Marine Mudflat Monitoring Services for Nuclear Power Studies

The BEEMS (British Energy Estuarine and Marine Studies) programme is funded by NNB Generating Company HPC (NNB GenCo).

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 element described below; Description of the sample collection: The mudflat monitoring in Bridgwater Bay encompasses the collection of 6 replicates samples at 11 stations in Bridgwater Bay and Wick St Lawrence twice a year (February and August).

The replicate samples are collected with a 0.01m2 core and the sediment is sieved through a 0.5 mm mesh sieve. The Macoma balthica individuals (only bivalve present in the mudflat) are hand-picked on the sieve during the survey and stored in separated glass vials. The potentially high number of individuals of this species are therefore not included in the samples.

All benthic organisms are transferred into Nalgene bottles and fixed with 4% formaldehyde. Summary of deliverables: • Analysis of two survey batches of samples per year (collected in February and August), 66 samples per survey. • Externally audited, quality-controlled abundance / biomass matrices as per template provided, with current nomenclature (Primary processing and Audit lab).

• One reference collection (Primary processing lab) - the collection will be updated over the duration of the contract as additional species are encountered in the samples. • Internal Quality Control logs (Primary processing lab). • Audited Quality Control report (Audit lab). • Regular project summary updates and correspondence between primary processing and audit lab (Primary processing and Audit lab).