CEFAS24-07 Contract for the provision to provide subtidal Sabellaria surveys at Hinkley Point C

The Hinkley BEEMS (British EDF Estuarine and Marine Studies) programme is funded by New Nuclear Build Generation Company (HPC) Ltd. Through this programme, Cefas provide authoritative scientific information on the marine and transitional waters in the vicinity of potential new build nuclear power stations and require a competent supplier to deliver the following; Cefas require a supplier to conduct subtidal monitoring surveys for the Hinkley Point C (HPC) Nuclear New Build (NNB) project to meet regulatory environmental monitoring requirements. At HPC, the Sabellaria spp. monitoring programme focuses on mapping and assessing the condition (i.e. reefiness) of the subtidal biogenic reefs present on the seabed at Hinkley Point. The objective of the proposed surveys is to measure the spatial extent of the Sabellaria spp. by collecting high-resolution Side Scan Sonar (SSS) data of the area of interest and to ground-truth an area of the seabed with an Adaptive Resolution Imaging Sonar (ARIS) camera (Sound Metrics ARIS Explorer 3000) and RT3 rotator to confirm the seabed type and the presence or absence of Sabellaria spp. tube aggregations. A survey is required in Autumn/Winter for Financial Year 24/25 (November 2024 - February 2025) and a second survey in Spring (April/May) 2025. The specified 'Sound Metrics ARIS Explorer 3000' is required to ensure quality and data consistency with the previous survey, and therefore it is a requirement for the supplier to either own or be able to hire, the equipment for the survey. The Autumn/Winter survey extent comprises an area of 9.7 km2, with the Spring survey extent 5.3 km2, extending to approximately 4.5 km offshore from Hinkley Point.