated that the level of blackdamp had been significantly reduced, properties still affected were treated through installation of retrospective gas membranes.

Coal Authority, 2018

11/02/1995

Widdrington

1 fatality, ‘major incident’ at 1 property

An uncontrolled release of blackdamp through a mine entry causing a fatality. The building effected occupied a former pit head baths built over the mouth of the mine entry. A trench was excavated across the drift and backfilled with concrete and the old drift entrance within the factory was backfilled with concrete. A borehole was drilled into the drift inbye of the stopping and a ventilation chimney erected. Following discussions with the LA and HSE further works were undertaken to infill an inspection chamber with mass concrete which was left in the floor of the property.

Coal Authority, 2018

07/03/1995

Widdrington, Northumberland

1 (non-residential) property

O2 deficient atmosphere recorded within the property attributed to the presence of a mine shaft beneath the property. Works were undertaken to seal the mineshaft and a gas collecting system was installed into the shaft beneath the sealing works. A gas vent was constructed on the outside of the property to vent the shaft.

Coal Authority, 2018

No date

Cresswell, Northumberland

1 commercial property

Evidence of blackdamp entering commercial building. Treatment of mine entry undertaken, and ventilation introduced.

Coal Authority, 2018

1995

Widdrington, Northumberland

1 house

Occupants of privately-owned house showed symptoms of blackdamp exposure. House was a former fanhouse above a shaft. Shaft grouted, and vent pipe installed.

Robinson, 2000

1995

Widdington, Northumberland

1 and 1 dog dead

Disused mine entry in factory, makeshift stable in brick shed possibly due to dewatering allowing pathway in old drift.

Hansard, 2016

1995

Cramlington Primary School

0 (school)

Fan failure in old mine ventilation system. Police, mine rescue and environmental health officers called out. No health impacts noted.

Hansard, 2016

01/02/1997

Pegswood, Nr. Morpeth

Number of residential properties

CO2 detected in property. Existing vents from old workings enlarged. These were subsequently collected together in a combined manifold to enable the gas to be discharged from a common installation. Gas membranes fitted into affected houses.

Coal Authority, 2018

09/07/1997

Rhymney, South Wales

Commercial property

CO2 detected in the commercial premises. A 600mm diameter pipe installed from the existing pipe in the stoppings for the length of the adit beneath the properties. This was vented to a ventilation stack on land adjacent to the adit entrance.

Coal Authority, 2018

1998

Barnsley

1 dead (1 collapse)

A man collapsed while laying sewer pipes, son died rescuing father from trench. Blackdamp had seeped in from disused colliery.

Humphries, 2001

02/06/1999

Low Moor, Bradford, Yorkshire

1 residential property

Elevated levels of blackdamp (up to 9%) and low levels of O2 (down to 10%) found by Transco within the basement of the property after electrician working within the property complained of breathing difficulties. Drilling works identified an unrecorded shaft filled with pea gravel and the remaining shaft void was filled with high strength foamed concrete to the underside of the capping plate. A ventilation fan was temporarily installed in the cellar but was removed after the sealing works to the shaft were completed.

Coal Authority, 2018

23/06/1999

Low Moor, Bradford, Yorkshire

1 property (non-residential)

Shaft depression found to contain elevated CO2. 150mm pipe with monitoring facility placed into the excavation prior to backfilling.

Coal Authority, 2018

09/07/1997

Rhymney, South Wales

No specific data

CO2 detected in the premises. It was decided to install a 600mm diameter pipe from the existing pipe in the stoppings for the length of the adit beneath.

Coal Authority, 2018

28/08/1997

North Shields

Residential property(ies), no specific data

CO2 detected in property. Consideration of possible remediation works concluded that the problem was too widespread to solve by individual property treatment/venting etc. A fan test on a borehole sunk to the workings proved that it would be possible to control the gas emissions by installing a mechanical ventilating system to extract the gas in controlled manner.

Coal Authority, 2018

11/10/2000

Great Broughton, Cumbria

1 property (residential)

Residents of bungalow not able to light gas appliance. CO2 in general body up to 2.9%, 17.5% O2. Problem ongoing for 18 months. Monitoring suggested a good pathway from shallow unrecorded mine workings and driving force for the movement of gases appears to be changing atmospheric conditions. Remedial works undertaken.

Coal Authority, 2018

30/10/2000

Cockfield, County Durham

1 property

Ingress of elevated CO2 into a property causing ill health and inability to light appliances. Sealing works were undertaken on all passages between the underfloor area of the property and the living areas above. Extra sealing around skirting boards was also undertaken and service entry points sealed with foam. Two large diameter boreholes were sunk to these workings. A ventilation scheme was initially put in place at the property. This passive ventilation system was adjusted to connect the subfloor area to a vent arrangement in the birdbath in the front of the property.

