Site Event/Activity record ECH6724 - Chester Racecourse - Proposed Events Building with Undercroft Parking Area: Geoarchaeological Evaluation

A geoarchaeological evaluation was undertaken in 2019 for an area of land at Chester Racecourse for which planning permission is being sought for development of an Events Building with undercroft car-parking, centred at SJ 40000 66214. The site lies within Chester’s Primary Archaeological Character Zone, extends over one of Chester’s Archaeological Character Areas and is within the Chester City Centre Conservation Area. The footprint of the proposed Events Building lies within an area of land reclaimed from the River Dee in the ninteenth century. It has the potential to have archaeological features of medieval or Roman origin within alluvial deposits. Due to deep deposition and waterlogged contexts there is also a potential for the preservation of organic materials. Whilst, due to their probable depth, it would be fair to suppose that the overall potential for archaeological remains at the Site pre-dating the post-medieval period to be low-medium there still remains the possibility that deposits and artefacts within or masked by alluvial deposits, could be present. This work follows on from a wider area assessment undertaken in 2018 (ECH6623), also a deposit modelling exercise (ECH6639). The deposit model was designed to address uncertainty regarding the impact of development at Chester Racecourse on subsurface archaeological assets. The geoarcheological evaluation was undertaken to further inform the deposit model, by examining the depths of made grounds and inert alluvial deposits on the site by means of core recovery via boreholes (seven boreholes were proposed, however only six were drilled). Two of the boreholes, numbers 1 and 7 sought to reach the underlying geology. Neither of the cores hit sandstone, however, they are sufficient to prove the absence of significant archaeological features of antiquity which would be impacted by the development as the proposed ground reduction for the undercroft car park is 3m. Boreholes 2, 3, 4 and 6 were drilled to 5m below the ground surface. The overburden of made ground was predicted to be around 3m. The depth of the observed make up layers, and residual athropogenic features of probable post-medieval origin vary between 0.9m and 2.75m below the ground surface. The evaluation demonstrated that the Site has been previously substantially landscaped and developed on land which began to become available on banks of the River Dee from the late medieval period. Samples from the lens of organic materials in borehole 7 (peat and wood) found at 18m below the ground surface were sent to University of Oxford Radiocarbon Accelerator Unit for radiocarbon dating. (1)