Cuadrilla Resources has been ordered to plug and abandon Britain’s only two horizontal shale wells at the Preston New Road (PNR) Lancashire shale exploration site by the Oil & Gas Authority (OGA).
Cuadrilla was granted planning permission in October 2016 to develop PNR as a temporary exploration site to drill, hydraulically fracture, and flow test natural gas from up to four horizontal wells. Two wells were drilled in 2018 into the Bowland shale to vertical depths of about 2.25 km and laterally for a further 0.75 km each through the shale.
The wells were flow tested in 2019 and confirmed natural gas containing 89% methane, 6% ethane, and 2% propane, with virtually no impurities. Samples of 56° API condensate were also recovered along with the gas. Natural gas flowed to surface from a total of six propped fracture stages (out of 45 originally planned). About 1.3 MMcf total volume of natural gas was recovered, and gas flowed at a peak rate of over 0.275 MMcfd and stable flow rates of 60,000-100,000 cu ft/d.
The flow data represents only a partial test of production from a very short section of the wellbore as fracturing operations were suspended by the UK regulator in late August 2019 following an induced seismic event at PNR. The site was required to halt operations if tremors greater than the UK’s regulatory operating limit of 0.5 on the Richter Scale were recorded. Only 13% of the designed proppant volume had been injected into the shale prior to the suspension.
The wells have not been producing since late 2019. Cuadrilla expects shortly to mobilize a rig to begin the process of plugging the wells with cement and removing associated surface pipework and valves from the site.
Cuadrilla was formed in 2007 as a privately owned British exploration and production company focused on discovering and recovering natural resources, primarily natural gas, from shale rock. Cuadrilla is owned by AJ Lucas Group (96%), an Australian specialist service provider to the energy, mining, and infrastructure sector, and by present and past Cuadrilla employees (4%).
Spirit Energy is a joint venture partner with Cuadrilla at PNR and will provide funding towards the cost of plugging and abandonment.