The latest planning application for oil production at the Wressle site near Scunthorpe overcomes the objections raised by a government planning inspector, Egdon Resources has said.
The company has submitted a third application after two previous schemes were refused by North Lincolnshire Council and the inspector.
But this latest application again seeks permission for controversial techniques to improve the flow of oil, including small scale hydraulic fracturing.
The company has added features, such as a new impermeable membrane and two extra water monitoring boreholes. The application also seeks to construct a new bund, tanker loading plinth, security facilities and roadway, increasing the size of the site by 0.12ha.
Improving oil flow
Egdon said it needed to improve the flow of oil at Wressle because fine particles had stuck to the perforations in the well casing during previous drilling and testing.
The planning statement, submitted with the application, said this would be tackled first by acidisation. This involves injecting dilute hydrofluoric acid into the well to dissolve particles in the surrounding sandstone, 4-6m away from the wellbore.
If this didn’t work, Egdon said it would then try a proppant squeeze. A slurry of water, chemicals and tiny ceramic beads would be pumped under pressure into the well, fracturing the surrounding rock. When the pressure was reduced, the beads were designed to prop open the fractures and allow the oil to flow.
Egdon said in the application:
“The Proposed Development relates to conventional oil and gas production and no High Volume Hydraulic Fracturing operations for shale gas or oil will take place.”
But the company’s environmental permit, issued by the Environment Agency, describes the proposed proppant squeeze at Wressle as “small scale hydraulic fracturing activity” and said it would require a Hydraulic Fracturing Plan.
Egdon said the proppant squeeze would be carried out once, rather than multiple times with high volume hydraulic fracturing. It would also use less liquid, the company said. It predicted the operation would use up to 150m3 of liquid – considerably less than the 735m3 per stage planned by Cuadrilla at its Lancashire site at Preston New Road.
The fractures would be spread up to 40m vertically and 40m laterally, Egdon said. This compares with fracture heights of 25-154m and lengths of 64m-313m predicted for the Preston New Road well.
Egdon said it would monitor the operation to ensure that fractures remained with the Millstone Grit formation.
If the proppant squeeze failed to improve the flow, Egdon said it would then drill a 25m sidetrack well.
Egdon said the new application addressed the main concerns of the planning inspector, who dismissed the company’s appeals earlier this year.
The inspector concluded that Egdon had not shown that “unacceptable adverse impacts to groundwater resources and water courses would not arise during the life of the development.”
But in the latest application the company said:
“The proposed development has demonstrated that it has comprehensively addressed and overcome the inspector’s reasons to dismiss the previous two appeals.”
Two key issues at the inquiry were the lack of a ground condition report and doubts about the suitability of the liner.
Egdon said it had now carried out geotechnical investigation of the site and proposed to install a new impermeable membrane and protective geotextiles.
A new reinforced concrete roadway on the site would provide greater weight distribution and protection, it added.
The inquiry also heard concerns about whether pollutants from the site could reach the main aquifer in the Lincolnshire Limestone.
Egdon said it had commissioned Envireau Water, the consultancy that gave evidence at the public inquiry, to do a hydrogeological risk assessment of the site.
This took core samples from two new boreholes and concluded that there was an impermeable claystone cap above the aquifer, protecting it from contamination. Egdon said the risk assessment concluded that all identified hazards ranged from “low” to “none”.
The new application also includes construction of a bunded area for oil storage tanks and a tanker loading bay. It further seeks to deepen three of the four existing groundwater boreholes to “ensure full penetration of the Sutton Sand formation”.
Community liaison and fund
The application has new plans for a community liaison group to include representatives of Broughton Town and Appleby Parish Councils. This was intended to provide information on planned operations and respond to local concerns, Egdon said.
The company also said it would set up a fund from proceeds of oil production at Wressle that would support “an agreed range of uses”.
It said the fund could “total a significant sum over the planned years of production”.
The application does not give details of what proportion of revenue would go into the fund. But it said the fund would be operated at “arm’s length” from the company.
Egdon said there would be more heavy goods vehicles visiting the site under the new plans than previously predicted.
The company said the number of HGVs (not movements) involved in site configuration was now 88 (up from 50 in the previous application), production 32 (up from 20) and decommissioning 288 (up from 232).
Egdon is seeking permission for 15 years of oil production at the Wressle site.
It said any gas produced would either be flared or used to generate electricity for export to the mains.
A site map of a different wellsite included with the application has now been replaced with the correct version.