Coal Authority, 2018

11/12/2000

Hunwick, County Durham

Number of residential properties

CO2 entering cottages from abandoned mine entries. The drifts were vented, and gas disappeared.

Coal Authority, 2018

11/12/2000

Hunwick, County Durham

1 Commercial property

CO2 entering factory canteen from shaft partially beneath building. Shaft treated and vented.

Coal Authority, 2018

26/01/2001

Crook, County Durham

No specific data

Mine entries emitting elevated CO2. Mine entries treated and vented.

Coal Authority, 2018

02/08/2001

Crook, County Durham

No specific data

Gas emission within woodland showed up to 16% CO2 present. Depression dug out and reinstated with on-site material.

Coal Authority, 2018

21/09/2001

Biddulph, Stoke on Trent

No specific data

CO2 concentrations up to 0.8% were detected within general body of living areas under steady atmospheric conditions. Ingress believed to be associated with shallow workings. Active ventilation installed at the property.

Coal Authority, 2018

12/11/2001

Moira, Derbyshire

Commercial property

Identified elevated CO2 leaking at industrial units. Passive ventilation installed.

Coal Authority, 2018

16/10/2002

Stoke on Trent

No specific data

Possible emission of CO2 and O2 deficiency. Gas monitoring unit removed from property, constructed new ventilation system.

Coal Authority, 2018

01/04/2004

Woolley, Wakefield, Yorkshire

Several residential properties

Long standing mine gas issue in residential properties. CO2 and smell when pressure low and wind from west. Venting fissures and filling in cellar have alleviated the problem, but low concentrations of gas still present in kitchen. A fan was installed beneath the living room floor but provided only a limited air flow. Two boreholes were drilled into Woolet Edge rock and nearby workings to vent and monitor. Cellar fitted with foam concrete, fissure sealed under the solid part of the lounge floor before sealing the whole room with a gas membrane and concrete floor. This subsequently caused smells in other rooms and a trench was excavated in the patio area to the south of the property to expose two fissures. Allowing these to vent outside the house appeared to have alleviated these problems.

Coal Authority, 2018

11/01/2005

Coleford, Forest of Dean

None identified

Discharge of O2 deficient air from mine entry. Removal of concrete capping, filling of void using clean stone. Excavation to formation and placement of RC shaft cap.

Coal Authority, 2018

01/03/2005

Tankersley, South Yorkshire

None identified (area extensively used by public)

Shaft cap over void shaft with 3” pipe in cap. 12% CO2 and low O2 gas readings within the pipe. The shaft cap was further secured by erecting 5m x 5m square 2.4m high palisade fencing with warning notices. Site monitored annually to ensure the fencing remains secure.

Coal Authority, 2018

15/07/2005

Ashington, Northumberland

None identified (potential effects to public area–museum)

Elevated CO2 leaking from shaft cap within museum. Remedial works undertaken, and shaft regularly monitored.

Coal Authority, 2018

14/02/2007

Pegswood, Nr. Morpeth

1 property

Continued blackdamp detected at property from shallow mine workings. Property retrospectively sealed.

Coal Authority, 2018

28/06/2007

Elescar, Barnsley, Yorkshire

Several residential properties

Residents complained of difficulty lighting fires in the house, caused by ingress of CO2 from shallow mine workings. Property demolished, including garage at rear and foundations grubbed out. Site was cleared and surrounded with timber and shiplap fencing.

Coal Authority, 2018

23/10/2008

Pegswood, Nr. Morepeth

1 residential property

Retrospective sealing works undertaken to property following ingress of elevated CO2 from shallow mine workings. Workings and nearby mine entries also vented.

Coal Authority, 2018

08/09/2009

Halfway, South Yorkshire

Several residential properties

Elevated levels of CO2 affecting properties on housing estate. Shallow workings vented in multiple locations across the estate.

Coal Authority, 2018

08/07/2010

Cwmbran, Monmouthshire

1 person (anecdotal)

Open adit in open land where low O2 levels have reportedly affected member of the public. The adit was sealed and access restricted.

Coal Authority, 2018

17/04/2012

Lower Brynamman, Ammanford, South Wales

1 commercial property

Elevated CO2 and methane entering commercial property from mine entry. Mine entry treated and vented, and monitoring facilities installed. Further sealing done at the monitoring point within a manhole chamber where CO2 and methane were entering the building.

