Draft Response to the Fifth Consultation of the Proposed
Development of Sizewell C Nuclear Power Station
Following submission and acceptance of EDF’s Development Consent Order Application (DCO) by the Planning Inspectorate (PINS) and submission of a s56 Relevant Representation by MLSG and others, EDF has submitted a number of potential changes to the DCO for public consultation. This consultation has effectively paused the DCO examination process and EDF will submit substantive changes to PINS week commencing 11th January 2021 based on consideration of responses to this consultation and the needs, as EDF see them, of the project.
1. MLSG are disappointed, once again, that following 4 previous consultations over a 9-year period, after submission and acceptance of an inadequate DCO and submission of s56 Relevant Representations, that EDF have changed their minds and added yet another public consultation outside of the formal National Strategic Infrastructure Planning process. The nature of the issues within this consultation, should they go forward as substantive changes to the DCO and be accepted by the Examining Authority (ExA), will require further submissions to amend or replace existing Relevant Representations already submitted to PINS. Such behaviour, so soon after the s56 consultation period ended, shows that these changes were well formed even before the DCO was submitted for examination acceptance and would have been more properly dealt with by delaying the DCO submission to ensure that the DCO represented the expected scope and definition of the project from the beginning.
2. We are, once again, disappointed that clarification of the design of the hard coastal defence (HCD) is still lacking, although it is now clearly a greater threat to coastal stability and erosion than sketched out in the DCO itself. As coastal erosion continues apace along this part of the coast along with increased frequency and ferocity of storms, the advanced hard point created by the HCD and beach landing facility (BLF) at the northern extreme of the site will interrupt sediment transport across the front of all the Sizewell sites and potentially damage areas south of the site at Thorpeness and Aldeburgh because of accretion local to the Sizewell C site.
3. Constraints on the site that have required pylons to carry high voltage connections from the generators to the substation, instead of via underground cable runs and a HCD that previously advanced to within a few meters of the front of the existing sacrificial dune is too constrained at 32 hectares to host two nuclear reactors. This is supported by the fact that EN-6 envisages single nuclear reactors to have a site size of around 30 hectares and Hinkley Point C operational site is approximately 45 hectares. Furthermore, in raising the HCD to 14m from 10.2m, the toe of the HCD will now move ~8m towards the beach and will likely go beyond the existing sacrificial dune and into the beach. Proposed adaptation in 2046 will take the toe of the HCD even further towards the sea, earlier than discussed in the DCO.
4. We remain concerned that EDF place excessive reliance on sediment accretion north of the site to protect both Minsmere South Levels and the new SSSI crossing as there is no guarantee that the accretion will occur either early enough or extend far enough north to prevent breach at both the tank traps and several hundred meters north of the proposed HCD and permanent Beach Landing Facility (BLF). A breach at either point would enter the Minsmere Levels close to the SSSI crossing and threaten the stability of this design of crossing. A bridge design, as originally proposed in early consultations, would be environmentally more neutral and less threatened should a breach occur.
5. The temporary BLF options are proposed in conjunction with a variety of rail options to reduce the reliance on HGV transport for aggregate and other suitable materials. However, all the options show a similar design and are situated in a single position. Effectively any comment on the appropriateness of these options will constrain the ability of EDF to make good on their goal to reduce the use of HGV transportation. EDF’s proposed design should be that which minimises the coastal impact whilst maximising the goal of reducing HGV transport in conjunction with expanded rail. It has been indicated that an alternative might be for a conveyor belt jetty that would have much less impact than the previous jetty, as proposed in prior consultations but rejected at consultation 3 due to adverse coastal and environmental impacts. It would be quite unacceptable if such a jetty was eventually proposed for the DCO amendment in January or even later in the examination process.
6. We remain concerned that the new SSSI crossing design as a 30m wide culvert with embankments at both ends will still have significant impact on hydrology between Sizewell Marsh and Minsmere South Levels and ultimately Minsmere Sluice. This structure has no final design, runs across deep peat and any compression beneath the structure will alter groundwater response. The 55m long tunnel beneath the structure will not provide an appropriate habitat connection between the two designated areas. A bridge supported by pillars would not result in peat compression with attendant groundwater response or the level of habitat loss and habitat connectivity that this design will potentially result in.
Coast and Shoreline
7. The consequences of raising the crest of the HCD to 14m from 10m will be the advancement of the toe of the defence by some 8m towards the sea unless the crest of the HCD can be moved back towards the platform itself, which is unlikely given the existing space constraints on the platform. This is likely to mean the toe of the defence ends up below the beach in front of the existing sacrificial dune. It also means that the existing sacrificial dune will be destroyed and the beach itself will be disturbed.
8. The toe of the initial HCD will finish at AOD which is inadequate for a competent HCD.
9. In the DCO the expected exposure of the HCD was given as around 2050. For a HCD 8m closer to the sea, this date will be significantly advanced.
