Representation by Residents of Corner Farm (Residents of Corner Farm)
- Date submitted
- 13 January 2024
- Submitted by
- Members of the public/businesses
Our primary concern is in relation to survivability in the event of a pipeline rupture. Unfortunately, throughout the consultation process, the applicant has been unwilling to engage with affected parties at a technical level, so we have had to rely on estimates of risk based on research published by third parties. Firstly, we turn to 'Technical guidance on hazard analysis for onshore carbon capture installations and onshore pipelines: a guidance document' (Energy Institute, London; 2010). SLOT, SLOD, and blast ranges are estimated for a range of pipe diameters at 117 barg; higher pressures would render these underestimates. Ranges for SLOT and blast limit of fatal risk may be interpolated for a 24" pipeline - both are linear functions of pipe diameter. So, for a 24" pipe, the blast limit of fatal risk would be approximately 90 m. For a 24" full-diameter rupture, SLOT would be exceeded at approximately 345 m directly downwind. For a 4" jet, considered to be an order of magnitude more common, SLOT would be exceeded at approximately 185 m for an unimpeded jet and at approximately 320 m for an impeded jet (e.g. from under a roadway). For estimates of SLOT within residential buildings, we turn to Lyons CJ, Race JM, Hopkins HF, and Cleaver P (2015) 'Prediction of the consequences of a CO2 pipeline release on building occupants' In: Hazards 25. Institution of Chemical Engineers Symposium Series, 160. The Institution of Chemical Engineers, GBR. (Later publications test the model against experiment.) Using the DNV-GL COOLTRANS model, a simplified infiltration scenario, and assuming valve closure within 15 minutes and pipeline CO2 at 30°C, Lyons concludes that “safe shelter will be provided in any building located more than 150m from the release for this case study”. Leakier buildings such as the average old Lincolnshire farmhouse, will reach a SLOT DTL at greater distances (see Lyons’ published thesis), but in the absence of better data, this is an appropriate working figure. Following the first round of consultation, an alteration was made to the preferred route as it passes Grimoldby. The original route, which we assume met other QRA requirements, placed 8 homes, on Pickhill Lane and around the junction of Northgate Lane with Middlesykes Lane, within outdoor SLOT range for a full-bore rupture. None of these were within indoor SLOT range and none within fatal blast range. The diverted route placed 7 different homes, on Red Leas Lane, Marsh Lane, and Pickhill Lane, within outdoor SLOT range. One of these (ours) was placed within both indoor SLOT range and fatal blast range. Following further consultation a small adjustment was made to the preferred route, bisecting the gap between our house and the adjacent farm. If the route indeed sticks religiously to the midline between the farmhouses, neither would lie within the 90 m range of fatal blast estimated above. However, if the line deviated significantly or the pressure significantly exceeded 117 barg (The operating range in Dense Phase will be 100 – 150 barg.), one or both of the houses would fall back within fatal blast range. Both houses now lie within the indoor SLOT range of 150 m and could not be relied upon for safe refuge in the event of a rupture. Escape routes may be rendered unusable. We assume that the applicant has used a QRA approach similar to that outlined by Cooper R, and Barnett J, 'Pipelines for transporting CO2 in the UK' Energy Procedia 63 (2014) 2412 – 2431, and that the requirements of this model were satisfied by both the original preferred route and the diverted route. The difficulty of this approach is that, while it controls overall societal risk, it can leave residents of smaller clusters and isolated dwellings exposed to elevated individual risk and without safe refuge in the event of a rupture. These residents can effectively be left living under the sword of Damocles. In our response to the consultation on the diverted route, we suggested practicable alternative routes, which would take all affected dwellings on the diversion out of both indoor and outdoor SLOT range. The applicant misinterpreted our suggestions, rejecting the use of corridor E-1B as it was difficult to avoid the ribbon development on the B1200, and implying that our suggestion would place a local school at risk. The school in question actually closed in 2016 and our suggested route passed nowhere near to where it used to be or to any other school. Our suggested route used part of route E-1B, linked to E-2 by a short new section east of Grimoldby and crossing the B1200 on the current preferred route. Table 6-3 of the submitted Consultation Report (Document Reference: EN070008/APP/5.1) lists only the applicant's misinterpretation of one of our suggested alternative routes under DCR058, concluding that "it would therefore not bring any benefits in terms of avoiding properties", which is incorrect. The applicant also objected that corridor E1-B entered flood zones 2 and 3 earlier than they would prefer. Set against safety concerns this is an insubstantial objection. The original diversion itself increased the length crossing flood zones 2 and 3 at the Grayfleet, and the incursion into flood zones 2 and 3 along the first part of E1-B is minor in comparison with the preferred route after it crosses the B1200. In Appendix F6 (Main theme: Area north of Grimoldby), the applicant's only response to this point is 'Noted'. In our response to the consultation on the adjustment to the diverted route, we clarified our suggested alternative route, with diagrams to avoid ambiguity, and suggested other, shorter alternatives that might incur less onerous reconsultation. Any of these suggestions would have clear safety benefits. In Appendix F6, the applicant's only response to these suggestions is 'Noted'. In Appendix F6, the applicant's response under the sub-theme 'Safety' is frustratingly superficial. This is PR, not an adequate response to consultation. Given that experience with CCS is limited and that, as the HSE acknowledges, safety codes remain a work in progress, we suggest that risk mitigation should take priority in design and planning and we would urge a cautious, layered approach, making use of 'safe distance' wherever practicable, rather than relying predominantly on engineering solutions. QRA calibrated to control societal risk should at minimum be supplemented by a safe-refuge requirement in residential settings to control individual risk. That is, at minimum, to control indoor exposure in the event of a rupture below the SLOT DTL, and, on the ALARP principle, wherever practicable, to control outdoor exposure below the SLOT DTL. We do not believe that the applicant has yet done as much as they should or could reasonably do to reduce the risk to residents on the diverted route. We hope that, with sufficient encouragement, they may yet reconsider their preferred route in the interests of safety.