Sizewell C nuclear plant campaigners challenge approval
Campaigners against the Sizewell C nuclear power station have written to Business Secretary Kwasi Kwarteng to legally challenge his decision to give the scheme the go-ahead.
The £20bn project for the Suffolk coast was given government approval in July.
However, the decision was against the advice of the Planning Inspectorate and those against the scheme said the consent was therefore "unlawful".
The government said it could not comment on a potential legal challenge.
The Together Against Sizewell C (TASC) campaign group said it had sent a pre-action protocol (PAP) letter, which signalled the start of the judicial review process.
It said it gave evidence to the examining authority that the plant should not be built where the water supply could not be guaranteed, and the coastline would not be resilient for the entire lifetime of the project.
In its report, the examining authority recommended that "unless the outstanding water supply strategy can be resolved and sufficient information provided to enable the secretary of state to carry out his obligations under the Habitats Regulations, the case for an order granting development consent for the application is not made out".
TASC said Mr Kwarteng's decision failed "to assess the implications of the project as a whole, by ignoring the issue of whether a permanent water supply could be secured".
The new plant would be built next to the existing Sizewell B, which is still generating electricity, and Sizewell A, which has been decommissioned.
It would be mainly funded by EDF which said the new two-reactor plant could generate 3.2 gigawatts of electricity, enough for about six million homes.
In the government's decision letter, it said "sufficient information has been provided to demonstrate that the applicant has options available to it that will ensure a permanent water supply is secured".
It said it was concluded that the "benefits outweigh the adverse impacts of the proposed development".
The government wants to build eight new nuclear power plants in a bid to reduce the UK's dependence on fossil fuels and energy imports.
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