Environment Agency successfully resists challenge to HS2 tunnelling

19 Nov 2021

Planning and Environment

Today the High Court handed down judgment in R(on the application of Misbourne Environmental Protection Ltd) v Environment Agency [2021] EWHC 3094 (Admin), refusing permission to bring a judicial review on a renewed application.

The Environment Agency decided to grant consent to HS2 Limited for the construction of a 16 kilometre twin tunnel lying between the M25 and South Health in the Chilterns. The tunnel is to be constructed below groundwater, and consent was also granted for the abstraction (removal) of groundwater associated with the construction.

This decision was challenged by a private company set up by environmental campaigning groups concerned about protecting the nearby River Misbourne and the local chalk aquifer. The Claimant company contended that the decision was unlawful for three reasons.

Firstly, the Claimant alleged that the Environment Agency had wrongly directed itself such that the consent had been granted erroneously having regard to Article 4(1) of the Water Framework Directive, which is retained EU law. Article 4(1) requires Member States, in river basin management plans for surface waters, to “implement the necessary measures to prevent deterioration of the status of all bodies of surface water”, unless certain derogations apply. A “deterioration of the status” of such a water body has been interpreted to include any deterioration of status of the body of water, even if transitory, will fall within the scope of Article 4(1) (Bund Naturshatz v Bundesrepublik Deutschland C-461/13 at [69]).

When granting the consent, the Environment Agency (relying on assessments conducted by HS2) determined, as a matter of fact, that there would be minor localised and/or temporary effects on the relevant water body, but that these were insufficient to affect an element at the water body scale. Therefore, these effects did not affect the status of the body of water for the purposes of the Water Framework Directive. In particular, HS2 Ltd classified a “temporary” effect as an effect lasting less than 3 years, which reflected half the period of the River Basin Management Plan cycle. Accordingly, the Environment Agency considered that no derogation applied and that granting the consent fell within the remit of Article 4(1).

The Claimant argued that by making this determination, the Environment Agency had focused only on permanent effects and failed to consider temporary effects which could change “the status of the water body” in Water Framework Directive terms. It argued that, taking a precautionary approach, the risks of the temporary effects were such that the Environment Agency’s approach was unlawful.

In finding for the Environment Agency, Lieven J noted that the concept of “status” must involve “more than some purely transitory effect, however significant it might be” and that there was a judgment to be made over what period of time the effect must last. She considered that the 3-year approach adopted was a matter of environmental expertise and judgment with which the Court should be very slow to interfere, and that on the facts, it was a rational approach. Accordingly, the ground of challenge strayed into a challenge to the rational professional judgment as to the extent of the risk and how long it might last, which are not capable of determination by judicial review.

Secondly, the Claimant argued that the Environment Agency should have required HS2 to apply for a separate environmental permit, under the Environmental Permitting (England and Wales) Regulations 2016 before granting the consent. It was argued that a discharge permit was required for the discharge of grout through the tunnelling process. The Environment Agency considered the risk of discharge, and the risk of it contaminating the groundwater, with mitigation, was extremely low. Lieven J considered that this decision was clearly a technical, factual question for the regulator and that the matters contested by the Claimant had been considered. As a result, no error of law arose.

Thirdly, the Claimant argued that the Environment Agency failed to properly consider the cumulative impacts of the works. In particular, the Claimant raised concerns about an incident at the new shaft at Chalfont St Peter which involved the loss of bentonite slurry. However, the Claimant also agreed there was no legal provision requiring HS2 Limited to submit proposals for the entire tunnelling works. Having found that the incident had been thoroughly investigated, Lieven J dismissed this ground on the basis that this too was an issue where there was a considerable measure of professional judgment to be exercised and not an issue the court could properly decide.

Consequently, permission to bring judicial review proceedings was refused.

Lisa Busch QC and Estelle Dehon acted for the successful defendant.