Coal Authority, 2018

18/03/2014

Spennymoor, County Durham

None reported

Mine gas (blackdamp) issuing under pressure from manhole chamber over treated mine shaft at housing development. Shaft vented.

Coal Authority, 2018

21/01/2016

Rhymney, Tredegar, South Wales

Several properties

CO2 from abandoned mine entry affecting properties vegetation. Mine entries treated, and a number of ventilation stacks installed to remediate issue.

Coal Authority, 2018

28/02/217

Heanor, Derbyshire, East Midlands

Several residential properties

Ingress of elevated CO2 into property from shallow adit roadway beneath the property. Lower levels of CO2 also detected in neighbouring properties. Temporary venting installed into roadway to alleviate problem affecting neighbouring properties. Ventilation has reduced issue in affected property but not to an acceptable level. Consideration will be given to demolition and permanent ventilation.

Coal Authority, 2018

Anecdotal evidence or lacking data

1950s

NE England

No specific data

Number of mine gas surface incidents in domestic properties. Not just CO2 but O2 deficient (blackdamp).

Robinson, 2000

1995

Northumberland

Health of 1 woman

Anecdotal: woman falling asleep when blackdamp had reached level of sofa.

Hansard, 2016

No date

Hunterfield

1 fatality

Young boy fell into shallow ground collapse and overcome by CO2.

NHS Lothian, 2017

No date

No detail

1 collapse from exposure

Anecdotal evidence from HSE: one person overcome retrieving football from mine entrance.

Health and Safety, Executive. Personal communication. 31 March 2016.

No date

No detail

1 fatality

Anecdotal evidence from HSE: one death from someone exploring old mine. Overcome and could not be rescued.

Health and Safety Executive. Personal communication. 31 March 2016.

No date

No detail (possibly Yorkshire)

1 fatality

CO2 from old chalk quarry with 2-3m of chalk and soakaways put in for the roof drainage. Couple came to buy houses second hand. One man went into subsurface void and collapsed followed by second. Firemen called out and even he collapsed. O2 was brought down but sadly one man died.

Expert Consultation

No date

No detail

3 fatalities (anecdotal)

About three incidents where people have died in excavation on former open cast sites or chalk sites

Expert Consultation

Worldwide significant CO2 events

1953

Menzengraben mine, East Germany

Mine shaft roof shattered, 3 deaths (2 from asphyxiation)

Salt mines had unexpected explosion (“outburst”) of CO2 (common in salt mines). Two died of CO2 asphyxiation. One at 100m, one at 350m distance. Asphyxiation symptoms recorded at 530m distance.

Hedlund, 2012

1986

Lake Nyos, Cameroon

1,700 Fatalities, 3,500 livestock

Limnic eruption (lake overturn) ½ million tonnes of CO2 released.

BBC, 2018

Unknown/ late 1990s

Lorraine, France

Number of persons/ properties

Former iron and coal mines. Faulty gas appliances and symptoms of CO2 recorded. 8% CO2 and 7% O2 at times of pressure drop.

Lagny, 2015

1999

Rome, Italy

30 cows

Asphyxiated due to CO2 exposure.

Beaubien et al., 2003

1980s-2003

Lazio Region, Italy

10 fatalities (over 20 yrs.)

Fatalities from asphyxiation.

Beaubien et al., 2003

2000

Cava del Selci, Italy

1 person and multiple livestock/ animal fatalities

Home owner and grazing farm animals were asphyxiated by CO2 gas cloud arising from natural volcanic activity near Cava del Selci, Italy.

Chartered Institute of Environmental Health, 2008

2000

Lawrence County, Pennsylvania, USA

4 people in 3 homes

Numerous properties affected by low O2 and high CO2 near and on old strip mine. Sub slab positive pressure ventilation seemed successful mitigation.

Ehler, 2002

2001

West. Virginia, USA

2 people

Reports of dizziness and fatigue while in basement. Very high CO2 and low O2. CO2 level 9.5% and O2 level 14% recorded in crawlspace adjacent to basement.

Center for Disease Control, 2004

2002

Lawrence County, Pennsylvania, USA

73 properties

Low O2 and elevated CO2. Same case as above. Reaction of acidic minewaters with limestones.

Three other sites in Western PA also investigated and showed elevated CO2 and reduced O2 in homes. Site 1: CO2 3.52%, O2 16%. Site 2: CO2 > 25%. Site 3: CO2 14.7%, O2 6.8%. Remediation successful.

