The Environment Agency has approved new rules for work at the West Newton-B oil and gas site in East Yorkshire.
A decision document, dated earlier this month, made changes to the environmental permit to allow the clean-up and extended testing of the well and the use of new chemicals in drilling muds.
Equipment to evaluate the site’s sidetrack well, WNB-1z, is due to be delivered this month (May 2021). The work is expected to include well perforation, stimulation and flow testing.
The permit variations allow the site operator, Rathlin Energy, to burn waste gases in a flare on the site – but only during well clean-up and testing operations.
At other times, flaring is permitted only as a safety measure or because of the maintenance of surface equipment.
There are also restrictions on the release of waste gas into the atmosphere, known as venting.
This is allowed only for safety reasons or if the operator is carrying out a nitrogen or carbon dioxide lift, a process to improve the flow of hydrocarbons. Then, venting is permitted for a maximum of 45 minutes per hour.
The permit also prevents the discharge of surface water when most potentially polluting substances are stored on site or when drilling, testing, workovers or abandonment operations are taking place.
Rathlin is forbidden to flare waste gas until it has complied with key conditions from the Environment Agency (EA):
- Four weeks before start of gas flaring, Rathlin Energy must submit details of:
- baseline air quality study undertaken before activities began
- monitoring programme for during and after gas flaring
- method for calculating emissions from flare
- Two weeks before the start of activities, the company must submit details of baseline groundwater quality sampling for the site
The permit also requires Rathlin to carry out monitoring of gases, water and air quality. The sampling includes:
- Methane – before and at start of flaring and monthly after that
- Flare gas feed rate and combustion temperature – continuously during flaring
- nitrogen oxides, carbon monoxide, carbon dioxide and total volatile organic compounds (VOCs) – monthly
- Groundwater – before start of any operations, then every four weeks during periods of testing, followed by every three months afterwards
- Air quality – at four locations every six months
Rathlin applied for the permit variations in May 2020. It was required to provide extra information, including the impact of nitrogen oxide on air quality on nearby important wildlife sites.
The EA concluded that nitrogen oxides and sulphur dioxides generated by operations at West Newton-B would not affect any site of nature conservation, landscape and heritage, and/or protected species or habitats on the Greater Wash special protection area.
The EA said it was minimising emissions to air by setting limits in line with technical guidance. It said:
“This will aid the delivery of national air quality targets. We do not consider that we need to include any additional conditions in this permit.”
The EA also approved the company’s environmental risk assessment, noise management and odour management plans.