Shale gas companies must show they have considered how drilling could affect old mining features in coalfield areas, according to revised advice on exploration plans.
DrillOrDrop has learned that the government agency which oversees the impacts of mining has changed its policy on how to respond to local councils about shale gas exploration.
As more proposals are submitted, the Coal Authority is now telling planning authorities they may need to consider issues such as ground stability, mine gas and hydrogeology in areas where there are deep abandoned mines.
Previously, the organisation responded only where there were high risks to development on the surface from shallow workings.
In a recent response to an application, the Coal Authority said the developer must demonstrate that it had “appropriately considered and mitigated” the possible ways that shale gas exploration and mining features could interact.
There have been five shale gas applications in the East Midlands in former mining areas in the past three years and more are expected.
IGas sites at Springs Road, Misson, and Tinker Lane near Blyth, both in Nottinghamshire, are underway. Ineos Upstream has permission for exploratory drilling at Common Road in Harthill, south Yorkshire. It is also waiting for decisions on sites at Woodsetts in south Yorkshire and Marsh Lane in north east Derbyshire.
Response to Woodsetts plans
The change in Coal Authority policy came to light in different responses the organisation made to the Ineos plans for Woodsetts.
The company has made two applications for the land off Dinnington Road. The first, submitted in October 2017, was refused by Rotherham Borough Council. The second, submitted in June 2018 and yet to be decided, was for the same site with the same description. The company’s planning statement and environmental report contained the same information on risks from former coal mining.
But the responses to the applications from the Coal Authority were different.
On 29 November 2017, a letter from the Coal Authority to Rotherham Council on the first Ineos application said:
“I can confirm that the above planning application has been sent to us incorrectly for consultation.”
“The application site does not [Coal Authority emphasis) fall with the defined Development High Risk Area and is located instead within the defined Development Low Risk Area. This means that there is no requirement under the risk-based approach that has been agreed with the LPA for a Coal Mining Risk Assessment to be submitted or for The Coal Authority to be consulted.”
But on 29 June 2018, in response to the second Ineos application, the Coal Authority said:
“The Coal Authority records indicate that the application site is located in an area of former deep mining activity. We hold no records of any coal mining activity having taken place at shallow depth at this location.”
“From a planning perspective, in such areas as this where worked coal seams are present beneath the site, the potential impacts arising from such works in relation to ground stability and mine gas pathways, as well as hydrogeology should be properly considered.
“In particular sufficient consideration needs to be given to the stability of the geology of the site which may be affected by the proposed development. The LPA therefore need to ensure that they are satisfied that they have adequate information in this respect in order to inform the decision making process.”
In the period between the two Woodsetts consultations, seismologist Emeritus Professor Peter Styles has raised concerns about fracking in former mining areas (DrillOrDrop report).
The four other shale gas sites in the East Midlands appear to have been considered under the previous Coal Authority policy.
Change of policy
Nick Ethelstone, Head of Development at the Coal Authority, told DrillOrDrop:
“The Coal Authority’s position to the Ineos proposal at Woodsetts has not changed but our response draws the local planning authority’s attention to issues which may need to be considered – such as ground stability, mine gas and hydrogeology.”
“We have highlighted that the developer must demonstrate to the planning authority that it has appropriately considered and mitigated the possible effects of interaction between the proposed development and the mining features.”
Mr Ethelstone added:
“Traditionally, our risk based approach to development on the coalfields is focussed on proposals that fall within what we call Development High Risk Areas. These include all coal mining risks which may have an impact on surface development, such as shafts and shallow workings. We share GIS information with local planning authorities and we are only usually consulted on applications that fall within the High Risk Area. Development Low Risk areas include those with abandoned deep mining activity, such as this site.”
He said that in the period between the two consultations – November 2017 and June 2018 – the Coal Authority carried out a wider review of how it responded to proposals that were not in Development High Risk Areas but which may interact with abandoned mines.
“The Coal Authority continually reviews its processes and guidance and considers them against the types of planning application which are being made. As more applications involving deep drilling are now being brought forward, the Coal Authority has updated local planning authorities on when it should be consulted.
Asked whether the Coal Authority would now review its response on the Misson, Tinker Lane, Harthill and Marsh Lane applications, the organisation said:
“The Coal Authority has not altered its policy or approach to deep drilling applications but has amended the informative information we send out for any deep drilling proposal which is outside of the Coal Authority Development High Risk Areas. As this is an informative note, which would not fundamentally alter our response to previous proposals, we will not be revisiting them.”
Change in consultant’s advice
The advice to Rotherham Council from its mining consultant, SYMAS, also changed between the two consultations.
In the first response in November 2017, SYMAS said:
“Abandonment plan records indicate the proposed drill well will intercept Dinnington Colliery Barnsley coal seam workings at a depth of approximately 584m.
“The UK’s deep coal mines have now closed. Deep coal mining subsidence in the area has now ceased and the area can be regarded as stable.”
This was repeated in the second response in June 2018. But the consultant added concerns about some of the information in the application on mine workings:
“there does appear to be some inconsistency as to accurate predicted depths of the coal workings and whether first or secondary casing is proposed to below them.”
SYMAS also said there were no details of how regulators would inspect the borehole during exploration operations. It said the council should clarify:
- Accurate detail on predicted coal mining depths and well/casing designs
- Whether the Coal Authority anticipate the proposals would affect its liabilities
- Details of independent/regulator inspections during the works to verify each casing depth achieved
Shale gas development in coalfield areas was discussed at a parliamentary group meeting this month. DrillOrDrop report