Chemical tank at UKOG’s Horse Hill oil site in Surrey. Photo: Weald Action Group

The government has no plans to extend the moratorium on fracking to other forms of well stimulation, correspondence has revealed.

The moratorium was announced in November 2019 because of the risk of induced earth tremors. It applies only to hydraulic fracturing, defined in law by the volume of water pumped into a well.

In February 2020, more than 600 academics, politicians and campaigners signed a letter asking ministers to replace the current moratorium with an outright ban and to extend it to all other forms of well stimulation.

The letter was coordinated by Brockham Oil Watch, a community group in Surrey concerned about local unconventional oil and gas extraction.

The group sent copies to the prime minister, secretaries of state for business, environment and local government and the energy minister, Kwasi Kwarteng.

The letter cited research which, the group said, suggests that acid stimulation and hydraulic fracturing share many of the same risks. But many of the restrictions on fracking do not apply to other forms of well stimulation.

A legal brief accompanying the letter said there was no clarity over what legal and regulatory controls applied to operations that fell outside the legal definition of hydraulic fracturing.

In a reply released by Brockham Oil Watch, Mr Kwarteng described acidisation as “a common technique carried out to clean and develop wells”. Letter from Kwasi Kwarteng to Brockham Oil Watch

He said the technique was regulated by the Environment Agency, which was satisfied that the current regulations provided “a high standard of environmental protection”. Companies had to demonstrate how they would provide a high level of protection to people and the environment, Mr Kwarteng said.

A spokesperson for Brockham Oil Watch said Mr Kwarteng’s letter did not respond to the issues raised in the letter or referenced in the legal brief:

“The response is a polite but firm refusal and dismissal of our concerns.

“Specifically, on acidisation, it is true that the EA [Environment Agency] regulates this area, but the EA has failed to clarify the boundaries between well maintenance techniques and acid stimulation – a fracking-like technique.

“As it stands, permits and exclusions are granted based on the oil and gas firms’ stated intent, which results in insufficient restrictions, reporting and monitoring to guard against acid stimulation taking place under the guise of well maintenance.

“The EA’s regulatory position remains opaque, with no clarity whatsoever over where the boundary between unacceptably dangerous acid stimulation and routine well maintenance lies.

Brockham Oil Watch also said confusion remained about which operations required hydraulic fracturing plans.

Mr Kwarteng said in his letter that the Oil & Gas Authority had given examples of when a hydraulic fracture plan was required.

But the ministerial statement on the moratorium, published on 4 November 2019, referred to both hydraulic fracture plans and hydraulic fracturing consents. These are two different regulatory consents that apply to operations of different scope, the group said:

“This highlights the many inconsistencies in the legal and regulatory framework for hydraulic fracturing and the need for an expanded ban for all well stimulation treatments.”