10. No information, maps or drawings are given to show where the new HCD toe is relative to the existing sacrificial dune making any assessment of this new proposal impossible.
11. In 2046 it is proposed that the HCD is adapted and the crest raised a further 1m to 15m, a new layer of rock armour laid on top of the original HCD and the toe of the adaptation will go beyond the original toe and finish below AOD. However, no dimensions or final depth of the toe are given. For any HCD defence to be competent it needs to finish below Mean Low Water Springs. Whether this new toe achieves that is not indicated and yet again it is not clear where in relation to the current sacrificial dune and beach any of these sketch plans for the HCD refer.
12. It is questionable, given the initial HCD will be exposed early and the toe being only at AOD, that adaptation will be possible as it is likely that the initial HCD will be being undermined by normal tidal action in around 2046. Any severe storm could accelerate exposure significantly based on experience both north and south of the Sizewell frontage.
13. In the DCO excessive reliance is placed upon sediment accretion north of the HCD and BLF to stabilise and prevent breach into South Minsmere Levels and close to the SSSI crossing. Such reliance is unfounded and represents a real risk to the site and all structures to the north of the site.
14. We note that in the Sizewell B Facilities Relocation planning application, a reference to a breach at the tank traps as being the worst-case planning scenario and proceed to look at the flood risk assessment (FRA) based on this breach point. Given the eroding nature of the coast at this point, it is highly likely that breach would occur both at the tank traps and at the point examined in Stage 3 consultation. The flood zones that run behind the sacrificial dune to the Leiston Drain combined with HCD at the BLF and new northern edge of the platform would divert the breach inland to meet the Leiston Drain and the proposed new “bridge” and embankments which are not protected. Excessive reliance on exposure of the new HCD creating sufficient accretion to prevent breach at the tank traps and further north fails to apply a cautious approach to the overall safety of the site and its access.
15. In the DCO document a Soft Coastal Defence feature (SCD) is discussed along with some strategies for maintaining it as it is eroded naturally by wave action as per the current sacrificial dune. However, this consultation seems to question the effectiveness of any SCD, and no discussion is entered into about how it might be maintained.
16. As the HCD is significantly forward of the DCO proposal, it is likely that the SCD will be unsustainable and that natural embayment once the northern end of the HCD and BLF are exposed will result in any SCD being removed. The embayment south of the new HCD may result in damage to the soft and hard defences at SZC, SCB and SZA. Additional modelling and evidence for examining the effect of the new HCD, both un-adapted and adapted, and any associated SCD is totally lacking in this consultation. This is wholly unacceptable.
Surface, and Ground Water Management
17. We remain concerned that insufficient information has been given or modelled to conclude that there will not be significant changes to both surface and groundwater behaviour and that as a result water quality, particularly in Sizewell Marsh SSSI, will not be affected.
Spoil, Sand & Gravel Heaps
18. The addition of another stockpile is unacceptable and the comments in our Stage 3 Consultation Response remain unchanged.
Temporary Beach Landing Facility
19. The four options for this additional facility on the coast need to be optimised based on the reduction of HGV usage through a combination of increased rail and the capacity of this temporary BLF.
20. MLSG contends that the addition of a temporary BLF can only be justified if we can be assured that any impact on coastal longshore drift is minimised. Otherwise Thorpeness and Aldeburgh will be exposed to erosion of the kind that happened during the construction of Sizewell B.
21. It would appear from the information provided by EDF that the structure that minimises negative impact is option 4, as it goes beyond the in-shore bar and requires less intervention in terms of dredging or installation of grillage. However, we note that EDF have said in meetings with Theberton and Eastbridge Parish Council that additional piling maybe required to stabilise the structure overwinter when the BLF is inoperative. Further evidence of the impact on longshore drift is required to ensure that any final design and piling plan does not impede sediment flow across the frontage.
22. It was suggested at the same meeting, referred to in 21 above, the possibility that a simple jetty structure may in the end be used, sufficient to support the operation of the conveyor system. If this is truly a possibility, it is unacceptable that this does not appear in this consultation and simply confirms an impression that insufficient preparation has been done prior to submission of the DCO or even this consultation.
23. MLSG remains unconvinced that the current proposal makes an adequate case for a two-reactor development on the 32-hectare platform as there are significant issues surrounding the HCD and the ability of EDF to manage all the elements into such a confined space.
24. MLSG supports the Environment Agency in their calls in their Stage 3 response for more complete Environmental Impact information in order that they can make an adequate assessment of the proposal
25. MLSG supports the SCDC and SCC in their response regretting that insufficient information has been provided to adequately respond to the consultation and assess whether the proposal provides a sustainable benefit for the community and county as a whole. Unfortunately, this request and lack of response from EDF has been characteristic of all stages of consultation over the past 9 years and it is regrettable that we will have to wait until the Development Consent Order application to get a real view of the impact of this development, even though we can see that the impact to the surrounding designated landscapes and coast will be significant and long lasting.