The Horse Hill production site in Surrey has cut its planned capacity for crude oil storage by more than 80%.
Horse Hill Developments Limited (HHDL) applied in 2020 for consent to store up to 285 tonnes of crude oil at the site near Gatwick airport.
But in a letter to Surrey County Council earlier this month, the company confirmed it was now scaling back storage capacity to less than 50 tonnes.
“As a result of the most recent review of legislation and a re-assessment of the site’s storage inventory, the Applicant is able to reduce the need for crude oil storage to a maximum of 49 tonnes.”
HHDL said the reduction had been made possible “through the adoption of more efficient site operations”. It said it it expected to transport about 60 tonnes of crude oil off site each day.
DrillOrDrop asked for the reason behind the change, given that Horse Hill has planning permission to expand oil output from the current one to a total of six producing wells. This article will be updated with any response.
Oil production from the Horse Hill-1 well began in March 2020 and official data has been published up to December 2020. The figures show that monthly output peaked in April 2020 at 981 tonnes, falling to 341 tonnes in December 2020 after a well workover.
Under the original 285 tonne-capacity, Horse Hill would have been subject to the COMAH or Control of Major Accident Hazards Regulations. It would have been classified as a top-tier COMAH site and required to prepare a detailed safety report, test an on-site emergency plan and supply information to local authorities and the public.
HHDL said the reduction in storage capacity would reclassify Horse Hill as a lower-tier COMAH site, with lesser regulatory requirements.
As part of the changes, HHDL said it was reducing the number of crude oil storage tanks at Horse Hill from eight to one.
It also said it would no longer need equipment including a blown down vessel, flow manifold, data acquisition, compressor, choke, safety shutdown, office and workshop and gauge tanks.
The decision on crude oil storage at Horse Hill will be made under delegated powers by planners at Surrey County Council. The Health and Safety Executive is responsible for COMAH regulations in the oil and gas industry. It acts jointly with the Environment Agency.