Laughrey and Baldassare, 2003

2002

Derry, Pennsylvania, USA

1 home

Two daughters with bedrooms in the basement awoke several times with increased hearth rate and difficulty breathing. CO2 levels recorded >10%, O2 levels <10%, on occasion CO2 exceeded 20%. House located on area with past surface and deep mining. CO2 higher following rainfall.

Laughrey and Baldassare, 2003

2006

Indiana, USA

3 properties

Elevated CO2. Maximum daily concentration of CO2 2%. Mitigation measure taken, but in one house the effects remained. Three mitigation measures attempted: block-wall depressurisation, block-wall and sub-slab depressurisation, and block-wall and sub-slab pressurisation, but none achieved safe CO2 levels. Excavation of an open trench and sub slab positive pressure ventilation seemed successful Risks remained at a drop in pressure.

Robinson, 2010

May 2006

Sullivan Mine, Kimberly, BC, Canada

4 fatalities

Zinc and iron mine. Over three days, four individuals died at a water monitoring station at toe of number one shaft waste dump.

Sullivan Mine Incident Technical Panel, 2010

Other mine gas issues (not CO2 or O2 deficient) in Scotland

14/07/1986

Chryston, N Lanarkshire

Possible leakage to series of properties

Report of methane accumulation in the area and in the Berryknowe housing estate on above shallow unworked coal and fractured sandstone

Expert consultation

24/10/2002

Leven, Fife

No data

Hole appeared in field issuing smoke. Spontaneous combustion materials dug out and cold edges sealed with sand barrier.

Coal Authority, 2018

10/11/1999

Leven, Fife

No data

Alleged burning in a coal seam. Excavation carried out and 4 monitoring boreholes drilled.

Coal Authority, 2018

References for Annex 1:

BBC. (2018). On this day in August 21, 1986: Hundreds gassed in Cameroon lake disaster. [online].

Beaubien, S., Ciotoli, G. and Lombardi, S. (2003). Carbon dioxide and radon gas hazard in the Alban Hills area (central Italy). Journal of Volcanology and Geothermal Research, 123(1-2), pp. 63-80.

Center for Disease Control. (2004). Brief Report: Investigation of a Home with Extremely Elevated Carbon Dioxide Levels – West Virginia, December 2003. 53(50).

Chartered Institute of Environmental Health. (2008). The Local Authority Guide to Ground Gas. London.

CL:AIRE. (2018). Ground gas monitoring and ‘worst-case’ conditions. CL:AIRE technical bulletin. TB 17.

Coal Authority. (2018). Coal Authority Report.

Ehler, W.C. (2002). Dangerous Atmosphere created by Strip Mine Soil.

Hansard. (2016). Mine workings. Northumberland.

Health and Safety Executive. (HSE). Personal communication. 31 March 2016.

Hedlund, F. (2012). The extreme carbon dioxide outburst at the Menzengraben potash mine 7 July 1953. Safety Science, 50(3), pp. 537-553.

Hendrick, D. and Sizer, K. (1992). "Breathing" coal mines and surface asphyxiation from stythe (black damp). BMJ, 305(6852), pp. 509-510.

Humphries, P. (2001). Deep concern: The risk of gas leaks from disused mines. The Guardian. [online].

Lagny, C. (2015). Noxious gas emissions above former coal and iron mines in Lorraine due to the presence of iron sulphides. Environmental Earth Sciences, 74(7), pp. 6303-6313.

Laughrey, C. and Baldassare, F. (2003). Some applications of isotope geochemistry for determining sources of stray carbon dioxide gas. Environmental Geosciences, 10(3), pp. 107-122.

NHS Lothian. (2017). Carbon Dioxide Incident in Gorebridge Midlothian, April 2014. Final Report of the Incident Management Team.

Rippon, J. H. (2002). Coal. In: Trewin, N. H. (ed.) The Geology of Scotland. The Geological Society, London, pp. 449-454.

Robinson, R. (2000). Mine gas hazards in the surface environment. Mining Technology, 109(3), pp. 228-236.

Robinson, B.A. (2010). Occurrence and attempted mitigation of carbon dioxide in a home constructed on reclaimed coal-mine spoil, Pike County, Indiana. US Department of the Interior, US Geological Survey.

Sizer, K., Creedy, D. and Sceal, J. (1996). Methane and Other Gases from Disused Coal Mines: The Planning Response Technical Report. London: Wardell Armstrong.

Sullivan Mine Incident Technical Panel. (2010). Sullivan Mine Fatalities Technical Investigations Summary Report: Mine waste respiration-induced air quality risks March 2010.

Unwin, I.D. and Phil, M. (2007). Mine monitoring for safety and health. Monograph.


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