CO2 incident in Midlothian - final report

09 January 2018

Article: 52/104

A final report into the investigation into carbon dioxide (CO2) leaks into homes in the former mining village of Gorebridge in Midlothian was published on 22 December 2017.

The report was completed by the multi-disciplinary Incident Management Team (IMT), which was created to investigate Scotland’s most serious CO2-related incident. This IMT was led by NHS Lothian and comprised partner organisations, including Midlothian Council, Health Protection Scotland and Scottish Environment Protection Agency (SEPA).

The IMT was formed after reports of illness among residents in Gorebridge where CO2 was identified an having seeped into newly-built homes in the former mining area. Between September 2013 and September 2014, 22 residents from a total of 165 in the affected area made contact with healthcare services because of headaches, dry coughs, dizziness and anxiety.

The IMT identified that the seepage of CO2, into the residential houses originated from the old mine workings. This represented a significant ongoing risk to the health of residents and required action. The seepage of CO2 into the houses was thought to have been associated with a number of potential pathways including un-grouted disused mine shafts, natural cracks in the ground and man-made interventions over time.

The IMT has made a total of 26 recommendations to prevent a similar situation from happening again in other areas, by advising Scottish and the UK Government on areas where national level review, research and guidance are required. It has also made recommendations for action by local authorities that are likely to have housing developments on similar sites to prevent a similar threat to public health. On the basis of the investigations and following consideration of the current processes for assessing the need for mine gas mitigation for new build development, the IMT also recommended that mine gas mitigation measures should be made mandatory in all new residential and similar developments, in all areas of Scotland designated as former mining areas. 

The report concluded that the seepage of CO2 into the houses in Gorebridge was a rare, complex and costly incident associated with old coal mine workings. This incident is, to date, probably the most serious such CO2 related incident in Scotland.

Source: NHS Lothian News Release, 22 December 2018