Sizewell C, Leiston – Environmental Permit Application

ENVIRONMENT AGENCY

New bespoke application for an environmental permit under the Environmental Permitting

(England and Wales) Regulations 2016

We’ve received an application for a permit from Sizewell C Limited. We must decide whether to grant or refuse the application. If we grant it, we must decide what conditions to include in the permit.

Application number: EPR/HB3542KC/A001

Regulated facility type: Effluent treatment systems serving construction-related activities taking place across the Main Development Site (MDS), referred to throughout the application as the “site”. A combined discharge from the Onshore Flow Collection Chamber (CDO Collection Chamber) will be made to the North Sea via the Combined Drainage Outfall (CDO).

Regulated facility address: Sizewell C construction site, Sizewell, Leiston, Suffolk, IP16 4UR

National grid reference (NGR) discharge points:

? A1 Discharge of treated surface water run-off from the Main Construction Area (MCA) at TM 47980 64343

? A2 Discharge of groundwater from the MCA, including water produced by the installation and development of wells at TM 47980 64343

? A3 Discharge of treated foul water from the MCA (from sewage treatment plant known as ‘HAJ 1.1’) at TM 47980 64343

? A4 Discharge of treated foul water from the Temporary Construction Area (TCA) (from sewage treatment plant known as ‘HAJ 1.2’) at TM 47980 64343

? A5 Discharge of treated foul water from the TCA (from sewage treatment plant known as ‘HAJ 1.3’) at TM 47980 64343

? A6 Discharge of treated water from the sweeper tip facility at TM 47980 64343

? A7 Discharge of treated water from Bentonite Plant at TM 47980 64343

Receiving environment:

All discharges to the North Sea

Effluent types:

? All waste streams are trade effluent or treated sewage effluent associated with construction related activities

Volumes:

? Effluent via A1 Maximum of 34,560 cubic metres per day

? Effluent via A2 Maximum of 21,600 cubic metres per day

? Effluent via A3 Maximum of 2,143 cubic metres per day

? Effluent via A4 Maximum of 389 cubic metres per day

? Effluent via A5 Maximum of 1,789 cubic metres per day

? Effluent via A6 Maximum of 97 cubic metres per day

? Effluent via A7 Maximum of 400 cubic metres per day

What does the applicant want to do?

The applicant has applied for a new bespoke environmental permit application to regulate the proposed discharge of several (seven) effluent sources which will be generated from construction-related activities taking place across the Main Development Site (MDS), referred to throughout the application as the “site”.

How to view the application

The application can be viewed online using the link below to our e-consultation tool (known as Citizen Space):

https://consult.environment-agency.gov.uk/psc/ip16-4ur-sizewell-c-limited-epr-hb3542kc-a001

Please contact us via e-mail at psc-waterquality@environment-agency.gov.uk or contact us on 03708 506 506 to arrange to see the application documents if you are unable to access Citizen Space.

How to comment on the application

If you have any comments send these by 19 June 2025.

Comments can be made online via Citizen Space using the link below:

https://consult.environment-agency.gov.uk/psc/ip16-4ur-sizewell-c-limited-epr-hb3542kc-a001

Via email: psc-waterquality@environment-agency.gov.uk

Via post: The Environment Agency, IPS WO Team, Quadrant 2, 99 Parkway Avenue, Sheffield, S9 4WF

For advice about how to make a representation or if you are unable to make a representation via e-mail, please call 03708 506 506. Please quote the application number in any correspondence.

The Environment Agency will normally put any comments it receives on the public register. This includes your name but not your personal contact details. Please tell us if you do not want your response to be public. The privacy notice for permit applicants/operators can be viewed at: https://www.gov.uk/guidance/environmental-permits-privacy-notice

Find out more about our regulation of the Sizewell C (SZC) site via our GOV.UK page at the link below:

https://www.gov.uk/guidance/sizewell-nuclear-regulation